| Soybean(Glycine max(L.))is an important oil and food crop,and it is planted in a large area in China.Soybean germplasm resources are important materials for studying the origin,heredity and evolution of soybean.The research of soybean germplasm resources in China started very early,but the utilization rate of landrace continued to decrease,resulting in the gradual narrowing of the genetic basis of soybean cultivars.In this study,1402 germplasm resources from different geographic and ecological types provided by the Institute of Crop Science of the Chinese Academy of Agricultural Sciences were used as experimental materials.Summer swoing experiments were conducted in Dangtu County,Ma’anshan City,Anhui Province in 2018 and 2019.It is proposed to use simple seed counting software to measure the uniformity of soybean seeds,and to exploring and optimizing the test procedure of soybean yield factor per plant.21soybean agronomic traits were investigated,and the agronomic trait performance of soybean germplasm from different geographic ecological types in Dangtu was compared.Based on the correlation analysis of the agronomic traits of soybean germplasm resource,principal component analysis and cluster analysis were carried out to classify the germplasm resources.Soybean germplasm with single,compound agronomic traits and comprehensive performance was selected as the breeding parents in Dangtu.The result are as follows:(1)Image-based optimization of soybean seed-testing process:The simple seed counting software can quickly determine the seed number and shape per plant,it can also measure the uniformity of the seeds in single plant.Both the seeds number per plant and the efficient pods number per plant are significantly positively correlated with the seed weight per plant within varietiy and among varieties,and the seeds number per plant and the efficient pods number per plant are also significantly positively correlated,therefore,it is proposed to quickly obtain the seed number per plant based on the image software counting,and combine with the seed weight per plant to indirectly calculate the 100-seed weight instead of manually counting the efficient pods number per plant and measuring the100-seed weight,after changing,it can save 40%time,measure 10 more seed traits,which improves the survey efficiency of soybean agronomic traits.(2)Influence of artificial evolution on agronomic traits of soybean resources:Among growth period traits,compared with the landraces,the day to flowering of the improved cultivars was shortened by 5.8 days and the day from flowering to maturity increased by 3.8 days,but there is no obvious change in the day to maturity.Among plant type traits,compared with the landraces,the plant height of the improved cultivars decreased by 22.2cm,the the bottom pod height decreased by 0.5cm,the efficient branch number decreased by 0.8,and the number of main stem nodes decreased by 2.7.Among yield composition traits,compared with the landraces,the node of main stem of the improved cultivars decreased by 11.2,the seeds number per plant decreased by 22.0,and the 100-seed weight increased by 3.1g,there was no significant change in the seed weight per plant.Among seed traits,compared with the landraces,the improved cultivars have similar seed size and coefficient of variation of seed size,the same ratio of seed length-to-width(1.3),and an increase in seed weight per porjection area of 0.076g/cm~2.(3)The agronomic performance of soybean germplasm resources from different ecological types in Dangtu summer sowing:Northeast spring sowing soybeans have the shortest days to maturity in Dangtu(91.8 days),the plants are smaller,but the 100-seed weight and seeds are larger;most of the northern spring sowing soybeans are landraces,their plants are larger when sown in Dangtu at summer,with the highest plant height(70.3cm),the highest efficient branch numbers(3.1 branches),and the highest node number of main stem(16.0 nodes),but the 100-seed weight is smaller;Huanghuaihai summer sowing soybeans have average agronomic traits in Dangtu,but the protein content is low(42.1%);Southern spring sowing soybeans have a shorter days to maturity(92.6 days)in Dangtu,the efficient pods number per plant and the seed number per plant are the largest(52.4 pods and94.5 seeds),the 100-seed weight and seed size are smaller,and the oil content is the lowest(42.1%);southern summer sowing soybeans have the longest days to maturity in Dangtu(100.9 days),with larger plant,higher plant heights(69.2 cm),bottom pod heights(9.0 cm),and the largest node number of main stem(16.0 nodes),high seed weight per plant,100-seed weight and plot yield are 12.7 g,15.5 g and 448.0 g respectively;foreign spring sowing soybeans come from all over the world,and their performance in Dangtu is relatively even.Because the environmental conditions and sowing season of the source are similar to the experimental conditions,overall performance of Huanghuaihai summer sowing soybeans and Southern summer sowing soybeans is most suitable for summer sowing planting in Dangtu.(4)Correlation of agronomic traits and resource clustering:Among landraces,the day to flowering,the day to maturity and the efficient branch number have low correlation with traits such as efficient pods number per plant,seeds number per plant and seed weight per plant,the seed weight per plant has low correlation with traits such as the node number of main stem,the efficient pods number per plant,and the seed number per plant.In improved cultivars,the correlation coefficients of these traits increased.There is no significant correlation between the bottom pod height of landraces and the efficient pods number per plant and the seed number per plant,but these two pairs of traits are extremely significantly negatively correlated in improved cultivars.Most landraces are divided into cluster I,and most improved cultivars into clusterⅡby cluster analysis.(5)Selection of excellent soybean germplasm in Dangtu:According to the average performance of the two-year agronomic traits of the germplasm resource group,the varieties with extreme performance of each trait were selected;a batch of soybean germplasm with excellent performance in compound agronomic traits such as high-yield and early maturity,high 100-seed weight and yield per plant,more efficient pods number per plant and seed number per plant,double high oil and protein content,etc.,can be used as donor parents for soybean breeding in middle and lower Yangtze River;at the same time,a batch of soybean germplasm with excellent comprehensive performance in Dangtu was selected as recipient parents for breeding. |
PDF Full Text Request