Survey, Pathogenic Effect and Management of Root- Knot Nematode, Meloidogyne incognita on Okra

Survey of okra fields were conducted for the occurrence of economically important plant parasitic nematodes of some localities of Jammu and Samba district of J&K.Among the different plant parasitic nematodes Meloidogyne spp. was more frequently encountered in maximum localities of Jammu and Samba districts. Experiment was conducted to find out the effect of different inoculum levels of nematode and effect of nematicides on the plant growth and nematode multiplication in pot condition on okra plant. Significant reduction occurred in plant growth parameters viz., shoot length, root length, shoot and root mass, dry shoot mass and number of leaves of plant inoculated with 500, 1000 and 2000 juveniles/pot. The highest gall index was recorded at inoculum levels of 1000 and 2000 respectively. Total nematode population/pot significantly increased progressively with an increase in nematode population from 20–2000 J2/pot. Reduction in multiplication of the nematode was observed with increase inoculum levels. Application of nematicides significantly increased plant growth and decreased the host infestation by root-knot nematode, Meloidogyne incognita over control. Maximum plant height was recorded in carbofuran @1.5 kg a.i/ha treated soil followed by carbofuran 1.0, phorate1.5, and phorate 1.0 kg a.i/ha respectively. However, no more differences between carbofuran 1.5 kg a.i/ha and phorate 1.0 kg a.i/ha at plant growth and nematode multiplication levels. The minimum population was recorded in carbofuran at1.5 kg a.i/ha and maximum population in phorate at 1.0 kg a.i/ha treated soil. The both nematicides are effective as a form of chemical control measures. The maximum reduction emergence of juveniles from M. incognita was noted at 40 ppm concentration of carbofuran.