Biology, Morphology, and Taxonomy of The Wheat Aphid Sitobion Avenae (Fabricius, 1775) under Laboratory Conditions

Abstract

The present study was conducted on the biology, morphology, and taxonomy of the Wheat aphid, Sitobion avenae, under laboratory conditions, Rabi season 2026. The specimens were collected from the Date Palm Research Institute, Agriculture Extension Department, Government of Sindh, Kot Diji, Khairpur, Sindh, Pakistan. Aphid populations were reared at 25±2°C, 65 RH% and 16:8h (light: dark) photoperiod. Four nymphal instars were observed during the study. The total nymphal development period ranged from 7–10 days, with a mean duration of 8.5±0.75 days. The longevity of adult females ranged from 15–25 days, with a mean duration of 20.0±2.50 days and reproduced parthenogenetically, producing approximately 30–70 nymphs during their lifetime. Progressive morphological development was observed throughout the successive instars with a gradual increase in body mean length from 0.60±0.10 mm and 0.25±0.05 mm, in the 1st nymph instar, the mean length of 2nd nymph 0.85±0.15 mm, width 0.25±0.05 mm, 3rd nymph mean length 1.25±0.25 mm, width 0.50±0.10 mm. The 4th nymph mean length 1.75±0.25 mm, width 0.65±0.15 mm. The mean length of adult 3.30±0.70 mm, width 0.80±0.20 mm. Elongate antennae, cylindrical cornicles, elongated cauda, and the presence of alate and apterous forms were important characters for accurate species identification. The biological characteristics indicate rapid population growth and high reproductive potential under favorable conditions. Our findings provide baseline information for understanding the bio-morphological and taxonomic position of S. avenae and developing sustainable integrated pest management strategies. Future studies should focus on the population dynamics, host interactions, and sustainable management of English grain aphid.