A high-efficiency mode of high-low seedbed cultivation(HLSC)has been listed as the main agricultural technology to increase land utilization ratio and grain yield in Shandong Province,China.However,limited information...A high-efficiency mode of high-low seedbed cultivation(HLSC)has been listed as the main agricultural technology to increase land utilization ratio and grain yield in Shandong Province,China.However,limited information is available on the optimized water and nitrogen management for yield formation,especially the grain-filling process,under HLSC mode.A three-year field experiment with four nitrogen rates and three irrigation rates of HLSC was conducted to reveal the response of grain-filling parameters,grain weight percentage of spike weight(GPS),spike moisture content(SMC),and winter wheat yield to water and nitrogen rates.The four nitrogen rates were N1(360 kg ha^(-1) pure N),N2(300 kg ha^(-1) pure N),N3(240 kg ha^(-1) pure N),and N4(180 kg ha^(-1) pure N),respectively,and the three irrigation quotas were W1(120 mm),W2(90 mm),and W3(60 mm),respectively.Results showed that the determinate growth function generally performed well in simulating the temporal dynamics of grain weight(0.989<R^(2)<0.999,where R2 is the determination coefficient).The occurrence time of maximum filling rate(T_(max))and active grain-filling period(AGP)increased with the increase in the water or nitrogen rate,whereas the average grain-filling rate(G_(mean))had a decreasing trend.The final 1,000-grain weight(FTGW)increased and then decreased with the increase in the nitrogen rates and increased with the increase in the irrigation rates.The GPS and SMC had a highly significant quadratic polynomial relationship with grain weight and days after anthesis.Nitrogen,irrigation,and year significantly affected the T_(max),AGP,G_(mean),and FTGW.Particularly,the AGP and FTGW were insignificantly different between high seedbed(HLSC-H)and low seedbed(HLSC-L)across the water and nitrogen levels.Moreover,the moderate water and nitrogen supply was more beneficial for grain yield,as well as for spike number and grain number per hectare.The principal component analysis indicated that combining 240-300 kg N ha^(-1) and 90^(-1)20 mm irrigation quota could improve grain-filling efficiency and yield for the HLSC-cultivated winter wheat.展开更多
Fuji apple(Malus×domestica Borkh.)is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality.Ethylene emission can induce respiration,which ...Fuji apple(Malus×domestica Borkh.)is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality.Ethylene emission can induce respiration,which would reduce postharvest quality and increase storage losses.In order to maintain fruit quality and extend shelf life,apples are usually stored in a low-temperature environment after harvest to reduce the formation of ethylene.Volatile aroma components are regarded as one of the most important aspects of flavor quality and a key factor for apple quality grading and customer satisfaction.Ethylene emission and its relationship with volatile aromas during low temperature,however,have not been determined.In this study,the dynamic changes of volatile aroma compounds of Fuji apples stored at 4°C were detected and analyzed for 42 days.The variation of ethylene released from Fuji apple was studied correspondingly.The results showed that ethyl butyrate,ethyl caproate,ethyl 2-methylbutyrate and 2-methylbutyl acetate were the main aroma components of Fuji apple.The change in ethylene emission and the normalized peak area of volatile aroma compounds exhibited a similar tendency that increased significantly from the 3rd day to the peak on the 14th day and then decreased;there was a positive linear correlation between them with a correlation coefficient of 0.79(P<0.05).Therefore,ethylene release can be used as a potential indicator for evaluation of volatile aroma compounds in apples.Using ethylene emission as an indicator could reduce the difficulty and complexity of volatile aroma evaluation,which could be a new non-destructive inspection choice for apple flavor quality assessment.展开更多
The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen（N）levels are important indicators of the effect...The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen（N）levels are important indicators of the effect of reclaimed water irrigation on environment.This study evaluated soil physicochemical properties and microbial community structure in soils irrigated with reclaimed water and receiving varied amounts of N fertilizer.The results indicated that the reclaimed water irrigation increased soil electrical conductivity（EC）and soil water content（SWC）.The N treatment has highly significant effect on the ACE,Chao,Shannon（H）and Coverage indices.Based on a 16S ribosomal RNA（16S rRNA）sequence analysis,the Proteobacteria,Gemmatimonadetes and Bacteroidetes were more abundant in soil irrigated with reclaimed water than in soil irrigated with clean water.Stronger clustering of microbial communities using either clean or reclaimed water for irrigation indicated that the type of irrigation water may have a greater influence on the structure of soil microbial community than N fertilizer treatment.Based on a canonical correspondence analysis（CCA）between the species of soil microbes and the chemical properties of the soil,which indicated that nitrate N（NO3-–-N）and total phosphorus（TP）had significant impact on abundance of Verrucomicrobia and Gemmatimonadetes,meanwhile the p H and organic matter（OM）had impact on abundance of Firmicutes and Actinobacteria significantly.It was beneficial to the improvement of soil bacterial activity and fertility under 120 mg kg^-1 N with reclaimed water irrigation.展开更多
Sequence-specific nucleases(SSN) that generate double-stranded DNA breaks(DSBs) in genes of interest are the key to site-specific genome editing in plants. Genome editing has developed into one method of reducing unde...Sequence-specific nucleases(SSN) that generate double-stranded DNA breaks(DSBs) in genes of interest are the key to site-specific genome editing in plants. Genome editing has developed into one method of reducing undesirable traits in crops by the induction of knockout mutations. Different SSN-mediated genome-editing systems, including LAGLIDADG homing endonucleases or meganucleases, zinc-finger nucleases, transcription activator-like effector nucleases and clustered regularly interspaced short palindromic repeats, are emerging as robust tools for introducing functional mutations in polyploid crops including citrus, wheat, cotton, soybean, rapeseed, potato, grapes, Camelina sativa,dandelion, and tobacco. The approach utilizes knowledge of biological mechanisms for targeted induction of DSBs and their error-prone repair, allowing highly specific changes at designated genome loci. In this review, we briefly describe genome-editing technologies and their application to genetic improvement of polyploid crops.展开更多
A dwarf mutant of rice （Oryza sativa L.） by mutagenesis of ethylene methylsulfonate （EMS） treatment from Nipponbare was identified. The mutant exhibited phenotypes of dwarfism and withered leaf tip （dwll）. Based...A dwarf mutant of rice （Oryza sativa L.） by mutagenesis of ethylene methylsulfonate （EMS） treatment from Nipponbare was identified. The mutant exhibited phenotypes of dwarfism and withered leaf tip （dwll）. Based on the intemode length of dwll, this mutant belongs to the dm type of dwarfing. Analysis of elongation of the second sheath and m-amylase activity in endosperm showed that the phenotype caused by dwll was insensitive to gibberellin acid treatment. Using a large F2 population derived from a cross between the dwll and an indica rice variety, TN1, the DWL1 gene was mapped to the terminal region of the long arm of chromosome 3. Fine-mapping delimited it into a 46 kb physical distance between two STS markers, HL921 and HL944, where 6 open reading frames were predicted. Cloning of DWL1 will contribute to dissecting molecular mechanism that regulates plant height in rice, which will be beneficial to molecular assisted selection of this important trait.展开更多
