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试验以我国不同年代的35个玉米品种为材料,在施氮肥和不施氮肥两个水平下对产量、穗长、穗粗、穗粒数、秃尖长、轴粗、百粒重共7个农艺性状进行考查比较。结果表明,除轴粗以外,其余几个农艺性状不同年代间差异均达到显著或极显著水平,随年代变化玉米品种产量显著提高,氮胁迫压力下不同年代玉米品种产量均下降。正常施氮条件下,各年代玉米品种的穗长、穗粗、穗粒数呈上升趋势,低氮胁迫降低了穗长、穗粗、穗粒数及百粒重,而对轴粗无明显影响。研究还表明,1950年以来我国玉米品种的耐低氮能力没有明显提高。育种工作要在自交系选育中重视低氮条件,为进一步培育耐低氮杂交种奠定基础。
In this experiment, 35 maize varieties from different ages in China were used as materials to study the effects of nitrogen and nitrogen fertilization on the yield, ear length, ear diameter, spikelet number, bald length, Agronomic traits comparison test. The results showed that in addition to the shaft thick, the remaining several agronomic traits in different years have reached significant or extremely significant level, with the age of maize varieties significantly increased yield, nitrogen stress in different years under different maize varieties decreased. Under normal nitrogen application, the spike length, ear diameter and spike number of maize varieties increased in all ages, and the spike length, ear diameter, grain number per spike and 100-grain weight decreased under low nitrogen stress, but had no significant effect on the stem diameter . The research also shows that the low nitrogen tolerance of China’s maize varieties has not been significantly improved since 1950. Breeding efforts should focus on low nitrogen conditions in inbred line selection and lay the foundation for further breeding low-nitrogen tolerant hybrids.