Biological control of Meloidogyne incognita on tomato and banana with rhizobacteria actinomycetes, and Pasteuria penetrans

Glasshouse experiments were conducted to determine the efficacy of plant gr owth-promoting rhizobacteria, (Bacillus cereus, B. subtilis, B. sphaericus agrobacterium radiobacter, Pseudomonas fluorescens, P. chlororaphis and Bur kholderia cepacia), uncharacterized actinomycetes (strains 29 and 45), and the nematode-parasitic bacterium Pasteuria penetrans (isolate 100) against Meloidogyne incognita race 1 on tomato and banana. All bacteria and actinom ycetes enhanced the growth of both crops, and suppressed root-gall developm ent on tomato as compared to control plants. Root-gall indices oil tomato i noculated with M. incognita and bacteria ranged from 25 to 31% Versus 94% f or the nematode control. The bacteria also limited reproduction of M. incog nita on both tomato and banana with the reproduction factor (Rf) for M. inc ognita on barteria-treated tomato ranging from 9 to 24 versus 143 for the n ematode-untreated control. The Rf for M. incognita on both tomato and banan a ranged fi-om 9 to 38 where bacteria were added versus 80 without bacteria . Significant suppression of associated root necrosis was observed in all b acteria-treated tomato in one of two tests. The root-galling pattern on tom ato was radically different in all the rhizobacteria and actinomycetes-trea ted plants which showed minute round galls almost resembling M. hapla infec tion with a profuse root sytem.