EFFICACY OF SELECTED PLANT EXTRACTS ON LEAF SPOT (Blpolaris sorokinianai AND GRAIN YIELD OF WHEAT

Abstract

Efficacy of selected plant extracts was studied on t the leaf spot tBipolarts sorokiniana) and grain yield of wheat during December, 2005 to April, 2006. The experiment was conducted in the laboratory and in the farm of the Sher-e-Bangla Agricultural University,· Dhaka. Ten different treatments viz. T I (control), T2 (Vitavax 200 @ 0.3 %), T) (Onion bulb extract 1:2 w/v), T4 ( Garlic clove extracts 1:2 w/v), T, (Kalizira extracts 1:2 w/v), T6 (Zinger Rhizome extracts 1:2 w/v), T7 (Allamanda leaf extract 1:2w/v), Ts (Bishkatali extracts 1:2 w/v), T9 (Neem leaf extract 1:2 w/v) and TIO ( Mehedi leaf extracts 1:2 w/v). Were explored in the experiment in the laboratory the plant extracts were used in three concentrations i.e. 1: 1, 1:2 and 1:4 w/v. All the plant extracts except Mehedi increased seed germination in ·the laboratory in compared to untreated control. The highest incidence of seed borne Bipolaris sorokiniana was recorded under control (T). A remarkable reduction of the incidence of fungi was achieved by treating seeds with botanicals. The leaf spot severity of flag leaf and penultimate leaf and 3rd leaf differed significantly from one treatment to another at flag leaf, flowering, milking and hard dough stages. The lowest severity of flag leaf in every stage was found in treatment T2 followed by treatment Ts and treatment T4. The highest disease severity of flag leaf, penultimate leaf and third leaf in all growth stages was recorded under the treatment TI (untreated control). Significantly the highest plant height (85.77 ern) and distance between the point of flag leaf initiation and base of ear (15.62 em) were found in the treatment T4, ear length (19.98cm) in treatment Tg, number of tillers/plant (6.48) in treatment TIO, number of spikes/plot (513.66) were found under the treating seeds with botanicals. But the highest number of grains/ear (43.98), weight of grains/ear (1.88g), grain yield (3.52 t/ha) and straw yield (6.85 tlha) was found in T2~ Extract. of Onion, Garlic, Kalizira, "Zinger, Bishkatali and Neem resulted statistically similar grain yield as of seed treatment with Vitavax-200 (T2)'