摘要
【目的】明确不同温度和氮形态营养条件下荔枝根系吸收K^(+)、Ca^(2+)和Mg^(2+)能力的差异。【方法】以黑叶荔枝实生苗为材料,进行水培实验。设置6个温度处理(10、15、20、25、30和35℃)和3种氮营养形态处理(硝态氮、1/2硝态氮+1/2铵态氮和铵态氮)。研究荔枝吸收K^(+)、Ca^(2+)和Mg^(2+)养分离子的动力学参数(最大吸收速率Imax、亲和力Am和离子补偿点Cmin)变化,比较根系吸收营养能力的差异。【结果】除温度与氮营养的交互作用对荔枝吸收Ca^(2+)的Am无显著影响外,温度、氮营养及两者的交互作用对荔枝吸收K^(+)、Ca^(2+)和Mg^(2+)均有显著影响(p<0.05)。硝态氮和1/2硝+1/2铵处理下荔枝吸收K^(+)的3个动力学参数随温度升高而波动变化,而铵态氮处理下动力学参数随温度升高变化不大。硝态氮处理下荔枝吸收Ca^(2+)的Imax随温度升高而提高,其他营养下随温度升高而波动变化;荔枝吸收Ca^(2+)的Am均随温度升高而先降低后提高,而Cmin随温度及氮营养变化的趋势与Am的相反。不同氮营养下荔枝对Mg^(2+)的动力学参数随温度的升高而波动变化。【结论】在秋梢生长和果实膨大期,硝铵混合氮源比单一形态氮源更有利于荔枝对钾、钙和镁营养的吸收。在秋梢老熟期至开花前可以叶面喷施钙肥和镁肥为荔枝补充钙和镁营养。
【Objective】K,Ca and Mg uptake by litchi under varied temperatures and N forms was investigated,aiming to provide references by selecting suitable N source and K,Ca and Mg nutrient combinations for litchi in different seasons or phenological stages.【Methods】A hydroponic experiment was conducted using litchi seedlings of cultivar Heiye.The designed growth temperatures were 10,15,20,25,30 and 35℃,and the supplied N forms included nitrate,1/2 nitrate+1/2 ammonium,and ammonium.K,Ca and Mg contents in the nutrient solution were measured,and the uptake kinetic parameters of K,Ca and Mg nutrients were determined.【Results】Except that the interaction between temperature and nitrogen nutrition had no significant effect on affinity(Am)of Ca^(2+)absorbed by litchi,temperature,nitrogen form and their interaction had significant effects on the absorption of K^(+),Ca^(2+)and Mg^(2+)(p<0.05).Under the conditions of nitrate and 1/2 nitrate+1/2 ammonium,the kinetic parameters of litchi on K^(+)fluctuated with temperature increased,while under ammonium nitrogen treatment,the kinetic parameters did not change significantly as temperature increased.The maximum absorption rate(Imax)of K^(+)by litchi at 10,15 and 30℃was found in the treatment of 1/2 nitrate+1/2 ammonium,which had a significantly higher Imax of K^(+)than the other two treatments.Under the ammonium treatment at 10 and 15℃,Imax was significantly higher than under nitrate treatment,but the opposite was found at 30℃.There was no significant difference in Imax among the three nitrogen treatments at the other temperatures.Under ammonium treatment,the Am of K^(+)absorbed by litchi always had the maximum value at different temperatures.At 15 and 30℃,the Am in the treatment of 1/2 nitrate+1/2 ammonium was greater than that in the nitrate treatment.However,that in the nitrate treatment was larger at 25℃.Under different temperatures,ion compensation concentrations(Cmin)of K^(+)uptake by litchi was always the highest under the nitrate treatment,with the excep
作者
朱陆伟
周昌敏
白翠华
姚丽贤
ZHU Luwei;ZHOU Changmin;BAI Cuihua;YAO Lixian(College of Natural Resources and Environment,South China Agricultural University,Guangzhou 510642,Guangdong,China)
出处
《果树学报》
CAS
CSCD
北大核心
2021年第4期538-548,共11页
Journal of Fruit Science
基金
国家现代农业产业技术体系建设专项(CARS-32)。
关键词
荔枝
温度
硝态氮
铵态氮
动力学参数
Litchi
Temperature
Nitrate
Ammonium
Kinetic parameters
