| dc.description.abstract | In field and greenhouse experiments , 6 potato cultivars, namely, Annet, B 53; Kenya Baraka, Desiree, Roslin Tana Gild Roslin Gucha were tested for resistance to Meloidogyne javanica and M.incognita. The results demonstrated that the 6r s did nu t cultivars did not differ significantly in their susceptibility to the 2 root-knot nematodes. All of them were highly susceptible to the 2 root-knot nematodes. Studies of the development of M. javanica and M. incognita revealed that the 2nrl, 3rd and 4th moults occurred on the 22nd, 24th and 26th days, respectively, after inoculation. Egg-laying females were noted on 32nd day after inoculation and recovery of 2nd generation larvae of both species occurred on the 57th day after inoculation , The larvae of M. javanica and M. incognita penetrated the roots of Annet B 53, Kenya Baraka and Desiree potato cultivars when in inoculum of 200 larvae per plant was used, but the number of larvae in the roots of these cultivars did not differ significantly at exposure periods of 24 and ~8 hours after inoculation. The resu1ts 0f experiment with c1ay, loam an d sandy soils on larval penetration of N. javanica and M. Incognita int the roots of Annet, B53, Kenya Barakaa and Desiree revealed that the larvae of both nematode species penetrated into the Tor is of all the cultivar which were grown in the 3 soil typeH, but the number In the histopathological studies, results demonstrated that javanica and incognita caused L~tense damage to cortical and vascular tissue of roots of Annet, B 53, Kenya Baraka end Desiree potato cultivars. The 4 cultivars were very susceptible to both nematode species which fed in the vascular area and induced the formation of multinucleate giant cells around the nematode head. No nuclear division was observed in the giant cells in any of the root-sections of the 4 potato cultivars. | en |
