The Farmers Gazette

Caterpillars For sweet and baby corn the most important caterpillar is cob worm or Helicoverpa armigera. Unfortunately the sheath and cob itself are poor conductors of systemic chemicals. It is therefore necessary to add a product with high vapour action to the products chosen below. Dichlorvos at 100 ml/100 litres of spray mix does an excellent job as a synergist because of its high vapour action. Various caterpillars attack the crop. These include loopers, army worm etc. Spray as required in 250 l/ha water with one of the following. ACTIVE INGREDIENT TRADE NAMES acephate α-cypermethrin β-cyﬂuthrin Bacillus thuringiensis chlorpyrifos cypermethrin deltamethrin dichlorvos endosulfan indoxacarb -cyhalothrin malathion ORTHENE® FASTAC® BULLDOCK® DIPEL®, BIOBIT® DURSBAN®, PYRINEX® CYMBUSH®, RIPCORD® DECIS® DDVP®, NOGOS® THIODAN SC® STEWARD® KARATE® MALATHION 25 WP MALATHION 50EC TAMARON® LANNATE SL®,METHOMEX® DIPTEREX 95SP® methamidophos methomyl trichlorfon RATE/100 L WATER 200 7 17.5 200 100 10 20 100 200 35 8 500 250 100 225 150 g ml ml g ml ml ml ml ml g ml g ml ml ml g 15 L KNAPSACK 30.0 1.0 2.6 30.0 15.0 1.5 3.0 15.0 30.0 5.2 1.2 75.0 37.5 15.0 33.7 22.5 g ml ml g ml ml ml ml ml g ml g ml ml ml g RATE/HA 500 17.5 43.75 500 250 25 50 250 500 87.5 20 1250 625 250 562.5 375 g ml ml g ml ml ml ml ml g ml g ml ml ml g Note that methomyl also has very good vapour action but this should only be applied either by air or through an insectigator on a centre pivot. It is a very dangerous chemical to apply in a standing maize crop. 16 FARMERS GAZETTE November 2015

The Farmers Gazette | Page 18