Economic assessment of yield loss of garlic due to leaf blotch disease

Abstract

Abstract : Yield reduction of garlic and economic loss incurred due to leaf blotch disease were determined by the foliar application of Rovral 50WP at Regional Agricultural Research Station, Jessore under natural epiphytotic conditions for three consecutive growing seasons (1990-91, 1991-92 and 1992-93). The disease severity, yield and yield parameters varied significantly (p=0.05) between the sprayed and unsprayed plots. The disease severity ranged from 26.69 to 38.12% and 74.81 to 80.22% for the sprayed and unsprayed plots respectively. The bulb yield of garlic reduced significantly in ail the years with the increase of disease severity. The yield loss increased at the rate of 10.35 kg/ha per unit increase of disease severity. The average yield reduction over the years was estimated to the tune of 21.54 per cent. The highest yield loss (23.07%) was recorded in 1991-92 while the lowest (19.66%) in 1990-91. The yield reduction was contributed by the significant losses in biomass and bulb weight. A substantial monitory loss amounting Tk.7,245 /ha was incurred due to reduction in bulb yield of garlic. The highest economic loss of Tk.8,745 /ha was estimated in 1991-92 followed by that of Tk. 8,235 and 4,755/ha in 1992-93 and 1990-91 respectively.