The principal objective for Integrated Pest Management (IPM) systems is to reduce the amount of hard (broad-spectrum) chemicals needed to control insect pests in crops. Part of the strategy to achieve this objective is to use highly selective biological pesticides in place of hard chemicals wherever possible. Unfortunately, many good biological pesticides are very quickly rendered less effective by their susceptibility to degradation by the sun’s rays.

This project looked at developing a sunscreen based on titanium dioxide that would protect biological pesticides from UV degradation, thus enabling existing biological pesticides to be used more effectively and make others that are non-viable become viable.

A tank mix additive has been developed that can be used with both biological and hard chemical pesticides. Thus, it has the potential to render biological actives more effective as well as reduce the amount of any UV susceptible hard chemical pesticide required to achieve a given result.

The product tank mixes well over a pH range from 4 to 10, thus covering most conditions likely to be encountered in Australia. Moreover, the mixing qualities are unlikely to be adversely affected by formulation additives used in other tank mix components.

In laboratory trails by IPM Technologies Pty Ltd, with 2nd instar Plutella xylostella larvae on cabbage leaves, the formulation was shown to provide protection for Bacillus thuringiensis insecticide against UV degradation down to 0.1% on spray water. Also in laboratory trials, the formulation, when used at 1.0% on spray water, was shown not to deter the feeding of 2nd instar P. xylostewlla, where the product was shown to yield markedly superior performance against first and second instar larvae.

Experiments conducted on the Eureka AgResearch rainfall simulator showed that the product was also very effective as a sticker to enhance rainfastness.

Successful commercialistation of this product will allow growers to expect improved performance from soft pesticide options and reductions in the application rates for UV susceptible hard chemical pesticides.