Dissimilatory Fe（Ⅲ） reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe（Ⅱ） species accumulation could indicate t...Dissimilatory Fe（Ⅲ） reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe（Ⅱ） species accumulation could indicate the reduction ability. The effects of different green manures on Fe（Ⅲ） reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch （RRV）, rice-rice-rape （RRP）, rice-rice-ryegrass （RRG） and rice-rice-winter fallow （RRF）. Soils were sampled at flowering stage of milk vetch and rape （S1）, before transplantation （S2）, at tillering （S3）, jointing （S4）, and mature （S5） stages of the early rice, and after the harvest of the late rice （S6）. The contents of TFeHa （HCI-extractable total Fe）, Fe（Ⅱ）HCI （HCI-extractable Fe（Ⅱ） species） and Fe（Ⅲ）HCI （HCI- extractable Fe（Ⅲ） species） were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe（Ⅱ）HCI accumulation were investigated. The results showed that TFeHc~ in RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe（II）Ha increased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe（Ⅱ）Ha in RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe（Ⅲ）Ha showed oppositely, and Fe（Ⅱ）HCI/Fe（Ⅲ）HCI performed similarly to Fe（Ⅱ）HCI The maximum accumulation potential of Fe（Ⅱ）HCI was significantly higher in RRF, while the highest maximum reaction rate of Fe（Ⅱ）Ha accumulation appeared in RRG. Significant correlations were found between the indexes of Fe（Ⅱ）HCI accumulation and soil pH, oxidation-reduction potential （Eh） and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHa in red paddy soils, but promoted the ability of Fe（lll） reduction, especially the ryegrass; Fe（Ⅱ）Ha increased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.展开更多
Seven inorganic amendment materials were added into arsenic （As） contaminated soil at a rate of 0.5% （w/w）; the materials used were sepiolite, red mud, iron grit, phosphogypsum, ferrihydrite, iron phosphate, and l...Seven inorganic amendment materials were added into arsenic （As） contaminated soil at a rate of 0.5% （w/w）; the materials used were sepiolite, red mud, iron grit, phosphogypsum, ferrihydrite, iron phosphate, and layered double oxides （LDO）. Plant growth trials using rape （edible rape, Brassia campestris L.） as a bio-indicator are commonly used to assess As bio- availability in soils. In this study, B. campestris was grown in a contaminated soil for 50 days. All of the inorganic amend- ments significantly inhibited the uptake of As by B. campestris. Following soil treatment with the seven aforementioned inorganic ammendments, the As concentrations in the edible parts of B. campestris were reduced by 28.6, 10.5, 8.7, 31.0, 47.4, 25.3, and 28.8%, respectively, as compared with the plants grown in control soil. The most effective amendment was ferdhydrite, which reduced As concentration in B. campestris from 1.84 to 0.97 mg kg-~, compared to control. Furthermore, ferrihydrite-treated soils had a remarkable decrease in both non-specifically sorbed As and available-As by 67 and 20%, respectively, comparing to control. Phosphogypsum was the most cost-effective amendment and it showed excellent performance in reducing the water soluble As in soils by 31% and inhibiting As uptake in B. campestris by 21% comparing to control. Additionally, obvious differences in As transfer rates were observed in the various amendments. The seven amendment materials used in this study all showed potential reduction of As bioavailability and influence on plant growth and other biological processes still need to be further explored in the long term.展开更多
Thaumatin-like protein (TLP) plays an important role in combating plant pathogen infection.Common root rot caused by Bipolaris sorokiniana and leaf rust caused by Puccinia triticina (Pt) are major fungal diseases in w...Thaumatin-like protein (TLP) plays an important role in combating plant pathogen infection.Common root rot caused by Bipolaris sorokiniana and leaf rust caused by Puccinia triticina (Pt) are major fungal diseases in wheat.The disease responses of TaTLP1-overexpressing transgenic lines (TaTLP1-OE) were evaluated after inoculation with each pathogen.The TaTLP1-OE lines had no apparent differences in tiller number and 1000-kernel weight from the wild type Jinan Wheat No.1 (JW1),whereas resistance to leaf rust and common root rot was improved,resulting from activated peroxidase and b-1,3-glucanase after B.sorokiniana infection,and reactive oxygen species-related genes were upregulated in Ta TLP1-OE lines after Pt infection.These results indicated that stable expression of TaTLP1 increased resistance against both diseases.展开更多
One of the main food crops in the world,rice can accumulate high levels of arsenic from flooded paddy soils,which seriously threatens human health.Soaking,a common processing method for brown rice products,especially ...One of the main food crops in the world,rice can accumulate high levels of arsenic from flooded paddy soils,which seriously threatens human health.Soaking,a common processing method for brown rice products,especially for brown rice noodles,was investigated in this study.Japonica rice(Dao Hua Xiang No.2)and Indica rice(Ye Xiang You No.3)were selected for studying the effects of soaking on arsenic concentrations,species,and distributions.Results revealed that soaking can efficiently remove arsenic in these two rice varieties,and the main part of removal is endosperm with the maximal rate of about 40%.Inorganic arsenic(I-As)(about 85%)is the main species of arsenic reduction.Meanwhile,the variations of four other elements(i.e.,Mg,Ca,Zn,and Fe)were analyzed.Collectively,the findings of this study indicate that soaking can efficiently remove arsenic in brown rice under controlled soaking conditions,which thereby reduces the arsenic intake for brown rice customers.展开更多
Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).Drip fertigation is considered to b...Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).Drip fertigation is considered to be an effective method for improving N use efficiency and reducing losses,while the performance of drip fertigation in winter wheat is limited by poor N scheduling.A two-year field experiment was conducted to evaluate the growth,development and yield of drip-fertigated winter wheat under different split urea (46%N,240 kg ha^(-1)) applications.The six treatments consisted of five fertigation N application scheduling programs and one slow-release fertilizer (SRF) application.The five N scheduling treatments were N0–100 (0%at sowing and 100%at jointing/booting),N25–75 (25%at sowing and 75%at jointing and booting),N50–50(50%at sowing and 50%at jointing/booting),N75–25 (75%at sowing and 25 at jointing/booting),and N100–0 (100%at sowing and 0%at jointing/booting).The SRF (43%N,240 kg ha^(-1)) was only used as fertilizer at sowing.Split N application significantly (P<0.05) affected wheat grain yield,yield components,aboveground biomass (ABM),water use efficiency(WUE) and nitrogen partial factor productivity (NPFP).The N50–50 and SRF treatments respectively had the highest yield(8.84 and 8.85 t ha^(-1)),ABM (20.67 and 20.83 t ha^(-1)),WUE (2.28 and 2.17 kg m^(-3)) and NPFP (36.82 and 36.88 kg kg^(-1)).This work provided substantial evidence that urea-N applied in equal splits between basal and topdressing doses compete economically with the highly expensive SRF for fertilization of winter wheat crops.Although the single-dose SRF could reduce labor costs involved with the traditional method of manual spreading,the drip fertigation system used in this study with the N50–50 treatment provides an option for farmers to maintain wheat production in the NCP.展开更多
In response to preharvest priming with exogenous methyl jasmonate(MeJA),tea plants adjust their physiological behavior at the molecular level.The whole-organism reconfiguration of aroma formation from the precursor to...In response to preharvest priming with exogenous methyl jasmonate(MeJA),tea plants adjust their physiological behavior at the molecular level.The whole-organism reconfiguration of aroma formation from the precursor to storage is poorly understood.In this study,we performed iTRAQ proteomic analysis and identified 337,246,and 413 differentially expressed proteins in tea leaves primed with MeJA for 12 h,24h,and 48 h,respectively.Furthermore,a total of 266 nonvolatile and 100 volatile differential metabolites were identified by utilizing MS-based metabolomics.A novel approach that incorporated the integration of extended self-organizing map-based dimensionality was applied.The vivid time-scale changes tracing physiological responses in MeJA-primed tea leaves are marked in these maps.Jasmonates responded quickly to the activation of the jasmonic acid pathway in tea leaves,while hydroxyl and glycosyl jasmonates were biosynthesized simultaneously on a massive scale to compensate for the exhausted defense.The levels ofα-linolenic acid,geranyl diphosphate,farnesyl diphosphate,geranylgeranyl diphosphate,and phenylalanine,which are crucial aroma precursors,were found to be significantly changed in MeJA-primed tea leaves.Green leaf volatiles,volatile terpenoids,and volatile phenylpropanoids/benzenoids were spontaneously biosynthesized from responding precursors and subsequently converted to their corresponding glycosidic forms,which can be stably stored in tea leaves.This study elucidated the physiological response of tea leaves primed with exogenous methyl jasmonate and revealed the molecular basis of source and sink changes on tea aroma biosynthesis and catabolism in response to exogenous stimuli.The results significantly enhance our comprehensive understanding of tea plant responses to exogenous treatment and will lead to the development of promising biotechnologies to improve fresh tea leaf quality.展开更多
