Symptoms

  • Root knot nematode is a sedentary endoparasite and affects several crops. Very high populations of this nematode are observed in all regions.
  • The predominant species is Meloidogyne incognita Maximum infestations occur during December/January.
  • Typical galls develop on secondary and fibrous roots (Image1).
  • Root system shows extensive necrosis and rotting.
  • Leave become yellow and are defoliated.
  • Vine declines gradually.

Control Measures

  • Use nematode free rooted cuttings raised in soil mixture sterilized by soil solarization.
  • Remove the severely affected vines which are beyond recovery.
  • Treat the planting pit with phorate @ 30g or carbofuran @ 100 g at the time of planting.
  • Apply in soil, Phorate @ 30 g or Carbofuran @ 100 g per vine, twice in a year. Apply first during May/June with the onset on southwest monsoon and second during September/October.
  • Drench the basins with 1% copper oxychloride @ 5-10 L/vine, 2-3 times during the monsoon season.
  • Apply neem cake @ 1 kg/vine.
  • Rake the soil in the basin of the vine lightly without causing damage to the root system, spread the nematicide uniformly in the basin and cover it with the soil immediately. Ensure sufficient soil moisture at the time of nematicide application.
  • A prophylactic application of nematicide is also necessary to check the nematode infestation. For this, make three equidistant holes of 2-3 cm deep in the bag around the cuttings and place Phorate @ 1g/bag or Carbofuran @ 3g/bag in these holes and cover. A light irrigation may also be given to ensure adequate soil moisture.
  • Application of bacterial suspensions of Bacillus macerans or B. circulans prior to planting of the vines or just before the monsoon period in established plants effectively manages root knot nematode..