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International Journal of Agricultural Science 

and Research (IJASR) 

ISSN(P): 2250-0057; ISSN(E) 2321-0087 

Vol. 3, Issue 5, Dec 2013, 13-16 

© TJPRC Pvt. Ltd. 



-Journal Publications ■ Research Consultancy 




Department of Plant Protection, SHIATS, Allahabad, Uttar Pradesh, India 


A typical symptom was observed during routine survey of Central Research field, SHIATS, Allahabad, as nearby 
villages in the kharif season-2012. The first symptoms were observed on leaves. The spots were brown in colour. The 
maximum infection was recorded leaf sheath as compared with leaves and kernels. Perusal of the literature, this seems to 
be first report of blight disease (Curvularia lunata) of rice from U.P, India. The fungus was identified as Curvularia lunata 
from Indian type culture collection identification, IARI (ID No. 9062). The pathogenicity of pathogen has been proved by 
the Koch's postulates method. 

KEYWORDS: Rice, Oryza sativa, Leaf, Sheath, Kernels Symptoms and Curvularia lunata 

Rice is the most important cereal crop grown all over the world. During cultivation of rice variety Pant-12, at the 
tillering stage a new rice disease was observed at central field of Sam Higginbottom Institute of Agriculture, Technology 
& Sciences. The brown spots appeared on the tillering rice plants. The rice plants were cultivated using standard 
agronomic practices [7]. 

The first symptoms appeared on the leaves. Elliptical brown spots were observed. The spots increased in size on 
leaves. Gradually the colour of the spots changed to brownish black. The length of spots ranged from 0.2 tolcm (Figure 1). 
Later the spots appeared on leaf sheath which were dark brown initially with yellow margin and the diseased sheath 
became yellow and blighted. Initially these spots were similar to the ones on the leaf but later covered the whole leaf 
sheath (Figure 2). Gradually the disease spread to the kernels. Glumes were discoloured and in severe infection, the rice 
kernel showed black discoloration (Figure 3). 

Figure 1: Disease Symptoms Figure 2: Disease Symptoms Figure 3: Disease Symptoms 
on the Leaves on the Leaf Sheath on the Kernels 


Kamaluddeen, Sobita Simon & Abhilasha A. Lai 

Micro-scopical examination revealed the presence of conidia of the fungus. The conidia were four celled and 
generally curved, second cell larger with two middle cells darker than the paler end cells. Conidiophores were branched, 
septate and dark in colour. 

Isolation of the fungus from the infected parts was carried out on PDA (Potato Dextrose Agar) plates following 
the standard methodology [1]. After two-three days whitish mycelial growth appeared which gradually became greyish 
black in colour (Figure 4). 

Figure 4: Pure Culture of Curvularia lunata 

Microscopical examination of fungal culture again showed the presence of same type of conidia and 
conidiophores as mentioned earlier. The morphological characters of the fungus closely resembled those described by [2] 
and [8] as Curvularia lunata. The fungus was identified as Curvularia lunata from Indian type culture collection 
identification, IARI (ID No. 9062) (Figure 5). The pathogenicity of pathogen has been proved by the Koch's postulates 
method [1]. 

Figure 5: Conidiophores & Conidia of Curvularia lunata 

Perusal of literature revealed that incidence of Curvularia lunata. has been reported on rice grains discoloration 
[3], leaf spot [6], seedling blight [5] and sheath rot also reported by [4] in Tamil Nadu, India. Whoever, blight disease due 
to this pathogen has not been reported previously, and this seems to be first report of a new blight disease of rice from 
Uttar Pradesh. 

A New Blight Disease of Rice Caused by Curvularia lunata from Uttar Pradesh 15 


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(P) Limited, Publishers. New Delhi. 439-447 pp. 

2. Boedijn, K. B. (1933). Ueber einige phragmosporen dermatiazeen. Bulletin du Jardin botanique de Buitenzorg. 
Series 3(13): 120-134. 

3. Groves, J. W. and Skolko, A. J. (1945). Notes on seed borne fungi. III. Curvularia. Canadian Journal of 
Research, 23:94-104. 

4. Lakshmanan, P. (1992). Sheath rot of rice incited by Curvularia lunata in Tamil Nadu, India. Tropical Pest 
Management, 38 (1):107 

5. Martin, A. L. (1939). Possible cause of black kernels in rice. Plant Disease Reporter, 23:247-249.. 

6. Patwick, G. W. (1950). Manual of rice diseases. [Kew: CMI], p. 198. 

7. Singh, S. S. 2005. Crop Management. Kaly ani Publishers. Ludhiana. 50 pp. 

8. Sivanesan, A. (1987). Graminicolous species of Bipolaris, Curvularia, Drechslera, Exerohitum and their 
teleomorphs. Mycological Papers, 158, 117.