Seasonal incidence of Meloidogyne incognita infesting Grape in field

Statistically designed trial was conducted to study the seasonal incidence of root-knot nematode on well-established grape garden infested with root-knot nematode. It was observed that maximum population (1200 J₂/200 cm³ of soil), number of root galls (127.0/5 g roots) and egg masses (114.0/5 g roots) were recorded in 52^nd meteorological week (2^nd fortnight of December), when maximum and minimum temperatures of air were 26.60 and 8.35°C, respectively. While, morning and evening temperatures of soil were 16.78 and 24.88°C, respectively. However, the minimum population of root-knot nematode (80 J₂/200 cm³ of soil), number of root galls (7/5 g of roots) and egg masses (6/5 g of roots) were recorded in 21^st meteorological week (2^nd fortnight of May), when maximum and minimum temperatures of air and morning and evening temperatures of soil were 39.35 and 26.70°C and 29.70 and 39.98°C, respectively. This study indicated that there were highly significant negative correlation between root-knot nematode population, number of root galls and egg masses with maximum and minimum temperatures of air and soil.