Abstract: Combining ability analysis of net photosynthesis rate at different Phase of flowering and fruit setting in pepper was made with 15 cross combinations from 6 parents by (1/2)n(n-1) diallel crosses. Results showed that there are relatively large differences in general combining ability (GCA) effect among different parents and at different phase of flowering and fruit setting and also relatively large differences in special combining ability (SCA) effect among different hybrids. There are relatively large GCA effects in late parents but relatively less GCA effects in early parents. No obvious laws are found in the relationship between SCA effects and mature of hybrids. Variances of SCA are larger than variances of GCA. Heritability is less but affection of environment is larger. Correlation analysis of combining ability between net photosynthesis rate and agronomic character or resistances to main diseases showed that correlation coefficients of GCA are relatively large at medium phase and late phase of flowering and fruit setting. Net photosynthesis rate is more relative to leaf characters and fruit characters. Correlation coefficients of SCA are relatively large at early phase and late phase of flowering and fruit setting. Net photosynthesis rate is more relative to leaf characters and plant characters at early phase but plant characters ant fruit characters at late phase. Correlation coefficients of SCA between net photosynthesis rate and resistances to main diseases are larger than correlation coefficients of GCA.

Key words: Pepper (Capsicum annuum L.), Net photosynthesis rate, Combining ability, Stabilization analysis, Correlation analysis