Effects Of Fertilizing And Shading On Sexual Reproduction In Leymus Chinensis

Leymus chinensis is the dominant species of eastern Eurasia steppe. However, It's has small numbers of seed and weak on the sexual reproduction in natural conditions. The seed yield refrain the artificial utilizing for it severely. Fertilization and lighting is the efficient method for enhancing the seed yield. The study of fertilization and shading in Leymus chinensis are poorly demonstrated at present. So we investigated the effects of Nitrogen, Phosphorus, Kalium and shorten the lighting time in reproduction stage on heading percent, setting percentage and seed yield by orthodox design experiments and shading method in different reproduction stage.The result shows that Nitrogen, Phosphorus Kalium had no significance for heading percent and heading number but for enhancing the setting percentage and seed number through different fertilization kinds and combination, so the seed yield are significantly increased. The effects of former stage fertilize Nitrogen and Kalium on seed and seed yield is greater. We concluded that N3P1K3t1 is the best combination theoretically through using Range analysis.The result shows that N, K and time had a significant effects on the leaf area and the reproduction allocation to the plump grain (p<0.01). P didn't reach the significant level, but it was close to it. Fertilization at former stage has greater effects on Leaf area and Reproduction allocation. Correlation coefficient of the leaf area and setting percentage, the plump grain, and the reproduction allocation to the plump grain is 0.875**, 0.886**, 0.827** respectively. It indicated Leaf area have an effects on setting percentage, seed yield et al.In shading experiment, the results show that the heading percentage, setting percentage, seed yield, seed number and the weight of 1000 grains were decreased extremely significant. and made the heading number significantly decreased but no significance on vegetation number through Shading during May 20 and June 20 (p<0.01). It is no significance on subjects of above though shading treatment during June 20 and July 20. This indicated Leymus chinensis are very sensitive on the lighting time of former stages during pregnant spikes stage. A confined factor of the seed production is lack of lighting at former stage. Lighting time may be determined factor for the heading number and seed yield.