Greg Constable and I have previously shown that in the Namoi Valley an irrigation water supply of 8 ML per ha is needed to obtain maximum yields in the driest years.

Factors which influence the efficacy of an NPV application These include: (i) the initial actjvity of the virus preparation, distribution (.i.i) lts rate or application and distribution on the crop, (Jji) Its persiste

As a result of a major fall in world cotton prices, the Namoi Cotton Co-operative has been actively looking at ways of reducing costs on cotton farms.

Several factors influence the nitrogen demands of a cotton crop and the ability of the soil and fertiliser to satisfy these demands. Some of these factors (eg weather) are beyond the control of a cotton grower.

Egg parasites of the genus Trichogramma arH used to control lepidopterous pests throughout the world (Stinner, 1977). These small parasitic wasps are released in large numbers (e.g.