摘要
6个有代表性的甜莱品种在人工气候室的营养液培养试验表明,甜菜子叶期幼苗对NO_3^-的吸收要经最初2h的适应阶段后才可均匀进行。均匀吸收后,观察到多倍体的吸收量>2倍体,倍性相同品种中E型>NE型>NZ型>Z型的初步结果。不同类型品种间NO_3^-吸收的表观米氏常数(Km,app)、最大吸收速率(Im)有明显差异,除多倍体NZ型品种甜研301的Km,app较低而Im较高外,其余品种的Km,app和Im呈正相关。品种间溢泌液体积、溢泌液中NO_3^-量以及NO_3^-上运速率与品种间Im值的排序一致,NRA的体内测定表明,未经NO_3^-诱导的供试品种子叶的NRA无差异。经NO_3^-诱导的,无论反应液中是否加NO_3^-,子叶NRA在不同类型品种间差异显著,子叶NRA与NO_3^-吸收量、NO_3^-上运速率呈极显著正相关。文中还讨论了上述生理生化指标对考察甜菜种质资源的氮素利用性能和选育氮素利用率高的品种的参考价值。
Nutrient solution culture showed that sugar beet seedlings at cotyledon stage began to consistently absorb nitrate after the 1 st 2h of adaptation. The amount of nitrate absorption was higher in polyploid than in diploid. The absorption of different cultivars with the same ploidy were in the following order. E type (high yielding), NE type (standard with high yielding) , NZ type(standard with high sugar) , Z type(high sugar). There were different nitrate absorption kinetic parameters, Km, app and Im, in different type of sugar beet cultivars.The order of exudate volume, nitrate amount in exudate and rate of nitrate transport to shoot among cultivars were the same as their Im values. NRA in vivo in cotyledons after 4h induction was significantly and positively correlated with the amount of nitrate absorption during 4h and rate of nitrate transport to shoot, respectively, no matter the reaction solution contained nitrate or not.
出处
《作物学报》
CAS
CSCD
北大核心
1996年第6期681-687,共7页
Acta Agronomica Sinica
基金
国家自然科学基金
霍英东青年教师基金资助项目
关键词
甜菜
硝态氮吸收
硝态氮上运
硝酸还原酶活性
Cotyledon stage of sugar beet
Nitrate uptake
Nitrate upward transport
Exudation
Nitrate reductase activity
