Viral Threats Endanger Onion and Garlic Crops in Pakistan

Green Pakistan - گرین پاکستان , / Monday, August 18th, 2025

rki.news
Muhammad Zubair Hamza, Dr. Muhammad Ashfaq
MNS University of Agriculture, Multan

A new study by scientists at MNS University of Agriculture, Multan, has revealed alarming levels of viral infections in onion and garlic crops across Punjab and Islamabad, raising concerns for food security, farmer incomes, and export potential.
Conducted over two growing seasons from 2019 to 2021, the research involved surveys in 14 districts and the Islamabad Capital Territory. Of 4,500 leaf samples collected, more than half (53%) tested positive for viral infections. Onion Yellow Dwarf Virus (OYDV) was the most widespread, detected in 44.5% of samples, followed by Iris Yellow Spot Virus (IYSV) at 38.8%. Garlic crops were also found infected with Allexiviruses such as Garlic Virus C and Garlic Virus D.
Onion infection rates ranged between 52.8% and 55%, while garlic crops showed up to 53% prevalence. Molecular testing confirmed that Pakistani viral strains share striking genetic similarities with those from China, the United States, India, and New Zealand, suggesting cross-border spread or common origins. One OYDV strain shared 98% identity with a previously reported Pakistani garlic isolate, while IYSV showed close ties to global samples.
Notably, researchers identified two recombination events in IYSV isolates, a process that could create more aggressive virus strains, raising significant biosecurity concerns. Compounding the challenge, all local onion and garlic cultivars tested were found susceptible, leaving farmers highly vulnerable. The spread is fueled by insect vectors such as aphids and thrips.
Experts are calling for urgent development of resistant crop varieties, integrated pest management, and stricter quarantine protocols to prevent the introduction of new virus strains. Farmer awareness campaigns on early detection, use of virus-free planting material, and insect control are also strongly recommended.
Given the central role of onion and garlic in Pakistan’s diet and exports, researchers warn that unchecked viral spread could increase food prices and severely impact national food security. International collaboration is deemed essential for monitoring and controlling these plant viruses.