Analysis Of Characteristic Variation Of Indica Hybrid Rices At Different Types Of Indica Planting Region In Yunnan

One of the most important food crops in Yunnan province is rice which distributed in a variety of ecological environment.For indica rice,there are three types of indica planting regions distribution at an altitude of about from 100 m to1500m,including double-season indica rice region located at below 1100 m,one-season indica rice region about 1100-1300 m and indica-japonica crosses region around 1400 m.Many researches showed that rice characters could be affected by different planting environment,but it is not repoted for the variations of indica rice traits planted at different types of indica rice planting regions in Yunnan.In this study,it was analyzed the twelve traits of forty indica hybrid rice combinations planted at three different types of indica rice planting regions in 2014 and 2015 years.The results of the research were follows: 1)there were detected significantly differences for variontions of four agronomic traits of these indica rices grown at the three different types of indica rice planting regions.The trends of the four traits(whole growth period,plant high,panicle length and effective tiller)between double-season and indica-japonica crosses regions were all opposite,and for one-season region the variation ranges were all between the previous two types of rice regions.2)There were also detected significantly differences for variontions of four economic traits of the indica rices grown at the three regions.Average values of the four traits of total grains per panicle,seed setting rate,1000-grains weight and yield at the two regions of double-season and one-season were all higher than of those at the indica-japonica crosses region.3)There were also detected significantly differences for incidences of four disease resistance traits of the indica rices grown at the three regions.There were very severe for the four diseases of leaf blast,neck blast,bacterialleaf light and banded sclerotial blight at the double-season region,and relatively light at the one-season region.However,it was most severe for the neck blast at the indica–japonica crosses region;4)Mostly rice combinations were grouped according to different planting regions,and especially more than 90% combinations were grouped at the indica-japonica region.In word,there was significantly difference for comprehensive performance of these indica rices among the three different types of indica rice planting regions,and it was also verified from their yield traits.For example,five rice combinations were the highest yield at the double-season region,but the probability of occurrence of the same five combinations from the other two regions of one-season and indica-japonica crosses were only 40% and 20%,respectively.Therefore,it is very difficult to select excellent indica rice at the two regions of double-season and indica-japonica crosses at the same time.The research result would provide theoretical reference for the ecological breeding and regional testing for indica rice in Yunnan.