Comparative Analysis Of Alfalfa Yield Components In Different Soil Conditions

Alfalfa(Medicago Sativa L.)is a high-quality and important legume forage grass in the forage industry development,known as "king of forage" reputation due to the traits of high yield,abiotic stress resistance,nutrient-richness,good palatability etc.In recent years,the state vigorously promotes the development of grass and animal husbandry,the cereals planting convert to grasses planting promotion need be expanded in the northeastern cold areas by government,to improve silage corn and alfalfa and other forage acreage.The promotion of alfalfa cultivation can not only promote the industrial structure adjustment of Jilin Province to meet the demand of high quality protein forage,but also help to make comprehensive use of western land resources and thus improve the utilization efficiency of land resources.In this paper,alfalfa was used to study the growth of one alfalfa variety with different planting densities,and the same planting densityon different genotypes alfalfa on two soil types widely distributed in western Jilin Province.The biomass yield,plant height,the number of branches and other yield components were evaluated synthetically,and the correlation analysis and path analysis were carried out between the yield and yield components,aims to lay the foundation for the collection and evaluation of alfalfa germplasm resources and the breeding and production control of high yield alfalfa varieties.The main conclusions are as follows:1.When the planting density was different,the yield of alfalfa increased with the increase of planting density in the two soil conditions,and the yield was only correlated positively with plant height.Therefore,if only aim to harvest for the first crop year,the results indicated that high-density planting with the 40 plant per m2 would induce a highest yield.During the second crop year,the yield of alfalfa increased with the increasing of density,and then decreased after reached the peak.In the sandy soil experiment,the results showed that yield were positive correlated with plant height and internode number,the stepwise analysis also proof that internode number had a positive effect on the yield,followed by the plant height,while fresh to dry matter ratio was negative affect to the yield,therefore,well adjust the traits mentioned above couldachieve high yield performance on the sandy soil;by contrary,the number of internodes had a positive effect on yield and single branch weight had negative effect on it in thesaline-alkali soil,in this experiment well balanced these two traits with the density of 30 plants per m2 could achieve the highest yield.2.When different genotypes planted in sandy soil,in the first crop year,Dongmu No.3,Kangsai and Qishi No.2 obtainedthe largest yield.Stepwise analysising results showed that the highest contribution to the yield was plant height,followed by stem thick,but fresh to dry matter ratio and the number of internodes were negative affect to yield,therefore,select the genotype with the reasonable four yield components mentioned above could achieve high yield,the genotype identified in this experiment were Dongmu No.1,Dongmu No.3 and Zhaodong.When different genotypes planted insaline-alkalisoil,the genotype Dongmu No.1,Saikang and Xinmu No.1 exhibited highest yield,and plant height,single branch weight and fresh to dry matter ratio were significantly correlated with the yield.The stepwise analyzing results showed that the largest contribution to yield was plant height,followed with fresh to dry matter ratio,while single weight and stem to leaf ratio had a negative effect to yield;for the second crop year,Longmu 801,Qishi T and Kangsai obtained the highest yield,the significant correlation coefficients were detected for plant Hight,internode number and fresh to dry matter ratio with the yield,whereas plant height had a largest contribution to the yield while fresh to dry ratio was still negative affect to yield,therefore,select the genotype with higher plant height and lower fresh to dry matter ratio could achieve high yield in the saline-alkalisoil.Planting the following year,Long Mu 801,Knight T and Kangsai the highest yield,plant height,internode and fresh dry ratio and yield and the freshness ratio is still the negative effect,it is desirable to choose the relatively high plant height and fresh and relatively small varieties in the saline soil cultivation,can be obtained from the high yield of alfalfa...