Characterization of Native Fluorescent Pseudomonads against Sclerotinia Blight of Brinjal (Solanum melongena L.)

Abstract

Brinjal (Solanum melongena L.) is one of the most common and known rich source of vitamin B1 (Thiamin), dietary fibre, manganese, niacin (vitamin B3), copper, vitamin B6 (pyridoxine), folate (vitamin B9), potassium, Vitamin K. Brinjal cultivation is affected by several pests and diseases. Sclerotinia blight is one of the most destructive diseases of brinjal caused by Sclerotinia sclerotiorum (Lib) de Bary. Under the present investigation two isolates of Fluorescent Pseudomonads (FLPs) viz., FLP-Brinjal 2020-1 and FLP-Brinjal 2020-2, were evaluated against Sclerotinia sclerotiorum (SCL)under in vivo and in vitro conditions using dual culture, inverted plate assay. FLP-Brinjal 2020-2 gave maximum inhibition over the control followed by FLP-Brinjal 2020-1 against the pathogen in in vitro condition. Experiments conducted in pluck trays indicated that FLP-Brinjal 2020-2 was superior with least sclerotinia blight incidence (20.53%).The identity and diversity among the FLP isolates were examined by sequence analysis of 16s rRNA gene. The gene was amplified by PCR using primers pair, 27 F/1492 R. Amplified DNA products were sequenced and analysed by BLAST (BLASTn) programme at NCBI database for species identification. Among the 10 FLPs isolates assessed 9 were found to have maximum similarity with Pseudomonas aeruginosa. FLP 2020-2 and FLP 2020-1 were found to be Pseudomonas fluorescence which is in confirmation with the morphological observations. Significant diversity among the isolates was observed when dendrogram of the sequence was plotted using    CLUSTAL W.