The Effects Of Nitrogen Fertilization And Harvest Time On Seed Yield And Quality Of Kengyilia Rigidula

This study was performed for two years in 2016–2017 at Hongyuan,Sichuan mainly to research the effects of N fertilizer and harvest time on seed yield and quality,so as to determine the optimal N fertilizer application and harvest time of Kengyilia rigidula cv.Aba.This study lays the foundation for the theoretical research and practical production of forage grasses.N fertilizer could increase the yield components and seed yield of K.rigidula.With the increase of N fertilizer application,the seed yield gradually increased and peaked at N₆treatment,then seed yield small decreased after N₆.The number of generative tillers/m²was most influenced and then was 1,000-seed-weight under N fertilizer treatment,the number of generative spikes per spikelet and spikes per spikelet were slightly affected while the number of spikes per generative tillers was not significantly affected by N fertilizer.The quality of seeds harvested early could be slightly promoted with suited N fertilizer,such as germination rate,accelerated aging germination rate,TTC content and acid phospholipase activity,while the mature seeds were not affected by N fertilizer.The results showed that the optimal N fertilizer application was 180 kg/hm²in seed production of K.rigidula at Northwest Sichuan Plateau.The water content of seeds firstly slowly decreased,then rapidly decreased and eventually plateaued with the gradual maturation of K.rigidula seeds.The water content of seeds was dropped to minimum at D₆,and the fresh weight and dry weight of seeds and seed yield were highest.The quality of seeds gradually increased,and the vigor of seeds was highest at D₆.At this time,the germination rate,accelerated aging germination rate,TTC content and acid phosphatase activity of seeds were the highest,but they decreased after N₆.The results showed that the latest harvest time of seeds was at D₆ in seed production of K.rigidula at Northwest Sichuan Plateau.The water content of seeds was under 40%at D₅,so the optimal harvest time of seeds was the period D₆.