Vegetables New Zealand

Research Projects

The Vegetables NZ Inc. R&D Committee has invested in the following projects:

Nitrogen Managers for Environmental Accountability - Current

Ministry for Primary Industries Sustainable Farming Fund (MPI SFF) project is designed to develop a system that will provide accountability with regard to nitrogen inputs and resulting nitrate leaching losses across a wide range of production scenarios. A technically robust tool designed to provide for the needs of both growers and regional councils will underpin this system. Resulting in a system that allows growers to demonstrate responsible use of nitrogen inputs, thereby satisfy Regional Councils that activities are consistent with the requirements of Regional Plans.

Vegetable Brassica IPM Manual

This is the Brassica Vegetable IPM Manual recently updated in February 2016. It is a pocket guide to pests, natural enemies, diseases and disorders of vegetable brassicas in New Zealand.

There are three versions of the IPM Manual.
High resolution for PC use.
Low and medium resolution for smartphone and tablet use.

New Zealand Code of Practice for the Management of Tomato/Potato Psyllid (TPP)in Greenhouse Capsicum and tomato Crops

The tomato/potato psyllid (TPP), Bactericera cockerelli is now a widespread pest in New Zealand (first confirmed present by Biosecurity NZ, May 2006) and is the vector for Candidatus Liberibacter solanacearum (Ca. L. solanacearum), a bacterium which causes a disease of capsicums, tomatoes and other Solanaceous crops including potatoes. 

Click here for the capsicum and tomato  industry’s Code of Practice pdf document that will assist in the management of TPP and the associated disease causing organism Ca. L. solanacearum.

A new approach to identifying La France disease (1996) F000975797

This project set out to establish the reverse transcriptase PCR (RT-PCR) method for the detection of La France disease in New Zealand mushroom caps. As a result of this study it is confirmed that the RT-PCR method is suitable for New Zealand conditions and that results are consistent and reliable. The conclusion from this work is that New Zealand mushroom growers should adopt this method because it is quicker, more sensitive and cheaper than existing methods. Click here.

Advancing integrated pest and disease management (IPM) for vegetable brassicas – final report (2007) F001435619

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 (DBM) 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. Click here

An Evaluation of Fungicides for control of Lettuce Ringspot (1995) F000975775

This report presents the results of recent trials to evaluate six fungicides (Captan; Chlorothalonil; Cupric hydroxide, Cyproconazole; Mancozeb; and Prochloraz) used to control lettuce ringspot under glasshouse and field conditions. Of the fungicides selected Captan, Cupric hydroxide, and Mancozeb are currently registered in NZ for use on lettuce and their effects are explained in the report. It is recommended that cultural practices also play an important part in the control of ringspot disease on lettuce. Click here

Assessing new biological control agents

The report "Assessing new biological control agents in greenhouse capsicums and tomatoes" by Peter Workman is now available - Click here

Assessment of insecticide resistance in diamondback moth (1997) F000946977

This study was prompted to determine if insecticide resistance was responsible for the failures to control diamondback moth (DBM) with insecticide applications. The levels of insecticide resistance in this study are considered to be currently reducing the sustainability of vegetable brassica growing. Click here

Assessment of seed tuber treatments of New Zealand yam (2001) F001426592 

In this study two field trials were carried out to test the effects of fungicide treatment of seed tubers on crop performance and soil borne diseases. It was found that the very mixed nature of the pathogen suite in New Zealand yam tubers makes the management of soil borne or tuber borne disease difficult. Control of the diseases may be best achieved by selection of healthy seed tubers, appropriate crop rotation, and possibly selection of varieties that are resistant to disease. Click here

Biennial Meeting of the National Vegetable Pathology Working Group, Adelaide Australia, 21-23 April 2004 (2004) F001435713

This report lists the HAL-funded vegetable pathology projects currently underway in Australia, and summarizes the key recommendations from the NVPWG meeting. The field trip and growers seminar associated with the meeting are also briefly outlined. Click here

