SEASONAL POPULATION DYNAMICS OF TYLENCHULUS SEMIPENETRANS IN CITRUS ORCHARD, NARC, ISLAMABAD

Abstract

Tylenchulus semipenetrans Cobb, the citrus nematode occurs in all the citrus growing regions of the world. Population dynamics directly effects the production and citrus industry under wide range of environmental and edaphic conditions. The continuous information on seasonal fluctuation of the nematode population may help in devising the effective management strategies at the right time. In the current study trees were selected after intensive pre-sampling at NARC, Islamabad. The soil and root samples were collected from July 2006 to June 2007. Samples in triplicate were randomly collected with the help of soil sampler from the canopy of citrus tree, each weighing about 500 g of soil from 5, 15, and 45 cm depth around the roots. Results show that maximum population occurs at the depth of 15 cm while minimum occurs at 5 cm. The highest population was recorded in the month of May while the lowest population was recorded in December.