Reports


Tomato/Potato Psyllid (TPP) on Capsicums – Report 2018

Quantifying the risk of tomato/potato psyllid (TPP) eggs, nymphs or adults on capsicum fruit based on leaf infestation levels -The presence of tomato/potato psyllid (TPP; Bactericera cockerelli) on export capsicum fruit can cause market access issues resulting in costly methyl bromide fumigation, which can significantly reduce out-turn quality of capsicums.  Read more here.

 

Potato & Tomato Psyllid monitoring

Regular monitoring for the tomato / potato psyllid is essential for effective control.  Two types of monitoring can be carried out.  Placement of yellow sticky traps indicate when adults are prevalent in the area, but not enough is yet known to establish control thresholds.  The other options is inspecting plants (particularly the lower 1/3 of stems and leaves) which gives valuable information on the numbers and life stages present in the crop, and can be used to direct to types of control products to be used. 

It is also useful to monitor (or preferably remove) alternative hosts which include the common weeds dandelion, amaranth, convolulus, jimson weed, mallow, and black nightshade. Ornamental solanaceous plants are also potential hosts, and so is the native plant poroporo.

Psyllid monitoring is now being carried out at sites across New Zealand as part of the Sustainable Psyllid Management SFF project.  This data, along with the latest information on psyllid monitoring, is available on the Potatoes New Zealand website.


Candidatus Liberibacter and the Potato & Tomato Psyllid

MPI Biosecurity NZ temporarily withdrew its phytosanitary certification for the export of tomatoes and capsicums on Tuesday 3 June 2008. We are of the opinion that the application of a prohibition or other phytosanitary measures to tomato and capsicum fruit is not the best approach to take. This opinion is based on an evaluation of the likelihood of the new Liberibacter being introduced into another country through trade in tomato and capsicum fruit. Although little is known about the Liberibacter in tomatoes and capsicums, much can be drawn from the biology of other members of this genus, and the application of phytosanitary principles.

The new potato & tomato psyllid code of practice can be downloaded here, and grower guide can be downloaded here. The results of the latest research into Liberibacter can be found on this website's members only page for research reports, which can be found here. Emergency measures for market access into Australia for tomatoes and capsicums are detailed here, and the temporary phytosanitary compliance programme for the export of capsicum and tomato fruit to Australia can be downloaded here.

  • Click here to download a 8 December 2008 update on Candidatus Liberibacter from MAFBNZ.
  • Click here to download a 7 November 2008 update on Candidatus Liberibacter from MAFBNZ.
  • Click here to download a 26 October 2008 update on Candidatus Liberibacter from Horticulture New Zealand.
  • Click here to download a 25 August 2008 update on Candidatus Liberibacter from Horticulture New Zealand.
  • Click here to download a 22 August 2008 update on Candidatus Liberibacter from MAFBNZ.
  • Click here to download a 25 July 2008 update on Candidatus Liberibacter from Horticulture New Zealand.
  • Click here to download a 24 July 2008 update on Candidatus Liberibacter from MAFBNZ.
  • Click here to download an 11 July 2008 update on Candidatus Liberibacter from MAFBNZ.
  • Click here to download a 3 July 2008 update on Candidatus Liberibacter from MAFBNZ.
  • Click here to download a 26 June 2008 update on Candidatus Liberibacter from Horticulture New Zealand.
  • Click here to download a 24 June 2008 update on Candidatus Liberibacter from MAFBNZ.
  • Click here to download a 20 June 2008 report from MAFBNZ summarizing the process followed to diagnose this disease.
  • Click here to download a 3 June 2008 letter to growers from Horticulture New Zealand.

The potato & tomato psyllid (Bactericera cockerelli) was originally found in 2006 on tomatoes and potatoes in the Auckland and Waikato regions. Adults look like tiny cicadas, 2 - 3 mm long. It is a serious pest of potatoes and tomatoes, as well as capsicum and other solanaceous crops and difficult to control. In 2007 the psyllid spread south and was also found in Nelson. In 2008 it was also found in outdoor tomato crops in the Hawkes Bay and Gisborne, but its ultimate range may be limited to areas with winter temperatures above 0ºC.  A fact sheet on the psyllid was published by Plant & Food Research in March 2009, and can be downloaded by clicking here.

Please click here to download a poster with information on this pest, click here to download some fact cards, or click here to view MPI's information on this species.


Resource Inventory and Carbon Footprint for Greenhouse Tomatoes and Capsicums

MPI SFF and FTPG Project: L07/026 (funded by MAF's Sustainable Farming Fund & the Fresh Tomato Product Group.