Bitterness and cucurbitacin levels in New Zealand-grown zucchini cultivars (2003) A0018783

This study was carried out after reports were received from the New Zealand public that bitter-tasting zucchini were being produced by plants throughout the country. The bitter compounds tasted were not chemically identified as a result of this research but it is recommended that the identity of the bitter compounds is further investigated and any bitter fruit reported by consumers are obtained for analysis. Click here

Black rot and sweet potato weevil of kumara (1995) F000992159

It is understood that exports of fresh kumara to Japan and Australia are prohibited or can only be made under very stringent phytosanitary conditions, due to the belief by the Japanese that the sweet potato weevil, Cylas formicarius, is present in New Zealand although it has never been found. This document contains three reports: developing a protocol to export kumara to Australia; sweet potato weevil and exports of kumara to Japan; and sprouting inhibitors and export of kumara to Australia. Click here

Clubroot Control in Vegetable Brassicas Using Soil Incorporation of Fungicides (1998) F000947123

The objective of this study was to evaluate promising fungicides as a soil-incorporated or soil-drenched treatment for control of clubroot. All treatments were seen to give higher plant top weights than the untreated control. The soil-incorporation technique of fungicide application was found to be less labour-intensive than soil-drenching and also a time-saving and cost-effective technique. Click here

Clubroot Control with "safe" Chemicals (1998) F000947147

This report describes clubroot and the causative pathogens, summaries the latest information on controlling the disease, and reviews chemical control methods that are regarded as “safe”. This review has been undertaken to assist growers to develop effective, low-pesticide methods of clubroot control, and to provide background information to guide research on clubroot control. Click here

Clubroot of vegetable brassicas: a review (1994) F001319250

This report summaries relevant information on clubroot, and includes a brief outline of the disease, the causative organism, and methods that have been investigated for clubroot control. The research finds that the use of resistant cultivars probably offers the best prospect for effective and economic clubroot control and recommends that vegetable brassica growers should re-acquaint themselves with the available methods to alleviate clubroot, and take a fully integrated approach to control of the disease. Click here

Comprehensive pest list for New Zealand yam (Oca) (Oxalis tuberosa) (2001) A0019402

A 2 year study has been completed to firstly determine the pest and disease issues that are faced in this country by the yam industry, and then to develop practical pest and disease control solutions for growers. This comprehensive pests list summarises all the pest and disease problems that have been identified over a 2 year period. Our present understanding is that yam crops in New Zealand are largely free of viruses and have been that way for many years. Click here

Contribution to an understanding of sweetpotato brown centre disorder (2007) F001435633

This is the final report for a research project examining the psychological mechanism that give rise to the sweetpotato storage root disorder brown centre (BC). The hypothesis of best fit is that BC is caused by excessive canopy growth and a decreasing rate of photosynthesis, so that carbohydrate is remobilised from storage roots to maintain the canopy. This project indicates that in BC management the focus should be on the degree of crop canopy growth and canopy condition. Click here

Control & Identification of Root Knot Nematode (1998) F000947149

This report describes a field trial to evaluate the effect on yield of applying a nematocide to nematode-infested ground before planting a carrot crop. Their results found that these trials indicate that the use of nematocides has the potential to improve the percentage yield marketable carrots.  This report also discusses the successful use of PCR primers to identify the root knot nematode. Their results indicated that it is possible to apply PCR techniques to New Zealand populations to resolve questions about which species are present in New Zealand, and their distribution. Click here

Control of clubroot in vegetable brassicas (1995) A0019406

A programme of research has been undertaken to investigate the improved control of the disease clubroot. Control of clubroot in vegetable brassicas has been identified as an important priority for the fresh vegetable industry in New Zealand. This report outlines the progress of two research projects. The first project investigated the use of disease resistance to combat the disease in a field trial and in the second project, glasshouse trials were carried out to test the efficacy of a number of chemicals for clubroot control. Click here

