Abiotic Factors as Game Changer in Sex Ratio Distortion of Insects
Sweta Verma
Division of Entomology, ICAR-Indian Agricultural Research Institute, New Delhi- 110012, India.
Doddachowdappa Sagar *
Division of Entomology, ICAR-Indian Agricultural Research Institute, New Delhi- 110012, India and Division of Genomic Resources, ICAR- National Bureau of Agricultural Insect Resources, Bengaluru-560024, India.
Hemant Kumar
Division of Entomology, ICAR-Indian Agricultural Research Institute, New Delhi- 110012, India.
Sujatha G S
Division of Entomology, ICAR-Indian Agricultural Research Institute, New Delhi- 110012, India.
*Author to whom correspondence should be addressed.
Abstract
Sex ratios in insect populations are critical in shaping their reproductive dynamics, genetic diversity, and ecological interactions. While genetic factors often determine sex, abiotic factors have emerged as important influencers of sex ratios in insects. The influence of abiotic factors on sex ratios in insects is of scientific interest and holds practical implications for insect conservation and management. As environmental conditions change due to global warming, understanding how sex ratios respond to these changes can aid in predicting population dynamics and designing effective conservation strategies for biocontrol agents as well as the management of insect pests. Abiotic stressors, including fluctuations in temperature, humidity variations, altitude & latitude, nutrition and chemical exposure have been shown to disrupt the precise balance of hormonal and genetic cues governing sex determination in insects. Insects being ectothermic, body temperature depends on the surrounding environmental conditions and are highly vulnerable to the change in climate. This review explores the intricate relationship between abiotic stress and sex determination mechanisms in insects, highlighting recent advances in our understanding of how stress-induced alterations especially environment in hormone signaling, gene expression, and epigenetic modifications can lead to skewed sex ratios and developmental anomalies. Regardless of the advances in this area, notable research gaps are still present. Future studies on the multiple abiotic factors and their synergistic effects will give a more detailed study of insect populations, and their ecosystems. This comprehensive review delves into the multifaceted interactions between abiotic factors and sex differentiation in insects. In conclusion, the abiotic factors especially temperature are indeed game changers in the insect sex ratio dynamics.
Keywords: Abiotic factors, sex ratio, epigenetics, juvenile hormone, metamorphosis