Enset (Ensete ventricosum) landraces associated parasitic nematodes and their relationship with Xanthomonas wilt disease in Gurage, Ethiopia

Enset production in Ethiopia is constrainted by nematode disease. This study has examined the type, abundance and distribution of plant parasitic nematodes (PPNs) and their relationship with Xanthomonas wilt of enset. Stratified random sampling technique was used to collect soil and root samples, and nematodes were extracted from the soil and fresh root samples. Eight nematode genera including. Pratylenchus, Meloidogyne, Helicotylenchus, Tylenchorhynchus, Meloidodera, Machroposthonia, Scutellonema and Xiphinema were recovered from the soil samples as well as Pratylenchus and Meloidogyne from the root samples. All roots and 87.7% of the soil samples possessed one or more nematode genus. Pratylenchus was the most abundant and frequently occurring nematode, accounting for 99.9% and 51.6 % of the total nematode density recovered from the root and soil samples, respectively. The studied enset landraces significantly differed in the nematode they harbored, of which Ageremremat, Shertye, Kibnar and Guarye were the top for Pratylenchu but was lowest on Lemat, Yiregiye, Beshute, Woka, Derewetye, Gufenwe, Charkma and Emirye landraces. Nematode density was significantly higher in samples collected from agro-ecologies at higher altitudes. Moroever, the density of Pratylenchus, Meloidogyne and Helicotylenchus, was remarkably higher on acidic compared with alkaline soils. Enset plants infected by Xanthomonas wilt showed significantly higher densities of Pratylenchus, Helicotylenchus and Tylenchorhynchus. This study provided additional evidence on the distribution and level of damage caused by nematodes on enset crops that is important to all the relevant stakeholders across the crop's value chain in designing and implementing feasible integrated pest management approaches.