成熟期不同基因型谷子对低氮胁迫的响应

Response of Different Genotypes of Millet to Low Nitrogen Stress at Maturity

为研究耐低氮谷子生理机制,挖掘氮高效利用种质资源,本研究采用盆栽试验,以6个不同基因型谷子品种为材料,设置正常施氮(120 mg/kg, NN)和不施氮(N0)两个处理,分析不同处理对6个谷子品种叶片光合性能、各营养器官氮含量、氮素分配比例和籽粒主要品质指标的影响。结果表明,不同谷子品种的生物量、千粒重、籽粒氮含量、植株全氮含量及不同器官的氮素积累量、氮素分配比例有显著差异(P<0.05)。N0处理下,同其他基因型谷子品种相比,济谷17千粒重增加11.1%~21.6%,籽粒中氮素分配比例及粗纤维、赖氨酸含量分别增加3.5%~9.5%、9.7%~18.2%、0.3%~45.5%;NN处理与N0处理相比,各基因型谷子品种植株氮含量及籽粒氮含量分别增加8.8%~20.7%、2.3%~22.4%。聚类分析结果表明,正常施氮和不施氮条件下,济谷17和豫谷18均表现较优,长农35则对低氮环境比较敏感。本研究结果可为耐低氮谷子品种选育和种植提供理论依据。

In order to study the physiological mechanisms of low nitrogen tolerance in foxtail millet and explore germplasm resources with efficient utilization of nitrogen,pot experiment was taken with six genotypes of foxtail millet varieties were used as materials.Two treatments of normal nitrogen(120 mg/kg,NN)and no nitrogen(N0)were set to study their effects on leaf photosynthetic performance,nitrogen contents in various nutrient organs,nitrogen allocation ratio,and main nutritional indicators of grains.The results showed that there were significant differences(P<0.05)in biomass,thousand grain weight,grain nitrogen content,plant total nitrogen content,and nitrogen accumulation and allocation ratio in different organs among millet varieties.Compared with other genotypes of foxtail millet in treatment N0,the 1000-grain weight,and nitrogen alloca-tion ratio,crude fibre and lysine contents in grains of Jigu 17 increased by 11.1~21.6%,3.5%~9.5%,9.7%~18.2%and 0.3%~45.5%,respectively.Compared with treatment N0,the plant total nitrogen and grain nitro-gen contents in different genotypes of foxtail millet increased by 8.8%~20.7%and 2.3%~22.4%respectively in NN treatment.Clustering analysis showed that the varieties of Jigu 17 and Yugu 18 performed better under both normal and no nitrogen treatments,while Changnong 35 was more sensitive to low nitrogen environment.These results could provide theoretical references for breeding and planting of millet varieties with tolerance to low nitrogen.