Tomato (Lycopersicon esculentum) is one of the widely grown vegetables worldwide. Fusarium oxysporum f. sp. lycopersici (FOL) is the significant contributory pathogen of tomato vascular wilt. The initial symptoms of the disease appear in the lower leaves gradually, trail by wilting of the plants. It has been reported that FOL penetrates the tomato plant, colonizing and leaving the vascular tissue dark brown, and this discoloration extends to the apex, leading to the plants wilting, collapsing and dying. Therefore, it has been widely accepted that wilting caused by this fungus is the result of a combination of various physiological activities, including the accumulation of fungal mycelia in and around xylem, mycotoxin production, inactivation of host defense, and the production of tyloses; however, wilting symptoms are variable. Therefore, the selection of molecular markers may be a more effective means of screening tomato races. Several studies on the detection of FOL have been carried out and have suggested the potency of the technique for diagnosing FOL. This review focuses on biology and variability of FOL, understanding and presenting a holistic picture of the vascular wilt disease of tomato in relation to disease model, biology, virulence. We conclude that genomic and proteomic approachesare greater tools for identification of informative candidates involved in pathogenicity, which can be considered as one of the approaches in managing the disease.

The present investigation was carried out during the year 2017-18 and 2018-19 in Laboratory of Microbiology, Devision of crop production, ICAR-National Research Centre for Seed spices Ajmer, Rajasthan (India). The maximum P solubilization zone was 19 mm followed by 17 mm recorded in isolate DCU-251 which was characterized as Pseudomonas aeruginosa (Accession no. MN192165) and DCU-262 (Kosakonia oryzendophytica strain NRCSSDCU262 Accession no. MN192166), respectively. The least solubilization zone was 11 mm due to isolate DCU-551. Phosphate solubilization index ranged 1.6-3.1. Highest SI was 3.1 followed by 2.9 and 2.8 associated with isolate DCU-251(Pseudomonas aeruginosa strain NRCSSDCU251 Accession no. MN192165), DCU-262 (Kosakonia oryzendophytica strain NRCSSDCU262 Accession no. MN192166) and DCU-22 (Bacillus paramycoides strain NRCSSDCU22 Accession no. MN192162), respectively. The Lowest value of SI was 1.5 due to isolate DCU-551. The highest soluble P (326 g ml −1 ) in pikovskaya's broth was recorded in bacterial isolate DCU-251(Pseudomonas aeruginosa strain NRCSSDCU251 Accession no. MN192165) and least soluble P was 152 g ml −1 recorded in isolate DCU-553.

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Background: Sclerotinia sclerotiorum (Lib.) de Barry is a soil-borne plant pathogen, capable of infecting more than 500 host plants worldwide. It is a major pathogen that plays a crucial role in reducing the yield of economically important crops. Sclerotinia rot also known as Stem rot or white mold, caused by Sclerotinia sclerotiorum is a serious disease of chickpea. Methods: The antagonistic potential of four bioagents i.e. Trichoderma harzianum (Th-BKN), Trichoderma viride (Tv-BKN), Pseudomonas fluorescens (Pf-BKN) and Bacillus subtilis (Bs- BKN) were isolated from chickpea rhizospheric soil. The fungal bioagents were tested for their antagonistic potential against the pathogen in vitro by modified dual culture technique on potato dextrose agar (PDA) medium. While bacterial antagonists tested for their antagonistic potential against the pathogen in vitro by paper disc inoculation technique on Nutrient Agar (NA) and Pseudomonas Agar Fluorescens (PAF) media. Each treatment was replicated four times, incubated at 23±10°C, data on the antagonistic activity of different bioagents were recorded and percent inhibition was calculated for each antagonist. Result: The fungal antagonists T. harzianum (Th-BKN) resulted in maximum growth inhibition of the pathogen (70.48%) and bacterial antagonists, Pseudomonas fluorescens (Pf-BKN) (37.56%) was more effective than the Bacillus subtilis (Bs- BKN).