Phytonematode on Pineapple (Ananas comosus L. Merrill) GP3 Clone With Symptoms of Pineapple mealybug wilt-associated virus (PMWaV)

Abstract

Pineapple (Ananas comosus L. Merr) is one of Indonesia’s important fruit commodities. Indonesia became the world’s fourth-largest pineapple producer in 2020. The monoculture cultivation system can lead to the continuous presence of pests and diseases in plantation areas. Mealybug wilt disease is caused by Pineapple mealybug wilt-associated virus (PMWaV) and its thought to be associated with phytomatodes. This study aims to determine the type of phytomatodes in pineapple plants with three health degrees: healthy plants, moderate symptoms, and severe symptoms. The soil and roots were sampled at 3, 5, 13, and 14 MAP (Month after Planting). Nematodes were extracted from the soil using the flotation-centrifugation method, while the root samples were extracted using the mist chamber method. Identification of nematode morphology was based on anterior (mouth and stylet shape), posterior (tail shape and reproductive organs), and the type of annulation or nematode cuticle surface. Seven genera of phytomatodes were identified from soil and root samples: Pratylenchus spp., Rotylenchulus spp., Meloidogyne spp., Helicotylenchus spp., Crinonemoides spp., Tylenchus spp., and Rotylenchus spp.. The dominant phytonematodes in the soil samples were Rotylenchulus spp. (66.67/100 ml of soil), while Pratylenchus spp. predominated in the roots (58.33/10 g of roots). Based on the three degrees of plant health, the phytonematodes that dominated the soil samples were Rotylenchulus spp. on the health degree of healthy and moderate symptoms, and Meloidogyne spp. dominate the sample at severe symptoms. Pratylenchus spp. dominated the root samples at healthy and severe symptoms, while Rotylenchulus spp. predominate in moderate symptomatic samples.