COMPARISONS OF THE SPORE ATTACHMENT OF TWO POPULATIONS OF PASTEURIA PENETRANS (MALAKISI AND THIKA) ON TWO DIFFERENT POPULATIONS OF ROOT-KNOT NEMATODE KNOWN AS HYPERICUM AND NAVAISHA

In-vitro studies were conducted to point out most ignored points related to Pasteuria penetrans to achieve maximum number of spore and attachment to root-knot nematode isolates known as (Hypericum and Navaisha). The cuticles of root-knot nematodes have shown a high level of heterogeneity suggesting that this has an effect on the recognition and/or attachment process. Attachment levels of different Pasteuria populations developed from an original population of P. penetrans (the population known as Pp3) and a population that was developed from a single spore line of that original population are compared on a single egg mass line and a parent population of M. javanica. Pasteuria penetrans spore suspensions were prepared from previously soaked root powder containing endospores of P. penetrans (Malakisi and Thika). The attachment was compared between two populations of root-knot nematodes (Hypericum and Navaisha). Both types of spores were introduced to freshly hatched juveniles of the Hypericum and Navaisha populations so there should not be any differences in the vigour and condition of the nematodes. These attachment studies have proved that Malakisi population of P. penetrans has shown more significantly more number of spores attached to juveniles than Thika population. There was a significant (P<0.05) difference between both populations either in the number of spores per juvenile or percentage of spore encumbered juveniles. KEYWORDS: Root-knot nematodes (Hypericum and Navaisha), two populations of Pasteuria penetrans (Malakisi and Thika), attachment studies.