P.K. MALAKER
Senior Scientific Officer
Wheat Research Centre, BARI, Dinajpur-5200,
I.H. MIAN
Professor
BSMRAU, Gazipur-1706, Bangladesh.
Seed treatment, Foliar spray, Black point, Wheat
Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Salna, Gazipur
Pest Management
The experiment was conducted at Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Salna, Gazipur, during 1999-2000 crop season. The seeds of a susceptible variety ‘Kanchan’ were collected from BARI and treated separately with two seed treating fungicides, namely Vitavax-200 (Carboxin 37.5% + Thiram 37.5%) and Homai 8OWP (Thiophanate methyl 50% + Thiram 30%) at the rate of 2.5 g/kg of dry seed weight. As foliar spray, Tilt- 250EC (Propiconazole) at 0.05% concentration of the formulated product was applied under six different spray schedules viz., i) 30, 50, 70, and 90 days after sowing (DAS); ii) 30, 45, 60, 75, and 90 DAS; iii) 30, 40, 50, 60, 70, 80, and 90 DAS; iv) 70 and 90 DAS; v) 60, 75, and 90 DAS; and vi) 60, 70, 80, and 90 DAS. Untreated and unsprayed controls were also maintained. The land was prepared using a tractor driven disc plough, rotavator, and harrow. Well decomposed cowdung was applied at the rate of 10 t/ha. Urea, TSP, MP, and gypsum were used at the rate of 220, 132, 68, and 125 kg/ha, respectively. Full doses of TSP, MP, and gypsum and two-thirds urea were applied during final land preparation. The rest one-third urea was applied as top dress after 20 days of sowing. The experiment was laid out in split-plot design with three replications. Seed treatment was assigned in the main plots and foliar spray in the sub-plots. The unit plot size was 2m x 3m. Plot to plot and block to block distances were 1.0 m and 1.5 m, respectively. The seeds were sown at the rate of 120 kg/ha in continuous manner with 20 cm row spacing. Weeding was done twice at 25 and 45 DAS. Irrigations were applied at 20, 42, 63, and 80 DAS. Data on seedling emergence per square meter were recorded after two weeks of sowing by counting the total number of seedlings in five linear meter selected randomly from middle five rows of each plot. Observations on post-emergence mortality were taken after three weeks of sowing in the same manner as followed for seedling emergence. Plant population was calculated by deducting the number of dead seedlings from those emerged per square meter. Number of spikes per square meter was noted before harvest following the same procedure as used for seedling emergence and post-emergence mortality. The crop was harvested at 115 DAS and data on black point infection of seed, length and weight of spike, number of grains per spike, 1000-grain weight, and grain yield were recorded. Black pointed grains per spike were recorded from 20 spikes selected randomly in each plot. Percentage of black pointed grains was calculated from 400 grains of composite sample taken from each plot. The grains were indexed for black point infection using 0-5 scale suggested by Gilchrist (1985). Data on disease parameters, yield and yield components were analyzed statistically using MSTAT-C computer programme and means were compared by DMRT. Economic analysis on yield advantage obtained from foliar sprays was also performed.
Bangladesh J. Agril. Res. 34(3) : 425-434, September 2009, ISSN 0258-7122
Journal