PGG Wrightson joins A Lighter Touch

PGG Wrightson has joined the A Lighter Touch programme as its first merchant partner to support growers in moving to more sustainable crop protection practices.

A Lighter Touch (ALT) is a $27 million, seven-year, programme jointly funded by government and industry. The focus is to find tools to support the horticulture, arable and viticulture sectors to move away from agrichemical reliance and towards a more agroecological approach.

PGW’s support helps ensure research and tools created by the programme are shared with farmers and orchardists throughout its networks. PGW technical advisors also contribute advice and input to ALT projects.

A project run by A Lighter Touch (ALT) and NZ Buttercup Squash Council seeks to develop an agroecological “whole of farm” approach to managing soilborne diseases in buttercup squash crops, which cause average annual losses of around 30 percent, and cost growers of this mainly export crop an average of $20 million a year in lost revenue.

ALT Agroecological Technical Lead Jeff Smith says, “Soilborne diseases are a problem for a wide range of crops besides squash, from passionfruit through to arable and other vegetable crops, so findings from this project will be of interest to many other growers.”

Now, in the second season of the five-year project, demonstration sites in Hawke’s Bay and Gisborne are being developed to compare an ALT approach to typical practice. This follows a review, led by Lincoln University, of all New Zealand and overseas knowledge on the prevalence, management and mitigation of soilborne diseases in squash and related cucurbit crops, including plant breeding for disease tolerance. The aim was to establish what growing practices could be integrated into the NZ buttercup squash programme to mitigate or break the soilborne disease cycle.

Jeff says that the knowledge review and other project activities will be used to develop a Best Management Practice (BMP) Guide for growers. “Initial findings from the knowledge review and a BMP grower workshop will ensure grower input feeds into the guide. The demonstration sites will involve growing squash using the learnings from the knowledge review and grower BMP workshop. Having the same conditions for both management approaches is important to ensure a comparable control.”

The Cromwell orchard biodiversity project run by A Lighter Touch and Summerfruit New Zealand aims to understand how to integrate understory plantings into summerfruit orchard systems to determine whether benefits can be demonstrated. These may include less mowing, reduced herbicide applications, improvements in soil health, and enhanced natural enemy populations resulting in reduced pest pressure.

Understory plantings were established in two Central Otago stonefruit orchards two years ago, with another planted last autumn. The understory includes plants such as phacelia, alyssum, coriander, clovers, and plantain to provide good quality nectar and pollen as food sources for the adult stages of many beneficial insects such as parasitoid wasps, hoverflies, and lacewings.

ALT Agroecological Technical Lead Jeff Smith says the first year’s results saw a higher abundance of beneficial insects and reduced application of herbicides.

“Monitoring by Plant and Food Research showed greater diversity of flowers in the orchard due to the understory planting, which resulted in higher numbers of insects in the understory blocks than in other parts of the orchard. 

The lush growth of the plantings also provides a sheltered environment for the insects.

“Over this first season of the project the growers involved were able to significantly reduce maintenance inputs such as mowing and herbicide spraying in the understory blocks, compared to the standard orchard practice.”