摘要
【目的】通过对比不同柠檬品种低镁胁迫和正常供镁条件下植株矿质养分含量以及果实产量和品质的差异,筛选出耐缺镁的品种,为柠檬品种布局和养分管理提供理论依据。【方法】以费米耐劳、云柠一号、塔西提3个主栽的柠檬品种为材料,用沙培的方式分别在镁缺乏(0 mg·L^(-1))、镁不足(6 mg·L^(-1))、镁正常(24 mg·L^(-1))供应下进行培养。【结果】低镁胁迫下不同柠檬品种各器官的镁含量都减少,以费米耐劳的叶片和根、云柠一号的果实、塔西提的茎下降幅度最大,分别为30.0%、44.0%、21.1%、26.9%。低镁胁迫时3个柠檬品种地下部分矿质养分含量的变化规律相同,但在地上部分差异较大,低镁胁迫下各器官的磷、钾、钙、锰的含量整体为上升趋势,果实、茎和根部锌含量则显著下降,不同品种铜、铁含量在各器官中的变化规律不一致。在低镁胁迫时果实外在品质变化较小,但出汁率及可溶性固形物、总酸、维生素C含量显著下降,各品种受低镁胁迫影响的幅度表现为:塔西提>云柠一号>费米耐劳。低镁胁迫下果实可溶性固形物、总酸和维生素C含量与镁含量呈显著正相关,与钾、钙、锰含量呈显著负相关。低镁胁迫下,柠檬单株挂果数和产量都显著下降,云柠一号下降幅度最大,镁缺乏和镁不足时单株挂果数分别减少67.62%和44.14%,单株产量分别减少67.07%和46.17%,塔西提下降幅度最小,塔西提果实的镁携出量显著低于其他品种。【结论】低镁胁迫下,在3个品种中,塔西提镁含量下降幅度、减产幅度、果实的镁携出量以及对其他元素的影响都是最小的,较其他品种耐镁缺乏。
【Objective】The soil type in the south of China is mainly red soil,and magnesium(Mg)deficiency is a common problem in citrus production.Mg deficiency leads to the decrease of fruit yield and quality in lemon-producing areas of Yunnan province.Different lemon varieties have various characteristics of tolerance to Mg deficiency.In this study,the variety that could tolerate Mg deficiency was screened out by comparing the response of mineral nutrient contents in various organs,yield,and fruit quality to low Mg supply in different lemon varieties.Hopefully,the study will provide a theoretical basis for the proper lemon cultivar regionization and fertilization management.【Methods】The grafted seedlings were selected from three main lemon varieties,Femminello,Yunning No.1 and Tahiti,which were relatively uniform in stem thickness and height,and grew well.After the attached soil was washed out and main roots were pruned,the grafted lemon seedlings were transplanted into a plastic pot filled with 28 kg of silver sand,and cultivated in a greenhouse.And then,the seedlings were supplied with distilled water only,and watered with 1/2 concentration of Hoagland's nutrient solution and Mg-free Aron’s full concentration nutrient solution at the stage of shoot growing.Mg nutrient gradient stress was carried out when 7-8 new leaves emerged,and the treated period was one year.Three Mg concentration gradients were set for each lemon variety,which were deficient magnesium(Mg0:0 mg·L^(-1)),insufficient magnesium(Mg6:6 mg·L_(-1))and normal magnesium level(Mg24:24 mg·L^(-1)).There were three biological repetitions for each treatment with five plants in each repetition.At the end of the pot trial experiment,the mineral nutrient contents including nitrogen,phosphorus,potassium,zinc,iron,manganese,copper,calcium,and magnesium in root,stem,leaf and fruit were determined,and the fruit quality including fruit size,TSS,total acid content,and vitamin C contents was determined.【Results】Under low magnesium stress,the highest declines of Mg contents presented in the leaves and roots of Femminello,the fruits of Yunning No.1 and the stems of Tahiti,which were 29.96%,43.97%,21.13%,and 26.87%,respectively.With the same Mg concentration treatment,the Mg content in the leaves of Yunning No.1 was significantly higher than that of two other varieties,while the Mg content in the stem of Tahiti was significantly higher than that of two other varieties,and the Mg content of the fruit was as follows:Yunning No.1>Femminello>Tahiti.Under low magnesium stress,the trend of mineral nutrient changed in a similar way as underground parts of different lemon varieties,but there were differences in the aboveground parts.The contents of P,K,Ca,Mn in various parts of the lemon plants increased under the low magnesium stress conditions,and the contents of Zn in fruit,stem and root decreased significantly.The contents of copper and iron varied in various parts of different lemon varieties.The external fruit quality was almost unaltered,but the juice yield,total soluble solid,total acid and vitamin C contents decreased significantly under low magnesium stress conditions.The effect of low magnesium stress on different varieties was as follows:Tahiti>Yunning No.1>Femminello.The total soluble solid,total acid,and vitamin C contents in the fruit were significantly correlated with Mg content,which were significantly negatively correlated with K,Ca and Mn contents.Under low magnesium stress conditions,the fruit number and the yield per plant decreased significantly,with Yunning No.1 decreasing the most,the treatments of Mg deficiency and Mg insufficiency decreasing by 67.62% and 44.14% regarding fruit number,respectively,and decreasing by 67.07% and 46.17% regarding yield,respectively,while Tahiti declined the least.Difference in magnesium content and individual plant yield between treatments resulted in significant difference in the amount of magnesium contained in the fruit.Under the condition of normal magnesium content,the fruit yield,Mg content,and Mg load of Yunning No.1 were significantly higher than two other varieties,and it required more Mg to maintain normal growth of lemon,resulting in greater sensitivity to Mg deficiency.Under low Mg conditions,there was no significant difference in yield between Tahiti and two other varieties,but its Mg content and fruit’s Mg load were significantly lower than those of two other varieties,As a result,magnesium-requiring amount was less than two other varieties,showing certain tolerance to Mg deficiency.【Conclusion】In summary,low magnesium stress displayed the least decrease of magnesium content and yield reduction and influence on other elements in Tahiti.These results suggested that Tahiti was the most resistant to magnesium deficiency among the three varieties.Thus lemon varieties like Tahiti should be chosen to plant in areas with severe Mg deficiency.It is also important to make reasonable Mg fertilizer supply in each growing area with different varieties.
作者
杜玉霞
李晶
寸待泽
朱春华
刘航秀
李丹萍
李进学
DU Yuxia;LI Jing;CUN Daize;ZHU Chunhua;LIU Hangxiu;LI Danping;LI Jinxue(Institute of Tropical and Subtropical Cash Crops,Yunnan Academy of Agricultural Sciences,Baoshan 678000,Yunnan,China)
出处
《果树学报》
CAS
CSCD
北大核心
2021年第8期1330-1339,共10页
Journal of Fruit Science
基金
国家自然科学基金(32060653)
云南省基础研究计划(2019FD080)
现代农业(柑橘)产业技术体系柠檬综合试验站建设专项(CARS-26)
中国工程院院地合作项目(2019YNZH2)
云南省重大科技专项(2019ZG002)
科技部国家重点研发计划(2019YFD1001400)。
关键词
柠檬
低镁胁迫
矿质养分
果实品质
Lemon
Low magnesium stress
Mineral nutrient content
Fruit quality
