Amistar, available from Syngenta , contains azoxystrobin, a member of the strobilurin class of fungicides (Group K), which has an ideal mode of action that inhibits mitochondrial respiration of fungi.
Azoxystrobin demonstrates good uptake and redistribution properties within the plant.
The active ingredient is steadily absorbed into the leaf, ensuring some active ingredient remains on the leaf surface to combat infection by incoming fungal spores.
Uptake can be enhanced if the foliar surface is rewetted, for example, following dew or rainfall.
Once absorbed, azoxystrobin diffuses through the leaf to reach the vascular tissue and is then acropetally transported within the leaf through the xylem.
This results in an even distribution of the active ingredient throughout the leaf and thus, protection from fungal pathogens. Azoxystrobin also demonstrates some translaminar activity.
Key fungal diseases
Stem End Rot (Dothiorella spp. and Lasiodiplodia theobromae) and Anthracnose (Colletotrichum gloeosporioides) cause serious post-harvest fruit losses in mangoes.
Australian field trials have confirmed that fungicide programmes incorporating Amistar provide good control of Stem End Rot and Anthracnose compared with standard programmes. In most cases, the use of Amistar will result in higher levels of marketable fruit.
Australian research also confirmed that Amistar significantly improves pack-out performance in mangoes. This trial was conducted in 2002 in a crop of Kensington Pride mangoes in Mareeba, Queensland.
The Amistar programme consisted of Dithane, then Octave, then Amistar (80 mL/100L) at early fruit set, then Kocide (200 g/100 L) and then two applications of Amistar (80 mL/100L) before harvest.
- Stem End Rot: 40g/100L
- Anthracnose: 40g/100L
- Refer to label for specific application situations
Thorough coverage of all foliage is essential. Apply the same total amount of product to the target crop, whether applying by dilute or concentrate spraying methods.
For good results, apply one to two applications of Amistar at flowering and early fruit set, at no less than 14 day intervals. Follow with applications of an approved fungicide from a different chemical group.
Further applications of Amistar may be applied at 14 to 28 day intervals, finishing no later than 3 days before harvest.
- Disease control may be reduced, if strains of pathogens less sensitive to Amistar develop
- Do not start the disease control programme with Amistar
- Do not use Amistar curatively
- Do not apply more than two consecutive applications of Amistar
- Consecutive applications of Amistar must be followed by at least the same number of applications of a fungicide with a different mode of action, before Amistar is used again in either the current or following season
- Do not apply more than three applications of Amistar in any crop during one season