Abstract：Abstract：Phaseolus vulgaris phytohaem agglutinin（PHA）is an important plant anti-nutrient factor，and also a major chemical component of food poisoning in common bean．At earlier stage of this study，on the basis of detecting PHA content of commercial matured pods from 233 common bean accessions，we selected
6 varieties with obvious different PHA contents as parents，and constructed 4 hybrid combination F1 and F2 genetic populations by artificial hybridization and progeny cultivation．At the same time，field experiments on hybrid parents and various genetic populations were conducted．PHA contents of each single commercial
mature pods were tested，and genetic traits analysis was conducted．The results indicated that the variation of PHA content in commercial pod among individual plants in F1 population was small．But the strength of hybridization superiority after crossing with different parents became obviously different．The dominant degree
analysis revealed that this character was incomplete dominant inheritance of single parent．In F2 population，the PHA contents in single commercial pod presented extreme differences，indicating in F2 this character demonstrated obvious segregation，and the segregation degrees beteen different combination were different．
The main peak of individual frequency distribution curve in F2 population depending on PHA content was obvious distinct，but deviated from the mid-parent value．A few individual plants were distributed in the 2 tail areas，indicating that single plants with rather extreme PHA content were separated from this generation，
which had provided opportunities for developing varieties with high or low level PHA．The heritability of PHA content in common bean was over 95%，suggesting that the relevant genotype effect had played a crucial role in decision of this character．Therefore，the PHA content character in common bean belonged to quantitative
genetic character，mainly controlled by gene．This experiment screened 6 single plants with excellent and comprehensive characters from recombination of extreme low PHA content seperated from F2 population，thus realizing the innovation of common bean germplasm with low PHA content．
