Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2005
Publication Date: 6/1/2005
Citation: Navi, S., Bandyopadhyay, R., Tonapi, V., Rao, T., Reddy, R., Tooley, P.W., Thomas, D. 2005. Prevalence of major diseases of sorghum in deccan regions of india. Phytopathology 95:574
Technical Abstract: Extensive on-farm disease surveys were conducted from August 1999 to March 2001 in four sorghum growing states of Indian Deccan plateau. A total of 965 fields were surveyed covering 228 fields in Andhra Pradesh (AP), 406 in Karnataka (KAR), 290 in Maharashtra (MH) and 41 in Tamil Nadu (TN). Among 14 foliar diseases observed, maize stripe virus (MStV), a tenuivirus transmitted by Peregrinus maidis, and among five panicle diseases, ergot (Claviceps spp.) were the most destructive diseases in decreasing order of prevalence across states. MStV was prevalent in 8.9% of fields surveyed in AP, 28.3% in KAR, 44.5% in MH and 31.5% in TN, and the values for ergot were 30.7%, 9.6%, 11%, and 2.4% respectively. The mean incidence of MStV varied from 5% to 12% and the severity from 67% to 85%, while the incidence of ergot varied from 30% to 100% and the severity from 67% 100%. Variation in frequency of occurrence of MStV and ergot was observed between 1999–00 and 2000–01 where pattern variation could be due to weather factors, cropping pattern, vector survival and host specificity. An ergot epidemic was observed during the 1999 rainy season in Maachinenipalli village (16º35'N and 78°37'E), AP. In September 2000, the disease had spread to 13 neighboring administrative zones damaging about 130,000 ha. This paper elucidates the distribution of diseases observed between 1999 and 2001, but does not imply that the diseases are restricted necessarily to a particular zone or location.