No silver bullet for PSA

Greg Walker of Wormtech NZ Ltd today advised kiwifruit growers to be cautious about suggestions circulating in the industry that its products are a cure for PSA.

“We have customers around the Bay of Plenty, including in the priority zone, who have expressed the view to other growers that while they can’t be sure, they may be PSA free in part because they are using our products” said Greg.  “Obviously we would love to be able to back that up with proof, but at this stage we have none.  Once the current field trials being undertaken by KVH produce results, we’ll all know more.  Until then, be very wary of anyone telling you their product is the answer.

“We have never made unsubstantiated claims about our products and we certainly are not about to start now.  We are concerned that with high anxiety among growers, some may be looking for a silver bullet, but our advice is to continue to follow the guidelines from KVH and Zespri.”

Wormtech NZ Ltd was established in 2000 to produce natural soil conditioners and foliar feeds derived from aged vermicast, as well as live worm, at its vermiculture operation near Whakatane.  Wormtech’s main products, Wormtech Ground and Wormtech Canopy, are sold to the horticulture and viticulture industries for application by foliar spray, ground spray, fertigation and ground probe injection.

Vermicast contains a wide range of microbes (fungi and bacteria) from the gut of the worm, which aid the biological health of the soil.  This provides part of nature’s defence against fungal and bacterial diseases as well as aiding breakdown of nutrients in the soil to allow uptake by plants.

“Clearly there are large quantities of copper being applied on many orchards in line with the current guidelines” said Greg.  “This will inevitably have implications for soil health which may expose growers to other vine health problems over time.  We are encouraging customers to take measures to restore soil microbial health after these sprays to mitigate this.  If in the process they get some extra PSA protection, that will be a bonus.”