Effects Of Different Densities And Mixed Community Structures On Seed Production Of Vicia Sativa

In order to explore the influence mechanism of mixed planting patterns on the seed production of Vicia sativa.Different densities and mixed community structures were used in this study as control means to analyze seed yield,quality and related biological and functional traits of Vicia sativa through plot experiments.At the same time,the mixed community structures of grassland,the content of soil nutrients,and the internal relationship between competition condition and soil nutrient content with seed production of Vicia sativa were analyzed.The main results were as follow:（1）Different densities and mixed community structures had great influence on Sh/P and Po/P value of Vicia sativa and little influence on the biological traits such as LP,S/Po and GR value of Vicia sativa.The seed yield（SY）increased with the increase of the seeding rates of Vicia sativa,and the seed yield of the mixed sowing was less than that of the single seeding treatment.The effect of mixed sowing（mixed cropping/intercropping）on SY value of Vicia sativa and the quality of the seed was less.When the single sowing amount was 150 kg·hm^-2,the single branch number（Sh/P）and Po/P value of Vicia sativa were higher,and the SY value of Vicia sativa was also larger.In the mixed sowing population,the SY value of Vicia sativa in the mixed sowing combination of Vicia sativa and Avena sativa 80%:20%(Avena sativa 96 kg·hm^-2+Avena sativa36 kg·hm^-2)was larger,andthe GP value of Vicia sativa was higher than that in unicast.（2）The sum of RYT value of all mixed sowing communities was greater than 1,and LER value of seed yield was also greater than 1.The mixed sowing of Vicia sativa and Avena sativa50%:50%(Vicia sativa 60 kg·hm^-2+Avena sativa 90 kg·hm^-2)and 75%:25%(Vicia sativa 90kg·hm^-2+Avena sativa 45 kg·hm^-2)had higher LER value and RYT value.The CR_Jvalue was higher when the mixed sowing of Vicia sativa and Avena sativa 80%:20%(Vicia sativa 96kg·hm^-2+Avena sativa 36 kg·hm^-2),and CR_Yvalue was higher when the mixed sowing of Vicia sativa and Avena sativa 50%:50%(Vicia sativa 60 kg·hm^-2+Avena sativa 90 kg·hm^-2).When the RYT value was higher,the SY value was also higher,but the seed yield of Vicia sativa decreased while the RYT value was too high or low.The CR_Jvalue was in the same line with the seed yield of Avena sativa,and the LER value and CR_Yvalue were both with the arrow.The yield of pea seed was in double Peak curve.When the LER value was in the middle or the wheat CR_Yvalue was low,the seed yield of Avena sativa was higher.（3）The content of available N and P in 0～10 cm soil and the content of available N in 10～20 cm soil were higher in unicast than that in the mixed sowing,and with the increase of the mixed sowing ratio of Vicia sativa,the content of the available N in the 0～10 cm soil was a reduction trend,and the total nutrient content in the soil of the Vicia sativa and Avena sativa mixed sowing community was higher than that in the single sowing.The content of organic matter in 0～20 cm soil was the highest in the mixed cropping of Vicia sativa and Avena sativa 80%:20%(Vicia sativa96 kg·hm^-2+oat 36 kg·hm^-2).The content of total N in 0～10 cm soil was the highest in the mixed cropping of Vicia sativa and Avena sativa 75%:25%(Vicia sativa 90 kg·hm^-2+Avena sativa 45kg·hm^-2).The content of total N in 10～20 cm soil was the highest in the intercropping of Vicia sativa and Avena sativa 75%:25%(Vicia sativa 90 kg·hm^-2+Avena sativa 45 kg·hm^-2).From the mixed patterns（mixed cropping/intercropping）,the contents of soil organic matter and total nutrient were higher in intercropping,and the contents of soil available nutrients were higher in mixed cropping.The total N,available N,and available P content in 0～10cm soil had a greater impact on seed yield of Vicia sativa.Total N in 0～10 cm soil and soil available P content in10～20cm soil had a greater impact on seed quality of Vicia sativa.Therefore,in order to produce more seed yield and higher seed quality of Vicia sativa,the competition ratio of Vicia sativa in the mixed communities should be enhanced by increasing the mixed ratios of Vicia sativa and using the intercropping pattern.In conclusion,the seed fields of Vicia sativa in the cool climate pastoral areas need high sowing quantities,intercropping pattern and higher mixed ratios（The proportion of Vicia sativa mixed sowing is greater than or equal to80%）.