Biocontrol of “Bacterial Seedling Rot and Grain Rot of Rice”

1. Biocontrol of “Bacterial Seedling Rot and Grain Rot of Rice” Causal Agent: Burkholderia glumae

2. Introduction:Problem to be addressed • To identify antibacterial activity of organic and aqueous extracts from Skeletonemacostatum(Diatom)against Burkholderia glumae, which is a causal Agent of “Bacterial Seedling Rot and Grain Rot of Rice” in the in vitro conditions. • One of the most destructive diseases of rice.

3. The Causal agent: Burkholderia Glumae • A gram-negative soil bacteria. • Formerly named Pseudomonas glumae. • Causal agent of grain rot and seedling rot of rice. • Burkholderia glumae produces Toxoflavin, which is toxic for plant. • This Toxoflavin generate superoxide & peroxide, which causes, Bacterial Seedling Rot and Grain Rot of Rice.

4. Symptoms of Disease • Infection is symptomized by brown, water-soaked soft rot of the rice. • Wilting or soft rot of the leaves sheath. • Spikelet sterility with poor or no grain ripening. • Leads to the death of the plant.

5. Biological Treatment & its Necessity • Use of chemicals & antimicrobial agents in paddy field may harm the normal soil flora. • Toxic for human health. • Thus, a biological treatment for the pathogen applied in the paddy field, can be worthy & harmless.

6. Treatment • Skeletonemacostatum (Bacillariophyceae) a marine, filamentous, planktonic diatom, common in Indian coastal water, produces Quinolone like compounds. • Thus an attempt has been made to use Skeletonemacostatumfor the inhibition of the bacteria of interest.

7. The Objective • Use of Skeletonemacostatum as an antagonist for the bacteria of interest. • The aim is to find new biological agents for control of the disease, remaining plant unaffected.

8. Experiment • Isolation of the bacteria from plant- A selective medium - CCNT • 2 g of yeast extract • 1 g of polypepton • 4 g of inositol • 10 mg of cetrimide • 10 mg of chloramphenicol • 1 mg of novobiocin • 100 mg of chlorotharonil • 18 g of agar in 1 liter of distilled water (adjusted to pH 4.8 )

9. Incubation of B. glumae. • Formation of yellowish white colony with a diffusible yellow pigment. • Other microorganisms were detected at a much lower rate on the CCNT medium. • For organic and aqueous extracts of Skeletonemacostatum – MASM (Modified Artificial Seawater Medium) along with Acetone and methanol in distilled water is used.

10. Agar Ditch Method • The isolated & screened Burkholderiaglumaefrom CCNT medium is sub-cultured on agar media • Incubation • A ditch was made in the plate with the help of a sterile cup-borer (0.85 cm)

11. The organic and aqueous extracts of Skeletonemacostatumwere introduced aseptically and the petri-plates were incubated at 270C (+10C) for 3-4 days. • Determination of the Antibacterial activity and microbial growth.

12. Observation and Result • Test organism inhibition zone- 15.0mm (+ 3.21). • This shows a high antibacterial activity of Skeletonema costatum against Burkholderia glumae.

13. Conclusion • Conditions which would enhance the antibacterial agent production from algae should be studied for the biological control of the Seedling Rot and Grain Rot of Rice due to Burkholderiaglumae. • To make it practicable in natural conditions of crop growth.

14. Applications and future prospects • This in vitro studied can be applied with some modification to prevent the diseases in paddy fields. • Development of the transgenic plants with improved qualities. • For designing novel compounds for agriculture. • Can be long lasting, inexpensive and harmless to the life. • Biocontrol systems eliminate neither pathogen nor diseases but bring them into natural balance.

15. Thankyou!!!