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The present studies were undertaken to investigate the effect of various isolates of Pseudomonas fluorescens in Tamil Nadu against chilli anthracnose. A total of Six isolates of P. fluorescens were isolated from rhizosphere soil of Major chilli growing areas in various part of Tamil Nadu. All the collected isolates of P. fluorescens were identified and purified using streak method. All the isolated showed results in gram staining (negative), gelatin liquefaction (positive), catalase test (positive), oxidase test (positive), starch hydrolysis (negative) and fluorescent pigmentation (positive) IAA production (positive). Among the various isolates, Pf 1 produced more quantity of IAA and siderophores production. Also, Pf 1 produced maximum reduction of mycelial growth C. capsici under dual culture and poisoned food techniques.

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Organic formulations against rice sheath blight disease are gaining momentum and encompasses all available control methods with each method compensating the deficiencies of other disease management practices. Combined use of biological and seaweed extracts are an important effective against sheath blight disease caused by Rhizoctonia solani .Pot culture experiments were conducted with various organic formulation alone. The different organic formulations (viz., T 1 -Pseudomonas fluorescens( ST), T 2 -Sargassum wightii ( ST) , T 3 = T 1 + T 2 (ST) , T 4 -Sargassum wightii ( spray) , T 5 = Sargassum wightii+ Pseudomonas fluorescens ( spray) , T 6 =T 3 + T 5 , T 7 -control) were tested against sheath blight disease incidence and growth and yield attributes in rice under greenhouse condition . Among the treatments, (T 6 = T 3 +T 5 ) recorded the least sheath blight incidence and increase the bio metrics and yield characters. Rice plants treated with T 6 followed by challenge inoculation with R. solani gave a maximum induction of β-1, 3-glucanase activity on 5th day after pathogen inoculation and declined thereafter, maximum peroxidase activity at 7th day after pathogen inoculation then declined slowly, polyphenol oxidase activity on the 7 th day and thereafter declined. Maximum activity of phenylalanine ammonia lyase activity was observed on the 7 th day of inoculation.

A field experiment was conducted during Navarai season at Annamalai University Agricultural Experimental Farm using ADT 36 as test cultivar. The efficacy of potassium silicate (3%) was assessed by spraying it once, twice and thrice at different crop growth stages (15, 30 and 45 DAT-Days After Transplanting). The results indicated that the disease incidence was minimum in plots sprayed thrice with potassium silicate at 15, 30 and 45 DAT, followed by plots received two sprays at 15 DAT and 30 DAT which were statistically at par. The grain yield and straw yield were higher in plots sprayed thrice (15, 30 & 45 DAT) followed by plots receiving two sprays.