Control of clubroot of vegetable brassicas (1997) F000946922

Clubroot is an increasingly severe problem for growers of vegetable brassicas in New Zealand. This report outlines progress in an on-going project that aims to develop integrated control of clubroot of vegetable brassicas. This study confirms that chemicals and disease resistance/ tolerance have potential as components of an integrated clubroot management strategy. Click here

Control of grass grub in New Zealand yam crops (2005) F001435819

Soil-borne insects are one of the most troublesome pests for growers of tuber crops. In this project three pesticides were applied at the second mounding of New Zealand yam in order to evaluate their efficacy for grass grub control. Unfortunately there was no response to pesticide treatment as grass grub presence was very low in the two blocks used. Click here

Control of Phytophthora root rot in Spinach (2005) B0005403

This report looks into the effects of three biological products, three cultural practices and RidomilG on Phytophthora root rot in spinach. On the basis of the results it was recommended that Superzyme (a biological product) or raised bed alone (a cultural practice) can be used to control Phytophthora root rot in spinach. Click here

Cucurbitacins in bitter Zucchini (2002) A0019404

Cucurbitacin is a biochemical compound found in some plants which result in a bitter taste. This report covers Cucurbitacins’ action/toxicity level/published levels in vegetables; levels of cucurbitacins detectable by taste v. toxicity levels; control of cucurbitacin synthesis: weather, pest pressure; species and strain difference in levels of cucurbitacins in vegetables; and looks into any special links to New Zealand. Click here

Diamondback moth pheromone trapping and pest scouting (2001) A0019411

Diamondback moth (DBM) is found throughout the world and is considered the most destructive insect pest of brassica crops. This report investigates the use of pheromone traps as a tool to forewarn growers or crop managers of periods when DBM larval numbers in their crops are likely to increase to economically damaging levels. Overall, the pheromone traps were useful tools for predicting larval infestations in most crops in spring and early summer. Click here

Dichlorvos EPA new controls update November 2015

A decision was made to retain use of Dichlorvos, but impose significant restrictions and additional controls to be phased in over the next five years. This document is provided for five Horticulture New Zealand product groups to explain how the controls imposed will impact use, as a result of the Dichlorvos reassessment. Click here

Enabling sea-freight of capsicums to Japan (2000)

Sea-freight of glasshouse-grown capsicums to Japan offers significant cost savings over conventional air-freight. This interim report describes progress to the end of a first season of a two-year project. This research is designed to deliver protocols for optimum capsicum storage during sea-freight. Their research findings have led to some general conclusions but large differences were found based on different districts and harvest times. Click here

Energy crop potential in vegetable rotations (2007) F001412425

The context for this review and analysis of research literature on energy crops include current challenges to profitable, sustainable vegetable growing, create interest in finding new crops that can fit into rotations; the strong market interest in energy crops sue to high fossil fuel prices and pressures to reduce use of these fuels; and the possibility of growing crops that can be used to meet on-farm energy needs. Click here

Evaluation of Soil Fumigants (Metam Sodium & Calcium Cyanamide) for Control of Violet Root Rot of Carrots (1998) F000947102

The objective of this project was to carry out two field trials to evaluate the efficacy of two soil-fumigants (metam and Calcium cyanamide) for the control of violet root rot in carrots. The results showed that soil fumigation with metam or Calcium cyanamide did not give effective control of root rot in carrots but metam gave a useful reduction in disease incidence in the harvested crop. Click here 

Fumigation of kumara with aerosol formulations of synthetic an neutral pyrethroids for control of tropical armyworm and opogona (2002) A0019403

The objective of the research described in this report was to assess the possibility of using existing aerosol formulations on natural and synthetic pyrethroids for the control of these important pests of stored kumara. The project found that Permigas was found to be useful for the control of TAW in kumara tubers in storage. Neither Pestigas nor Permigas at the dose rates evaluated can be recommended for the control of opogona infestations is kumara tubers. Click here

Greenhouse Nutrient Discharge Checklist - Part 1

This checklist is a self-audit to assist you in determining if your discharge of nutrient solution meets the permitted activity criteria of Auckland Council rules. If you do not meet the permitted activity criteria, you must apply for a resource consent from Auckland Council. If you need assistance in making this determination please contact one of the organisations listed in the PDF document. Click here.

