CROP PROTECTION
Biostimulants Psa-V management with Actigard™ post-harvest The period between harvest and leaf-fall is a high risk for Psa-V in kiwifruit, with cooler and wetter weather favouring Psa-V infection in the autumn. Wounds created at harvest provide ideal entry points for Psa-V and late season growth (especially in male vines) is particularly vulnerable to Psa-V. The application of approved protectant sprays is recommended immediately post-harvest to help protect fruit stalks, leaves and late season growth from Psa-V infection. This includes copper, with the addition of Actigard where there is no risk of spray drift onto fruit. The benefit of applying Actigard early post-harvest is that leaves are in better condition to absorb the systemic active ingredient (acibenzolars-methyl), to provide up to 21 days protection. It can take 4 to 7 days for Actigard to fully activate kiwifruit vines, so the addition of copper is recommended for immediate protection and also for multiple modes of action against Psa-V.
To avoid the risk of residues when applying Actigard post-harvest, extreme care must be taken to avoid spray drift onto fruit in unharvested areas of the orchard or neighbouring orchards. Sprayer tanks must also be cleaned thoroughly before any other products are applied to unharvested vines. The precise mode of action of Actigard on Psa-V is not fully understood. However, Actigard has consistently shown to reduce the symptoms of Psa-V by stimulating the natural self-defence system of kiwifruit via a response known as Systemic Acquired Resistance (SAR). Trials in kiwifruit have shown that reducing the level of Psa-V infection in the autumn can help to reduce the symptoms of Psa-V in the following spring. For more advice on the use of Actigard for Psa-V management, contact your Farmlands Technical Advisor.
Actigard should be applied at a rate of 200g/ha as a dilute spray in conjunction with copper as soon as practical after harvest, with good coverage of leaves, fruit stalks and leaf scars required to optimise efficacy. Actigard can be applied to kiwifruit up to four times per season. Depending on how many Actigard sprays have been applied previously, up to two applications of Actigard can be applied at 21 day intervals post-harvest if canopy condition allows (i.e. leaves are still green). Actigard is likely to be less effective when applied to leaves at an advanced stage of deterioration or after a significant frost event. Growers should avoid applying Actigard to vines already stressed due to frost, high winds or excessive moisture. This means applying Actigard prior to, rather than after, high risk weather events. Article supplied by Syngenta Crop Protection.
Actigard
Fylloton
500KG ACIBENZOLAR-S-METHYL
• Fylloton promotes the synthesis of proteins and natural growth substances. It is rich in tryptophan, the precursor of auxins, which stimulate plant vegetative growth. By promoting plant energy savings and metabolic activity, the result allows plants to keep growing in environmental stress conditions and to overcome growth arrests due to agrochemical application.
• Stimulates the plant’s natural selfdefense against Psa in kiwifruit. • Can be applied pre-blossom and post-harvest at 21 day intervals. • Systemic activity offers rainfast protection for up to 21 days.
5L: 187525 20L: 187526
1kg: 165992
Folicist • Folicist® works during flowering and fruit set, where high amounts of energy, proteins, sugars, nucleic acids and phytohormones are required to sustain cell division. • Folicist® optimises flowering and fruit set by acting as both a growth-promoting and anti-stress agent. 1L: 186475
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Farmlands Horticulture PRODUCTGUIDE
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