EFFECT OF PHYSICAL AND CHEMICAL SEED TREATMENTS ON LEAF SPOT (Bipolaris sorokiniana) AND GRAIN YIELD OF WHEAT

Abstract

An experiment was conducted at the Farm of Sher-e-Bangla Agricultural University, Dhaka during the period from December 2005 to April 2006 to study the effect of physical and chemical seed treatments on leaf spot (Bipolaris sorokinianaj and grain yield of wheat.There were ten treatments viz. farmer's stored seed (TI), apparently healthy seed (T2), farmer's stored seed treated with Vitavax-200 @ 0.4% (T3), apparently healthy seed treated with Vitavax-200 @ 0.4% (T4), fanner's stored seed washed with water (Ts), apparently healthy seed washed with water (T6), fanner's stored seed treated with brine solution @ 2% (T7), apparently healthy seed treated with brine solution @ 2% (T8), washed farmer's stored seed treated with brine solution @ 2% (T9) and washed apparently healthy seed treated with brine solution @ 2% (TIO). The highest germination was counted 84.20% and 86.08% respectively at 10 and 15 DAS in the treatment T4 and the lowest germination 49.84% and 55.54% at 10 and 15 DAS, respectively was recorded in the treatment TI that served as control. The lowest disease severity were recorded at panicle initiation stage, flowering stage, milking stage and hard dough _stage under the treatment T4. which were 0.06, 0.19, 0.36 and 0.84, respectively. On the other hand the highest disease severity were recorded at panicle initiation stage, flowering stage, milking stage and hard dough stage under the treatment TI, which were 0.55, 1.21, 1.69 and 2.53, respectively. The highest grain yield (3.5 t/ha) was obtained in treatment T4, which was 75% increased over control (TI).