Greenhouse Nutrient Discharge Decision Process - Part 2

Health attributes of roots and tubers (2006) F001412322 

This report focuses on the nutritional attributes of root vegetables and tubers: carrot, kumara, parsnip, taro, and yam. The depth of the information available varies considerably. Factors that may influence the nutritional profile of these vegetables, such as agronomical, cooking and processing and storage are covered. Some additional material of general interest has also been included. Click here

Health attributes of yellow/ orange vegetables (2005) F001435766

This report focuses on the nutritional attributes of yellow/ orange vegetables – carrot, corn, capsicum, pumpkin, and melon. Also discussed are the factors that may influence the nutritional profile of these vegetables and additional material of general interest. Click here

Health benefits of New Zealand vegetables (1998) F000991796

The aim of our current research is to collect data on the levels and composition of antioxidants in New Zealand-grown vegetables and compare our data with measures of the antioxidant activity of these vegetables. The vegetables examined in this study were: broccoli, carrots, cauliflower, garlic, kumara, lettuce, onions, potatoes, squash and tomatoes. Our research indicates that phenolics may be one of the most important classes of nutraceuticals in terms of their contribution to antioxidant activity. Click here 

Holding it Together (increasing nitrogen levels in vegetables) - Current

New Zealand’s vegetable industry relies heavily on the surface 15cm of soil. However, there are increasing concerns about the environmental and economic sustainability of current production practices which can expose this soil surface to damage from rainfall, irrigation and wind. This project, “Holding It Together”, aims to identify and implement improved best management practices for sustainable soil surfaces that address the challenges of key regions and land uses. Click here

Implementation phase for integrated pest and disease management (IPM) for outdoor head lettuce (2007) A0004426

The project work focused on crop scout training for different regions, replicated field trials, demonstration trials in commercial crops, continued monitoring of small insect pests, development of action thresholds for the major insect pests, dissemination of results through various publications and presentations, and producing a final version of the IPM manual/ guide. Click here   

Improved postharvest handling of fresh carrots for export (1997) F000991873

This project covers the second year of investigating postharvest handling practices for export carrots and aims to better define the storage potential of export carrots, including the new cultivar, Koyo II. The effects of harvest date and postharvest disease control on storage potential were measured as well as the influence of mechanical harvesting and washing on losses in storage. Click here

Improving the Competitive Advantage of New Zealand Garlic (1998) F001436365

The purpose of this work is to provide information about the levels of allicin in New Zealand Garlic which is the compound responsible for the distinctive taste and health benefits. It was found that New Zealand Garlic is higher in allicin that Chinese garlic, but lower than the Australian sample that was tested. Possible ways to increase allicin levels in New Zealand garlic are also discussed. Click here

Insecticides and host plants for New Zealand yam (Oxalis tuberosa) (2001) A0019407 

Two field trials were carried out to examine the effect of three insecticides (applied at different dates and times) on populations of grass grubs and white fringed weevils in yam crops. They found that the treatment with Confidor against grass grubs produced good results, especially when applied late and Oats were found to be good hosts for the white fringed weevil in the pot plant greenhouse trial. Click here

Integrated Pest and Disease Management (IPM) for outdoor lettuce - Final Report - Copy (2005) F001435801

A project was initiated to develop and implement an integrated pest management (IPM) programme for the control of insect pests and plant disease in outdoor lettuce to counter concerns about unsustainable crop protection practices and to control the new insect pest, lettuce aphid (LA), Nasonovia ribisnigri. The goal was to maximise non-pesticide controls while maintaining the efficacy of available and new pesticides. Click here

Integrated pest management (IPM) for lettuce – 12-month report to June 2003 (2003) F001006014

