Habitat Manipulation with Buckwheat and Coriander Strips Improves Conservation Biological Control of Rhopalosiphum Padi in Wheat in Peshawar
Year: 2026
Type: article
Abstract: Background: The bird cherry oat aphid (Rhopalosiphum padi) is a major pest of wheat in Peshawar, causing 20–40% yield losses through direct feeding and transmission of Barley yellow dwarf virus. Smallholder farmers rely heavily on broad-spectrum insecticides, leading to resistance, natural enemy destruction, and health risks. Conservation biological control using flowering strips offers a sustainable alternative, but locally validated species and mixtures are lacking for Khyber Pakhtunkhwa. Methods: A field experiment was conducted at the Agronomy Research Farm, The University of Agriculture Peshawar, using a randomized complete block design with four replications. Four treatments were compared: control (bare margins), buckwheat strip, coriander strip, and mixed strip (buckwheat + coriander + sweet alyssum). Weekly observations recorded aphid density (per tiller), predator abundance (coccinellids, syrphids, chrysopids), grain yield (t/ha), thousand grain weight (g), and benefit-cost ratio (BCR). Results: The mixed flowering strip reduced peak aphid density to 46.9 ± 3.1 per tiller, a 45% reduction compared to the control (85.4 ± 5.2). Total predator abundance was highest in the mixed strip (15.8 ± 1.2 per 10 tillers), more than three times that of the control (5.1 ± 0.6). Grain yield followed the same pattern: mixed strip (4.85 t/ha, +26% over control), coriander (4.52 t/ha, +17%), buckwheat (4.48 t/ha, +16%), and control (3.85 t/ha). Thousand grain weight was also highest in the mixed strip (43.4 g). The benefit-cost ratio was substantially higher for the mixed strip (4.2) compared to single-species strips (2.1–2.3) and the control (1.0). Conclusion: Mixed flowering strips (buckwheat + coriander + sweet alyssum) significantly increase pred ator abundance, suppress aphid populations, and improve wheat yield under Peshawar conditions. This low-cost, ecologically based practice is recommended for integration into wheat IPM programs, reducing reliance on hazardous insecticides while enhancing farm profitability and biodiversity.
Language: English
Subfield: Insect Science
Domain: Life Sciences
SDGs: Zero hunger, Life on land
Open Access status: hybrid
OpenAlex ID: W7164155594