Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Plant-parasitic nematodes in field crops in South Africa. 6. Soybean.

Abstract

Twelve plant parasitic nematode genera and 25 species were identified in soil and root samples collected from 17 localities in the soyabean production areas of South Africa during the 1995/96 season. Predominant endoparasites found included Meloidogyne incognita, Meloidogyne javanica, Meloidogyne hapla, Meloidogyne ethiopica, Pratylenchus zeae and Pratylenchus brachyurus. Meloidogyne species occurred in 91% of all root samples, Pratylenchus zeae in 87% and Pratylenchus brachyurus in 33%. The occurrence of the three predominant endoparasites was not restricted to sandy soil, but they were also prevalent in soils with high clay contents. Other endoparasitic nematode species were Pratylenchus crenatus, Pratylenchus teres, Pratylenchus neglectus, Pratylenchus thornei, Rotylenchulus parvus and Ditylenchus africanus. Nematodes found in soil included Helicotylenchus dihystera and Scutellonema brachyurus [S. brachyurum], which occurred in 78 and 71%, respectively, of all soil samples. Other nematodes found in soil samples were H. pseudorobustus, H. digonicus, H. microcephalus, Scutellonema truncatum, Rotylenchus unisexus, Mesocriconema sphaerocephalum, Paratrichodorus minor, Longidorus pisi, Xiphinema vanderlindei, X. elongatum and Tylenchorhynchus goffarti. Highest prominence values for Meloidogyne species were recorded on cultivars Prima, Bakgat, Tamboti, Hutcheson and Knap and the lowest on cultivars PAN812, SCS1, Nyala, Gazelle and A7119. Eight nematode genera and 19 species extracted during this study are reported for the first time in association with soyabean in South Africa.