Influence of soil salinity on reproduction and multiplication of root-knot nematode (Meloidogyne incognita) in cotton

A screenhouse study was undertaken to study the effect of soil salinity (electric conductivity)/ECe on root-knot nematode, Meloidogyne incognita in cotton, Gossypium hirsutum cv. H-777. Four different salinity/ECe levels viz. 2.8, 5.6, 8.4 and 11.2 dS/m were prepared by dissolving calculated amounts of sodium sulphate, calcium chloride and magnesium chloride (4:1:3) in 250 ml of distilled water and then added to potted soil followed by seed sowing and nematode inoculation @ IJ2/g soil. Non-saline soil (ECe 1.15) served as check. At each ECe level, two sub treatments i.e. nematode inoculated and non-inoculated were kept. The results recorded 90 days after inoculation, revealed that the growth parameters of cotton plants were maximum in non-saline check which decreased with increase in ECe levels from 2.2 to 11.2 dS/m under nematode inoculated as well as non-inoculated conditions. Nematode galling, egg masses, eggs/egg mass and final nematode population in the soil also decreased with increased ECe levels from 5.6 to 11.2 dS/m as compared to non-saline (ECe 1.15) check and 2.8 dS/m.