Disinfection of cowpea (Vigna unguiculata) seeds on seedlings development

Abstract

The fast expansion of annual crops in recent decades with little phytosanitary management has led to the dissemination of several pathogens in the Brazilian cowpea-producing regions. Although, seed treatment is a common practice, there are no registered products for the cowpea and farmers apply the fungicides recommended for soybean cultivation. This study aimed to evaluate the influence of sodium hypochlorite and fungicidal treatments on the germination and initial development of seedlings of five cowpea cultivars under greenhouse conditions. Two experiments were established, one with seeds of five cultivars stored during 120 d, and another with newly collected seeds, disinfected or not with sodium hypochlorite, and treated with five fungicides. Emergence in sand, germination speed, and dry mass of seedlings were evaluated. Germination in sand, germination speed and dry mass of seedlings obtained from seeds of cowpea cultivars were negatively influenced by sodium hypochlorite disinfection. Fungicides used negatively influenced cowpea seed vigor for BRS Cauamé and BRS Novaera, even in the absence of sodium hypochlorite. Seed germination of five cowpea cultivars was not affected by the fungicides fludioxonil, carbendazim, carbendazim + thiram and carboxin + thiram.