This article conducts empirical analysis of rice growers' behavior of productive capital input and the influencing factors,using the input-output survey data concerning rice growing by 305 peasant households in 20...This article conducts empirical analysis of rice growers' behavior of productive capital input and the influencing factors,using the input-output survey data concerning rice growing by 305 peasant households in 2009 in Huanan County and Huachuan County,Jiamusi City,Heilongjiang Province.I use Logit model to carry out econometric test of factors influencing the possibility of fixed productive investment.The test results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level,peasant households' expectation of the minimum purchase price of rice,have significant effect on whether to conduct fixed productive investment,whether there are disasters has no significant effect on the scale of peasant households' productive investment.Then I use Tobit model to carry out econometric test of factors influencing the scale of productive capital input.The results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level and family housing value,peasant households' expectation of the minimum purchase price of rice,whether there are disasters,have significant effect on the scale of peasant households' productive investment.On the basis of model test results,in order to promote the rice growers to increase fixed productive input and increase productive capital input,rational recommendations are put forward as follows:raising the minimum purchase price of rice,scaling up rice growing,making every effort to promote the educational level of rice growers,ensuring that the rice growers obtain productive capital input loans timely.展开更多
MicroRNAs （miRNAs） are -21 nucleotide （nt）, endogenous RNAs that regulate gene expression in plants. Increasing evidence suggests that miRNAs play an important role in species-specific development in plants. Howev...MicroRNAs （miRNAs） are -21 nucleotide （nt）, endogenous RNAs that regulate gene expression in plants. Increasing evidence suggests that miRNAs play an important role in species-specific development in plants. However, the detailed miRNA profile divergence has not been performed among tomato species. In this study, the small RNA （sRNA） profiles of Solanum lycopersicum cultivar 9706 and Solanum habrochaites species PI 134417 were obtained by deep sequencing. Sixty-three known miRNA families were identified from these two species, of which 39 were common. Further miRNA profile comparison showed that 24 known non-conserved miRNA families were species-specific between these two tomato species. In addition, six conserved miRNA families displayed an apparent divergent expression pattern between the two tomato species. Our results suggested that species-specific, non-conserved miRNAs and divergent expression of conserved miRNAs might contribute to developmental changes and phenotypic variation between the two tomato species. Twenty new miRNAs were also identified in S. lycopersicum. This research significantly increases the number of known miRNA families in tomato and provides the first set of small RNAs in S. habrochaites. It also suggests that miRNAs have an important role in species-specific plant developmental regulation.展开更多
Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges...Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges and at what magnitude and more importantly, what can be learn to improve the rice yield in Nigeria. Based on 2013/2014 survey, a total sample of 400 famers were randomly interviewed;164 from Niger State of Nigeria and 236 from Hainan province of China. The study collate the perception of farmers to rice production constraints categorized into biotic, abiotic and socioeconomics. Biplot analysis was employed to examine multivariate pattern of their perceptions towards production constraints. The multivariate technique simultaneously displaying different yield levels and factor constraints in data matrix providing the inter-unit distances, variance and correlations of variables. According to the study, Niger state farmers identified socioeconomic constraint as the major factors to production and attributed it to lack of or insufficient investment while the Hainan farmers majorly identified abiotic constraints. The study also indicated that great potential remain to further improve rice yield in both regions especially in Nigeria given the appropriate investment on essential inputs. This study is of great use to extension officers more so, given the investment in Africa, policy makers take advantage of the bilateral and multilateral relationship to invest ease transfer of agricultural information and technologies between or among partners.展开更多
Diabetes mellitus(DM)is a pressing global public health issue with a high incidence of morbidity and mortality due to its complications.Although there are many medicines available for the treatment of DM,long-term use...Diabetes mellitus(DM)is a pressing global public health issue with a high incidence of morbidity and mortality due to its complications.Although there are many medicines available for the treatment of DM,long-term use causes various adverse effects,such as diarrhea,vomiting,and nausea.Tea,owing to its richness of diverse bioactive components including tea polyphenols,tea polysaccharides,and alkaloids,has displayed promising antidiabetic properties.Screening antidiabetic bioactive compounds derived from teas is receiving increasing attention.Epidemiological and clinical investigations have demonstrated an inverse relationship between tea consumption and the incidence of DM.Both in vitro and in vivo experiments have substantiated the hypoglycemic effects of tea and its bioactive components through several possible mechanisms,including improvement of insulin resistance,inhibition of carbohydrates digestion and absorption(inhibitα-amylase andα-glucosidase activity),regulations of gut microbiota,inflammatory cytokines,and gene and protein expressions in the insulin signaling pathway,as well as amelioration of DM complications.This comprehensive review provides an up-to-date overview of the hypoglycemic properties associated with tea and its bioactive components.It also delves into their potential mechanisms,offering a theoretical foundation for further research into tea's antidiabetic properties and for the development of innovative antidiabetic functional products.展开更多
Diterpenes are the most complex and abundant plant metabolites,some of which play significant roles in both primary and secondary metabolism.Ent-kaurene synthase is the key enzyme for gibberellins(GAs)biosynthesis,whi...Diterpenes are the most complex and abundant plant metabolites,some of which play significant roles in both primary and secondary metabolism.Ent-kaurene synthase is the key enzyme for gibberellins(GAs)biosynthesis,which may act as a catalyst in the formation of entkaurene,the precursor for GAs,by cyclization or rearrangement of the substrate ent-copalyl diphosphate(ent-CPP).Ilex latifolia Thunb(Aquifoliaceae)is a widely distributed Chinese plant whose leaves are used to process a popular Chinese bitter tea named'Kudingcha',which has anti-microbial,anti-oxidant and anti-inflammatory properties.Here,we isolated a diterpene synthase gene from the leaf transcriptome of I.latifolia,and further identified its biosynthesis activity by in vitro enzymatic testing.The heterologous expressed ent-kaurene synthase of I.latifolia(IlKS)in E.coli could catalyze ent-copalyl diphosphate(ent-CPP)to form ent-kaurene.Tissue-specific expression indicated that IlKS had the highest transcript level in roots which is maybe the major location of ent-kaurene biosynthesis.This study would help us to determine diterpenoid metabolism and GAs biosynthesis in I.latifolia,to better understand the regulation function of GAs in growth and development.展开更多
