G. Sangeetha ¹, S. Usharani ¹

Affiliations
1 Department of Plant Pathology, Annamalai University, Annamalainagar, 608 002, Chidambaram, Tamil Nadu, IN

Abstract

Crown rot disease caused by Lasiodiplodia theobromae (Pat.) Griffon and Maubl. and Colletotrichum musae (Berk and Curtis) Arx. is the major problem in banana cv. Robusta. Efficacy of application time of biocontrol agents in postharvest environment in relation to pathogen infection is an important factor in controlling the crown rot disease of banana. Trichoderma viride isolates TV3 and TV4 which showed effectiveness against both pathogens in vitro were applied at different time intervals in relation to the time of pathogen inoculation in order to know the effective application time of biocontrol agents. Biocontrol agents were applied 2 and 4 h before pathogen inoculation; simultaneous challenge inoculation; and 2, 4 h after pathogen inoculation. The results indicated that the highest reduction of crown rot disease of banana was achieved when the biocontrol agents were applied 4 and 2 h before pathogen inoculation (preventive method of application) compared with the other treatments.

Keywords

Banana Crown Rot, Trichoderma viride, Time of Application.

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S. Usharani ¹, D. John Christopher ¹, A. Sujaritha ¹

Affiliations
1 Department of Plant Pathology, Annamalai University, Annamalainagar 608002, Chidambaram, Tamil Nadu, IN

Abstract

Pot experiments conducted to evaluate different delivery systems for Pseudomonas fluorescens in the management of fusarial wilt of tomato revealed that FYM enriched with P. fluorescens as seed and soil application was very effective in minimizing wilt incidence to 15.53 per cent. Carbendazim at 0.1% recorded 18.56% disease incidence and the untreated control recorded the maximum disease incidence of 38.25%. Significantly highest population of P. fluorescens was recorded when FYM enriched with P. fluorescens was used for seed treatment and soil application (30 × 10⁷ CFUs g^-1) on 60 days after sowing and the same treatment recorded the lowest population of Fusarium oxysporum f. sp. lycopersici (8.9 × 10² CFUs g^-1 of soil).

Keywords

Delivery Systems, Fusarium oxysporum f. Sp. Lycopersici, Management, Pseudomonas fluorescens, Survival, Tomato and Wilt.

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S. Usharani ¹, D. Johnchristopher ¹, R. Udhaya Kumar ¹, S. Sanjai Gandhi ¹, K. Pratheema ¹

Affiliations
1 Dept of Plant Pathology, Annamalai University, Annamalai Nagar 608002, Chidambaram, Tamil Nadu, IN

Abstract

Induced systemic resistance (ISR) in blackgram using organic amendments and biocontrol agents against Macrophomina phaseolina was studied under pot culture conditions. Soil application of FYM 12t ha^-1 combined with seed treatment (4g kg^-1) and soil application (5kg ha^-1 on 30 DAS) of T. viride significantly increased defense related proteins, viz., peroxidase (14.34 units min^-1 g^-1) and polyphenoloxidase (3.96 units min^-1 g^-1) activities as a sign of systemic resistance coupled with reduction in ischolar_main rot incidence from 99.6 to 13.8 per cent and also increased the yield and yield attributes of blackgram.

Keywords

Black Gram, Defense Related Proteins, Macrophomina phaseolina, Trichoderma viride.

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