Comprehensive Evaluation Of Agronomic Traits,Disease Resistance And Quality Traits Of 40 Sweet Potato Germplasm Resources

The cultivation of high-quality and high-yield sweet potato varieties is inseparable from abundant sweet potato germplasm resources,since the introduction of sweet potato in my country,there has been more than 400 years of cultivation history,and abundant germplasm resources have been accumulated.There are many studies on the correlation between sweet potato agronomic traits and yield,the screening of sweet potato resistance to diseases and insect pests,and the analysis of nutritional quality,but the comprehensive appraisal and evaluation of its agronomic traits,quality traits and resistance is less.Therefore,this experiment comprehensively analyzed and evaluated the main agronomic traits,black rot resistance and quality traits of 40 sweet potato germplasm resources,and provided theoretical basis for sweet potato breeding,quality improvement and processing.The main conclusions are as follows:1.According to the analysis of the 7 agronomic traits of 40 sweet potato germs,it was found that there were large differences in different varieties in their agronomic traits,and the variation coefficients of 7 agronomy traits fluctuated between 18.24% and 36.48%,with the average single potato weight,single plant yield,and longest vine length having larger coefficients of variation,indicating that the tested varieties had great potential for genetic improvement in these traits;Correlation analysis showed that the yield per plant was extremely significantly positively correlated with the longest vine length,number of tubers per plant,percentage of large and medium tubers and average single tuber weight(P<0.01),and positively correlated with stem diameter and number of base branches;Through grey correlation analysis,it was found that the correlation degree between individual plant yield and other agronomic traits,from highest to lowest,were as follows: average single potato weight>longest vine length>large to medium potato rate>number of potatoes per plant>stem diameter>number of basal branches;Through membership function analysis,it can be concluded that Qining 21 has the best comprehensive performance in agricultural traits.2.Through the identification of black rot resistance in 40 sweet potato germplasm resources,2 varieties with high resistance,namely Qinshu 5 and Qinshu 6,33 resistant varieties,2 susceptible varieties and 3 highly susceptible varieties were screened out,which provided rich black rot resistance resources for sweet potato breeding and production.3.According to the analysis of the 7 quality traits of 40 sweet potato varieties,it was found that the variation range of quality traits in different varieties was significant,with the variation coefficients of 7 quality traits fluctuating between 11.93% and 170.02%.Among them,the variation coefficients of anthocyanins,flavonoids,chlorogenic acid,and total phenol content were relatively large,indicating that these traits can provide a genetic resource basis for improving sweet potato quality traits.Through correlation analysis,it was found that there was a highly significant negative correlation between dry matter content and reducing sugar content(P <0.01),a highly significant positive correlation between soluble protein content and total phenols,flavonoids,chlorogenic acid,and anthocyanin content(P<0.01),and total phenols,flavonoids,chlorogenic acid and anthocyanin content were positively correlated with each other.The variety with the best comprehensive performance of quality characters was Xu Zishu 8;The principal component analysis showed that the total phenolic content and dry matter content could be as the main indicators to evaluate the quality traits of sweet potato.4.The agronomic traits,disease resistance and quality traits of 40 sweet potato germplasm resources were comprehensively evaluated using principal component analysis.The results showed that the average single potato weight,number of basal branches,stem diameter,total phenolic content,dry matter content,anthocyanin content and disease rot diameter contributed significantly to the comprehensive evaluation of sweet potato germplasm resources,which could be used as an important index to evaluate the comprehensive evaluation of sweet potato germplasm resources.The top five varieties in comprehensive evaluation were Chuan Zishu 6,121828,14315,Qi Ning 21 and Xu Zishu 8.This study conducted a systematic analysis and comprehensive evaluation of 40 sweet potato germplasm resources,providing a theoretical basis for the breeding objectives of different uses of sweet potato varieties.