Nymphaea is a key genus of the ANA grade(Amborellales,Nymphaeales,and Austrobaileyales)of basal flowering plants,which serve as a key model to study the early evolution of floral traits.In this study,we comprehensivel...Nymphaea is a key genus of the ANA grade(Amborellales,Nymphaeales,and Austrobaileyales)of basal flowering plants,which serve as a key model to study the early evolution of floral traits.In this study,we comprehensively investigated the emission,biosynthesis,and biological function of the floral scent in a night-blossoming waterlily Nymphaea prolifera.The headspace volatile collection combined with GC-MS analysis showed that the floral scent of N.prolifera is predominately comprised by methylated benzenoids including anisole,veratrole,guaiacol,and methoxyanisole.Moreover,the emission of these floral benzenoids in N.prolifera exhibited temporal and spatial pattern with circadian rhythm and tissue specificity.By creating and mining transcriptomes of N.prolifera flowers,12 oxygen methyltransferases(NpOMTs)were functionally identified.By in vitro enzymatic assay,NpOMT3,6,and 7 could produce anisole and NpOMT5,7,9,produce guaiacol,whereas NpOMT3,6,9,11 catalyzed the formation of veratrole.Methoxyanisole was identified as the universal product of all NpOMTs.Expression patterns of NpOMTs provided implication for their roles in the production of the respective benzenoids.Phylogenetic analysis of OMTs suggested a Nymphaea-specific expansion of the OMT family,indicating the evolution of lineage-specific functions.In bioassays,anisole,veratrole,and guaiacol in the floral benzenoids were revealed to play the critical role in repelling waterlily aphids.Overall,this study indicates that the basal flowering plant N.prolifera has evolved a diversity and complexity of OMT genes for the biosynthesis of methylated benzenoids that can repel insects from feeding the flowers.These findings provide new insights into the evolutional mechanism and ecological significance of the floral scent from early-diverged flowering plants.展开更多
Effective silique number per plant(ESN), seeds per silique(SS), thousand seeds weight(TSW), silique length(SL) and silique density(SD) are important seed yield potential determinant traits in rapeseed(Brassica napus L...Effective silique number per plant(ESN), seeds per silique(SS), thousand seeds weight(TSW), silique length(SL) and silique density(SD) are important seed yield potential determinant traits in rapeseed(Brassica napus L.), which are controlled by quantitative trait loci(QTL). Mapping QTL to delimited chromosomal region offers an effective method for genetic dissection of these traits. A set of 96 double haploid(DH) lines were developed by crossing 2 Brassica napus lines R1 and R2, and an immortalized F_2(IF_2) population containing 124 combinations was developed by crossing those DH lines. DH populations were planted at 2 locations for 2 years and IF_2 populations were planted in 2 locations for 1 year. Based on the established 2,217.2 cM length high density genetic map, 42 QTLs were identified, with 26 QTLs detected repeatedly in different environments or populations, including 8 for SL, 7 for TSW, 4 for ESN, 4 for SS and 3 for SD. Among these identified QTLs, 3, 4, 1, 1 and 3 QTLs were considered as major QTLs for SL, TSW, ESN, SS and SD, respectively. In addition, 2 QTLs on A9 chromosome which control multiple traits were identified. These results warrant further study of fine mapping for yield and yield components.展开更多
To provide a theoretical basis for further improvement of Brassica napus yield, additive dominance with additive - by - additive epistatic effects （ ADAA） genetic model and a 6 X 8 partial dial- lel cross des...To provide a theoretical basis for further improvement of Brassica napus yield, additive dominance with additive - by - additive epistatic effects （ ADAA） genetic model and a 6 X 8 partial dial- lel cross design were used to analyze the genetic effects and correlations of five yield related traits of 14 excellent Brassica napus parental lines and their 46 and F2 populations. The results showed that silique density （SD） , siliques per plant （SPP） , seeds per silique （SPS） and thousand - seed weight （TSW） exhibited not only additive and dominant effects, but also significant epistatic effects. The dominant effects of all five yield - related traits were obviously greater than their additive effects and epistatic effects. Yield per plant （YPP） showed significant genetic correlation with SD, SPP and SPS, and the main component of the genetic correlation was the dominance correlation. SPP and SPS both showed a significant negative correlation with TSW. The SD of rapeseed was genetically correlated with all three components of yield to a certain extent, and there were different components of genetic effects positively correlated with the three yield components, indicating that SD is a potential trait to reconcile the conflict between TSW and SPP as well as SPS.展开更多
To improve the quality of seedling picking and throwing in the mechanical transplanting process of pepper hole tray seedlings,this study establishes a dynamic model of pepper hole tray seedlings during the picking and...To improve the quality of seedling picking and throwing in the mechanical transplanting process of pepper hole tray seedlings,this study establishes a dynamic model of pepper hole tray seedlings during the picking and throwing stages.Through analyses of the instantaneous force on stem during clamping,substrate force during pulling,and kinematic analysis during throwing,the relationships between stem deviation from cotyledon center and clamping height,picking mechanism rotation speed and clamp opening speed,as well as throwing speed,throwing height,and horizontal throwing displacement are obtained.The main influencing factors affecting throwing success rate and their critical values are determined,with the optimal clamping position found to be 15 mm from the surface of the substrate to the stem.Bench experiments explore the effects of picking mechanism rotation speed,throwing height,and planting mouth diameter on throwing success rate,with the critical ranges of each factor aligning closely with theoretical analysis results,validating the accuracy and feasibility of the model.To investigate the optimal combination of picking and planting mechanisms under conditions of high throwing rate,a response surface experiment analysis is conducted to establish regression mathematical models between major influencing factors and assessment indicators.Experimental results demonstrate that with mechanism rotation speed at 67 r/min,throwing height at 93 mm,and planting mouth diameter at 137 mm,the optimized throwing success rate reaches 94.58%.This study provides valuable insights for improving the throwing quality of pepper hole tray seedlings during transplanting.展开更多
基金supported by the National Key Research and Development Program of China(2023YFD1900802)the China Agriculture Research System of MOF and MARA(CARS-03-19)+2 种基金the National Natural Science Foundation of China(51879267)the Central Public-interest Scientific Institution Basal Research Fund,China(IFI2023-13)the Agricultural Science and Technology Innovation Program(ASTIP),Chinese Academy of Agricultural Sciences。
文摘A high-efficiency mode of high-low seedbed cultivation(HLSC)has been listed as the main agricultural technology to increase land utilization ratio and grain yield in Shandong Province,China.However,limited information is available on the optimized water and nitrogen management for yield formation,especially the grain-filling process,under HLSC mode.A three-year field experiment with four nitrogen rates and three irrigation rates of HLSC was conducted to reveal the response of grain-filling parameters,grain weight percentage of spike weight(GPS),spike moisture content(SMC),and winter wheat yield to water and nitrogen rates.The four nitrogen rates were N1(360 kg ha^(-1) pure N),N2(300 kg ha^(-1) pure N),N3(240 kg ha^(-1) pure N),and N4(180 kg ha^(-1) pure N),respectively,and the three irrigation quotas were W1(120 mm),W2(90 mm),and W3(60 mm),respectively.Results showed that the determinate growth function generally performed well in simulating the temporal dynamics of grain weight(0.989<R^(2)<0.999,where R2 is the determination coefficient).The occurrence time of maximum filling rate(T_(max))and active grain-filling period(AGP)increased with the increase in the water or nitrogen rate,whereas the average grain-filling rate(G_(mean))had a decreasing trend.The final 1,000-grain weight(FTGW)increased and then decreased with the increase in the nitrogen rates and increased with the increase in the irrigation rates.The GPS and SMC had a highly significant quadratic polynomial relationship with grain weight and days after anthesis.Nitrogen,irrigation,and year significantly affected the T_(max),AGP,G_(mean),and FTGW.Particularly,the AGP and FTGW were insignificantly different between high seedbed(HLSC-H)and low seedbed(HLSC-L)across the water and nitrogen levels.Moreover,the moderate water and nitrogen supply was more beneficial for grain yield,as well as for spike number and grain number per hectare.The principal component analysis indicated that combining 240-300 kg N ha^(-1) and 90^(-1)20 mm irrigation quota could improve grain-filling efficiency and yield for the HLSC-cultivated winter wheat.
