Abstract

                                A field survey was conducted in 12 districts of Assam viz., Jorhat, Golaghat,Nagaon, Marigaon, Goalpara, Dibrugarh, Tinsukia, Lakhimpur, Dhemaji,Sivsagar, Kamrup and Barpeta. A total of 92 root samples were collectedand 37 bacterial isolates were isolated from commercial banana cultivars.The culture filtrates extracted from 37 endophytic bacterial isolates, werescreened against southern root-knot nematode, Meloidogyne incognita invitro and under pot culture studies. The five bacterial isolates viz., EB4, EB8,BC1, BC11 and BC12 showed 100% inhibition of egg hatching and juvenilemortality of M. incognita with an exposure period of 48 and 72h. On seedbacterization, with these five promising isolates, two isolates viz.EB4, BC1significantly enhanced germination percentage (33.33, 25.31%) and vigourindex (75.5, 64.39%) of paddy, receptively. The potential bacterial isolatesviz., BC1 and EB4 were identified as Lysinibacillus sp. and Pseudomonassp., respectively , based on the morphological phenotypic and biochemicalcharacterization. The pot culture experiment revealed that the bacterialendophytes viz., Lysinibacillus sp. (BC1) Pseudomonas sp. (EB4) significantlyreduced the soil (61.64, 56.71%) and root nematode population (77.29,68.87%), number of adult females (73.97, 69.89%), egg masses (85.63,80.11%) and root-knot index (1.33, 1.67) of M. incognita compared tountreated control. The bacterial endophytes viz., Pseudomonas sp. (EB4),Lysinibacillus sp. (BC1) were also significantly increased the growthparameters viz., shoot length (43.33, 39.18%), and root length (78.24,59.26%) and pesudostem girth (58.38, 52.13%)

Key words : Lysinibacillus sp; Pseudomonas sp.; Endophytes; antinemic property; Banana; Root-knot nematode and Growth promotion