Distribution of Citrus Nematode ( Tylenchulus semipenetrans Cobb, 1913) in Major Citrus (Citrus sinesis L.) Growing Areas of Ethiopia

Abstract

Citrus production in Ethiopia is threatened by a number of biotic and abiotic factors. Among these, citrus nematode (Tylenchulus semipenetrans) is one of the most important biotic constraints in the country. The objective of this study was to assess the incidence and distribution of ci tins nematodes in major citrus growing areas of Ethiopia. A survey was conducted in five major citrus growing provinces throughout the country. Ten genera of plant-parasitic nematodes were identified. Among all, the citrus nematode, Tylenchulus semipenetrans was predominant and was found in 95%, 90% and 20% of the orchards sampled from Hurso, Nura Era and Fetule, and Gota respectively. Other genera of plant-parasitic nematodes identified include Criconemella spp., Hemicriconemoides spp., Longidorus spp., Pratylenchus spp., Radopholus spp., Paratrichodorus spp., Paratylenchus spp., Tiichodorus spp., and Tylenchulus spp. This study documented that citrus orchards in Ethiopia are highly infected with plant parasitic nematodes and indicated sound nematode management practices are urgently needed.