This project was initiated by the lettuce industry to develop and implement an integrated pest management (IPM) programme to control insect pests and plant diseases in lettuce to counter concerns about unsustainable crop protection practices and to control the new insect pest, lettuce aphid (LA) (Nasonovia ribisnigri). The goal is to maximise non-pesticide controls while maintaining the efficacy of available and new pesticides. Click here

Investigation into the Causes of Brown Centre in Sweet Potato (1999) F000975758 

The objective of this investigation was to identify the conditions that produce the disorder brown centre (BC) in sweetpotato. This project produced evidence based on tissue and soul analysis, as well as field experimentation, that the incidence of BC is exacerbated by fertile growing conditions. Based on the evidence it is suggested that in highly fertile fields the risk of BC might be lowered by initially growing crops other than sweetpotato or by growing a sweetpotato cultivar resistant to BC. Click here

MAF vegetable fertiliser trials – a reappraisal using a new model (1999) F000947029

The aim of this project is to work toward developing sustainable management practices by making accessible to fertiliser users our interpretation of past research on N, P and K fertiliser use on many New Zealand grown vegetables. The results from each of the five vegetable crops drew specific conclusions as to how the use of fertiliser response model compared to the conclusions possible from the original trials analyses. In most cases there will be substantial benefits to users in having the level of detailed information generated by the model. Click here

Methamidophos residues in Capsicum fruit (1999)

Crop & Food Research was commissioned by Vegfed’s Fresh Vegetable Sector to investigate methamidophos residues in capsicums resulting from applying the pesticide as a foliar spray. Their study suggests that the unacceptable levels detected in capsicum fruit by Progressive Enterprises Ltd may be the result of growers using non-conventional methods to apply the pesticide. With more growers turning to hydroponics to produce capsicum and other greenhouse vegetables, other methods of pesticide application may be used, such as adding pesticide to the hydroponic nutrient solution. Click here

New Ecologically-Based Control Strategies for Diamondback Moth in Vegetable Brassicas (1998) F001638393

The objective of this study was to develop a new selective and cost-effective control tactic for diamondback moth, compatible with organic production. The project largely focussed on the lure-and-infect project against diamondback moth, which is a pheromone-based strategy for spreading insect diseases that can be used as naturally occurring biological control agents. The project also investigated the lure and sterilize strategy, for possible combination with other tactics. Click here

Non – chemical control of kumara rots after washing (2007) A0019410

This report documents the results after carrying out a literature review seeking alternatives to the fungicide Botran for control of rots in kumara after washing and prior to consumption. It was conclude that hot water treatment is the most likely alternative to fungicide treatment and that improved sanitation may also offer an opportunity to reduce reliance to fungicide treatment. Click here

Novel biopesticides for systemic protection of root and tuber crops from nematodes and other pathogens : Interim report: January 2007 – June 2007 (2007) F001435674

This project aims to investigate the potential of bacterial proteins, in particular from the little-studied pathogens Pseudomonas corrugate, for the protection of root and tuber crops from a variety of plants pathogens. Click here

Novel biopesticides for systemic protection of root and tuber crops from nematodes and other pathogens – interim report, July-December 2007 (2007) F001436324

This project aims to investigate the potential of bacterial proteins, in particular from the little-studied pathogens Pseudomonas corrugate, for the protection of root and tuber crops from a variety of plants pathogens. Click here

Nutritional attributes of Brassica vegetables (2006) F001412336

This report focuses on the nutritional attributes of vegetables belonging to the Brassica genus: broccoli, cauliflower, cabbage, Brussels sprouts, broccoflower, Asian varieties of cabbage and broccoli, turnips and swedes. The depth of information varies considerably. Factors that may influence the nutritional profile of these vegetable, such as agronomy, cooking or processing, and storage, are covered. Some additional material of general interest has also been included. Click here

Nutritional attributes of herbs (2007) F001435677

The focus of this literature review will be primarily upon the compounds that give culinary herbs their health and flavouring properties, rather than on any common core nutrients they may also contain, since herbs are not consumed in sufficient quantities for these core nutrients to form a significant part of a diet. Click here

