Current Potato Research Projects
Ongoing Research Investment Streams
Potato Research Projects
In 2014 a project compared the influence of current seed treatment practices, current products at higher rates, some new fungicide products and a biological product to control seed and soil borne diseases. Assessments included impact on disease incidence, yield (tuber and DM) quality and carry over inoculum in the soil.
In 2015, a soil borne disease trial has been established in South Canterbury to evaluate the efficacy of various different fungicides either applied to the seed or in furrow. We are looking at old chemistry and new SDHI chemistry for the control of mostly rhizoctonia and powdery scab. Low disease pressure last season at the two trial sites made it hard to interpret results. A tight potato rotation at the site should result in high disease pressure and some interesting results.
Psyllid work will continue with trials established in Matamata, Manawatu and Canterbury. The incidence, importance and timing of pests varies markedly between potato growing regions in New Zealand.
The aim of the three field trials is to develop regionally focused pest management strategies, initially focussing on tomato potato psyllid (TPP) and zebra chip disease, putatively caused by Candidatus Liberibacter solanacearum (CLso).
This project will focus on developing reduced insecticide management strategies by: using thresholds to commence a spray programme (psyllid-count based or Degree Days) and incorporation of agricultural oils into a spray programme to protect the crop from insect pests and consequently from being infected with CLso (TPP) or viruses (aphids).
FAR were successful with an application to MPI SFF. The project will run for three years in Pukekohe, Manawatu and Canterbury and focus on ‘Increasing potato yield through understanding the impact of crop rotations and soil compaction”.
Year 1 is well underway with eighteen commercial potato field crops being evaluated for this season. The desired outcome of the project is to better understand where potatoes fit in the rotation, how to reduce soil compaction and improve soil structure whilst understanding how all these factors impact of soil borne diseases. Comprehensively testing abiotic and biotic factors along with understanding the rotation and soil borne diseases over three years will give us the full spectrum of how and where potatoes fit best along with understanding where we can increase yield.
The yield of potato is constrained by available root volume. Effective irrigation may help increase crop yield especially if there are soil constraints such as compaction. Effective irrigation is based on ET and soil moisture. For potatoes it is not clear how yield changes if irrigation is not managed effectively.
The 2014 trial evaluated a range of irrigation treatments which may mimic commercial field applications to determine the need for effective irrigation practices in potatoes and the yield loss growers may expect, this work was done only in Canterbury.
The 2014-15 trial results and report can be found here.
Investigating the water use efficiency of potatoes will be looked at again in 2015, only in Canterbury. A shallow stony soil will allow us to understand the water use on a different soil type. Treatments replacing various soil moisture deficit volumes will identify when we see a yield loss from water stress also identify where savings can be made through over watering and drainage events. Different stress timings will also be looked at. Often a decision needs to be made between watering one high value crop and another so better understanding when these timings will severely reduce potato yield are important.