Yellow disease on pepper in Bangka, Indonesia: The symptoms, diversity and population of nematodes

Abstract

Meloidogyne incognita and Radopholus similis are the primary pathogens that reduce crop losses by up to 60% and cause yellow disease in pepper in Bangka. Consequently, the research aims to know the distribution diversity and population of nematodes, plant parasites, and non-parasites alike and the symptoms of the yellow disease on pepper. This study was carried out by selecting samples of pepper with symptoms of the yellow disease from a field on Bangka Island. Samples of soil and root were taken from three symptomatic plants in each site and repeated three times. Nematodes were extracted from samples and identified based on morphological characters. The results showed that the dominant symptoms of the yellow disease were yellowing of the leaves, stiff and curved towards the stem, small brownish spots and large blackish-brown spots on the leaf surface, yellowing, and severe symptoms until the leaves fall. The nematodes/ 100 ml of soil were Meloidogyne spp. with a total population of 275 individuals, Criconemoides sp. 158.33 individuals, Rhabditida group 1350 individuals, Aphelenchus avenae 25 individuals, and Mononchida group 25 individuals. The nematodes/ 5 g of roots were Meloidogyne spp. with a population of 775 individuals, Radopholus similis 133.33 individuals, and Criconemoides sp. 16.67 individuals.