Effect of Meloidogyne incognita on the emergence and growth of soyabean seedlings and the relationship between seedling age and nematode invasion

Soil population densities of Meloidogyne incognita upto 32 J2/cc soil did not suppress or delay the emergence of soyabean seedlings. The growth of seedlings was suppressed at inoculation levels of 4 or more J2/cc soil. The total number of juveniles invading the root increased with the level of inoculation, incubation period and the age of the seedlings. However,there was a shift in the period of peak invasion from 3–24 hr in 2 day old seedlings to 24–48 hr in 11 day and 48–96 hr in the 21 day old seedlings. The extent of juvenile invasion was proportional to the number of new growing roots.