Population behavior and distribution pattern of Tylenchorhynchus zeae and Hoplolaimus indicus in cultivated soil receiving industrial pollutants

Field population of Tylenchorhynchus zeae and Hoplolaimus indicus was estimated in a sewage-fed field and compared with that of a non-sewage-fed field having the same cropping sequence and their pattern of distribution was studied with the help of Taylor's Power Law (faylor, 1961). T. zeae was the numerically dominant species and was recovered maximum from sewage-fed paddy and minimum from non-sewage-fed mustard. Sewage-fed field supported nematode population several times more than the non-sewage-fed field.

Tylenchorhynchus zeae showed least aggregation in the crop-containing sewage-fed field; value of Taylor's Power Law being 1.14. Aggregation was maximum in the non-sewage-fed plot lying fallow = 2.0. Similarly, Hoplolaimus indicus showed least aggregation in the sewage-fed crop field, giving a value of 1.33 while during fallow, the value reached as high as 3.2. Thus, the distribution pattern tended to be random at higher population densities.