ABSTRACT
Ensaios foram realizados no campo visando avaliar a atratividade e a não-preferência para oviposição da mosca-branca Bemisia tabaci (Genn.) biótipo B por genótipos de abobrinha (Cucurbita pepo) e também observar a sensibilidade dos genótipos (Novita, Sandy, Caserta Cac Melhorada, Novita Plus, Samira, Bianca, AF-2858 and Caserta TS) ao sintoma de prateamento foliar. O genótipo Sandy foi o menos atrativo à mosca-branca, enquanto que Novita Plus, AF-2858 e Samira foram os mais atrativos. O genótipo Caserta Cac Melhorada foi o menos ovipositado. Os genótipos Sandy e AF-2858 foram os mais produtivos, com as maiores médias de frutos produzidos. Os genótipos Sandy e Caserta Cac Melhorada apresentaram os menores índices de sintoma de prateamento foliar.
Field assays were performed to evaluate the attractiveness and the non-preference of whitefly Bemisia tabaci (Genn.) biotype B for oviposition on squash genotypes (Cucurbita pepo) and to observe the susceptibility of genotypes (Novita, Sandy, Caserta Cac Melhorada, Novita Plus, Samira, Bianca, AF-2858 and Caserta TS) to silverleaf symptoms. The Sandy genotype was the least attractive to whitefly, while Novita Plus, AF-2858 and Samira were the most attractive. The Caserta Cac Melhorada genotype was the least preferred for oviposition. The Sandy and AF-2858 genotypes were the most productive, with the highest mean of fruits produced. The lowest silverleaf symptoms index was observed for the Sandy and Caserta Cac Melhorada genotypes.
Subject(s)
Animals , Cucurbita/genetics , Cucurbita/parasitology , Hemiptera/physiology , GenotypeABSTRACT
The inheritance of the tendency to set parthenocarpic fruit in the summer squash (Cucurbita pepo L.) line Whitaker was studied. Two parental lines, Whitaker (parthenocarpic) and Caserta (non-parthenocarpic), and the F1 and F2 generations and backcrosses to both parents were tested. The parthenocarpic tendency of individual plants was scored on a scale from 1 (non-parthenocarpic fruit) to 5 (parthenocarpic fruit). The Whitaker line produced parthenocarpic fruit and had a mean score of 4.2, whereas Caserta did not set parthenocarpic fruit and had a score of 1.55. The heritability estimates indicated that genetic gains from selection were feasible. The additive-dominant model showed a good fit, with epistasis being negligible or nonexistent. The hypothesis of monogenic inheritance with incomplete dominance was not rejected within the degree of dominance range from 0.2 to 0.5. These results indicate that parthenocarpy is controlled by a single locus, with incomplete dominance in the direction of parthenocarpic expression