| The mechanism of cultivation measures to water use efficiency of soybean in dryland through nitrogen use, Phosphorus use, irrigation and membraning methods, and the varieties identification and RAPD analysis on drought tolerance were conducted in this paper, in order to provide suitable cultivation measures and varieties and improve soybean production in rainfed areas in western China. The main results of trials are the following:1. Increase nitrogen use could improve water use efficiency in soybean. In dry-land, more nitrogen use can make up the harmless of dry to plant growth, improve the photosynthesis index, drought tolerance indices and root development, and finally increase WUE and yield. But it was not suitable to much using of nitrogen. Otherwise, it can result in the negative effects. The three treatments of nitrogen were 27 kg/hm2 (N1), 72kg/hm2(N2), 117kg/hm2 (N3). The water use efficiency and yield of N2 were the largest, and next was N3, the N1 was the smallest, the yield of N2 were 24.41% larger than N1, the water use efficiency of leaf, soil and rainfall in N2 were 6.22%, 24.26% and 24.29% higher than N1.2. Increase Phosphorus application could accelerate soybean growth under water stress condition. It slowed the decreasing of plant height, leaf area, vegetative development, pods per plant and yield under water stress condition. Increasing P application can reduce those bad effects of water stress. P nutrition increased soybean's root vigor, decreased stoma conduction of leaves and transpiration rate, increased the CO2 content among cells, photosynthetic rate and enhanced the water use efficiency; it also improve the content of free praline, relative water content in leaves and activities of anti-oxidative enzymes (POD,SOD,CAT), decrease the relative electric conductivity and MDA. It was also showed water stress in initial flowering stages effects on yield greatly.3. Membraning could improve WUE of soybean significantly. Using membraning inline and between line can improve the growth of soybean, the LAI, photosynthesis index, drought tolerance, root development and water movement and using by root. The yield of membraning inline increased 20.85% than CK, LWUE, SWUE and RWUE increased105.16%, 150.00% and 20.43%,the yield of membraning between line increased 16.67% than CK, LWUE, SWUE and RWUE increased112.68%, 141.76% and16.98%.4. Identification and analysis on drought resistant characters of different soybean varieties. According to the dependence function analysis, the soybean varieties were differentiated four types: high drought resistance are Fengyuan 001-44, Mengdou 9, Jindou 25, Jindou 23, Dadouqiu 9300, semi-wild soybean, Moshi soybean, Jiyu 39 and Jindou 15; general drought resistance are Mengdou 19, Heinong 46, Heihe 38, Suinong 10, MT9911-2, Jiyu 62, Jiyu 47, Wangzhongwang, Jiyu 56, Bainong 10, Jiunong 20, Jiyu 55, Xing 00-5091 and Jiyu 35; middle drought resistance are Mengdou 17, Neidou 4, Jiangmodou 1, Heinong 18, Mengdou 12, Kangxian 4 and Zhongzuo 122; low drought resistance are Zhahuanglv, Mengdou 18, Mengdou 16, Hefeng 47, Jiyu 38, Zhongzuo 962 and Zhongzuoyin 1. And the drought resistant characters of different soybean varieties were also analyzed using SPSS, it has the same results for 77.8% varieties.5. Genetic diversity of soybean varieties using RAPD method. By the selection of 45 pieces of primers, 12 primers could amplify polymorphism patterns, the polymorphism patterns were amplified for 85.2%. The results showed that the amplified patterns were different in primers, that the amplified patterns form different primers were also different. The primers of S183 and S189 could distinguish the soybean varieties well, and it showed the same results with dependence function analysis by SPSS. The above results provide foundation for future soybean breeding.
|
PDF Full Text Request