Comparison Of The Root Characteristics Among Different Soybean Varieties

Root system plays an important role in the growth the plant, but the research on soybean root system is very limited. In pot experiment, we studied the differences of root characteristics among soybean varieties, which had different traits and belonged to different ages and regions. The 43 soybean varieties tested came from Heilongjiang and Jilin province. The purpose of the study is to recognize the differences of root characteristics and to reveal the evolutionary trend of root system among different kinds of soybean varieties and to provide basic information for the soybean root breeding. The following is the results of the study:1 .There were differences in the root characteristics among soybean varieties of different ages. From 1950s to 1990s, the value of every main root characteristics increased with the advance of ages. The root system of the varieties in 1 990s was relatively well developed compared with that of the varieties in other ages. The evolutionary trend for the root system of soybean varieties was increase in root weight, root volume, root surface and length of lateral roots.2.There were differences in the root characteristics among soybean varieties of different regions in Heilongjiang province. The root system of the varieties in Harbin region was relatively well developed, the next was that of the varieties in Nenjiang region, the root system of the varieties in Jiamusi region was less developed compared with that of the varieties in Habin and Nenjiang region, while the root system of the varieties in Heihe region was relatively least developed.3 .There were differences in the root characteristics among soybean varieties of different traits. The drought resistant soybean varieties had a relatively well-developed root system compared with the water-fertilizer favorite varieties. The former had more root weight, larger root volume, stronger root absorbing capacity ,longer length of taproot and lateral roots.4.There were differences in the root characteristics among soybean varieties of different maturities. The root system of the later maturing varieties was well developed ,the next was that of the medium maturing varieties, while the root system of the early maturing varieties was relatively least developed.5 .There were differences in the root characteristics among the soybean varieties of different bearing habits. The sub-determinate soybean varieties had a relatively well-developed root system compared with that of the indeterminate soybean varieties. The former had more root weight, larger root volume, more root surface, longer length lateral roots and wider hypocotyl.6.There were correlations bet~veen the characteristics of roots and upperground parts of the soybean varieties .Root fresh weight, root volume, root dry weight, length of lateral roots, diameter of taproot, diameter of hypocotyl were close correlated with the diameter of stem, shoot fresh weight, shoot dry weight of the upperground parts respectively. The diameter of stem and shoot dry weight could be used as index for selecting roots in soybean breeding.Postgraduate:Yang Xiuhong Major: Crop Genetics and DreedingSupervisor:Prof. WuZongpu Prof. ZhangGuodong...