基金The authors would like to thank the financial support from Central Public-interest Scientific Institution Basal Research Fund(Grant No.Y2019XK18,Y2019PT17-02)Funding for Outstanding Talents of the Ministry of Agriculture of China and the Innovation Project of Chinese Academy of Agricultural Sciences(Grant No.CAAS-ASTIP-2016-AII-02).
文摘Fuji apple(Malus×domestica Borkh.)is a popular fruit cultivar and occupies an important position in the fruit market due to its excellent flavor and storage quality.Ethylene emission can induce respiration,which would reduce postharvest quality and increase storage losses.In order to maintain fruit quality and extend shelf life,apples are usually stored in a low-temperature environment after harvest to reduce the formation of ethylene.Volatile aroma components are regarded as one of the most important aspects of flavor quality and a key factor for apple quality grading and customer satisfaction.Ethylene emission and its relationship with volatile aromas during low temperature,however,have not been determined.In this study,the dynamic changes of volatile aroma compounds of Fuji apples stored at 4°C were detected and analyzed for 42 days.The variation of ethylene released from Fuji apple was studied correspondingly.The results showed that ethyl butyrate,ethyl caproate,ethyl 2-methylbutyrate and 2-methylbutyl acetate were the main aroma components of Fuji apple.The change in ethylene emission and the normalized peak area of volatile aroma compounds exhibited a similar tendency that increased significantly from the 3rd day to the peak on the 14th day and then decreased;there was a positive linear correlation between them with a correlation coefficient of 0.79(P<0.05).Therefore,ethylene release can be used as a potential indicator for evaluation of volatile aroma compounds in apples.Using ethylene emission as an indicator could reduce the difficulty and complexity of volatile aroma evaluation,which could be a new non-destructive inspection choice for apple flavor quality assessment.
基金the financial support for this research from the National High-Tech R&D Program of China (2012AA101404)the National Natural Science Foundation of China (51209208, 51479201)
文摘The ecological effect of reclaimed water irrigation and fertilizer application on the soil environment is receiving more attention.Soil microbial activity and nitrogen（N）levels are important indicators of the effect of reclaimed water irrigation on environment.This study evaluated soil physicochemical properties and microbial community structure in soils irrigated with reclaimed water and receiving varied amounts of N fertilizer.The results indicated that the reclaimed water irrigation increased soil electrical conductivity（EC）and soil water content（SWC）.The N treatment has highly significant effect on the ACE,Chao,Shannon（H）and Coverage indices.Based on a 16S ribosomal RNA（16S rRNA）sequence analysis,the Proteobacteria,Gemmatimonadetes and Bacteroidetes were more abundant in soil irrigated with reclaimed water than in soil irrigated with clean water.Stronger clustering of microbial communities using either clean or reclaimed water for irrigation indicated that the type of irrigation water may have a greater influence on the structure of soil microbial community than N fertilizer treatment.Based on a canonical correspondence analysis（CCA）between the species of soil microbes and the chemical properties of the soil,which indicated that nitrate N（NO3-–-N）and total phosphorus（TP）had significant impact on abundance of Verrucomicrobia and Gemmatimonadetes,meanwhile the p H and organic matter（OM）had impact on abundance of Firmicutes and Actinobacteria significantly.It was beneficial to the improvement of soil bacterial activity and fertility under 120 mg kg^-1 N with reclaimed water irrigation.
基金supported by the National Natural Science Foundation of China(No.31700316)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(Group No.118)+2 种基金the Earmarked Fund for China Agriculture Research System(CARS-12)the Fundamental Research Funds for Central Non-Profit Scientific Institution(1610172018009)Graduate School of Chinese Academy of Agricultural Sciences
文摘Sequence-specific nucleases(SSN) that generate double-stranded DNA breaks(DSBs) in genes of interest are the key to site-specific genome editing in plants. Genome editing has developed into one method of reducing undesirable traits in crops by the induction of knockout mutations. Different SSN-mediated genome-editing systems, including LAGLIDADG homing endonucleases or meganucleases, zinc-finger nucleases, transcription activator-like effector nucleases and clustered regularly interspaced short palindromic repeats, are emerging as robust tools for introducing functional mutations in polyploid crops including citrus, wheat, cotton, soybean, rapeseed, potato, grapes, Camelina sativa,dandelion, and tobacco. The approach utilizes knowledge of biological mechanisms for targeted induction of DSBs and their error-prone repair, allowing highly specific changes at designated genome loci. In this review, we briefly describe genome-editing technologies and their application to genetic improvement of polyploid crops.
基金supported by the National Basic Research Program of China (No. 2005CB120807)the High-Tech Research and Development Program in China(No.2006AA10A102 and No.2006AA10Z1B5)
文摘A dwarf mutant of rice （Oryza sativa L.） by mutagenesis of ethylene methylsulfonate （EMS） treatment from Nipponbare was identified. The mutant exhibited phenotypes of dwarfism and withered leaf tip （dwll）. Based on the intemode length of dwll, this mutant belongs to the dm type of dwarfing. Analysis of elongation of the second sheath and m-amylase activity in endosperm showed that the phenotype caused by dwll was insensitive to gibberellin acid treatment. Using a large F2 population derived from a cross between the dwll and an indica rice variety, TN1, the DWL1 gene was mapped to the terminal region of the long arm of chromosome 3. Fine-mapping delimited it into a 46 kb physical distance between two STS markers, HL921 and HL944, where 6 open reading frames were predicted. Cloning of DWL1 will contribute to dissecting molecular mechanism that regulates plant height in rice, which will be beneficial to molecular assisted selection of this important trait.
