EVALUATION OF NON PATHOGENIC STRAINS OF FUSARIUM SPP. FOR THE MANAGEMENT OF CHRYSANTHEMUM (Dendranthema grandiflora Tzvelev.) WILT CAUSED BY Fusarium oxysporum f. sp. chrysanthemi
Loading...
Date
2019-12-28
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
UNIVERSITY OF AGRICULTURAL SCIENCES GKVK, BENGALURU
Abstract
A study was carried out to evaluate the non pathogenic strains of Fusarium spp.
for the management of Fusarium wilt of Chrysanthemum. Out of 67 Fusarium cultures
isolated from rhizosphere soil of Chrysanthemum fields, five Fusarium isolates proved
to be non pathogenic to Chrysanthemum and other non host crops. Morphological,
cultural and molecular characterization of non pathogenic Fusarium cultures was
performed and among five isolates, two were identified as Fusarium chlamydosporum,
two as Fusarium oxysporum and one was Fusarium solani. Antagonistic inhibition in
growth of the wilt pathogen was showed by non pathogenic Fusarium cultures UASB
NPF-I, UASB NPF-II and UASB NPF-III under in vitro dual culture study. The culture
filtrate extracts and volatile compounds of non pathogenic cultures showed substantial
results on inhibition of pathogen in vitro. Increased levels of total protein, phenols and
defense enzymes such as peroxidase, polyphenol oxidase, phenylalanine ammonia
lyase, β-1,3-glucanase and chitinase were observed in the plants treated with non
pathogenic Fusarium cultures. Higher levels of defense enzymes got induced in the
plants inoculated with non pathogenic Fusarium isolates followed by challenged
inoculation of pathogen. All the non pathogenic Fusarium cultures were positive for
phosphate solubilization and production of IAA and GA. Under greenhouse conditions
significant increase in plant growth parameters, reduced wilt disease incidence and
better root colonization by non pathogenic Fusarium cultures was observed. The
treatments which received non pathogenic Fusarium + pathogenic Fusarium showed a
slight increase in the plant growth parameters compared to inoculation of non
pathogenic Fusarium isolates alone. The isolate UASB NPF-III performed better than
other isolates throughout the studies.