Attachment of six populations of P. penetrans spores on the second stage juveniles of two population of root-knot nematodes.

Abstract

The attachment studies on the second stage juveniles of rot-knot nematodes were carried out using six populations of hyperparasite (Pasteuria penetrans). The double blend population performed very significantly higher than the all other populations and Malakisi population of P. penetrans remained at second. However, greater numbers of spores attached to juveniles of Hypericum than the Navaisha population of nematodes. There was a significant (P<0.05) difference between all populations either in the number of spores per juvenile or percentage of spore encumbered juveniles. The attachment level of double blend remained same between 6 to 24 hours. However, the Malakisi population has shown that attachment level was continuously increasing until the last time of assessment time period of 24 hours (figure 3 a-b). In (figure 2 a – b) both populations of P. penetrans have shown very low attachment and there was no any significant increase in either the percentage of encumbered juveniles or in the total number of spores per juvenile. There was attachment comparison between six populations of Pasteuria (Malakisi, Thika, G11, H22, blend and double blend) with two populations of root-knot nematodes (Hypericum and Navaisha). All populations of spores were added to freshly hatched juveniles of the Hypericum and Navaisha populations in order to avoid any differences in their vigour and condition of the nematodes.