Artrópodes fitófagos e predadores associados em 20 acessos Luffa sp. em sistema orgânico

Abstract

Resumo -Os objetivos desta pesquisa foram verificar os artrópodes fitófagos e seus predadores em 20 acessos de bucha vegetal Luffa sp. (Cucurbitaceae), a distribuição destes no dossel das plantas em cultivo orgânico e a produção de frutos dos acessos. O experimento foi em blocos casualizados com 20 tratamentos e quatro repetições. Os tratamentos foram os acessos P159, P304, P466, P03, P570, P569, P467, P30, P446, P495, P125, P263, P644 e P32, provenientes da Embrapa (CENARGEN, DF), e P01, P02, P04, P05, P06 e P07, obtidos em Porteirinha-MG. As parcelas foram compostas por quatro plantas de Luffa sp. A maior abundância de Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) foi observada nas folhas do acesso P467 em referência aos demais acessos de Luffa sp. Trigona spinipes (Fabricius) (Hymenoptera: Apidae) foi mais observada nas flores dos acessos P01, P03, P30, P32, P263 e P569 e menos abundantes nos acessos P05, P125, P159, P304, P446 e P570. Os acessos de Luffa sp. com maior número de frutos/planta foram P01, P03, P05, P06, P07, P30, P32, P125, P263, P446 e P570. Os predadores aranhas e Coccinellidae (Coleoptera) bem como o fitófago Cicadellidae (Hemiptera) preferiram atacar a face adaxial, sendo que não se detectou diferença estatística entre as faces para os demais artrópodes. T. spinipes esteve mais presente na parte apical do dossel das plantas. Com esses resultados, o acesso P06 é o mais indicado para o cultivo, pois foi um dos que apresentou maiores produtividades e menores taxas de ataque de insetos. Palavras-chave -Bucha vegetal. Inseto. Inimigos naturais.Abstract -The objectives of this research were to verify the phytophagous arthropods and their predators in 20 accesses of vegetable loofah Luffa sp. (Cucurbitaceae), the distribution of the canopy of the plants in organic system and the production of fruits of the accesses. The experiment was in randomized blocks designed with 20 treatments and four replicates. The treatments were the accesses P159, P304, P466, P03, P570, P569, P467, P30, P446, P495, P125, P263, P644 and P32, from Embrapa (CENARGEN, DF, Brazil) and P01, P02, P04, P05, P06 and P07, obtained in Porteirinha, MG, Brazil. Each plot consisted of four plants Luffa sp. The greatest abundance of Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) was observed in leaves of the access P467 in reference to the others accessions of Luffa sp.. Trigona spinipes (Fabricius) (Hymenoptera: Apidae) was observed in most flowers of accesses P01, P03, P30, P32, P263 and P569 and less abundant in accesses P05, P125, P159, P304, P446 and P570. The accesses of Luffa sp. highest number of fruits per plant were P01, P03, P05, P06, P07, P30, P32, P125, P263, P446 and P570. The spiders and predatory Coccinellidae (Coleoptera) and the phytophagous Cicadellidae (Hemiptera) preferred to attack the adaxial side, but no statistical difference was detected between the faces to the other arthropods. T. spinipes was present in the apical part of the plant canopy. With these results, access P06 is the most sui...

Dormancy breaking in seeds of different accessions of Luffa cylindrica Roemer

“…Luffa cylindrica Roemer, popularly known as loofah, Cucurbitaceae family, is a subtropical, annual, herbaceous plant that is abundant in China, Japan and other Asian countries, as well as in countries of Central and South America (Braga, 1979). This species is usually grown in small areas and mostly by small farmers (Leite et al, 2011). Since its market value is high and has remained stable for the last years, the cultivated area has expanded in several regions of Brazil and the demand for information on its cultivation has increased.…”