谷子氮高效基因型筛选及相关特性分析

Screening of Foxtail Millet Genotype with High Nitrogen Use Efficiency and Analysis of Related Characters

在低氮(0.5 mmol/L)和高氮(5.0 mmol/L)2个氮素水平下,研究不同氮效率谷子基因型的光合特性、农艺性状、氮含量、吸氮量、氮利用率、氮代谢相关酶活性及其相关性,以期为氮高效谷子新品种的选育提供基础材料。结果表明,低氮和高氮水平下,不同谷子基因型光合特性、主要农艺性状、氮含量及吸收利用指标变异系数分别为16.2%~34.4%和15.2%~22.5%、15.2%~55.4%和17.9%~49.3%、13.7%~28.4%和15.8%~23.7%。2个氮素水平下,谷子产量与光合速率、穗长、单穗质量、地上部生物量、吸氮量和氮利用率均呈显著或极显著正相关,与茎秆和根氮含量均呈显著负相关。根据2个氮素水平下的谷子产量差异将其分为双高效型、高氮高效型、低氮高效型和双低效型4种类型。豫谷17、豫谷23、冀谷33等在低氮和高氮水平下产量、吸氮量、氮利用率、氮代谢相关酶活性均表现突出,受氮肥影响较小,为典型双高效型基因型,适宜贫瘠地区种植;冀谷41、七叶黄、郑11-2等在低氮和高氮水平下均表现出氮低效利用特性,受氮肥影响较大,为典型双低效型基因型。

The photosynthetic characteristics,agronomic traits,nitrogen(N) content,N uptake quantity,N use efficiency,activity of enzyme related with N metabolism and correlation among the characters of different foxtail millet genotypes with different N use efficiency were studied under low (0.5 mmol/L) and high(5.0 mmol/L)levels of N,so as to provide basis materials for breeding of foxtail millet variety with high N use efficiency.The results showed that the coefficients of variation of photosynthetic characteristics,agronomic traits,N content and N use efficiency were 16.2%-34.4%,15.2%-55.4% and 13.7%-28.4% under low level of N,and 15.2%-22.5%,17.9%-49.3% and 15.8%- 23.7% under high level of N,respectively.Grain yield was significantly positively associated with photosynthetic rate,spike length,single spike weight,aboveground biomass,N uptake quantity and N use efficiency,and significantly negatively associated with the N contents of stalks and roots under two N levels. The foxtail millet varieties(lines) were divided into four types based on grain yield under two N levels,which were type with high N use efficiency under low and high levels of N,type with high N use efficiency under low level of N and low N use efficiency under high level of N,type with low N use efficiency under low level of N and high N use efficiency under high level of N,type with low N use efficiency under low and high levels of N. Yugu 17,Yugu 23 and Jigu 33 were the typical genotypes with high N use efficiency under low and high levels of N,which had higher grain yield,N uptake quantity,N use efficiency and activities of enzymes related with N metabolism under low and high levels of N,and were slightly influenced by N fertilizer,and suitably planted in poor soil;however,Jigu 41,Qiyehuang and Zheng 11-2 were typical genotypes with low N use efficiency under low and high levels of N,which showed characteristics with low N use efficiency under low and high levels of N,and were greatly influenced by N fertilizer.