Induction of plant defense enzymes against crown rot disease of Arachis hypogaea L. by integrated disease management Presented by K.S.BALU II-M.Sc. (AMB) K.S.R CAS Guided by Dr. C. S. SUMATHI DEPT OF MICROBIOLOGY K.S.R CAS

INTRODUCTION Groundnut ( Arachis hypogaea L.) crop is extensively cultivated in the state of India and it is an important crop among major oilseed crops. Crown rot or collar rot caused by Aspergillus niger in groundnut leads to “patchy” crop stand and reduce the yields. Pseudomonas fluorescens are colonizing bacterial biocontrol strain that suppress phytopathogenic fungi. Also Polianthes tuberosa rhizome extract used to control of A.niger.

OBJECTIVES To analyse that the P.fluorescens induce the immune mechanism of plants to produce significant levels of plant defense enzymes against crown rot disease on ground nut. To analyse variations in the quantities of phytochemical compounds in groundnut plant. To identify effective combination of treatment to control crown rot disease under nursery trials. To provide an effective biocontrol method to treat crown rot disease by eco-benign approach.

MATERIALS AND METHODS Isolation of Pathogen: Pathogen : A. niger Source: Crown rot diseased ground nut (A. hypogea L.) Medium : Potato Dextrose Agar

Biocontrol agent :P.fluorescens Microbial agent : P. fluorescens .

Biological materials used to control the growth of A.niger A. sativum P. tuberosa Castor oil

Methods: Invitro Study – Dual Plate Culture Antifungal (A. niger) activity of P. fluorescens, Garlic extract, P. tuberosa extract, castor oil are tested by dual culture method in Potato Dextrose agar medium. All the plates are incubated at 30°C for 6 days, after incubation antagonistic activity is determined by method of Watanabe (1984).

NURSERY EXPERIMENTAL STUDY The bag media prepared by mix FYM, soil and sand in the polythene bags filled with 1 kg /bag in the ratio of 1:1:1. The selected groundnut seeds (VRI2) is selected and inoculated. After 15 days, plants treated with A. niger and later with P. fluorescens, P.tuberosa root extract, Garlic extract and castor oil with following combination;

Contd., T4-A.niger+Castor oil T1-Control T2-A.niger T3-A.niger+P.fluorescens T4-A.niger+Castor oil T5-A.niger + Garlic extract + P. fluorescens. T6-A.niger + P.tuberosa plant root extract

Invivo nursery experimental study : T1 T2 T3 T4 T5 T6

RESULT :Microscopic view of Aspergillus niger

Invitro study-Antagonistic activity of P. fluorescens against A. niger Zone formation P. fluorescens inhibits A . niger Control

WORK TO BE DONE Measurement of Plant Growth and Yield: Plant growth parameters –leaves, shoot height, root length, shoot and root biomass will be measured.

MEASUREMENT OF PHYTO CHEMICAL COMPOUNDS Total protein –Lowery et al., method. Total phenol –Singleton &Rossi assay. Total carbohydrate-Anthrone method.

MEASUREMENT OF PLANT DEFENSE ENZYMES Superoxide dismutase assay. Polyphenol oxidase assay. Peroxidase assay.

Expected Outcome The integrated disease management will be effective to control crown rot of ground nut when compared to chemical treatment.

REFERENCES Chohan .J.S, Journal of Research,1973,(6):634-640. Anand. R. and Kulothungan. S, Annals of Biologiocal research,2014,5 (9):1-9. Strouble, M. Phytopathology,1955,45,419-420. Harsukh Gajera et al Journal of Plant Protection Research,2011,51,(3):240-247. Malik CP and Singh MB. Plant enzymology and histo enzymology,1980,286. Lowry et al., Journal of Biochemistry,1951,193,265-275. Beauchamp C, Fridovich I, Analytical Biochemistry,1971,44,(1):276-287.

Contd., Bobbarala , V., Katikala, P.K., Naidu, K.C and Penumajji, S. Indian Journal of Science and Technology,2009,2(1) : 87-90. Mahesh, B., and Satish, S. World Journal of Agricultural Sciences,2008,4 :839-843. Shubhi Avasthi., Ajay K. Gautam and Rekha Bhadauria. Biological Forum,2010,2(1) : 53-55.

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