Salt mixtures for mirid management

Abstract

Recent trials have shown that reduced rates of insecticide combined with salt have given effective control of mirids — with reduced negative affects on beneficials.

Green and brown mirids have become important mid to late season sucking pests in cotton — particularly Ingard cotton —causing considerable damage (see The Australian Cottongrower July–August 2001, p.6). This is mainly due to the marked reduction in the use of non-selective Helicoverpa insecticides which previously also coincidentally controlled mirids.

Further reduction in the use of broad-spectrum insecticides is expected with two-gene cotton (Bollgard II), increasing the chance that mirids will be more of a problem.

Over this past cotton season, two or three insecticide sprays were required to manage mirids in some valleys, including the South Burnett. Most of the registered mirid chemicals are non-selective and are highly disruptive to a wide range of beneficial species. Use of these disruptive chemicals will minimise the potential value of IPM approaches.

Low rates of existing chemicals have been used to reduce their disruptive effect, but they do not always control the pests.