Analysis On The Preliminary Evluation Of 8 Resources Watermelon Germplasm

In order to evaluate the excellent germplasm resources of watermelon,and to screen the excellent traits in line with the modern breeding and target of watermelon,this study investigated 8 kinds of watermelon germplasm resources(feed watermelon,medicinal watermelon and wild watermelon)as materials.The main agronomic characters were investigated,the diversity of agronomic characters was analyzed,and the contents of metabolite(sugar,organic acid,amino acid,etc.)in pulp were determined by selecting 6 representative germplasms.Difference analysis and principal component analysis were conducted to evaluate the germplasm of watermelons and provide a scientific basis for the utilization of watermelon germplasm resources.The main conclusions are as follows:(1)There were rich diversity in stem,leaf,flower,fruit and seed characters of 8 watermelon germplasm resources.The variation coefficient of main agronomic traits of 8 watermelon germplasm resources ranged from 14.07% to 64.12%,and the biggest coefficient of variation was the single fruit weight,which was 64.12%,followed by marginal sugar content(52.63%)and central sugar content(45.61%).And 100-grain weight(44.25%),the smallest coefficient of variation was seed width(14.07%).A comprehensive evaluation of agronomic traits was carried out on 8 watermelon germplasm resources.(2)Five representative watermelon germplasms and cultivated watermelon ‘W1-1' were selected for metabolite principal component analysis.The results showed that cultivated watermelon,feed watermelon,medicinal watermelon and wild watermelon had different metabolite characteristics.Cultivated watermelon ‘W1-1' and wild watermelon ‘W1-51' have higher threose,glutamic acid,trehalose 6-phosphate,succinic acid,serine,mannose,galactose,citrulline,aspartic Amino acid content,in which the content of threose,mannose and galactose of the cultivated material ‘W1-1' is higher than that of wild watermelon ‘W1-51';the feed watermelon ‘947' and the medicinal watermelon ‘W1-60'have higher Glucose 1 phosphate,D-fructose 6 phosphate,L-malic acid,phosphoric acid,L-leucine content is higher,wherein;the content of ‘947' phosphoric acid for the feed watermelon is higher than that of medicinal watermelon ‘W1-60';medicinal watermelon ‘W1-49' is rich in galactinol,benzoic acid,anhydrous glucose,and sucrose.(3)The representative feed watermelon,medicinal watermelon,wild watermelon were compared with those of cultivated watermelon ‘W1-1' to metabolites,and the results showed that the content of carbohydrate metabolites in cultivated watermelon ‘W1-1' were compared with was high for feed watermelon,wild watermelon,medicinal watermelon.The content of salicin,pine triose O-rhamnosideand 2-hydroxy-4-methylvaleric acid in feed watermelon ‘1555' is higher than that of cultivated watermelon ‘W1-1'.The content of chlorogenic acid,D-alanyl-D-alanine,and gadolin triose O-rhamnoside in the fruit of wild watermelon ‘W1-51' was higher than that of cultivated watermelon‘W1-1'.The content of L-malic acid,salicin and 2-picolinic acid in medicinal watermelon ‘W1-60'was higher than that of cultivated watermelon ‘W1-1',and the content of chlorogenic acid in wild watermelon ‘W1-51' was higher than that of cultivated watermelon ‘W1-1',indicates that its antioxidant activity is higher than that of cultivated watermelon ‘W1-1'.