M. M. Kamal
Scientific Officer
Spices Research Center,BARI, Shibganj, Bogra
M. M. Hossain
Scientific Officer
Spices Research Center,BARI, Shibganj, Bogra
D. Sarker
Principal Scientific Officer
Entomology division,BARI, Gazipur
A field experiment was conducted at SRC, Bogra during rabi season, 2012-2013 to test the efficacy of different bio-pesticides against thrips in onion. The test crops were BARI Onion-4. The experiment was laid out in a randomized complete block design with three replications. Four bio-pesticides viz. Neem seed extract @50g/L of water (T1); Tobacco leaf extract @10g/L of water (T2); Neem oil @4ml/L of water (T3) and Spinosad (Tracer 45SC) @ 0.4ml/L of water (T4) including untreated control (T5) were studied in this experiment. Application of spinosad gave better control against thrips over other treatments. The highest percentage of thrips population reduction (85.10%) was also observed from Spinosad (Tracer 45SC) treated plot. The highest bulb yield (17.40 t/ha) was obtained from the plot treated with Spinosad (Tracer 45SC) @0.4ml/L of water followed by neem seed extaxt@50g/L of water (15.00 t/ha). The highest MBCR (12.88) was also obtained from the plot treated with Spinosad (Tracer 45SC).
BIO-PESTICIDES, MANAGEMENT, ONION THRIPS (Thrips tabaci).
Spices Research Center,BARI, Shibganj, Bogra
Variety and Species
To find out the best performing organic insecticide against thrips in onion.
The field experiment was conducted at SRC, Bogra during rabi 2012-2013 to find out the best performing organic insecticide against thrips in onion. The experiment was laid out in a randomized complete block design with three replications. The test crop was BARI Onion-4. Four bio-pesticides viz. Neem seed extract @50g/L of water (T1); Tobacco leaf extract @10g/L of water (T2); Neem oil @4ml/L of water (T3) and Spinosad (Tracer 45SC) @ 0.4ml/L of water (T4) including untreated control (T5) were studied in this experiment. Thirty seven day old seedlings were transplanted on 26 December 2012. Unit plot size was 4m × 1.2m and spacing was 15cm X 10cm. Three weedings were done at 15, 25 and 45 DAT. Four irrigations were done at 15, 25, 40 and 55 DAT. The crop was fertilized with 5 t/ha of cow dung, N110P52K75S20Zn4B1.5kg/ha. The entire amount of cow dung P, S, B, Zn, 1/3 N and ½ K was applied during land preparation. The rest N and K was applied in two equal splits at 25 and 50 DAT). The crop was harvested on 25 March 2013. The trial consisted of 5 treatments and each plot consisted of 8 lines and 40 plants. Thrips population was counted at 7 days interval from the first appearance of thrips infestation. Number of thrips (both adult and nymphs) was counted from 15 randomly selected plants of each plot. All recommended agronomic practices were followed for the production of onion. Crop yield data were also recorded immediately after crop harvest. Data on thrips population and yield were analyzed using MSTAT-C program and mean values were separated by DMRT.
Annual Research Report 2012-13, Spice Research Center, BARI, Shibganj, Bogra
35,000/-
It is revealed from the study that all the treatment significantly reduced thrips population over control. After first spray, lowest number of thrips population (4.57 thrips/plant) and maximum thrips population reduction 75.94 % over control was observed from Spinosad (Tracer 45SC @0.4ml/L of water) treated plot followed by Neem seed extract treated plot (6.66 thrips/plant and 64.94% reduction over control) and Neem oil treated plot(7.55 thrips/plant and 60.26% reduction over control). After second spray more or less similar trend of result was also observed among different management options. After third spray, the best thrips control was obtained from the Spinosad treated plot (4.75 thrips/plant) followed by Tobacco leaf extract treated plot (12.01 thrips/plant) and Neem seed extract treated plot (12.23 thrips/plant). Spinosad treated plot showed highest yield (17.40 t/ha) which was identical to neem seed extract (15.00 t/ha) but differed significantly from other treatments. This was due to better thrips control by these treatment. The highest MBCR (12.88) was obtained from plot treated with Spinosad (Tracer 45SC) which was closely followed by Neem seed extract (11.43) and tobacco leaf extract treated plot (10.06).
Spinosad (Tracer 45SC)@0.4ml/L of water were most effective in controlling thrips problem in onion with higher yield and maximum MBCR.
Report/Proceedings