Environment-friendly tools for lettuce growers
Lettuce growers have a number of practical new tools at their disposal thanks to a large science programme that has
developed a system of Integrated Pest Management (IPM) specifically for the outdoor lettuce crops grown in New Zealand.
Under IPM systems growers monitor crops regularly and manage pests and diseases in a manner which is sensitive to the
environment by encouraging predators and other biological control agents. IPM is becoming increasingly popular worldwide
as certain pests and diseases become resistant to chemicals that have been used on crops for numerous years.
This week, outdoor lettuce growers in New Zealand will each be mailed a wallet containing a glove-box sized guide and
CDROM, which will assist them to implement the new IPM programme.
Project leader, Stuart Davis, general manager operations at LeaderBrand Produce, says the project is a good example of
how the industry can come together to work on common problems.
“It has also been very encouraging to have the MAF Sustainable Farming Fund come on board to help with the development
of the tools and particularly the implementation stage where they were tested and demonstrated to growers in commercial
crops,” Dr Davis says.
“We’ve tried to make the wallet a one-stop shop. The IPM tools within the wallet provide a comprehensive approach to
identifying and managing both pests and diseases in the field.”
Crop & Food Research Entomologist Graham Walker says he is looking forward to the lettuce growers following the lead of NZ
outdoor processing tomato growers and brassica growers, who already implement IPM programmes designed for their
respective industries.
“We know IPM works and it is going to be the answer for an industry determined to meet consumer demand for sustainable
produce,” says Mr Walker. “The IPM regime will ensure their crops can meet increasingly stringent market standards.”
Mr Walker says the new system will still allow for the effective control of diseases and pests with the use of selective
pesticides but only when pest numbers exceed thresholds.
“The glove-box guide will assist growers to get to know the beneficial organisms that live in their crop including
predator insects such as the brown lacewing, tiny parasitic wasps, the eleven-spotted ladybird and many others.”
Below are features of an IPM programme
• Effective pest and disease control
• Production of crops that meet market standards
• Use of techniques that emphasise monitoring in some form
• Reduction of pesticide risks
• Use of selective pesticides in preference to broad spectrum materials
• Minimal impacts on the environment
Mr Walker says a key message of the programme is the need to monitor. “There is only one secret to getting an IPM regime
working well and that is the need to put your boots on and scout the crop. In this way you will get to know if you have
enough beneficial insects or too many problem insects. Once you know this, you can make a decision to spray or not to
spray and most importantly, what to spray with.”
For more information about the IPM lettuce programme please can contact Horticulture New Zealand or Crop & Food Research. The project was sponsored by the Sustainable Farming Fund and industry, including Horticulture New
Zealand, agrichemical companies and nursery companies.
ENDS