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
Liming is a common strategy applied to attain optimal pH for tea growth in severely acidic soils.Tea however is a calciphobous plant,and the effects of liming on its growth and nutrient uptake remain poorly understand...Liming is a common strategy applied to attain optimal pH for tea growth in severely acidic soils.Tea however is a calciphobous plant,and the effects of liming on its growth and nutrient uptake remain poorly understand.Therefore,it is necessary to better understand the effects of liming on soil chemical properties and tea nutrient content.In this study,a tea plantation that had exhibited large variation in growth after liming was selected as a study site.We categorized plots into two growth condition groups:Plot 1(poor growth)and Plot 2(excellent growth).Tea nutrient levels,and soil chemical properties were then compared between the two groups.Normalized difference vegetation index(NDVI)and transformed vegetation index(TVI)values were significantly higher and lower,respectively,in Plot 2 than in Plot 1.Yield,number of buds per m2,and 100-bud weight were significantly higher in Plot 2.These results were attributed to higher N,K,and Al concentrations and lower Ca concentrations in leaves,and lower pH and available Ca and higher available Al in soil.Leaf concentrations of K and Al were significantly negatively correlated with leaf concentrations of Ca and soil pH.A positive relationship was observed between leaf concentrations of K and Al,indicating inhibited K and Al uptake due to over-liming,restricting tea growth.In conclusion,our results show that tea growth will be restricted by over-liming,as a result of the high soil pH and Ca concentration inhibiting the K and Al uptake.展开更多
The tea yield estimation provides information support for the harvest time and amount and serves as a decision-making basis for farmer management and picking.However,the manual counting of tea buds is troublesome and ...The tea yield estimation provides information support for the harvest time and amount and serves as a decision-making basis for farmer management and picking.However,the manual counting of tea buds is troublesome and inefficient.To improve the efficiency of tea yield estimation,this study presents a deep-learning-based approach for efficiently estimating tea yield by counting tea buds in the field using an enhanced YOLOv5 model with the Squeeze and Excitation Network.This method combines the Hungarian matching and Kalman filtering algorithms to achieve accurate and reliable tea bud counting.The effectiveness of the proposed model was demonstrated by its mean average precision of 91.88%on the test dataset,indicating that it is highly accurate at detecting tea buds.The model application to the tea bud counting trials reveals that the counting results from test videos are highly correlated with the manual counting results(R^(2)=0.98),indicating that the counting method has high accuracy and effectiveness.In conclusion,the proposed method can realize tea bud detection and counting in natural light and provides data and technical support for rapid tea bud acquisition.展开更多
Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are cruci...Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.展开更多
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the National Key R and D Program of China(2020YFD1000701)the Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2014-TRICAAS)the Funds for Science and Technology Innovation Project from the Chinese Academy of Agricultural Sciences(CAASXTCX2016015).
文摘Liming is a common strategy applied to attain optimal pH for tea growth in severely acidic soils.Tea however is a calciphobous plant,and the effects of liming on its growth and nutrient uptake remain poorly understand.Therefore,it is necessary to better understand the effects of liming on soil chemical properties and tea nutrient content.In this study,a tea plantation that had exhibited large variation in growth after liming was selected as a study site.We categorized plots into two growth condition groups:Plot 1(poor growth)and Plot 2(excellent growth).Tea nutrient levels,and soil chemical properties were then compared between the two groups.Normalized difference vegetation index(NDVI)and transformed vegetation index(TVI)values were significantly higher and lower,respectively,in Plot 2 than in Plot 1.Yield,number of buds per m2,and 100-bud weight were significantly higher in Plot 2.These results were attributed to higher N,K,and Al concentrations and lower Ca concentrations in leaves,and lower pH and available Ca and higher available Al in soil.Leaf concentrations of K and Al were significantly negatively correlated with leaf concentrations of Ca and soil pH.A positive relationship was observed between leaf concentrations of K and Al,indicating inhibited K and Al uptake due to over-liming,restricting tea growth.In conclusion,our results show that tea growth will be restricted by over-liming,as a result of the high soil pH and Ca concentration inhibiting the K and Al uptake.
基金supported by Zhejiang Provincial Natural Science Foundation of China under grant no.LTGN23C130004the Central Public-Interest Scientific Institution Basal Research Fund(1610212021004 and 1610212022004)+1 种基金the Key R&D Program of Zhejiang(2022C02010 and 2022C02052)Scientific Research Foundation of Zhejiang A and F University(2020FR063).
文摘The tea yield estimation provides information support for the harvest time and amount and serves as a decision-making basis for farmer management and picking.However,the manual counting of tea buds is troublesome and inefficient.To improve the efficiency of tea yield estimation,this study presents a deep-learning-based approach for efficiently estimating tea yield by counting tea buds in the field using an enhanced YOLOv5 model with the Squeeze and Excitation Network.This method combines the Hungarian matching and Kalman filtering algorithms to achieve accurate and reliable tea bud counting.The effectiveness of the proposed model was demonstrated by its mean average precision of 91.88%on the test dataset,indicating that it is highly accurate at detecting tea buds.The model application to the tea bud counting trials reveals that the counting results from test videos are highly correlated with the manual counting results(R^(2)=0.98),indicating that the counting method has high accuracy and effectiveness.In conclusion,the proposed method can realize tea bud detection and counting in natural light and provides data and technical support for rapid tea bud acquisition.
基金supported by the earmarked fund for the Modern Agro-Industry Technology Research System (No.CARS-19)the Innovative Research Team in Chinese Academy of Agricultural Sciences (No.CAAS ASTIP-2014-TRICAAS).
文摘Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology.
