中文摘要：

以豫麦49-198和平安8号为供试材料，在河南温县赵堡大田条件下，设置N0、N120、N180、N240、N360 kg·hm-2 5个施N处理，研究不同施氮量对小麦茎蘖消长、产量和小麦花后干物质的影响。结果表明，2品种均从分蘖期开始群体数量不断增加，到拔节期达到最大，之后开始下降。不同处理问豫麦49—198在越冬期、返青期、拔节期、抽穗期群体数量差异均不显著，成熟期不同处理群体数量差异显著；而平安8号在越冬期、返青期、拔节期不同处理群体数量差异均不显著，拔节期以后不同处理间群体数量差异显著。随氮肥用量增加，不同处理干物质积累量和籽粒产量提高，干物质积累量豫麦49—198表现为N360〉N240〉N180〉N120〉N0，而平安8号表现为N240〉N360〉N180〉N120〉N0。豫麦49—198和平安8号花后干物质积累量和花后积累贡献率分别在N180、N240达到最大，分别为7448.28kg·hm-2、83．99％和8177．55kg·hm-2、94．49％，花前积累贡献率则为17．68％、5．51％。籽粒产量豫麦49—198在N180和N240处理最高，分别为8544．00、8753．33kg·hm-2；平安8号以N240产量最高，籽粒产量达到8232．00kg·hm-2。在本试验土壤肥力条件下，建议施氮量为180～240kg·hm-2。

英文摘要：

Taking wheat cultivars Yumai 49-198 and Ping＇an 8 as the test materials, field experiments were conducted at Wenxian site of Henan Province to study the effects of nitrogen fertilization on their population dynamics, yield and post-anthesis dry matter accumulation. Five nitrogen application rates ,N0 ,N120,N180,N240, N360 were installed. The results show that the populations of the two test cultivars were all increased after tillering stage, reached the highest at jointing stage, and decreased afterwards. As for Yumai 49-198, its population had no significant differences at wintering, turning green stage, jointing stage and heading stage among the five nitrogen application rates, but differed significantly at the maturity with the nitrogen application rates. For Ping＇an 8, its population had no significant differences among the nitrogen application rates at the wintering, turning green stage and jointing stage, but differed significantly after jointing stage with the nitrogen application rates. Wheat yield and dry matter accumulation of each treatment increased with the increase of nitrogen fertiliza tion rate, but the grain yield decreased with excessive nitrogen fertilization. The dry matter accumulation performance of Yumai 49-198 in different treatments was N360〉N240〉N180〉N120〉N0, and the performance of Ping＇an 8 was N240〉N360〉N180〉 N120〉N0. The post-anthesis dry matter accumulation and contribution rate of Yumai 49-198 and Ping＇an 8 reached the maximum at N180 and N240, being 7 448.28 kg·hm-2, 83.99% and 8 177.55 kg · hm-2,94.49%,respectively; Contribution rate of accumulation before flowering was 17. 680% and 5.51%. Yumai 49-198 had the highest yield at N180 and N240, being 8 544.00 kg· hm-2 and 8 753.33 kg ·hm-2 , Ping＇an 8 had the highest yield at N240, being 8 232. 00 kg·hm-2. As a summary, the recommended nitrogen application is 180--240 kg· hm-2 under the current soil fertility condition.