Nutritional attributes of legumes (2) Sprouted beans and seeds (2006) F001412386

This report is intended to be viewed as an adjunct to the report “The nutritional attributes of legumes” (which can be found below) and covers the germination process, microbial contamination and also sprouted legumes and sprouted brassicas. The report makes note of the fact that these products provide a good range of both nutrients and phytochemicals, but until more information is available, this conclusion is not definitive. Click here

Nutritional attributes of salad vegetables (2005) F001435797

This report focuses on the nutritional attributes of salad vegetables – lettuce, rocket, watercress, mesclun, cucumber, radish and celery. Also discussed are the factors that may influence the nutritional profile of these vegetables and additional material of general interest. Click here

Nutritional attributes of spinach, silver beet and eggplant (2007) F001435658

This report covers the health benefits of spinach, silver beet and eggplant. It was found that spinach and silver beet may have similar health benefits but greater research attention needs to be given to eggplant as there does not appear to be particular health attributes for eggplant or eggplant compounds. Click here

Onion thrips on lettuce – monitoring infestations and investigating prospects for control (2001) A0008093  

This study conducted by Crop & Food Research looks into the practicality of monitoring crops for thrips and thrips damage; compares the efficacy of the timing of insecticide spray applications in relation to the lifting of onions at topfall; and compares the impact of thrips infestation and control measures on small and large lettuce plants. This project confirmed that it is unwise to grow lettuce crops near onion crops in the summer – a few thrips can cause a lot of damage. Click here

Opogona and tropical armyworm control in kumara stores (2004) F001435749 

The objective of this research project was to test the efficacy of some new pesticides and fumigants for the control of opogona larvae and tropical armyworm in kumara stores. It was concluded that controlling opogona larvae is difficult and heat treatment may not be economically viable. It is recommended that storage facilities are maintained at 13-14°C to minimise insect activity during storage. Click here

Optimising fertiliser for profitable carrot production (2003) B0005241

In this project a Kayo carrot calculator was developed that forecasts crop yields and is a decision support tool for determining fertiliser requirements in order to grow better quality export grade Kayo table carrots. The key features of the Mountain Carrot Calculator include the possibility of a wide range of input variables; predicted yields are based on input variables; a yield graph is always on the desktop and automatically updated as input variables are changes; and a cost benefit analysis of fertiliser application is provided. Click here

Outdoor lettuce virus disease project 2016-2018 Year 1 Report summary

Over the past three seasons, lettuce (Lactuca sativa) growers in the lower North Island, Nelson and Mid Canterbury have been concerned about poorly performing outdoor lettuce crops. In particular, those growing iceberg /crisp head lettuce types have noticed seasonal crop collapses with losses as high as 50%. To read the first year full report please click here

 

Paraquat resistance in black nightshade (2005) F001435823

Paraquat resistance has been found in black nightshade, a weed in kumara crops in the Dargaville-Ruawai region. In this project it was found that diagnostic paraquat rates were determined to allow identification of standard, mixed and resistant black nightshade plant populations. Click here

Pesticide adjuvants for greenhouse growers (1998) F000947132

The aim of this study was to illustrate the importance of optimising adjuvant selection for pesticide spray applications to different crops. This report contains the final recommendations for greenhouse growers’ use of pesticide adjuvants and includes and reports on the effects of additives on crop wetting. The research found that the activity of contact pesticides was either reduced, or not affected by use of an adjuvant on two easy-to-wet greenhouse crops and the activity of systemic pesticides was either not affected, or enhanced by the use of adjuvants. Click here

Pesticide residues in hydroponic systems for growing capsicum (2003) A0019408

This study was carried out after it was discovered that there was a lack of information on pesticide residues in hydroponically grown vegetables. It looks to determine residue profiles of three pesticides: Apron, Confider and Vydate were applied in run-to-waste management systems under industry practice. They found that the growing medium may influence the accumulation of pesticides in capsicum, the type of growth medium used in growing capsicum may influence the amount of pesticide lost to the surrounding environment. Click here

