Nematode reproduction and damage to Musa sword suckers and sword sucker derived plants

The susceptibility and sensitivity to Radopholus similis and Helicotylenchu s multicinctus of 2-month-old plants derived from sword suckers (early scre ening) and of sword suckers of established 18-month-old mats belonging to 1 2 Musa genotypes was investigated and compared. Differences in nematode pop ulation densities and root damage (number of functional roots, percentage o f dead roots and necrosis) were observed between the two evaluation trials which suggests a different host plant response to nematode attack of young root systems compared to older root systems. Therefore, for early screening , it is proposed that sword sucker derived plants be grown in nematode-free soil for at least 8-10 weeks to enable the plants to develop mature root s ystems, comparable to those of sword suckers from established mars.