الفهرس 
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Abstract
This study was carried out through the period from 2007 to 2009 at Mallawy Agricultural Research Station, to study the general, specific combining ability, estimates some genetic parameters and correlation coefficient among the studied characters of five cherry tomato lines imported from two sources; four from Asian Vegetable Research and Development Center (AVRDC) and one from United States, Department of Agriculture (USDA):
1- CLN1558B (P1) 2- CLN1555B (P2) 3- CH 154 (P3)
4- CH 157 (P4) 5- 02L1058 (P5)
Highly significant differences were obtained among the studied genotypes for all the studied traits. The parents had highly significant differences for all studied traits, confirming the presence of additive effect except number of locules and number of branches per plant for the parents. Mean squares due to crosses exhibited highly significant differences for all studied traits except with total soluble solids was showed significant differences. The pH mean squares was insignificant. These results indicating the presence of non-additive gene effect.
Analysis of variance revealed that both general combining ability (GCA) and specific combining ability (SCA) mean squares were highly significant for all studied traits, except the pH trait which was insignificant for GCA. These results indicated that the importance of both additive and non-additive gene actions in the inheritance of these traits. The inheritance of this trait was controlled by non-additive gene action. The obtained results were summarized as follow:
Conclusion:
In general, developing improved cherry tomato hybrids requires a careful evaluation and screening the parental genotypes. Evaluations of new pure lines per se and in crosses are the first step to determine the relative combining of appropriate heterotic crosses as potential sources of pure lines. However, further studies needs to be conducted in the future on the parental lines number one, two and five, which participated in the best yielding crosses (P1 × P2) and (P1 × P5) are recommended for starting a breeding program.