摘要
以高硝酸盐积累品种四月慢和低硝酸盐积累品种华冠青梗菜为材料,采用溶液培养方法,测定了0.2和2mmol/L NO3-处理下的硝酸盐积累量和硝酸还原酶活性,并应用Real-Time PCR技术检测了NO3-吸收基因NRT1和NRT2的表达量。结果表明：（1）除0.2 mmol/L NO3^-处理时的叶片硝酸盐含量没有显著差异外,四月慢植株各部位的硝酸盐含量都显著高于华冠青梗菜,高浓度培养使品种间硝酸盐积累量差异增加,四月慢对NO3^-水平增加的响应能力强于华冠青梗菜。（2）吸收液NO3^-浓度12-0 mmol/L范围内,四月慢对NO3-离子吸收速率显著高于华冠青梗菜,且在高浓度下表现更显著。（3）在2 mmol/L NO3-处理下,NRT2在根、叶片、叶柄中的表达量都是四月慢显著高于华冠青梗菜,NRT1的表达量只有在根中四月慢显著高于华冠青梗菜,而在叶片和叶柄中都没有显著差异;在0.2 mmol/L NO3^-处理下,NRT1和NRT2表达情况相同,都是在叶片和叶柄中四月慢显著高于华冠青梗菜,而在根中表达量品种间没有显著差异。（4）NRT1和NRT2的表达在一定程度上可以解释硝酸盐积累量的差异,可能还有其他的基因对硝酸盐积累的基因型差异起重要作用,尤其是0.2 mmol/L NO3^-处理时。（5）四月慢的硝酸还原酶活性显著高于华冠青梗菜,即四月慢对硝酸根同化利用的能力强于华冠青梗菜。
Two Chinese cabbage [Brassica campestris ssp.chinensis（L.） Makino] cultivars（SYM and HGQGC） different significant in nitrate accumulation were used in our research to investigate the mechanism involved in nitrate absorption.With 0.2 and 2 mmol/L NO3^- treatments,the nitrate concentration,nitrate uptake rate,nitrate reductase activity（NRA） and the expression level of NRT1 and NRT2 were measured.The data suggested that firstly,the nitrate concentration in SYM was higher than that in HGQGC especially under higher nitrate treatment except for leaves with 02mmol/L NO3^- supply.The increment of nitrate concentration in SYM was also higher than that in HGQGC following the enhancement of nitrate in growing medium.Secondly,the nitrate uptake rate of SYM was higher than that of HGQGC with 020mmol/L NO3^- in growing medium,also especially with higher NO3^- solution.Thirdly,with 2mmol/L NO-3 treatment,the expression patterns of NRT2 was consistent with the nitrate concentration in root,leaves and stem,that means the expression levels of NRT2 in SYM was higher than that of HGQGC,while the same instance only occur in root for NRT1 expression.under 0.2 mmol/L NO3^- treatment,only in stem the nitrate concentration,expression level of NRT1 and NRT2 were all higher in SYM than those in HGQGC.Fourthly,the different expression patterns of NRT1 and NRT2 maybe partly responsible for the different nitrate accumulation between cultivars and there must be some unknown genes also participated in nitrate accumulation especially in 0.2 mmol/L NO3^- treatment.Lastly,the NRA of SYM was also higher than HGQGC that means the higher nitrate use efficiency in SYM.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2010年第3期681-687,共7页
Journal of Plant Nutrition and Fertilizers
基金
浙江省自然科学基金(Y307531)
浙江省农业科学院创新提升项目资助
关键词
小白菜
NRT
硝酸盐
基因型
Chinese cabbage
NRT
nitrate
genotype difference
