FIELD EVALUATION OF PROMISING BACTERIAL ANTAGONIST BACILLUS SPP. AGAINST MELOIDOGYNE INCOGNITA IN GERBERA GERBERA JAMESONII

Abstract

ABSTRACT The present research deals with the study of antagonistic effect of Bacillus spp. against Meloidogyne incognita infesting Gerbera jamesonii. Two bacterial strains of Bacillus Subtilis were isolated from rhizosphere region of gerbera and the antagonistic potential against nematodes was observed by hatching and mortality studies. Field studies were conducted to assess the bioefficacy of liquid and talc formulations of Bacillus spp. viz., B. subtilis strain BG42, BG37 and B. amyloliquefaciens strain B4. Application of these three strains at 1%/m2 significantly increased the gerbera growth and quality parameters and decreased the nematode population compared to control. Among the treatments, Soil drenching of liquid formulation of B. subtilis strain BG42 gave maximum reduction of juveniles per 250g soil (71.92%), number of adult females/5g root (66.68%), number of eggmasses/ 5g root (76.35%), gall index (1.50) and increased flower yield/m2 (129.89%). Soil drenching of liquid formulation of B. subtilis strain BG37 was next line in efficacy. Further liquid formulation of B. subtilis strain BG42 had a positive influence on gerbera quality parameters viz., flower diameter (9.77 cm), colour of the flower, length of flower stalk (58.48 cm) and vase life (11.17 days). This study suggests that B. subtilis might be potential biological control agents of gerbera plants.