RESUMO
Inheritance of plant height, pod length, pod width, seed length and seed width was studied in a set of crosses grown during rabi 2007-08. F2 phenotypic data for plant height was a good fit to a phenotypic ratio of 1:4:6:4:1 and 1:2:1 respectively in two crosses studied indicating the involvement of more than two genes. Segregation of pod length in F2 generation of the cross ICGV 00350 x K 1340, was a good fit to a phenotypic ratio of 45 medium short : 19 long pods while in the cross ICGV 00350 x TG 37A segregation of pod length was a good fit to a phenotypic ratio of 1 long : 2 medium : 1 short pod length. Segregation of pod width in the crosses ICGV 00350 x K 1340 and ICGV 00350 x TG 37A presented a good fit to a phenotypic ratio of 3 high width: 1 medium width pods, while in the cross ICGV 00350 x Jyothi, F2 segregation data was a good fit to a phenotypic ratio of 1 high width: 2 medium width: 1 low width pods. F2 segregation of seed length in the cross ICGV 00350 x K 1340 was a good fit to a phenotypic ratio of 13 long medium: 3 short. Segregation of seed width in F2 generation of the crosses K 1340 x TCGS 888 and K 1340 x Narayani was a good fit to a phenotypic ratio of 15 medium low : 1 high width and 3 low : 1 medium width seeds.
RESUMO
The greenhouse whitefly, Trialeurodes vaporariorum Westwood, is the most common and abundant whitefly in Argentine horticultural greenhouse crops, especially in tomato (Solanum lycopersicum). Resistance in some wild tomato relatives, such as S. peruvianum, S. habrochaites and S. pennellii to the greenhouse whitefly has been described. The Mi gene confers effective resistance against several species of insects, among them the sweet potato whitefly, Bemisia tabaci Gennadius. Resistance to T. vaporariorum was found in the prebreeding line FCN 93-6-2, derived from a cross between S. lycopersicum cultivar Uco Plata INTA (MiMi) and the wild line FCN 3-5 S. habrochaites. The purpose of this study was to evaluate resistance to T. vaporariorum in tomato genotypes and to study the relationship between this resistance and the presence of the REX-1 marker, which is linked to the Mi gene. In a free-choice assay, the average number of adults per leaf and the number of immatures on the middle and basal plant parts were analyzed. In a no-choice assay, the oviposition rate and adult survival rate were calculated. For all variables analyzed, FCN 3-5 was the most resistant strain. Variations were found in the F2 progeny between the prebreeding line FCN 13-1-6-1 and cv. Uco Plata INTA. Results from the F2 progeny indicate that resistance to T. vaporariorum may be polygenic with transgressive segregation. Whitefly resistance was found to be independent of the REX-1 marker.