Study On The Agronomic Traits Of A New High-yield Alfalfa Strain In Medicago Varia Martin.cv.Caoyuan No.3

The purpose of this experiment was to study the effect of improving agronomic characters of Medicago varia Martin.cv.Caoyuan No.3.In this experiment,Medicago varia Martin.cv.Caoyuan No.3.was used as control and the new strain with high yield was used as the object.Field experiments were carried out in inner mongolia agricultural university from 2019 to 2020.By observing the phenophase,the morphology,growth characteristics,productivity and photosynthetic parameters of the cluster were analyzed and compared.The results showed that:（1）Compared with the control,the new strain entered the reviving period 7days earlier and the branching period 8 days earlier.（2）The agronomic characters of the new strain were better than that the control.Compared with the control,plant height,stem diameter,leaf ratio,dry to fresh ratio,growth intensity,tiller number,the first lateral branch number,leaf dry weight,fresh weight and dry weight increased significantly.（3）The new strain showed good reproducibility and orthotropism.Compared with the control,the height,speed,number of regeneration branches and total weight of regeneration plants increased significantly,the height of annual growth was 51.2cm,and the angle between the main branch and the ground was 29°.（4）The new strain was more productive as the control.The yield increased by19.22%,the yield of each cutting stubble times accounted for 51.35%,29.73%and18.64%of the annual yield respectively.（5）The new strain has stronger photosynthetic capacity.The net photosynthetic rate and stomatal conductance were higher and the intercellular CO₂concentration was lower than the control.