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Entre as espécies do gênero Passiflora, a P. foetida L. apresenta a maior variabilidade genética e tem grande importância medicinal, pois é usada no tratamento de doenças como asma, icterícia, e na forma de emplastros, para as erisipelas e doenças de pele com inflamação. Portanto, são necessários estudos que visem a micropropagação e conservação. As sementes de P. foetida L. apresentam dormência e muitas vezes, levam alguns meses para germinar, produzindo mudas desuniformes e de baixo vigor. Neste sentido, a cultura de tecidos apresenta-se como uma forma alternativa a propagação. Assim, o objetivo do trabalho foi estabelecer e micropropagar P. foetida L., para formação de um banco de germoplasma. Para tanto, sementes foram escarificadas, desinfestadas e inoculadas em meio MS(½) sem reguladores de crescimento e cultivados por 66 dias. Explantes de hipocótilos obtidos de plantas germinadas in vitro, foram cultivados no mesmo meio suplementado com 1,0 mg L-1 de BAP. Na fase de estabelecimento, 45% dos explantes brotaram e formaram gemas axilares. 88,9% dos explantes de hipocótilo induziram brotação e 11,1% produziram calos. Plântulas regeneradas com 1,82 cm de altura, com raízes foram aclimatadas.

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Melon or muskmelon (Cucumis melo L.) is of considerable economic importance in Brazil. Nearly all the cultivars currently grown are hybrids. Heterosis has been used to advantage in the melon plant, and the use of uniform hybrids is one of the reasons for successful cultivation. The aim of the present study was to evaluate the agronomic potential of yellow melon lines and hybrids. An experiment was conducted in randomized blocks with three replications to evaluate 24 hybrids generated by crosses among three elite lines used as female parents (AF-01, AF-02, and AF-03) and eight lines used as male parents (LAM-01, LAM-02, LAM-03, LAM-04, LAM-05, LAM-06, LAM-07, and LAM-08). Yield and fruit quality traits were evaluated. Partial diallel analysis was carried out to estimate general combining ability and specific combining ability. Additive and non-additive effects were observed for the yield, mean fruit weight, and pulp thickness traits. The lines AF-02, LAM-02, and LAM-03 are the most promising as parents as they more frequently have favorable alleles. The most prominent hybrids in diallel analysis were AF-02 x LAM-02, AF-02 x LAM-03, AF-02 x LAM-04, and AF-03 x LAM-06.

ABSTRACT. The objective of this study was to estimate the genetic effects on in vitro germination and development of chili peppers. For this, four genotypes were used as parents. They were crossed in a complete diallel scheme. The parents (4) and hybrid (12) seeds were germinated in glass bottles containing MS media. The following variables were evaluated: seed germination percentage, deformed seedlings percentage, radicle emission percentage, root length, root number, hypocotyl length, hypocotyl width, definitive leaf number, leaf length, and leaf width. The data were submitted to analysis of variance and the means were grouped by the Scott-Knott criteria (P ≤ 0.05). The diallel analysis was performed according to the Griffing method, method I, fixed model. Significant differences for all analysed variables were observed. Additive and non-additive effects were observed influencing the performance of the genotypes in relation to the evaluated variables. The genitor 132 showed the highest general combining ability for almost all evaluated characteristics, except seed germination percentage and deformed seedlings percentage. This study revealed dominance effects are responsible for genotypic variation for almost all evaluated traits. In addition, we found significant reciprocal effects for all studied characters. For the traits to which non-additive variances were important (germination percentage, deformed seedlings percentage, root number, hypocotyl length, hypocotyl width, and definitive leaf number, leaf length, and leaf width), there was an additional opportunity for developing F 1 hybrid.