The study was conducted at the Research Field of Entomology Department, Sylhet Agricultural University (SAU) campus and farmer’s field at Sreemangal, Moulvibazar during October 2017 to April 2018 to find out the effectiveness of net barrier in protecting major insect and mite pests of bell pepper. Four treatments viz., plot with coarse net (40-mesh mosquito net) + polyethylene (T₁), plot with fine net (120-mesh nylon net) + polyethylene (T₂), plot with polyethylene (T₃) and control plot (T₄) were used. The experiments were laid out in a Randomized Complete Block Design with five replications. In two sites, chili aphid (Aphis gossypii Glov.), jassid (Amrasca biguttula Ishida), common cutworm (Spodoptera litura Fab.) and white mite (Tetranychus sp.) were found as the major pests. Irrespective study sites, coarse net and fine net reduced 73 to 80% chili aphid, 51 to 74% jassid and 71 to 81% white mite. The treatments had no impact on reducing common cutworm. In both sites, highest fruit yields were obtained from fine net and polyethylene plot in SAU (12.74 t ha^-1) and also in Sreemangal (10.48 t ha^-1). The fine net plot gave higher Marginal Benefit Cost Ratio (MBCR) in SAU campus (MBCR = 7.56 : 1) and Sreemangal (MBCR = 4.9 : 1). The results indicated that fine net use in bell pepper plot is effective in controlling insect and mite pests, producing higher fruit yield and profits.

Keywords: Capsicum, sweet pepper, insect, mite, poly-tunnel

A popular sweet pepper variety ‘California Wonder’ was evaluated under different protective structures in two consecutive seasons of 2008-09 and 2009-10 at the experimental field of Horticulture Research Center (HRC) of Bangladesh Agricultural Research Institute (BARI), Gazipur. Protective structures had remarkable and significant influence on plant growth and yield of the sweet pepper. The plants grown under tunnel cover with polythene and nylon net or tunnel cover with only nylon net had higher plant height compared to that of plants grown in open field. In both of the seasons the highest individual fruit weight (76.13g and 73.71g, respectively) was recorded from the plants grown under tunnel cover with polythene and nylon net while it was the lowest from open field grown plant (45.44g and 48.2g, respectively). The highest number of fruits per plant was recorded in both seasons from the plants grown under tunnel cover with polythene and nylon net and it was closely followed by tunnel cover with only nylon net. The maximum fruit yield per plant (550.1g) was recorded in 2009-10 from tunnel cover with polythene and nylon net which was followed by tunnel cover with only nylon net (439.58g). The lowest per plant fruit yield was obtained from the crop grown in open field (125.1g) indicating brighter scope for sweet pepper cultivation under protective structures.

Keywords: Sweet pepper, protective structures, polythene, nylon net