The carbon footprint of greenhouse produced vegetables; e.g. tomatoes and capsicums to the "farm gate" is larger than any other horticultural crop, although the profiles are likely to start converging when the system boundary is extended to include postharvest emissions. 

Where greenhouse production has large emissions due to heating, as the fruit is picked and consumed within a couple of weeks they have a small refrigeration requirement and negligible losses.  Other fruit that can be stored for long periods of time and slowly released onto the market while having lower production emissions have an ever increasing postharvest carbon footprint.
 
Although this project has established a carbon footprint for NZ greenhouse tomatoes and capsicums it is largely a meaningless number.  Even when compared to the carbon footprint of other food it is only one aspect (if the information is available) that consumers may consider when making their purchasing decision. For example it is doubtful that a customer is going to choose an onion over a greenhouse tomato because the latter has a higher carbon footprint. 

Of more importance than the carbon number itself, is how that number is being lowered.  Greenhouse heating dominates the carbon footprint, so consequently the priority for improvements should focus in this area.  Not surprisingly due to the increasing energy costs and some quick payback opportunities for improvement, the industry already has a number of initiatives in place to ensure greenhouse heating and profitability is improved.


 

Determination of pre harvest intervals for a range of insecticides in salad leaf crops

August 2014: This report summarises a salad leaf pre harvest interval (PHI) trial conducted in Gisborne during February and March 2014 on five varieties of salad leaf.  Click here to download the report

Buried Weed Seed Longevity: Interim Results for Years 1-4

January 2014: This study was conducted to determine the "decay" rates of seven annual grass weeds.  Click here to download the report.

Great White Butterfly

November 2014: Great White Butterfly Report Update

Click here to download the report.

Drip Irrigation SFF 12 109 - Final Report

April 2013: This booklet provides case studies and technical information about the use of drip irrigation for vegetable production in New Zealand. The technology is used in many countries with considerable advantage, but is not widely adopted in New Zealand. In 2012, Vegetables NZ and Irrigation NZ sought to identify key issues showing wider adoption of this internationally proven technology. Understanding these barriers forms a critical component of on-going industry efforts to increase water and nutrient use efficiency in cropping systems.

Click here to download the report

Diamondback Moth in New Zealand  “An integrated pest management (IPM) program for vegetable brassicas”   

April 2012: Final report for the management of diamondback moth (DBM), Plutella xylostella, in New Zealand include reassessment of the status of insecticide resistance, and updating the insecticide resistance management rotation strategy for DBM within the context of a revised integrated pest management (IPM) program for vegetable brassicas.

Click here to download the report

Carrot Violet Root Rot

July 2010: Violet root rot (VRR) is a serious fungal disease of carrots and potatoes, and threatens the long term viability of the vegetable industry in the Ohakune district. Previous attempts at control have been largely unsuccessful. This report summarises the third year of a three-year programme to evaluate the potential of commercial fumigants to control VRR.

Click here to download the report

Hedging our bets: choosing hedgerow plans to enhance beneficial insects to optimise crop pollination and pest management on Canterbury farms

June 2010: A desk-top study which examines the associations between plants, insect herbivores, their natural enemies and pollinators to evaluate the potential of using perennial plant assemblages on non-productive areas of a farm to maximise the establishment and abundance of beneficial insects. Pollination and pest suppression are key on-farm services provided by beneficial insects (pollinators, predators, and parasitoids). Yet the potential of beneficial insects to provide these essential services is often not realised because they are absent or low in numbers, generally due to historical management practices.

Click here to download the report

Treatment of hydroponic wastewater using a denitrification filter system

June 2009: Nitrogen and phosphorous removal from wastewater of a hydroponic greenhouse operation was investigated over the summer of 2009.  This study aimed to investigate whether adequate removal of these nutrients could be achieved, determine the key operating parameters, and establish a general design of a denitrification filter system. 

Click here to download the report.


Integrating energy efficiency and pest management of vegetable covered crops

Update 28 March 2009: MAF SFF/ Fresh Vegetable & Fresh Tomato Product Groups funded project in its third and final year of work.  A major achievement in this reporting period (to end March 2009) has been the successful importation into containment of Tamarixia trizoae.  The colony has established and has shown good parasitism rates.  Progress in other areas continues to be hampered by the distraction of psyllid and Liberibacter which remains a major concern for industry and is occupying a significant proportion of our key researcher's time.  The project is indirectly assisting these activities by providing a working group for discussing responses to the issue and disseminating information.  For these reasons the project is behind on some milestones and the budget is under spent. 

Click here to download the 28 March 2009 progress report.


Graft transmission and seed transmission of Liberibacter

Summary: Research conducted by MAF suggests that the Liberibacter species which has been identified in New Zealand solanaceous crops is not transmitted by seed, but is graft transmissible. 

