BIOLOGICAL-CONTROL OF HETERODERA-CAJANI AND FUSARIUM-UDUM BY BACILLUS-SUBTILIS, BRADYRHIZOBIUM-JAPONICUM AND GLOMUS-FASCICULATUM ON PIGEONPEA

Bacillus subtilis, Bradyrhizobium japonicum and Glomus fasciculatum we re used alone and in combination for the management of a wilt disease complex of pigeonpea caused by the nematode Heterodera cajani and the fungus Fusarium udum. Application of all the three management agents a lone or in combination to plants inoculated with the pathogens increas ed shoot dry weight, number of nodules, phosphorus content, and reduce d nematode multiplication and wilting index. Application of B. subtili s alone to plants inoculated with either of the pathogens caused a sim ilar increase in shoot dry weight as to that caused by G. fasciculatum . However, use of B. subtilis on plants inoculated with both the patho gens resulted in greater shoot dry weight than caused by G. fasciculat um or B. japonicum. Increase in shoot dry weight was greater when plan ts inoculated with pathogens were treated with G. fasciculatum plus B. subtilis or these two combined with B. japonicum. Application of all the three management agents against pathogens resulted in the greatest nodulation and the greatest reduction in nematode multiplication. Com bined application of G. fasciculatum and B. japonicum increased root i nfection by G. fasciculatum while combined use with B. subtilis reduce d mycorrhizal colonisation.