基金supported by the Special Fund for Agroscientific Research in the Public Interest,China(201103005)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(2013–2017)
文摘Dissimilatory Fe（Ⅲ） reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe（Ⅱ） species accumulation could indicate the reduction ability. The effects of different green manures on Fe（Ⅲ） reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch （RRV）, rice-rice-rape （RRP）, rice-rice-ryegrass （RRG） and rice-rice-winter fallow （RRF）. Soils were sampled at flowering stage of milk vetch and rape （S1）, before transplantation （S2）, at tillering （S3）, jointing （S4）, and mature （S5） stages of the early rice, and after the harvest of the late rice （S6）. The contents of TFeHa （HCI-extractable total Fe）, Fe（Ⅱ）HCI （HCI-extractable Fe（Ⅱ） species） and Fe（Ⅲ）HCI （HCI- extractable Fe（Ⅲ） species） were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe（Ⅱ）HCI accumulation were investigated. The results showed that TFeHc~ in RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe（II）Ha increased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe（Ⅱ）Ha in RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe（Ⅲ）Ha showed oppositely, and Fe（Ⅱ）HCI/Fe（Ⅲ）HCI performed similarly to Fe（Ⅱ）HCI The maximum accumulation potential of Fe（Ⅱ）HCI was significantly higher in RRF, while the highest maximum reaction rate of Fe（Ⅱ）Ha accumulation appeared in RRG. Significant correlations were found between the indexes of Fe（Ⅱ）HCI accumulation and soil pH, oxidation-reduction potential （Eh） and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHa in red paddy soils, but promoted the ability of Fe（lll） reduction, especially the ryegrass; Fe（Ⅱ）Ha increased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.
基金the financial support of the National Natural Science Foundation of China (41171255)the National Scientific and Technology Program during 12th Five-Year Plan period, China (2012BAD14B02)
文摘Seven inorganic amendment materials were added into arsenic （As） contaminated soil at a rate of 0.5% （w/w）; the materials used were sepiolite, red mud, iron grit, phosphogypsum, ferrihydrite, iron phosphate, and layered double oxides （LDO）. Plant growth trials using rape （edible rape, Brassia campestris L.） as a bio-indicator are commonly used to assess As bio- availability in soils. In this study, B. campestris was grown in a contaminated soil for 50 days. All of the inorganic amend- ments significantly inhibited the uptake of As by B. campestris. Following soil treatment with the seven aforementioned inorganic ammendments, the As concentrations in the edible parts of B. campestris were reduced by 28.6, 10.5, 8.7, 31.0, 47.4, 25.3, and 28.8%, respectively, as compared with the plants grown in control soil. The most effective amendment was ferdhydrite, which reduced As concentration in B. campestris from 1.84 to 0.97 mg kg-~, compared to control. Furthermore, ferrihydrite-treated soils had a remarkable decrease in both non-specifically sorbed As and available-As by 67 and 20%, respectively, comparing to control. Phosphogypsum was the most cost-effective amendment and it showed excellent performance in reducing the water soluble As in soils by 31% and inhibiting As uptake in B. campestris by 21% comparing to control. Additionally, obvious differences in As transfer rates were observed in the various amendments. The seven amendment materials used in this study all showed potential reduction of As bioavailability and influence on plant growth and other biological processes still need to be further explored in the long term.
基金supported by the Natural Science Foundation of Hebei (C2020204028)the National Natural Science Foundation of China (31501623)。
文摘Thaumatin-like protein (TLP) plays an important role in combating plant pathogen infection.Common root rot caused by Bipolaris sorokiniana and leaf rust caused by Puccinia triticina (Pt) are major fungal diseases in wheat.The disease responses of TaTLP1-overexpressing transgenic lines (TaTLP1-OE) were evaluated after inoculation with each pathogen.The TaTLP1-OE lines had no apparent differences in tiller number and 1000-kernel weight from the wild type Jinan Wheat No.1 (JW1),whereas resistance to leaf rust and common root rot was improved,resulting from activated peroxidase and b-1,3-glucanase after B.sorokiniana infection,and reactive oxygen species-related genes were upregulated in Ta TLP1-OE lines after Pt infection.These results indicated that stable expression of TaTLP1 increased resistance against both diseases.
基金the Special National Key Research and Development Plan[grant number 2016YFD0400204]the Ministry of Science and Technology of the People’s Republic of China[grant number2015FY111300]the Technology Innovation Program of the Chinese Academy of Agricultural Sciences[grant number CAAS-ASTIP-201X-IAPPST].
文摘One of the main food crops in the world,rice can accumulate high levels of arsenic from flooded paddy soils,which seriously threatens human health.Soaking,a common processing method for brown rice products,especially for brown rice noodles,was investigated in this study.Japonica rice(Dao Hua Xiang No.2)and Indica rice(Ye Xiang You No.3)were selected for studying the effects of soaking on arsenic concentrations,species,and distributions.Results revealed that soaking can efficiently remove arsenic in these two rice varieties,and the main part of removal is endosperm with the maximal rate of about 40%.Inorganic arsenic(I-As)(about 85%)is the main species of arsenic reduction.Meanwhile,the variations of four other elements(i.e.,Mg,Ca,Zn,and Fe)were analyzed.Collectively,the findings of this study indicate that soaking can efficiently remove arsenic in brown rice under controlled soaking conditions,which thereby reduces the arsenic intake for brown rice customers.
基金funded by the earmarked fund for China Agriculture Research System(CARS-03-19)the National Natural Science Foundation of China(51879267 and 51709264)+1 种基金the Open Fund Projects of the Agricultural Environment Experimental Station of Minstry of Agriculture and Rural Affairs,China(FIRI2021040103)the Agricultural Science and Technology Innovation Program(ASTIP)of Chinese Academy of Agricultural Sciences。
文摘Excessive application of nitrogen (N) fertilizer is the main cause of N loss and poor use efficiency in winter wheat (Triticum aestivum L.) production in the North China Plain (NCP).Drip fertigation is considered to be an effective method for improving N use efficiency and reducing losses,while the performance of drip fertigation in winter wheat is limited by poor N scheduling.A two-year field experiment was conducted to evaluate the growth,development and yield of drip-fertigated winter wheat under different split urea (46%N,240 kg ha^(-1)) applications.The six treatments consisted of five fertigation N application scheduling programs and one slow-release fertilizer (SRF) application.The five N scheduling treatments were N0–100 (0%at sowing and 100%at jointing/booting),N25–75 (25%at sowing and 75%at jointing and booting),N50–50(50%at sowing and 50%at jointing/booting),N75–25 (75%at sowing and 25 at jointing/booting),and N100–0 (100%at sowing and 0%at jointing/booting).The SRF (43%N,240 kg ha^(-1)) was only used as fertilizer at sowing.Split N application significantly (P<0.05) affected wheat grain yield,yield components,aboveground biomass (ABM),water use efficiency(WUE) and nitrogen partial factor productivity (NPFP).The N50–50 and SRF treatments respectively had the highest yield(8.84 and 8.85 t ha^(-1)),ABM (20.67 and 20.83 t ha^(-1)),WUE (2.28 and 2.17 kg m^(-3)) and NPFP (36.82 and 36.88 kg kg^(-1)).This work provided substantial evidence that urea-N applied in equal splits between basal and topdressing doses compete economically with the highly expensive SRF for fertilization of winter wheat crops.Although the single-dose SRF could reduce labor costs involved with the traditional method of manual spreading,the drip fertigation system used in this study with the N50–50 treatment provides an option for farmers to maintain wheat production in the NCP.
基金the National Natural Science Foundation of China(31270734)the earmarked fund for China Agricultural Research System(CARS-19)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2014-TRICAAS).