Click here to download the report on seed transmission, or click here to download the report on graft transmission.


The Carbon Footprint of New Zealand

Summary: There is growing public concern that carbon dioxide emissions are having a significant detrimental impact on the environment. In particular this has been brought to consumer's attention by various 'Food Miles' campaigns, a constant stream of climate change stories in the media and a desire by some UK supermarkets to label the carbon content of food. The NZ greenhouse tomato and capsicum industries are a mix of domestic and export market producers and have the potential, as producers of high quality high value products, to be directly affected by Food Miles and carbon footprinting requirements. Accurately determining the NZ greenhouse tomato and capsicum carbon footprints and then gaining insights into how it can be lowered is seen as essential for continued trade.

Click here to download this report.


Management Strategies for Kumara Black Rot

Summary: The kumara disease known as black rot is caused by the fungus Ceratocystis fimbriata. In recent years the black rot disease has been found more frequently. As this pathogen is highly transmittable and can cause severe economic losses within production beds, fields and storage, the disease and management strategies are described.

Click here to download this broadsheet.


Strategic Agrichemical Review Process 2007 final reports

Summary: These reports were funded by Horticulture New Zealand to investigate the pest problem, agrichemical usage, and pest management alternatives for industry groups across New Zealand. The information in these reports will assist the industries with their agrichemical selection and usage into the future.

Six SARP reports are available - brassicascarrotscucurbitskumaralettuce, and peppers.


Greenhouse Nutrient Solution

Summary: The Greenhouse Nutrient Solution project is to assist growers with the practical, sustainable and legal management of discharging greenhouse nutrient solution. All greenhouses with crops grown in soilless media will at some stage need to discharge or release excess nutrient solution. As the solution will contain nitrogen there will be the potential that the solution could contaminate water bodies. This Guide sets out what a grower needs to do to ensure that pollution does not occur when irrigating discharged nutrient solution.

Three documents are available - a Guide, a Code of Practice, and a Calculator Model. To download "A Guide to Managing Greenhouse Nutrient Discharges" click here, to download the "Code of Practice for the Management of Greenhouse Nutrient Discharges" click here, and to download the "Greenhouse Nutrient Discharges Calculator Model" click here.


Advancing integrated pest and disease management (IPM) for vegetable brassicas

Summary: The vegetable brassica industry initiated a project to update IPM for vegetable brassicas, by revising Integrated Pest Management for Vegetable Brassicas (the IPM Manual). The project objectives were to update the status of insecticide resistance in diamondback moth in New Zealand, incorporate newly registered products into the insecticide resistance management rotation strategy, and update the disease and other relevant sections in the IPM Manual.

To download a PDF of the full report click here.


Nutritional attributes of spinach, silver beet and egg plant

Summary: This report focuses on the nutritional attributes of spinach, silver beet and egg plant. The composition of these vegetables is described and related to their beneficial effects on health. Factors that may influence the nutritional profile of these vegetables and consequently their health benefits are also explored. Some quirky quotes and trivia about these vegetables are also included.

To download a PDF of the full report click here.


IPM Lettuce Final Report SFF 15 059 - 1999

Sept 2007: The Leafy Crops Advisory Group (Vegetables NZ) initiated a two-year implementation phase to transfer technology eveloped from the previous“IPM for Outdoor Lettuce” SFF project to growers and crop scouts/consultants.  The project team included key growers and industry personnel from the major lettuce-producing regions, Pukekohe, Gisborne and Horowhenua. The project work focused on crop scout training for different regions, replicated field trials, continued monitoring of small insect pests, development of action thresholds for the major insect pests (particularly caterpillar pests) and the dissemination of results in the IPM manual/guide.

 To download a PDF of the full report click here

Contributions to an understanding of sweetpotato brown centre disorder

Summary: Sometimes the interior of Owairaka Red kumara roots becomes brown and inedible due to cell death, a condition known as brown centre. Experiments conducted during the 2006/2007 growing season tested the hypothesis that brown centre is caused by excessive canopy growth and a decreasing rate of photosynthesis. When the size of the canopy is limited by other constraints, the addition of nitrogen seems to maintain the canopy's effectiveness. This reduces the need for carbohydrate remobilization from the root, so decreasing the occurrence of kumara brown centre. The association of contributing factors – particularly the relationship between sunshine hours and the time of brown centre onset is still to be proven.

To download a PDF of the full report click here.


Research Summaries

As research reports and summaries become available they will be added to this page. Keep an eye on the news section of the home page for updates.

A list of fresh vegetable research reports funded between 1994 - 2008 can be found here.