Effects Of Fertilizer And Row Spacing On The Seed Yield And Seed Quality Of Medicago Sativa L. And Onobrychis Viciaefolia Scop. Cv. Mengnong

From 2008 to 2009, the experiment used alfalfa and Onobrychis viciaefolia Scop. cv. Mengnong as sample, to study the effects of row spacing, phosphorus and potassium on the seed yield and quality. The experiment were conducted in the field, and laboratory experiments on physiology and biochemistry were researched. The results indicated that:1. The effects of row spacing on the seed yield of alfalfa and Onobrychis viciaefolia Scop. cv. Mengnong were evidently (P<0.5). The alfalfa seed yield of 70 cm row spacing was the highest, significantly increased by 20.8% and 24.4% compared with 50 cm and 90 cm row spacing. The highest seed yield of 1216 kg/hm2 was obtained with 50 cm row spacing of Onobrychis viciaefolia Scop. cv. Mengnong, evidently increased by 57.25% compared with the 90cm row spacing. The seed quality of alfalfa and Onobrychis viciaefolia Scop. cv. Mengnong response to row spacing was not significant (P>0.5).2. The P rate of 50 kg/hm2 resulted in a maximum seed yield of alfalfa, in the first patterns, markedly increased by 28.3% compared with CK in the first patterns (P<0.5). And the seed,s relative electric conductivity, seed's soluble sugar content and seed,s MDA content with P rate of 50 kg/hm2, were the lowest in the first patterns. The highest seed yield was obtained with the P rate of 100 kg/hm2, in the second patterns, significantly increased by 33.1% compared with CK (P<0.5). The seed's soluble sugar content and MDA content of the P rate of 100 kg/hm2, were the lowest in the second patterns.The maximum seed yield was obtained with the P rate of 100 kg/hm2, in the third patterns, significantly increased by 36.7% compared with CK (P<0.5). The seed,s MDA content of the P rate of 100 kg/hm2, evidently decreased by 23% compared with CK in the third patterns (P<0.5).3. The seed yield and seed,s MDA content of alfalfa with potassium treatment, were significantly decreased in the three patterns (P<0.5). Economically considered, there was little or no potassium fertilization in the seed producing field of alfalfa.4. In the three patterns, the maximum seed yields of Onobrychis viciaefolia Scop. cv. Mengnong were obtained with the P rate of 100kg/hm2, and the seed,s relative electric conductivity of that were the lowest. The s seed,s MDA content with phosphorus treatment were significantly decreased in the three patterns (P<0.5).In terms of seed production, phosphorus application could increase the seed yield of Onobrychis viciaefolia Scop. cv. Mengnong.5. The effect of K application on the seed yield of Onobrychis viciaefolia Scop. cv. Mengnong was not significant (P>0.5), but the seed,s relative electric conductivity, soluble sugar content and MDA content were significantly decreased in the three patterns (P<0.5). Therefore, potassium application could not increase the seed yield of Onobrychis viciaefolia Scop. cv. Mengnong, but in a way, improved the seed quality.