Seleção entre e dentro de famílias F3 para resistência ao etileno em pimenteiras ornamentais (Capsicum annuum L.)

• Autor(a) principal: Vasconcelos, Giovana Patrícia Sales de
• Data de Publicação: 2017
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/14400
• topic: Etileno; Longevidade pós-produção; Pimentas; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA

The pepper plant belongs to the Solanaceae family and the genus Capsicum, comprising between 33 and 34 species, which represent a large and diversified number of plants, being widely grown throughout the world due to the wide variety of products, uses, forms of consumption and ornamental attributes. However, despite the commercial value attributed to peppers, handling procedures and post-harvesting, are still unknown, especially when referring to linked factors to post-production, especially related to the sensitivity of these to ethylene hormone. This study aimed to research the genetic diversity and the sensitivity of ornamental pepper plants, (Capsicum annuum), in F3 families. After reaching a marketing point, when the pepper plants presented at least 70% of the ripe fruits, the plants were transferred from the greenhouse to the laboratory and the evaluation of the following variables was carried out: counting of leaves, counting of fruits and content of chlorophyll. Subsequently, the plants were stored in hermetic chambers, with a capacity of 60 l, containing 10μL L-1 (PPM) of ethylene gas. The counts were performed prior to treatment and after a period of 48, 96 and 144 hours of exposure to ethylene hormone. The experimental design used was entirely randomized, with a 11x3 factorial arrangement (seven families x four witnesses x 3 times) to evaluate the sensitivity of peppers to the hormone. For the evaluation of genetic diversity, the Tocher grouping method was used. It was observed that there was interaction for chlorophyll B, with no interaction for the characteristic leaves, fruits and chlorophyll A. For the variable chlorophyll a and leaf abscission there was significance both for family and for exposure time (p ≤ 0.01), on the other hand, for fruit abscission was observed significance only for time. The 35 family and the witnesses 77.3, 134.1 and Calypso, presented the biggest losses of chlorophyll B, in the 96h of exposure to ethylene already. In terms of sensitivity to ethylene hormone, the 35 family was the one that presented more sensitive to all the variables analyzed. The biggest loss of leaves and the largest waste in the content of chlorophyll A occurred in 144h time. The families presented different levels of sensitivity to ethylene hormone. With respect to genetic diversity, it was possible to observe, by the method of optimization of Tocher, that there is variability, in the families studied, for factors related to post-production. The families UFPB17 and UFPB 47 were the ones that presented greater formation of groups: eight groups, in contrast, the family UFPB 56 was the one that presented the smallest formation of groups: only three. The family UFPB 35 formed seven groups. The families UFPB 55, UFPB 53 and UFPB 30, formed five groups. By Singh's method, it was possible to identify, that the abscission characteristic of leaves was the one that contributed most to the genetic divergence found in most families. However, the characteristic that contributed less to genetic divergence, for most families evaluated, was the variable abscission of fruit. All the families studied, presented genetic diversity, by the method of Tocher, for the analyzed variables.