精播高产小麦吸氮和土壤供氮特点及施肥效益的研究

CHARACTERISTICS OF NITROGEN UPTAKE BY WINTER WHEAT PLANT,SOIL NITROGEN SUPPLY AND BENIFITS OF FERTILIZATION UNDERPRECISION DRILLING HIGH YIELDING CONDITIONS

每公顷产７６３５ｋｇ小麦籽粒，全生育期植株吸氮量为２４７．５ｋｇ／ｈｍ２，其中冬前吸氮量占总吸氮量的１８．８％，越冬期占１０．８％，返青至拔节期占２１．７％，拔节至孕穗期占２９．５％，孕穗至开花期占９．５％，开花至成熟期占９．７％。各生育期的吸氮强度（每日每公顷吸氮量）以拔节至孕穗期最高，其次为返青至拔节期，但是氮素的相对积累速率则以分蘖至越冬始期最高，其次为拔节至孕穗期。文中还讨论了施氮对叶片衰老、籽粒产量和蛋白质产量的影响、氮肥的生产效率及适宜的施氮指标。

The experiment were conducted at Feicheng county, Shandong province and Experiment farm of Shandong Agricultural University during 1989-1991. The total N uptake fora grain yield of 7635kg / hm2 was about 247.5kg / hm2,of which 5.6% was absorbed atemergence of seedling to tillering, 13.3% at tilling to the beginning of overwinter, 10.8% atoverwinter, 21 .7% at regreening to jointing, 29.5% at jointing to booting, 9.5% at bootingto anthesis, and 9.7% at anthesis to maturation. The nitrogen uptake intensity (Ng / hm2 / day) was the highest at jointing to booting stage. There were two peaks of relativeaccumulative rate of nitrogen (mg/g/day),one was at tillering to the beginning ofoverwinter, and the other was at jointing to booting stage.