Pesticide residue in hydroponic systems growing capsicum (2004) F001426585

A study was commissioned during the 2002/03 growing season to assess the amount of residues in capsicum fruit as a result of drenching three pesticides into two types of growing media. The results indicated that the type of growing medium and the nature of the pesticide used as a drench strongly influence the uptake and accumulation of the pesticide in the fruit. Click here

Postharvest handling of fresh carrots for Asia (1995) F000991519

This report covers the first year of investigation into the postharvest handling practices for export carrots. The main emphasis has been on trying to identify the likely causes of poor market out-turns of carton-packed carrots sent to Asian markets. The research focused on measuring the storage potential of carrots stored at 0-1°C, on assessing the benefits of rapid cooling and good sanitation practices and on identifying important postharvest diseases. The report also makes a number of recommendations for improving the quality of export carrots and on the direction of future research. Click here

Potential of biofumigation for control of diseases caused by soil-borne sclerotial plant pathogens – a review (2007) F001319052

This review summaries research work done and progress to date on soil biofumigation or soil amendment using Brassica crops for control of diseases caused by sclerotial plant pathogens. It also identifies areas requiring additional study to determine if biofumigation can be used successfully under New Zealand conditions. Click here

Recent advances in vegetable virus research (1998) F000991470

This report covers the findings made while attending the Vegetable Virus Working Group meeting. The vegetable crops covered include tomatoes, Cucurbita, peas, Alliums and brassicas. Topics covered include descriptions of new diseases, control strategies, detection and diagnosis, new approaches to continuing problems, and opportunities for collaboration. Click here 

Simulated sea-freight of capsicums to Japan (2001) A0016810

This interim report describes results of a land-based trail aimed at stimulating palletized sea-freight transport of capsicums to Japan. It was found that Shrivel symptoms were common at the end of storage suggesting excessive moisture loss and rot incidence on fruit and mold growth on stems suggested a hygiene problem but the type of carton during storage was not important. Click here

Soil Incorporation of Fungicides for Control of Violet Root Rot of Carrots (1999) F000947093

The objective of the present study was to evaluate seven fungicides in an attempt to develop soil incorporation treatments for the control of violet root rot of carrot. The results showed that soil incorporation of fungicides did not control violet root rot of carrot or increase carrot yields. The main control measures against this disease should involve cultural practices, good soil drainage, early harvesting of crops and preventing the spread of infested soil. Click here

Soil nutrition effects on kumara root yield and quality (2006) F001319417

The current study is directed at understanding the mechanism by which brown centre (BC) is induced, so that the disorder can be more accurately predicted and controlled. This study confirmed that soil nitrogen is involved in the disorder, but that BC occurs independently of boron or calcium levels. Soil nitrogen levels also have significant effects on root yield and various aspects of quality. Click here

Survey of downy mildew of lettuce (1999) F000947050

This report aims to investigate the cause of loss of control of downy mildew on lettuce. It aims to determine the current status of downy mildew of lettuce and current practises used to control the disease in indoor and outdoor crops. The survey results showed that downy mildew on lettuces is a more serious problem in the south than the north island, which could be a result of weather conditions. Click here

Survey of growers of Asian brassicas – results and analysis (2006) F001319075

The objective of this report is to summarise information about pests and diseases in Asian brassicas gathered during a survey. This information describes the pest management practices followed by New Zealand growers of Asian brassicas. It can be used to evaluate the potential impact of integrated pest management (IPM) on these crops, and provide insight into the types of research needed to meet the needs of the Asian brassica industry in the future. Click here

 

The Sweetcorn Toolkit - Second edition updated 

Sweet corn is grown in New Zealand to supply domestic and export markets with fresh and processed product. The Sweetcorn Toolkit has now been updated in a second edition and provides extensive information and photographs to assist in growing the crop. To review the new update pdf please click here for part 1 part 2

