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FORMULATION & ACTIVE INGREDIENT: CALLISTO is a suspension concentrate containing 100 g/l (9.1% w/w) mesotrione

TARGETS: Selective control of annual broad-leaved weeds in forage and grain maize.


CALLISTO contains mesotrione a foliar applied herbicide for selective control of annual broad-leaved weeds. The activity of CALLISTO is mostly by foliar uptake and to some extent by soil uptake. CALLISTO is rapidly absorbed through the leaves and moves to the growing point.

For use only as a herbicide for the control of weeds in forage maize and grain maize. DO NOT USE on forage maize and grain maize seed crops or on sweetcorn varieties.

Spray Timing
Always inspect crop and weed growth stage immediately before spraying.
For best results treat young weed seedlings. See weed control tables for application details.

Forage maize and grain maize may be sprayed any time from the two to eight leaf stage.

For the best results CALLISTO should be applied when the weeds are actively growing i.e. in warm humid weather with adequate soil moisture. Treatment in poor growing conditions or in dry soil may give less reliable control.

Do not spray when weed or crop foliage is wet.

It is not recommended to spray crops suffering from stress e.g. when in very cold or drought conditions, or when wide temperature fluctuations are expected or excessive rainfall is expected to follow application. Under these adverse conditions mild to moderate chlorosis may be observed on sprayed leaves. This effect is usually transient and does not affect yield.

Take extreme care to avoid drift onto dicotyledonous plants outside the target area. Take extreme care to avoid drift onto all crops outside the target area, otherwise crop damage will result.

Ensure that spray swaths are matched accurately and do not overlap.

CALLISTO is a 4-HPPD inhibitor, disrupting development of plant pigments which are essential for photosynthesis. This inhibition causes leaf chlorosis and eventual death of sensitive weed species. It’s mode of action is different from other herbicide groups, and there is no known cross resistance in weeds which exhibit reduced sensitivity to other herbicides. Weed control may be reduced if strains of individual species less sensitive to CALLISTO develop.

The use of CALLISTO in programmes or tank mixtures with a broad-leaved weed herbicide possessing a different mode of action will reduce the likelihood of resistance developing in broad-leaved weeds e.g. Fat hen, Black nightshade, Common amaranth. At the present time there is no similar mode of action in herbicides for crops other than forage maize and grain maize and therefore crop rotation will also delay the onset of any resistance. Where continuous forage maize and grain maize are grown the use of CALLISTO for more than two seasons should be avoided.

Rate of use
CALLISTO contains an adjuvant system and the addition of an adjuvant or a tank mix wetting agent is not recommended.

The recommended dose rate is 0.75 to 1.5 litres per hectare depending on the type of weeds present and on their growth stage.

Good spray cover is essential and care should be taken to ensure that the sprayer has a matched set of nozzles, the machine is correctly calibrated and adjusted to the correct height above the crop.

Apply using a medium quality spray (BCPC) at a pressure of at least 2 bar.
Apply through conventional crop spraying equipment.

Preparation of the spray
Shake the CALLISTO container before opening.

Half-fill the spray tank with clean water, add the required amount of CALLISTO and agitate while filling the tank. On emptying the container, RINSE CONTAINER THOROUGHLY by using an integrated pressure rinsing device or manually rinsing three times. Add washings to sprayer at time of filling and dispose of container safely. Continue agitation during spraying.

Volume of water
Even cover of the weeds is essential.
Use 200 to 300 litres (maximum) of water per hectare. The lower rate is preferable, but the higher volume may be necessary where there are dense or well developed weed populations.

Application methods
Apply through a conventional field crop sprayer using a pressure of 2–3 bars. Ensure the sprayer is correctly calibrated before use.
Do not leave spray liquid in the sprayer for long periods (i.e. overnight).

After Use
It is important to wash equipment thoroughly after use to remove all traces of CALLISTO as even small amounts may cause damage to crops. Rinse inside of tank with clean water using at least one tenth of the spray tank volume. After flushing through pump and spray lines, drain and repeat procedure.
Disposal of spray tank washings should be in accordance with local, state or national legislation

Ploughing is recommended prior to reseeding. Some slight crop effects may be seen soon after emergence, but these are usually transitory in nature. Forage and grain maize can be re-seeded immediately in case of crop failure.

Rotational crops
Winter wheat (including durum wheat), winter barley and ryegrass can follow a forage maize and grain maize crop treated with CALLISTO.
Deep ploughing (greater than 15 cm) followed by cultivation is necessary before drilling oilseed rape.

Forage maize and grain maize, ryegrass, spring wheat and spring barley may be sown in the spring following application of CALLISTO, do not sow any other crop at this time.