Rice White Tip Nematode

Scientific name: Aphelenchoides besseyi

 This is one of the economically important nematode parasite infecting rice crops throughout the world. This nematode was first reported on rice from Japan, and an extensive work has been carried out on this nematode pest.

Symptoms

Feeding at leaf tips in rice results in whitening of the top 3-5 cm of the leaf, leading to necrosis known as "White Tip". There is also distortion of the flag leaf that encloses the panicle. Diseased plants are stunted, lack vigor and produce small panicles. Affected panicles show high sterility, distorted glumes and small and distorted kernels. In the seed-bed, emergence of severely infected seedlings is delayed and germination is low. The most conspicuous symptoms occur at the tillering stage.

Management

• Aphelenchoides besseyi infestations can be avoided by using nematode-free seeds and planting in nematode-free planting material.
• Destruction of infected source of inoculum like seeds,weeds,debris left after harvest in field.
• Chemical treatments of seed have also been reported as being effective in controlling A. besseyi. Benomyl applied as a seed treatment reduced average numbers of nematodes Thiabendazole has also been reported as an effective seed treatment.
• Spraying of infested crop with Parathion (.025%) and Trichlorophos (0.03%) three times has been found to be effective.