blast of rice
TRANSCRIPT
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
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
• 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
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
Systemic Position
Kingdom – Mycota/ Fungi
Division – Eumycota
Sub division – Deuteromycotina
Class – Hypomycetes
Order – Hypomycetales
Family – Dematiaceae
Genus – Pyricularia
Species - grisea
Conidia of Pyricularia gresia
• Reproductive structures -
(1). Conidia – Pear shaped with 2 septa
(2). Chlamydospore
(3). Sclerotium
• Toxin -
(1). Pyricularin
(2). ά– Picolinic acid
• Enzyme - (1). Pectinolytic enzyme
Disease cycle
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
Thank You