Morphological and Phylogenetic Characteristics of Ditylenchus dipsaci among Garlic Plants

Abstract

Stem and bulb nematode, Ditylenchus dipsaci (Kuhn, 1857), is a severe pest on garlic and other vegetables causing yellowing of leaves and rotting of bulbs. The existence of D. dipsaci in Indonesia was first reported in Temanggung, Central Java, in 2018. These researches aim to determine the distribution area, identification, and the genetic relationship of D. dipsaci which attacked garlic in Central and East Java. The study was conducted by sampling garlic plants attacked by D. dipsaci and extraction-isolation by immersion method. Species identification was carried out morphologically, morphometrically, and molecularly using PCR techniques. The results showed that D. dipsaci has been spread on garlic plants in Central Java (Magelang, Temanggung, Karanganyar, Tegal, and Brebes) and East Java (Malang and Mojokerto). The varieties that were attacked were Lumbu Kuning, Lumbu Hijau, Sangga Sembalun, and Tawangmangu Baru. The highest population was found in Kaliangkrik, Magelang, with 53.46 nematodes (5 g bulbs)-1. Based on morphological and morphometric identification, the species found was D. dipsaci. Based on molecular identification, samples from Jabung Mojokerto and Malang Poncokusumo were amplified at ± 600 bp with the D2A / D3B primers in the 28s rDNA region. D. dipsaci, found in East Java, was an indigenous Indonesian species based on phylogenetic studies.