Studies On The Production Performance,Nutritional Value And Stress Resistance Of Red Clover Lines

Trifolium pratense L.is a short-term perennial plant and occupies an important position in pasture.It has high forage yield and good quality,therefor,it plays important significance for the sustainable development of animal husbandry.In order to understand the forage productivity and stress resistance of new red clover line(R)and lay the foundation for variety regeistration,new red clover line(R)was used as the experimental material,Minshan red clover(CK1)and Ganhong No.1 red clover(CK2)were used as controls in this paper,forage productivity,nutrition,drought and cold resistance were studied.Main results are as follows:1.Results of the forage productivity and nutrition showed that,among red clover materials,R had the highest number of branchs(15.78 million/ha),hay yield(9.27 t/ha)and fresh dry ratio(5.02),EE content(2.12%)was slightly lower than that of CK1(2.37%),NDF content was the lowest(39.94%),and ADF content(34.73%)was located between 2 controls.CK2 had the highest plant height(80.42 cm),its number of branches(13.61 million/ha),hay yield(8.09 t/ha)and fresh dry ratio(4.75)were lower than that of R.The highest CP content(20.68 %)was found in CK1.Branch number,hay yield,fresh dry ratio and EE content in 2017 were higher than those in 2016,while plant height,CP,ADF and NDF contents were lower than those in 2016.From the interaction of year and material,the branch number of R in 2017 was the highest(17.49 million/ha),plant height of CK2 in 2016 was the highest(83.23 cm),the CP content of R in 2017 was the highest(27.38%),the EE content of CK2 in 2016 was the highest(2.81%),NDF(35.24%)and ADF(32.45%)in 2017 CK2 was the lowest.Comprehensive evaluation based on the gray relational degree model showed that,forage production and nutrition of R is better than that of CK1 and CK2.2.Along with the aggravation of drought stress,content of leaf water(LWC),chlorophyll(CHL),malondialdehyde(MDA),soluble sugar(SS)content;peroxidase(POD),superoxide dismutase(SOD)and catalase(CAT)activity varied.CHL content and LWC decreased,contents of MDA and SS increased,and activities of POD,SOD and CAT increased first and then decreased.Comprehensive evaluation based on the membership function method showed that R was the most drought tolerant,followed by CK2 and CK1.3.Along with the aggravation of cold stress,contents of LWC and CHL decreased,MDA and SS increased,and activitivies of POD,SOD and CAT increased first and then decreased.Comprehensive evaluation showed that R was the most cold resistance,followed by CK1 and CK2.4.New red clover line(R)has high yield and good quality,and its drought resistance and cold resistance are better than those of CK1 and CK2.