Detection and identification of Aphelenchoides fragariae nematodes on shallot bulbs in Bogor, West Java, Brebes Central Java, and Nganjuk, East Java

Abstract

Shallot is one of the most important horticultural commodities in Indonesia. Aphelenchoides fragariae is the major parasitic nematode of shallots and is listed as a quarantine pest with limited distribution. The nematode was detected on shallot bulbs at several traditional markets in Bogor but has not been reported present on shallot plantation. This research aims to detect and identify A. fragariae on shallot bulbs. Shallot bulbs were sampled from Bogor (West Java), Brebes (Central Java), and Nganjuk (East Java). Morphological identification was carried out by following the standard taxonomic for the Aphelenchoides genus (Aphelenchoididae). Morphometric indications were based on de Man’s formula. The result showed that A. fragariae was found on shallot bulbs from Bogor, Brebes, and Nganjuk. Female of A. fragariae has a slender body, and off-set lip characteristic distinguishes it from other nematodes. The stylet was invisible, but the metacorpus (median bulb) was visible and full rounded, Tail elongate conoid with a single mucro. Morphometric: female, n = 20, L = 312.2 – 550.5, a = 20.0 – 33.9, b = 7.0 – 12.0, c = 3.9 – 15.2, V = 34.4 – 84.4, T = 28.8 – 121.3, and stylet 6.8 - 12.0. Male, n = 20, L = 263.6 – 550.5, a = 21.1 – 37.8, b = 7.0 – 14.4, c = 8.4 – 17.1, T = 28.8 – 121.3, and stylet 7.6 -12.5.