Effect of Nitrogen Fertilizer Application on Elymus Nutans Seed Quality and Yield in Qinghai-Tibet Plateau

Field experiments were conducted in Sanjiaocheng Stud Farm in two years(2001-2002),to test the effects of nitrogen fertilizer application on Elymus nutans seed yield and seed quality.Results show that the yield reached the highest rate of 1856 kg/hm~2 with 120 kg/hm~2 N application(Autumn 60+Spring 60).The fertilizer significantly raises the seed yield components,including fertile tillers/m~2,florets per spikelet,fertile florets per spikelet,and thousand-seed weight,though it does not influence spikelets per fertile tiller.The fertilizer also raises the early-mature seed germination rate,seedling length and weight,as well as the acid phosphoesterase activity.