Vol. 9, Issue 10, Part G (2025)

An experiment entitled “Effect of Canopy Management on Sucking Pests in Bt Cotton under High-Density Planting System” was carried out during Kharif, 2024-25 at the Department of Entomology, College of Agriculture, Latur, to assess the influence of different canopy management practices on the incidence of major sucking pests in Bt cotton (RCH 929 BG-II). The experiment was laid out in a Randomized Block Design (RBD) with seven treatments and three replications, including pruning of monopodia, detopping, and foliar application of mepiquat chloride under HDPS and conventional spacing.

The major sucking pests observed were leafhopper (Amrasca biguttula biguttula), thrips (Thrips tabaci), aphid (Aphis gossypii), and whitefly (Bemisia tabaci), along with their predator lady bird beetle (Coccinella septempunctata). The population of sucking pests appeared from 30 days after sowing (DAS), increased gradually, and reached a peak between 60 to 90 DAS, followed by a decline at later stages.

Among the treatments, HDPS without canopy modification (T₁) recorded the highest mean populations of jassids (6.7/3 leaves), thrips (24.0/3 leaves), aphids (5.05/3 leaves), and whiteflies (8.15/3 leaves). In contrast, the lowest mean populations were recorded in HDPS + pruning of monopodia + mepiquat chloride (T₆) with 4.95, 20.45, 4.25, and 5.75 per 3 leaves, respectively. The conventional planting system (120 × 45 cm) also recorded comparatively lower pest incidence than unmodified HDPS.

The reduction in pest incidence under canopy-managed plots is attributed to improved aeration, light penetration, and a balanced microclimate that are less favourable for sucking pest multiplication. Overall, the study revealed that integrated canopy management involving pruning of monopodia and mepiquat chloride application effectively minimized sucking pest populations and enhanced the ecological balance in Bt cotton under high-density planting conditions.