Variability studies on Fusarium oxysporum f sp lycopersici causing wilt of tomato and competent effects of bio agents botanicals and their combinations

Abstract

Tomato (Lycopersicon esculentum) is one of the most significant vegetable crops recognised newlineas a protective food due to its unique nutritious content and widespread production. It is newlinecultivated in 4.5 million hectares with an output of 115.5 million metric tonnes globally. India newlineranked third internationally in terms of output and area with production of 333.25 metric tonnes newlinefrom an area of 27.56 million hectares. Several diseases limit the output of tomatoes leading to newline100 percent yield losses. Among all diseases, wilt caused by Fusarium oxysporum f. sp. newlinelycopersici (FOL) is the most destructing in both greenhouse and field environments. Hence, newlineto survey and observe the variability among the isolates of Fusarium oxysporum f. sp. newlinelycopersici from various locations of Bhilwara. Ssurvey showed that Bardod (36.17%) had the newlinehighest disease incidence whereas lowest disease incidence percent was recorded at Atoon newline(12.50%). All isolates procured had the similar type of characteristics as illustrated by previous newlineresearchers and showed variable degree of pathogenicity. They had also significant variationsin terms of morphological characters like radial growth, conidial measurements, mycelium newlinecolour, pattern of the mycelium and pigmentation of the isolate in the medium. In field trials, newlineProvax [carboxin + Thiram] at 2gm/litre was best effective for attaining the maximum height newline(76.95 cm), maximum number of branches (15.68), maximum number of leaves (97.61) and newlinemaximum yield (219.98 q/hec.) with maximum disease reduction (8.14%). In comparison to newlinechemical treatment bio-agent T. harzianum at 5% was also equally effective for maximum newlineheight (747.32 cm), maximum number of branches (15.19), maximum number of leaves newline(96.52) and maximum yield (214.09 q/hec.) with maximum disease reduction (10.45%). newlineKeywords: Tomato, Fusarium oxysporum f. sp. lycopersici, eco-friendly, variability, isolates, newlinebio-agents, botanicals. newline