Fotedar's stem nematode

Ditylenchus fotedari is a microscopic plant-parasitic nematode belonging to the order Tylenchida and the family Anguinidae. As an obligate parasite, it primarily resides within the vascular and parenchyma tissues of its host plants. Its slender, vermiform body is adapted for movement through the soil and entry into plant tissues via stomata or epidermal ruptures using its piercing stylet.

The host range of Ditylenchus fotedari includes various bulbous crops and commercial vegetables. The nematode is particularly problematic in intensive farming systems, where continuous cropping provides ideal conditions for population buildup. The pest is disseminated primarily through the movement of infested bulbs, seeds, irrigation water, and contaminated agricultural tools, which can facilitate its spread across large areas.

The life cycle of the nematode is highly responsive to environmental conditions, particularly moisture and temperature. During favorable periods, it reproduces rapidly, completing multiple generations in a single growing season. In adverse conditions, such as desiccation or extreme cold, the nematodes enter a state of cryptobiosis, allowing them to survive for extended periods in soil or dried plant residues until moisture returns.

Damage symptoms often manifest as stunting, deformation, leaf chlorosis, and the rotting of bulbs or tubers. The feeding activity of the nematode disrupts nutrient transport and weakens the plant structure, often serving as an entry point for secondary opportunistic fungal or bacterial infections. This leads to substantial yield losses and a significant decline in the marketability of agricultural products.

Management and protection strategies require an integrated approach:

• Strict quarantine and inspection of planting material.
• Crop rotation with non-host species for a minimum of 3 years.
• Removal and destruction of infested plant debris and weeds.
• Hot water treatment of bulbs to kill internal nematode populations.
• Application of nematicides or biological control agents in severely infested fields.