In plateau region of Yunnan Province, japonica rice-growing areas are characterized by high altitude, heavy rain in summer, low temperature and insuffi- cient accumulated temperature in grain-filling stage. In view of...In plateau region of Yunnan Province, japonica rice-growing areas are characterized by high altitude, heavy rain in summer, low temperature and insuffi- cient accumulated temperature in grain-filling stage. In view of the characteristics above, the breeding of japonica soft rice was carried out. In this paper, the yield and quality characteristics of japonica soft rice cultivars bred recently in Yunnan Province were analyzed. The results showed that there was no difference in milling quality, but there were great differences in chemical indexes between soft rice and japonica rice, such as amylose content. For example, in soft rice, the amylose con- tent was significantly lower, but the protein content, gel consistency and taste meter value were significantly higher compared with those in japonica rice. However, there was no significant difference in alkali digestion value between soft rice and japonica rice. The starch RVA profile characteristics of soft rice were significantly better than those of japonica rice. The RVA starch profile of soft rice showed higher maximum viscosity, lower minimum viscosity, higher breakdown value, lower final viscosity, lower setback value and shorter time to reach the maximum viscosity （P〈0.05, P〈 0.01）. The analysis of yield and yield components showed that the yield of japonica soft rice was still lower than that of the control cultivar, which might be caused by weaker tillering capacity, less grains per panicle and lower 1 000-grain weight. In addition, the approaches to improve grain quality and yield of japonica soft rice were also discussed.展开更多
基金Supported by Project of Yunnan Provincial Science and Technology Department(2012BB013)National High Technology Research and Development Program of China(863 Program)(2014AA10A603)Technology Innovation Training Project of Yunnan Province(2010CI075)~~
文摘In plateau region of Yunnan Province, japonica rice-growing areas are characterized by high altitude, heavy rain in summer, low temperature and insuffi- cient accumulated temperature in grain-filling stage. In view of the characteristics above, the breeding of japonica soft rice was carried out. In this paper, the yield and quality characteristics of japonica soft rice cultivars bred recently in Yunnan Province were analyzed. The results showed that there was no difference in milling quality, but there were great differences in chemical indexes between soft rice and japonica rice, such as amylose content. For example, in soft rice, the amylose con- tent was significantly lower, but the protein content, gel consistency and taste meter value were significantly higher compared with those in japonica rice. However, there was no significant difference in alkali digestion value between soft rice and japonica rice. The starch RVA profile characteristics of soft rice were significantly better than those of japonica rice. The RVA starch profile of soft rice showed higher maximum viscosity, lower minimum viscosity, higher breakdown value, lower final viscosity, lower setback value and shorter time to reach the maximum viscosity （P〈0.05, P〈 0.01）. The analysis of yield and yield components showed that the yield of japonica soft rice was still lower than that of the control cultivar, which might be caused by weaker tillering capacity, less grains per panicle and lower 1 000-grain weight. In addition, the approaches to improve grain quality and yield of japonica soft rice were also discussed.
