Damage to Roots of Musa Cultivars by Radopholus similis with and without protection of Nematicides

Damage to root systems of five Musa cultivars caused by Radopholus similis was assessed over two crop cycles. In addition, a comparison was made of the response to two nematicide treatments made during the first cycle, 3 and 6 months after planting. The cultivars differed in their degree of susceptibility. Population levels of R. similis were higher on untreated susceptible cultivars than on treated ones. Nematode population densities did not differ among nematicide treatments for the resistant cultivar (Yangambi km5). Population levels from the untreated resistant cultivar were significantly lower than populations from treated susceptible cultivars. The root systems of susceptible Musa clones were severely damaged by R. similis. On the selected sucker for the second crop, 85% of the entire root system of susceptible cultivars was necrotic, compared to only 5% on the resistant Yangambi km5. The use of nematicide significantly increased the health (more functional roots, less corm dam