Foot rot or bakanae disease of rice

Dr. Man Mohan Kumar
Krishi Rasayan Export Pvt Ltd New Delhi
A major disease of Rice in India

1. Foot Rot or Bakanae Disease of Rice Dr. Man Mohan Kumar Krishi Rasayan New Delhi

2. Presentation Overview

3. History Bakanae disease was first identified during 1828 in Japan. Shotaro Hori (1898) first time demonstrated the fungus Fusarium heterosporium n ees induced the bakanae symptom in rice plants. It was later put in the genus Gibberella under the name G. fujikuroi (Sawada) (Ito and Kimura, 1931). In India, the prevalence and incidence of bakanae disease has been reported particularly on basmati rice cultivars area like Uttar Pradesh, Haryana and Punjab. (Pavgi and Singh, 1964)

4. Economic Importance The yield losses ranging from 15-25% have been reported from Uttar Pradesh, Assam, Andhra Pradesh, Tamilnadu, Haryana and Punjab states of India. (Sunder et al., 2014). B akanae pathogen was also found to be associated in highest percentage (1-24%) in seeds of different basmati rice cultivars and showed the profound effect of the disease on seed quality (Butt et al., 2011).

5. Causal O rganisms Fusarium moniliforme (conidial stage) Gibberella fujikuroi (perfect stage) Domain: Eukaryota Kingdom: Fungi Phylum: Ascomycota Class: Sordariomycetes Order: Hypocreales Family: Nectriaceae Genus: Gibberella Species: Gibberella fujikuroi

6. Symptoms It is seed borne fungal disease. Seedling appear whitish pale and weaker Early infections can cause seedlings to die at early tillering stage. Infected seedlings have lesions on roots. In initially stage tips of seedling show symptoms of wilting. The fungus infects plants through roots or crowns. It spread through wind or water. Infected plants are abnormally tall thin with pale leaves and few tillers. Produce only partially filled or empty grains .

7. Disease C ycle The pathogen is also present in seed and soil or in plant material. There are two type of infection caused by bakanae disease Primary infection. Secondary infection. Th e i n f ection on seed or with i n so i l i s pr i ma r y infection. The infection on the infected plant is secondary.

8. Epidemiology Bakanae is a monocyclic disease. The fungus produces conidia on diseased plants, which are easily spread by wind and water. The fungus have a wide range of temperature between 27 – 35 c for optimum growth. Disease is further affected by high humidity and moisture leads to elongation of the culms. Higher levels of nitrogen and potassium affect the survival and population of fungus.

9. Management Use resistant variety. Use disease free seed for sowing . Store the grains with 12-14 % moisture content . Bagga and Sharma (2006) found seedling treatment with carbendazim or benlate (0.1%) for 6 and 8 h, significantly reduced the disease incidence up to 92 %. Propiconazole 25 EC at 0.05% was the most effective treatment in controlling foot-rot, but it showed signs of phytotoxicity along with reduction plant height and grain yield . (Source- Gupta at al. 2015) U se a fungicide that contains triflumizole, propiconazole, prochloraz. (Source- RIB) Seed treatment with (50 % carbendazim) was the most effective followed by (25 % Tebuconazole EC), ( 25% Propiconazole EC)and (2.5 % Fludioxonil and 2.5% Difenoconazole EC . (Source- BRRI ) ) Field trials indicate that a seed treatment with sodium hypochlorite @ 2.5% solution (Ultra Clorox Germicidal Bleach) is effective at reducing the incidence of this disease. (Source - UCIPM)