文摘In response to preharvest priming with exogenous methyl jasmonate(MeJA),tea plants adjust their physiological behavior at the molecular level.The whole-organism reconfiguration of aroma formation from the precursor to storage is poorly understood.In this study,we performed iTRAQ proteomic analysis and identified 337,246,and 413 differentially expressed proteins in tea leaves primed with MeJA for 12 h,24h,and 48 h,respectively.Furthermore,a total of 266 nonvolatile and 100 volatile differential metabolites were identified by utilizing MS-based metabolomics.A novel approach that incorporated the integration of extended self-organizing map-based dimensionality was applied.The vivid time-scale changes tracing physiological responses in MeJA-primed tea leaves are marked in these maps.Jasmonates responded quickly to the activation of the jasmonic acid pathway in tea leaves,while hydroxyl and glycosyl jasmonates were biosynthesized simultaneously on a massive scale to compensate for the exhausted defense.The levels ofα-linolenic acid,geranyl diphosphate,farnesyl diphosphate,geranylgeranyl diphosphate,and phenylalanine,which are crucial aroma precursors,were found to be significantly changed in MeJA-primed tea leaves.Green leaf volatiles,volatile terpenoids,and volatile phenylpropanoids/benzenoids were spontaneously biosynthesized from responding precursors and subsequently converted to their corresponding glycosidic forms,which can be stably stored in tea leaves.This study elucidated the physiological response of tea leaves primed with exogenous methyl jasmonate and revealed the molecular basis of source and sink changes on tea aroma biosynthesis and catabolism in response to exogenous stimuli.The results significantly enhance our comprehensive understanding of tea plant responses to exogenous treatment and will lead to the development of promising biotechnologies to improve fresh tea leaf quality.
基金National Nonprofit Institute Research Grant (Graduate School of Chinese Academy of Agricultural Sciences,2009)
文摘This article conducts empirical analysis of rice growers' behavior of productive capital input and the influencing factors,using the input-output survey data concerning rice growing by 305 peasant households in 2009 in Huanan County and Huachuan County,Jiamusi City,Heilongjiang Province.I use Logit model to carry out econometric test of factors influencing the possibility of fixed productive investment.The test results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level,peasant households' expectation of the minimum purchase price of rice,have significant effect on whether to conduct fixed productive investment,whether there are disasters has no significant effect on the scale of peasant households' productive investment.Then I use Tobit model to carry out econometric test of factors influencing the scale of productive capital input.The results show that family size,the proportion of non-agricultural employment,the average educational level of households,farmland area,household farming income,credit level and family housing value,peasant households' expectation of the minimum purchase price of rice,whether there are disasters,have significant effect on the scale of peasant households' productive investment.On the basis of model test results,in order to promote the rice growers to increase fixed productive input and increase productive capital input,rational recommendations are put forward as follows:raising the minimum purchase price of rice,scaling up rice growing,making every effort to promote the educational level of rice growers,ensuring that the rice growers obtain productive capital input loans timely.
基金supported by the National Basic Research Program of China (2009CB11900)the Special Fund for Agro-Scientific Research in the Public Interest, China (201003065)
文摘MicroRNAs （miRNAs） are -21 nucleotide （nt）, endogenous RNAs that regulate gene expression in plants. Increasing evidence suggests that miRNAs play an important role in species-specific development in plants. However, the detailed miRNA profile divergence has not been performed among tomato species. In this study, the small RNA （sRNA） profiles of Solanum lycopersicum cultivar 9706 and Solanum habrochaites species PI 134417 were obtained by deep sequencing. Sixty-three known miRNA families were identified from these two species, of which 39 were common. Further miRNA profile comparison showed that 24 known non-conserved miRNA families were species-specific between these two tomato species. In addition, six conserved miRNA families displayed an apparent divergent expression pattern between the two tomato species. Our results suggested that species-specific, non-conserved miRNAs and divergent expression of conserved miRNAs might contribute to developmental changes and phenotypic variation between the two tomato species. Twenty new miRNAs were also identified in S. lycopersicum. This research significantly increases the number of known miRNA families in tomato and provides the first set of small RNAs in S. habrochaites. It also suggests that miRNAs have an important role in species-specific plant developmental regulation.
文摘Rice yield is still low in Nigeria despite the ecological advantages. Several challenges has been traced it production. The study intend to investigate if other rice producing nations are faced with similar challenges and at what magnitude and more importantly, what can be learn to improve the rice yield in Nigeria. Based on 2013/2014 survey, a total sample of 400 famers were randomly interviewed;164 from Niger State of Nigeria and 236 from Hainan province of China. The study collate the perception of farmers to rice production constraints categorized into biotic, abiotic and socioeconomics. Biplot analysis was employed to examine multivariate pattern of their perceptions towards production constraints. The multivariate technique simultaneously displaying different yield levels and factor constraints in data matrix providing the inter-unit distances, variance and correlations of variables. According to the study, Niger state farmers identified socioeconomic constraint as the major factors to production and attributed it to lack of or insufficient investment while the Hainan farmers majorly identified abiotic constraints. The study also indicated that great potential remain to further improve rice yield in both regions especially in Nigeria given the appropriate investment on essential inputs. This study is of great use to extension officers more so, given the investment in Africa, policy makers take advantage of the bilateral and multilateral relationship to invest ease transfer of agricultural information and technologies between or among partners.
基金supported by the Zhejiang Province Natural Science Foundation(LR23C160002)the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2023-TRICAAS)the National Natural Science Foundation(32172630 and 31972467).
文摘Diabetes mellitus(DM)is a pressing global public health issue with a high incidence of morbidity and mortality due to its complications.Although there are many medicines available for the treatment of DM,long-term use causes various adverse effects,such as diarrhea,vomiting,and nausea.Tea,owing to its richness of diverse bioactive components including tea polyphenols,tea polysaccharides,and alkaloids,has displayed promising antidiabetic properties.Screening antidiabetic bioactive compounds derived from teas is receiving increasing attention.Epidemiological and clinical investigations have demonstrated an inverse relationship between tea consumption and the incidence of DM.Both in vitro and in vivo experiments have substantiated the hypoglycemic effects of tea and its bioactive components through several possible mechanisms,including improvement of insulin resistance,inhibition of carbohydrates digestion and absorption(inhibitα-amylase andα-glucosidase activity),regulations of gut microbiota,inflammatory cytokines,and gene and protein expressions in the insulin signaling pathway,as well as amelioration of DM complications.This comprehensive review provides an up-to-date overview of the hypoglycemic properties associated with tea and its bioactive components.It also delves into their potential mechanisms,offering a theoretical foundation for further research into tea's antidiabetic properties and for the development of innovative antidiabetic functional products.
基金the National Natural Science Foundation of China(31470693,31100503)the Natural Science Foundation of Zhejiang Province(LY18C160006)+2 种基金the Central Public-interest Scientific Institution Basal Research Fund(1610212018004,1610212016017)the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2014-TRICAAS)the Key Project of International Science&Technology Cooperation,National Key Research and Development Program of China(2017YFE0107500).
