ASSESSMENT OF SOME BIOPESTICIDES AGAINST INSECT PESTS OF CHICKPEA AND THE EFFECTS ON THEIR NATURAL ENEMIES

Abstract

A research work was operated during the rabi season, the November, 2021 to March, 2022 in the experimental field of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka, to assess of some biopesticides against insect pests of chickpea and the effects on their natural enemies. BARI chola-9 chickpea variety was selected as the test crop for this experiment. Eight different treatments were considered and three times in a field setting that was comparable and the experiment was set up using a Randomized Complete Block Design (RCBD).The treatments are T 1 = Blue sticky trap +Bio-max M 1.2EC @ 1.0 ml/L of water at 7 (Seven) days interval; T 2 = Yellow sticky trap + Imitaf 20SL @ 1.0 ml /L of water at the 7 (Seven) days interval; T 3 = Yellow sticky trap + Spinomax @ 2.0 ml/L of water at 7 (Seven) Days interval; T 4 = Field sanitation + Bio Bt k @ 0.5gm/L at 7 (Seven) days interval; T 5 = Fytomax N @ 5ml/L of water at 7 (Seven) days interval; T 6 = Field sanitation + pheromone trap @ 1 trap/plot at 30 (Thirty) days interval; T 7 = Spraying HNPV@ 0.3gm/L of water at 7 (Seven) days interval; T 0 = Untreated control. According to treatment performance, the lowest pest infestation was observed in T 2 (7.57/ leaf/plant, 7.24/leaf/plant) and T 3 (3.44/10plants, 3.34/5m 2 ) treatments against sucking pests (aphid, whitefly) and lepidopteran pests (chickpea pod borer, tobacco caterpillar) of chickpea respectively. T 2 and T 3 treatments were most effective against sucking and the lepidopteran insect pests of chickpea. In natural enemies, the maximum number of lady bird beetle and predatory spider (11.66/5m 2 and 8.00/ 5m 2 ) was recorded from T 3 treatment. In addition, the maximum reduction over control in case of plant and pod infestation were found in T 3 treatment (64.52% and 84.68% respectively) whereas the minimum reduction were (17.48% and 25.42% respectively) in T 5 Treatment. In term of yield of chickpea, the maximum yield (2.35 t/ha) was recorded from T 3 treatment and followed by T 1 (2.19 t/ha) treatment. So, it can be summarised that treatment T 3 (Yellow sticky trap + Spinomax @ 2.0ml/L of water at 7 (Seven) days interval) was more successful than the other treatments and T 1 came after it.