Sweet Potato fertilizer trails (1999) F000946870

A trial was conducted in the Dargaville region to investigate the fertilizer requirements needed for Sweet Potato. There is some evidence to show that rain affected the trials through surface water flow and waterlogged soil. However, the levels of nitrogen in both leaves and roots responded to additions of nitrogen fertilizer. Click here

Sweet Potato herbicide trial (1999) F000946886

This study evaluated the effectiveness of a range of herbicides for use on sweet potato in the Dargaville region. The three herbicide treatments applied all produced various degrees of leaf chlorosis or leaf burn in the sweet potato plant without causing plant death. None of the other herbicide treatments or the hand-weeded treatment showed evidence of any damage to the sweet potato plants. Click here

TBG project: Sustainable control of insect pests in Brassicas – for period ending 31 March 2000 (2000)

The project focuses on developing sustainable control measures for diamondback moth (DBM), the key insect pest of vegetable brassicas, and integrates this approach with the control of other pests. The report addresses the major efforts and highlights for each of the six objectives that were achieved. Click here   

The nutritional attributes of Allium species (2007) A0019409

This report focusses on the nutritional attributes of vegetables belonging to the Allium genus – onions, garlic, leeks, spring onion and shallots. Factors that may influence the nutritional profile of these vegetables are covered and some additional material of general interest has also been included. Click here

The nutritional attributes of legumes (2006) F001319167

This report focuses on the nutritional attributes of legumes – peas, and beans. Factors that may influence the nutritional profile of these vegetables, such as agronomy, cooking and processing, and storage, are covered. Some additional material of general interest has also been included. Click here

The Principles of an Integrated Framework for Sustainable Vegetable Production (1999) F000947061

Principles of an integrated framework which identifies the interactions between the various components of sustainable vegetable production are outlined. This report concentrates on the factors that growers can influence directly by their management decisions. This framework can be used to identify gaps in our knowledge and where further research is required; check for ‘fish hooks’ in proposals for changes in crop management and in research proposals; and develop best management practices for sustainable vegetable production. Click here

Transfer of postharvest technology for fresh vegetables to exemplar growers (2000) A0019405

Vegfed contracted Crop & Food Research postharvest scientists and technologies to implement an extensive programme to upgrade the technology base of growers to improve the quality of produce in the market. This report summarises the activities undertaken as part of the project, highlights some of its successes, and assesses the impact of the project on the quality of fresh vegetables which are supplied to consumers by members of Vegfed and the profitability of these growers involved. Click here

Vegetables NZ Inc. invests in scientists of tomorrow - Current

“Manipulating plant defences for improved clubroot control” – Loreto Hernandez Maldonado. 

Clubroot is an on-going disease problem for growers of vegetable brassicas caused by the soil borne pathogen, Plasmodiophora brassicae.  Disease free fields are becoming rare and few chemical control options exist. Loreto will explore an alternative approach to disease management by stimulation of the host plant defence systems. Click here

Development of an information sheet for growers on managing black rot in kumara.

Validation of a molecular diagnostic tools:

For rapidly assessing insecticide resistance status of aphid pests to enable growers to apply appropriate insecticides to avoid further resistance development.

Other projects include:

  • Compilation of nutrition & health benefits of vegetables for use in resource material by www.vegetables.co.nz
  • Investment in a joint project to produce a Land Management Index which measures changes in soil structures through land use changes
  • Hot water treatments for Kumara Storage Rots
  • Impacts of soil nutrition and the development of brown centre in kumara
  • The development of novel biopesticides
  • A project to test the ability of silicon as a fertiliser or foliar spray to reduce the severity of several diseases that are difficult to control by conventional methods. This is a joint project with Australian researchers
  • Identification and management of parsley root rot. This a project being undertaken by Australian researchers which Vegetables NZ is co funding
  • Survey for potential biological control agents of Diamond Back Moth

 

Click here for the capsicum and tomato  industry’s Code of Practice pdf document that will assist in the management of TPP and the associated disease causing organism Ca. L. solanacearum.