NEW DELHI, 9 July 2025: In a major breakthrough for food grain storage and pest management, scientists at the ICAR-Indian Agricultural Research Institute (IARI), New Delhi, have developed a DNA-based test that can rapidly detect phosphine-resistant Red Flour Beetles (Tribolium castaneum)—one of the most destructive pests of stored grains worldwide.

This innovation addresses a long-standing challenge in India’s post-harvest grain management: the increasing resistance of pests to phosphine, a widely used fumigant in warehouses and storage silos.

The Growing Threat of Phosphine Resistance

The Red Flour Beetle is a primary pest affecting stored cereals, flour, pulses, and processed grain products. Over time, excessive and indiscriminate use of phosphine has resulted in insect populations evolving resistance, leading to significant post-harvest losses across food warehouses, especially in humid regions.

Traditional detection methods are time-consuming, labor-intensive, and often ineffective at identifying resistant strains early enough for intervention.

A Quick, Accurate Solution

To combat this, IARI scientists have developed a CAPS marker-based DNA test that offers:

Quick and reliable detection of phosphine-resistant beetles.

Targeted pest control strategies, minimizing the use of chemicals.

Enhanced safety and preservation of stored grains in FCI depots and private warehouses.

The test uses genetic markers to distinguish resistant beetle strains, allowing authorities to act early and prevent infestation spread.

Implications for Food Security and Sustainability

By identifying resistant pests before full-blown outbreaks, this DNA test helps:

Reduce post-harvest food losses, which account for up to 10% of stored grain annually in India.

Minimize chemical usage, lowering environmental impact and chemical residues in food.

Support safer storage protocols for government and private sector stakeholders under schemes like the Food Security Mission and National Food Storage Modernization.

Scientific Impact

Dr. Himanshu Pathak, DG, ICAR, stated, “The development of this molecular tool is a significant leap toward ensuring grain safety in India. It aligns with our vision for precision agriculture and biosecurity.”

The CAPS marker test is expected to be rolled out through ICAR’s network of Krishi Vigyan Kendras (KVKs) and can be incorporated into routine pest surveillance protocols by FCI, CWC, and state warehousing corporations.