Divergência genética entre cultivares comerciais de repolho quanto à preferência do pulgão‑da‑couve

Abstract

Resumo -O objetivo deste trabalho foi avaliar a divergência genética entre cultivares de repolho quanto à preferência alimentar do pulgão-da-couve (Brevicoryne brassicae). O experimento foi realizado com 27 cultivares, em casa de vegetação, com determinação da preferência do afídeo em ensaios com ou sem chance de escolha. Utilizou-se o delineamento de blocos ao acaso, com 27 tratamentos e cinco repetições. Estimaram-se as distâncias generalizadas de Mahalanobis e as cultivares foram agrupadas pelo método de Tocher, com formação de sete grupos. As cultivares Chato de Quintal, Ryuho e Taishita foram as menos preferidas pelo afídeo. A distância máxima foi verificada entre as cultivares Das 4 Estações e Suki, e a mínima ocorreu entre Chato de Quintal e Astrus Plus. O número de ninfas é a variável que permite maior diferenciação entre as cultivares. Há variabilidade entre as cultivares comerciais de repolho quanto à preferência alimentar do pulgão.Termos para indexação: Brassica oleracea, Brevicoryne brassicae, interação planta-inseto, mecanismo de resistência, preferência alimentar. Genetic divergence between cabbage commercial cultivars as to cabbage aphid preferenceAbstract -The objective of this work was to evaluate the genetic divergence between cabbage cultivars, concerning the feeding preference of cabbage aphid (Brevicoryne brassicae). The experiment was carried out with 27 cultivars, in greenhouse, where the aphid preference was determined in assays with or without choice. A randomized block design was used with 27 treatments and five replicates. Mahalanobis´ generalized distances were estimated and the cultivars were grouped by Tocher´s method with seven groups formed. 'Chato de Quintal', 'Ryuho', and 'Taishita' were the less preferred cultivars by the aphid. The maximum distance was observed between the cultivars Das 4 Estações and Suki, the minimal distance occurred between 'Chato de Quintal' and 'Astrus Plus'. The number of nymphs is the variable that allows the highest differentiation between cultivars. There is variability between cabbage commercial cultivars as to aphid feeding preference.

Opening the Treasure Chest: The Current Status of Research on Brassica oleracea and B. rapa Vegetables From ex situ Germplasm Collections

“…A screen of 27 cabbage (B. oleracea var. capitata) cultivars revealed a range of preference of cabbage aphid toward the tested accessions (de Melo et al, 2013). Plant resistance tests of eight genotypes of collard greens (B. oleraceae var.…”

Cabbage: Breeding and Genomics

“…This included sources of resistance and lines having resistance/tolerance to diseases viz., black rot, sclerotinia rot, downy mildew and Atlernaria leaf spot and important pests like diamondback moth and cabbage butterfly. A screen of 27 cabbage cultivars revealed a range of preferences of cabbage aphid toward the tested accessions (De Melo et al, 2013). 'Chato de Quintal', 'Ryuho', and 'Taishita' were the less preferred cultivars by the aphid.…”