文摘Diterpenes are the most complex and abundant plant metabolites,some of which play significant roles in both primary and secondary metabolism.Ent-kaurene synthase is the key enzyme for gibberellins(GAs)biosynthesis,which may act as a catalyst in the formation of entkaurene,the precursor for GAs,by cyclization or rearrangement of the substrate ent-copalyl diphosphate(ent-CPP).Ilex latifolia Thunb(Aquifoliaceae)is a widely distributed Chinese plant whose leaves are used to process a popular Chinese bitter tea named'Kudingcha',which has anti-microbial,anti-oxidant and anti-inflammatory properties.Here,we isolated a diterpene synthase gene from the leaf transcriptome of I.latifolia,and further identified its biosynthesis activity by in vitro enzymatic testing.The heterologous expressed ent-kaurene synthase of I.latifolia(IlKS)in E.coli could catalyze ent-copalyl diphosphate(ent-CPP)to form ent-kaurene.Tissue-specific expression indicated that IlKS had the highest transcript level in roots which is maybe the major location of ent-kaurene biosynthesis.This study would help us to determine diterpenoid metabolism and GAs biosynthesis in I.latifolia,to better understand the regulation function of GAs in growth and development.
基金This work was supported by the National Natural Science Foundation of China(31872140,31470693,31100503)the Natural Science Foundation of Zhejiang Province(LY18C160006)+1 种基金the Zhejiang Provincial Key Laboratory of Characteristic Aquatic Vegetable Breeding and Cultivation Open Fund Project(KL-2022-01,KL-2022-02)the Project for Science and Technology in Jinhua City(Grant No.2019-2-002).The authors thank TopEdit(www.topeditsci.com)for its linguistic assistance during the preparation of this manuscript.
文摘Nymphaea is a key genus of the ANA grade(Amborellales,Nymphaeales,and Austrobaileyales)of basal flowering plants,which serve as a key model to study the early evolution of floral traits.In this study,we comprehensively investigated the emission,biosynthesis,and biological function of the floral scent in a night-blossoming waterlily Nymphaea prolifera.The headspace volatile collection combined with GC-MS analysis showed that the floral scent of N.prolifera is predominately comprised by methylated benzenoids including anisole,veratrole,guaiacol,and methoxyanisole.Moreover,the emission of these floral benzenoids in N.prolifera exhibited temporal and spatial pattern with circadian rhythm and tissue specificity.By creating and mining transcriptomes of N.prolifera flowers,12 oxygen methyltransferases(NpOMTs)were functionally identified.By in vitro enzymatic assay,NpOMT3,6,and 7 could produce anisole and NpOMT5,7,9,produce guaiacol,whereas NpOMT3,6,9,11 catalyzed the formation of veratrole.Methoxyanisole was identified as the universal product of all NpOMTs.Expression patterns of NpOMTs provided implication for their roles in the production of the respective benzenoids.Phylogenetic analysis of OMTs suggested a Nymphaea-specific expansion of the OMT family,indicating the evolution of lineage-specific functions.In bioassays,anisole,veratrole,and guaiacol in the floral benzenoids were revealed to play the critical role in repelling waterlily aphids.Overall,this study indicates that the basal flowering plant N.prolifera has evolved a diversity and complexity of OMT genes for the biosynthesis of methylated benzenoids that can repel insects from feeding the flowers.These findings provide new insights into the evolutional mechanism and ecological significance of the floral scent from early-diverged flowering plants.
基金supported by the National Key Research and Development Program of China(No.2016YFD0101300)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(Group No.118)+1 种基金the Earmarked Fund for China Agriculture Research System(CARS-12)Hubei Agricultural Science and Technology Innovation Center(201620000001048)
文摘Effective silique number per plant(ESN), seeds per silique(SS), thousand seeds weight(TSW), silique length(SL) and silique density(SD) are important seed yield potential determinant traits in rapeseed(Brassica napus L.), which are controlled by quantitative trait loci(QTL). Mapping QTL to delimited chromosomal region offers an effective method for genetic dissection of these traits. A set of 96 double haploid(DH) lines were developed by crossing 2 Brassica napus lines R1 and R2, and an immortalized F_2(IF_2) population containing 124 combinations was developed by crossing those DH lines. DH populations were planted at 2 locations for 2 years and IF_2 populations were planted in 2 locations for 1 year. Based on the established 2,217.2 cM length high density genetic map, 42 QTLs were identified, with 26 QTLs detected repeatedly in different environments or populations, including 8 for SL, 7 for TSW, 4 for ESN, 4 for SS and 3 for SD. Among these identified QTLs, 3, 4, 1, 1 and 3 QTLs were considered as major QTLs for SL, TSW, ESN, SS and SD, respectively. In addition, 2 QTLs on A9 chromosome which control multiple traits were identified. These results warrant further study of fine mapping for yield and yield components.
基金This research was supported by the National Basic Research Program of China （ 973 Program, 2011CB109302）；the National High - Tech R＆D Pro-gram of China （863 Program, 2011AA10A104, 2012AA101107） ； Natural Science Foundation of Hu-bei Province （2015CFA103） ； Hubei Agricultural Science and Technology Innovation Center.
文摘To provide a theoretical basis for further improvement of Brassica napus yield, additive dominance with additive - by - additive epistatic effects （ ADAA） genetic model and a 6 X 8 partial dial- lel cross design were used to analyze the genetic effects and correlations of five yield related traits of 14 excellent Brassica napus parental lines and their 46 and F2 populations. The results showed that silique density （SD） , siliques per plant （SPP） , seeds per silique （SPS） and thousand - seed weight （TSW） exhibited not only additive and dominant effects, but also significant epistatic effects. The dominant effects of all five yield - related traits were obviously greater than their additive effects and epistatic effects. Yield per plant （YPP） showed significant genetic correlation with SD, SPP and SPS, and the main component of the genetic correlation was the dominance correlation. SPP and SPS both showed a significant negative correlation with TSW. The SD of rapeseed was genetically correlated with all three components of yield to a certain extent, and there were different components of genetic effects positively correlated with the three yield components, indicating that SD is a potential trait to reconcile the conflict between TSW and SPP as well as SPS.
基金supported in part by the Innovation Engineering of the Chinese Academy of Agricultural Sciences.
文摘To improve the quality of seedling picking and throwing in the mechanical transplanting process of pepper hole tray seedlings,this study establishes a dynamic model of pepper hole tray seedlings during the picking and throwing stages.Through analyses of the instantaneous force on stem during clamping,substrate force during pulling,and kinematic analysis during throwing,the relationships between stem deviation from cotyledon center and clamping height,picking mechanism rotation speed and clamp opening speed,as well as throwing speed,throwing height,and horizontal throwing displacement are obtained.The main influencing factors affecting throwing success rate and their critical values are determined,with the optimal clamping position found to be 15 mm from the surface of the substrate to the stem.Bench experiments explore the effects of picking mechanism rotation speed,throwing height,and planting mouth diameter on throwing success rate,with the critical ranges of each factor aligning closely with theoretical analysis results,validating the accuracy and feasibility of the model.To investigate the optimal combination of picking and planting mechanisms under conditions of high throwing rate,a response surface experiment analysis is conducted to establish regression mathematical models between major influencing factors and assessment indicators.Experimental results demonstrate that with mechanism rotation speed at 67 r/min,throwing height at 93 mm,and planting mouth diameter at 137 mm,the optimized throwing success rate reaches 94.58%.This study provides valuable insights for improving the throwing quality of pepper hole tray seedlings during transplanting.
