Abstract:
Rice diseases are considered to be the major limiting factor in rice production and improper
control measures without definite knowledge on rice diseases result in higher cost of
production. The main aim of the study was to evaluate rice diseases in selected
G.N.divisions of Sithandi, Karadiyanaaru and Eravur. 75 random paddy farmers were
interviewed with structured questionnaire. Followed by a quadrate (1’×1’) was used to
assess the type of diseases prevailed in the field. Disease prevalence was calculated as the
proportion of fields showing the disease, out of the total number of fields assessed. Disease
incidences were determined as the proportion of plants showing symptoms, expressed as a
percentage of the total number of plants assessed. From the survey findings it was noted
that 10 rice varieties such as BW 361, BG 360, BG 356, BG 300, AT 308, AT 362, LD 365,
BG 357, BG 358 and BG 352 were cultivated all over the study area. Further, results of the
field assessment revealed that blast and sheath blight were found to be more prevailed
diseases with 88% and 86.7% respectively. Further blast and sheath blight showed highest
incidence with respective percentages of 35.3% and 41.7%. Out of 10 varieties cultivated
across the selected paddy fields, variety AT308 and BG360 were found to be more
susceptible for blast and sheath blight respectively while the variety BG 358 was resistant for
blast and blight. Therefore, farmers in these regions were suggested to cultivate the varieties
which are more resistant for blast and sheath blight compare to others and to adopt field
management practices at optimum levels.
