Blast of rice

This include introduction, symptoms, pathogen, life cycle and management of blast of rice.

1. BLAST OF RICE

DR. RAJBIR SINGH
Assistant Professor
Department of Plant Pathology
Gochar Mahavidyalaya, Rampur Maniharan, Saharanpur (UP), India
Affiliated to Ch. Charan Singh University, Meerut (UP), India

Email: [email protected], [email protected]
Cell No. 91-9456613374

2. BLAST OF RICE
•1704 - Seen in Japan
•1913 – Tanjavur by Butler
•Loss – 75%
•Symptoms:
•All parts except root infected
•Appeared in Nursery
•Boat Shaped water soaked
spots of > 0.5 mm long

3. •Corner of spot – dark brown red
•Middle – white grey / ash color
•Spots enlarge & collapse – leaf blightning
•Neck Infection / Neck Rot Phase (most dangerous)
•Black grey mycelium on the neck
•No grain formation/ partial formation

13. Pathogen – Pyricularia oryzae
P. grisea (Imperfect stage)
Magnaporthe grisea (Perfect stage)
•Survive in seed & plant residues
•Mycelium survive in puwal – 1-2 years
•Survive on weeds – Penicum repens, Digitaria marginata
•R. H. – 90%
•Tem. – 20-25° C

14. Systemic Position
Kingdom – Mycota/ Fungi
Division – Eumycota
Sub division – Deuteromycotina
Class – Hypomycetes
Order – Hypomycetales
Family – Dematiaceae
Genus – Pyricularia
Species - grisea

15. Conidia of Pyricularia gresia

16. •Reproductive structures -
(1). Conidia – Pear shaped with 2 septa
(2). Chlamydospore
(3). Sclerotium
•Toxin -
(1). Pyricularin
(2). ά– Picolinic acid
•Enzyme - (1). Pectinolytic enzyme

17. Disease cycle

18. Disease Management
•Use healthy seed
•Seed treatment – Tricyclazole or Beam 75 WP - @ 4 gm/ kg seed
•Removal of weeds
•Use balance fertilizers – no heavy use of N2
•Spray - (i). Beam @ 6 gm/litre or
(ii). Bavistin – 0.1 %
First spray - tillering stage
IIend spray – flowering stage
(iii). Contaf – 0.2 %
•Dis. Res. Var. - IR- 64, Pant Dhan-16, Pant Dhan Sankar - 1

19. Thank You