Evaluations Of Production Performance And Adaptability Of 44 Alfalfa Cultivars With Different Fall Dormancy Grades

Alfalfa(Medicago Sativa L.)is known as the "King of Forage".It has the advantages of high yield,high crude protein content,and good palatability.It plays an irreplaceable role in the development of global animal husbandry.The research results on the production performance and ecological habits of the same alfalfa cultivars in different regions are quite different.Blind introduction often leads to a series of problems such as inability to overwinter,low yield,poor quality,and low resistance to diseases and insects,causing many problems to farmers and related enterprises.Therefore,to determine the suitable cultivars in a certain area,it is necessary to do strict variety adaptability studies,and to fully consider the differences caused by the conditions of water,fertilizers,climate and managements in the planting lands.In this experiment,44 alfalfa cultivars at home and abroad were used as the research object-with a random block design.The overwintering rate was investigated.Plant height,stem diameter,and internode number,internode length,leaf number,leaf length,leaf width,stem/leaf ratio,fresh/dry ratio,as well as crude protein,total phosphorus and other related nutritional indicators were determined during the branching,budding,and Early flowering stage stages.The production performance of 44 alfalfa cultivars were assessed via a comprehensive evaluation of correlation analysis.The most suitable cultivars for planting in Yangling area were selected.The main results of this study are as follows:1.There was a very significant difference in overwintering rate among alfalfa cultivars(P<0.01).There were 30 cultivars with overwintering rate higher than 90%,among which Bara 416 WET and Bara 420 YQ ranked first and second,respectively.Fast-growing cultivars could increase their yield during the initial flowering stage.Claudia has the fastest average growth rate,which is 1.36 cm/d.2.Plant height can reflect the growth status of forage grass.Bara 416 WET has the highest plant height at 106.93 cm at the first flowering stage.The number of leaves is one of the key elements that constitute the yield.At the initial flowering stage,there are more leaves in the forerunner(175.30),Aohan(180.10),Nongjing No.8(177.00),Aihe No.1(192.70)and WL168HQ(176.30).Hay weight is the most intuitive reflection of yield.Alfalfa varieties with hay weight over 40 g at the initial flowering stage include Pioneer,Aihe No.1,Nongjing No.8,Bara 416 WET,Bara 218 TR,Bara 420 YQ,Blue moon,WL198 HQ and WL298 HQ.3.The level of crude protein content directly affects the quality of forage.The crude protein content in alfalfa leaves is much higher than that in stems.The variety with the highest crude protein content in the stem was WL313 HQ,which was 14.42%,which was significantly higher than the other 43 varieties(P<0.05);the variety with the highest crude protein content in the leaves was Nongjing No.8,with a crude protein content as high as 26.33%.4.Correlation analysis between alfalfa productivity status and various traits related to nutrient composition shows that there was a very significant positive correlation between dry weight and overwintering rate,plant height,internode number,leaf number,leaf length,fresh weight and other factors(P<0.01),and there was a very significant negative correlation between dry weight and fresh:dry ratio(P<0.01).There was a very significant positive correlation between crude protein and total phosphorus contents.(P<0.01).Clustering,gray correlation degree and fuzzy mathematics membership function method indicate that the cultivars with better comprehensive evaluation were Nongjing No.8,Bara416 WET,Pioneer,Aihe No.1,WL168 HQ and Aohan,which are more suitable for Yangling Area planted.