000 03086nam a2200241Ia 4500
003 OSt
005 20230405152821.0
008 130502s9999 xx 000 0 und d
040 _cCPGS
082 _a632.96
100 _aKipgen, T.Lhingkhanthem
_9800
245 _aCharacterization of fluorescent pseudomonads and their evaluation against Ralstonia solanacearum(Smith) Yabuuchi under Meghalaya condition /
_cby T.Lhingkhanthem Kipgen
260 _aUmiam :
_bCPGS, CAU,
_cc2010
300 _a[24],80p.:
_bill.,some col.;
440 _a[Plant Pathology, School of Crop Protection]
_9801
520 _aUtilization of rhizospheric microbiota to induce plant growth and control of plant diseases is one of the important approaches to reduce environmental impact of hazardous chemicals. Fluorescent Pseudomonads are often predominant among plant rhizosphere associated bacteria. The rhizospheric fluorescent Pseudomonads of Meghalaya region have not yet been characterized and documented. The present investigation was focused on characterization of fluorescent Pseudomonads and their evaluation against Ralstonia solanacearum (Smith) Yabuuchi under Meghalaya condition. Soil samples were collected from rhizospheric regions of rice and maize crop from three districts viz., Ri-bhoi, East Khasi Hills and West Garo Hills districts of Meghalaya and 30 fluorescent Pseudo monads were isolated. On the basis of biochemical and cultural properties, 21 fluorescent Pseudomonads were identified as Pseudomonas jluorescens and tentatively designated as biovar I, II, III and V with 12, 7, 1 and 1 number of isolates respectively, whereas 3 isolates were identified as P. putida. The largest numbers of isolates were grouped in biovar I and most of these isolates were collected from rice rhizosphere. Hierarchical cluster analysis using Bray Curtis resemblance matrix on the basis of 16 biochemical tests of 21 Pseudomonas jluorescens, generated 3 distinct clusters at 96 per cent similarity level. Molecular characterization of 30 fluorescent Pseudomonads based on BOX Polymerase Chain Reaction (PCR) generated 12 amplification profile and the most prevalent profile was 'L' (9 isolates) with a band size of 750 bp, associated only with isolates of rice rhizosphere. Seven fluorescent Pseudo monads were screened on the basis of their HCN production and amplification by using pyrrolnitrin (PRNPrncf 5'CCACCAAGCCCGGCCAGGAGC-3' PRNPrncr 5'-GAGAAGAGCGGGTC GATGAAGCC-3') primer and tested for in vitro antagonism towards R. solanacearum, a wide spread, major bacterial pathogen of solanaceous crops. Isolate F.Pd19 was found most effective antagonist against R. solanacearum under in vitro condition with an inhibition zone of 4.03cm in diameter and may serve as promising bioagent, which need further in vivo investigation.
650 _aPlant disease-Biological control
_9802
650 _aPseudomonads
_9803
650 _aRalstonia solanacearum
_9804
700 _aMajumder, Dipali
_eMajor Advisor
_9805
856 _uhttps://krishikosh.egranth.ac.in/handle/1/5810196094
942 _2ddc
_cTH
999 _c3997
_d3997