Effect of tillage on termites, weed incidence and productivity of spring wheat in rice-wheat system of North Western Indian plains

Weeds and termites are the important pests of wheat in North West India affecting yields. With the introduction of new tillage systems for growing wheat, the pest situation is likely to change due to a change in microclimate. Studies were thus undertaken to evaluate the effect of tillage options in rice and wheat on the incidence of termites and weeds in wheat (Triticum aestivum L. emend. Fiori and Paol.). For wheat, four tillage options, i.e., conventional, FIRBS (furrow irrigated raised bed-planting system), zero tillage and rotary tillage; were superimposed on four tillage options in rice (conventional puddling with harrow, dry field preparation with harrow, dry field preparation with rotavator and puddling with rotavator). The incidence of termites was significantly higher in FIRBS compared to other three tillage options for growing wheat, whereas tillage in rice had no effect. Similarly, the weed population was influenced by tillage options. Dicot weeds increased in zero tillage while FIRBS and conventional tillage had more monocot weeds. The incidence of termites was higher during the drier year. Tillage practices in rice had no effect on wheat during both years but tillage in wheat significantly affected its yield with the highest recorded from rotary tillage. (C) 2004 Elsevier Ltd. All rights reserved.