Genetic analysis of androgenic response in three culture media, recommended for tomato anther culture, was carried out using four parental lines crossed as half dialleles. Percentages of callus formation and shoot regeneration as well as callus diameter (as a measure of callus growth rate) were assessed. Analysis of variance indicated significant differences between the genotypes, culture media and their interactions for all traits. Hence, the effects of general and specific combining ability (GCA and SCA) for these traits were estimated and tested. Significant GCA mean squares observed (p<0.05) were as in the followings: all traits in M1 medium, shoot regeneration in M2 medium, and shoot regeneration as well as callus diameter in M3 media. The GCA variances were higher than those of SCA. Narrow sense heritabilities for percentages of callus formation and shoot regeneration ranged from 65 to 93. These additive genetic effects appeared to control these traits. The SCA variances were significantly higher than GCA variance only in callus diameter in M2 medium (p<0.05). Based on this finding, the callus growth seems to be controlled by non-additive genetic effects in M2 medium. Among the lines examined, Micro-Tina and MSK8 exhibited positive and significant GCA for callus formation as well as shoot regeneration. These lines may be recommended for an improvement in another culture responsiveness in tomato.
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