White tip nematode: Aphelenchoides besseyi Christie

Kannada Name: Bili Tudi Roga

Vernacular Name:

            The white tip nematode affects rice crop grown in humid areas. It is widely distributed and now occurs in most of the rice growing areas.

Period of occurrence : Tillering stage

Extent of yield loss: 30-50%

Symptoms:

• White tip or whip like malformation of the top one-third of the leaf blade.

• In flowering tillers, chaffiness and abnormal elongation of glumes in some spikelets

• Reduced vigour, height and weight of spikelets and number of grains

• Chlorotic/white upto 5.0 cm from tip.

• Nematode multiply on fungi - Alternaria, Helminthosporium Fusarium but without fungi it will not multiply.

• Flag leaf twisted, Late Maturity

Preventive measures:

• Soak the seeds in water for 24 hours, later hot water treatment at 52°C for 10 min

• Resistant genotypes - blue honnet, Tp-49 Toro

• Hot water seed treatment 52 0C for 15 Minutes.

• Pre soak in water 24 hr.

• 51-53 0C for 15 min.

Chemical control:

• Apply carbofuran 3 G @ 33 kg or phorate 10G @ 12.5 kg or fipronil 0.3G @ 33 kg per ha of nursery, 5 to 7 days before pulling the seedlings for transplanting.

• Fumigation  with methyl bromide 1.251b/ 1000 ft3 for 6 hours.