Tuesday 14 March 9.00 am – 11.00 am
FAR field site, North West corner of Springs and Ellesmere Junction Roads, Lincoln Google map. Access off Springs Road, 300 m north of Roundabout.
Join FAR, Potatoes NZ, and the BHU Future Farming Centre for a roundup of results to date on the use of mesh crop covers for potato pest & disease control and the findings from the current field trial.
- How mesh covers are controlling blight
- Mesh and tomato potato psyllid TPP control
- Aphids and mesh
- Potential yield boost from mesh due to improved microclimate
Get reports from the first two years trials here
Tomato potato psyllid (TPP) (Bactericera cockerelli) arrived in New Zealand in 2006 and has proved to be a important pest in a number of solanaceae crops, including potatoes. While insecticides have proved effective for its management, this has caused a large increase in agrichemical use which is undesirable, and this option is not available to organic growers. A ‘non-chemical’ means of controlling TPP is therefore desirable. Mesh crop covers are such a non-chemical control: they are akin to fly screen for crops. They are extensively used in Europe for controlling a wide range of pests on an equally wide range of crops by both organic and mainstream growers.
Prior research by the FFC made the serendipitous discovery that mesh crop covers are not only an effective barrier to TPP but they are also achieving significant potato blight (Phytophthora infestans and/or Alternaria solani) control. A correlation has been shown between a reduction in UV a & b light levels and blight and also TPP symptoms.
As mesh can keep out a wide range of potato insect pests, including those that are resistant to insecticides, such as tuber moth, it has the potential to be a single non-chemical solution to both insect pests and blight on potatoes. As potatoes are the 4th most important food crop globally, with more grown in the developing world than the developed world, the potential global impact in terms of reduced agrichemical use is considerable.
However, potato aphids, mostly Myzus persicae, are penetrating the mesh, even mesh that has sufficiently small holes to exclude winged (and wingless) adults. Once inside the mesh, their populations can explode due to the absence of beneficial insects, in effect, it is an unintentional experiment on the level of biological control of aphids.
Mesh with sufficiently small holes to exclude immature aphid instars has been tested and resulted in a second serendipitous that the fine mesh appears to be modifying the under mesh micro-climate resulting in increased yields, while also improving blight control.
Such very fine mesh has the potential therefore to completely control all potato insect pests, as well as blight and increase yield through entirely physical means.
The field day will provide an opportunity to hear more about the research as well as viewing mesh on potatoes.