Abstract:
A study was undertaken to evaluate the efficacy of plant extracts to control Bipolaris leaf
blight (Bipolaris sorokiniana) and increasing grain yield of wheat. Water extracts of
neem (Azadirachta indica). 'allamanda'(Allamallda cathartica), 'mehedi'(Lawsonia alba)
leaves, 'bishkatali' (Polygonum hydropiper) shoot, 'garlic'(Allium sativum) clove, onion
(Allium cepa) bulb, black cumin (Nigella sativa) seed, and ginger (Zingiber officinalis)
rhizome were prepared at a concentration of I :2. Wheat seeds were treated with individual
plant extracts. Seeds were also treated with Vitavax-200 for comparison. It was found that
all the plant extracts except mehedi increased seed germination on blotter. A remarkable
reduction in incidence of seed borne Bipolaris sorokiniana was achieved with the
botanicals. The disease severity was the lowest under Vitavax-200, followed by bishkatali
and garlic extract. The highest disease severity was recorded under control. The increasd
grain yield over control was achieved with extracts of onion, garlic, black cumin, ginger,
bishkatali and neem. The efficacy of plant extracts to decrease disease severity and to
increase zrain vield was more or less similar to that of Vitavax -200.
