The Inheritance Analysis Of Main Agronomic Traits About The Hybrids From The Self-Fertile Buckwheat

Heterostyly is a genetic manifestation of crops during evolution.The morphologic characteristic of heterostyly showed that different heights of stigmas and anthers,which is widely distributed among angiosperm plants,including buckwheat.Common buckwheat has self-incompatibility,yet homostylic common buckwheat has self-compatibility,and have a high setting percentage.Although lots of reports have been published on the yield-related traits of buckwheat,the traditional studies of yield traits have a genetic complex,and the phenotypic selection efficiency is not high,and the yield increase is not obvious.The heterostylous buckwheat is a kind of special characters can be inherited stably,so it can sharply increase the yield of common buckwheat if the homostylic common buckwheat is used for improving common buckwheat breed.In this study,we focus on the 3 hybrids which date from hybridization between common buckwheat and homostylic common buckwheat,and investigate the segregated types,segregated rate of style character and genetic traits of agronomic traits.The main results are as follows:?1?The F₂ hybrids of different cross combination separate into 4 same style types, which are homostylic type,pin type,short pin type and long thrum type.F₅ generation and F₇generation have 5 kinds of style types,which are homostylic type,pin type,thrum type,short pin type and long thrum type.In all these three generations,homostylic type accounts for the largest proportion,which are 71.2%,60.8%and 74.7%respectively.Other types of style have different portion in different generations,but in high generations?F₅,F₇?,pin type and thrum type always account for the smallest proportion.The effect of selection is very obvious.?2?In three different generations,the average self seedset rate of homostylic type and long thrum type are 18.2%-21.2%and 16.5%-22.5%respectively,which are obviously higher than that of short pin type,pin type and thrum type,belonging to high self seedset rate range,and there is no significant difference between homostylic type and long thrum type.The average self seedset rate of pin type and thrum type are 2.3%-3.3%and 1.0%-2.9%separately,and are both lower than 5%;The self seedset rate of short pin type in three generations are4.5%-8.0%,which are significantly lower than that of homostylic type and long thrum type,and there is no obvious difference between short pin type,pin type and thrum type.As a result,we can put short pin type,pin type and thrum type into self-incompatibility type or low self-compatibility type.?3?We compared 6 agronomic traits in the F₂ generation,plant height showed Over-LP heterosis prominently;number of nodes and number per flower less than the average of parents,branch slightly higher than the mean of parents.In the 9 main characters,third branch,grain number,grain weight showed very high coefficient of variation,belongs to the high and wide variation of traits.The number of flowers and second branch of the average CV about70%,belonging to moderate variation.Plant height,number of node,primary branch,1000-grain weight of the average CV is about 20%,belong to low trait variation.With the generation increasing,because of the selection pressure the coefficient of variation of some characters including plant height,node number,number of inflorescences per plant,grain number and grain weight per plant showed decreased,which mean that these selections of characters were effectively.Generation variance analysis showed that it is better to select the traits of plant height,node number,primary branch,1000 grain weight in early generation.?4?We can study from the correlation analysis of hybrid style buckwheat and common buckwheat after type traits,agronomic traits,agronomic traits and yield traits and yield and yield traits had significant or very significant correlations.Grain weight per plant and grain number per plant was positively correlated,correlation coefficient was 0.992**;secondly,grain weight per plant,grain number per plant and the number of flower is very significant positive correlation,the correlation coefficient is 0.674**,0.671**;third,number of flower per plant and plant height,node number and branch level between highly significant positive correlation,the coefficient were 0.462**,0.474**and 0.581**;between plant height and number of node also had very significant positive correlation,the correlation coefficient is0.493**.Therefore,according to the correlation between characters of breeding selection is effecting.