Genetic Variation Of Correlative Characters Of The Response To Temperature In Soybean

Soybean[Glycine max(L.) Merr.]variety is sensitive to temperature and photoperiod, which account for its narrow plant area.The previous studies of predecessor showed that growth of soybean could be accelerated by high temperature and short day,whereas,low temperature and long day slow it.157 soybean varieties which comes from different ecological regions and the RIL population of NJRIKY were used to study the response to temperature in this research.This paper consists of identification methods and evaluation indexes of temperature response,genetic variation in correlated characters,and inheritance analysis of temperature response.The main results were as follows:1 This study on the evaluation indexes of temperature response of soybean was carried by control the day length at the field.The results indicated that Standard difference(S), Relative coefficient(R),Variation coefficient(CV),Temperature difference percent value (TD),and Membership function value(F_i) reflected the response to different temperature conditions of soybean.The TD value and F_i value were better than the others.2 This study using TD as the evaluation index to identify and grade these gemplasm which were from different sources.The result showed the growth period of 8 soybean varieties were insensitive to temperature,as 5.10%,and most of the rest were more insensible or intermediate types.The family lines of RIL population represented super the high parent or inferior the low parent,and the proportion of the extreme types is big.3 About 157 landraces of total ecotypes of soybeans from China were used to study the difference of responses to temperature conditions of soybean ecotypes.This paper was aimed at the comparison among ecotypes on basis of the responses of days to flowering or maturating and plant characters.The temperature response difference value percentage(TD) was used as evaluation index.The results showed that there were significant differences among the major characters of different soybean ecotypes,and also showed that much difference in response to temperature among the tested cultivars in the same eco-region. The TD values in Ve-R₁ of cultivars from eco-regionâ… was -30.63%.The TD values in Ve-R8 of cultivars from eco-regionâ… was -15.03%.The TD values in Ve-R₁ and Ve-R₈ of cultivars from different eco-regions were significant.In addition,the TD value in plant height of cultivars from eco-regionâ… was -20.75%,the minimum.In all,plant height and branch could be as identification indexes to reflect the response of cultivars to temperature.4 Genetic segregation analysis of response to temperature of soybean was studied with the RIL population of NJRIKY,which were derived from the soybean(Glycine max(L.) merr.) parents "Kefeng1"×"Nannong1138-2"consisting of 184 inbred lines.The major gene and poly-gene mixed inheritance model was used to study the genetic segregation. The result showed that the response to temperature of soybean was controlled by three major genes,with additive plus additive×epistatic effects and without poly-genes effects (the F-1 model).The major genes effects values is 220.07,and the heritability values of the major genes were estimated as 92.66%.