{"data":{"posts":[{"id":2,"image":{"id":52,"parent_id":null,"name":"AdobeStock_9807542.jpeg","description":null,"folder":null,"storage":"assets","size":1628977,"extension":"jpeg","mime_type":"image\/jpeg","width":4139,"height":2754,"keywords":null,"usage":{"news_posts.2":"Carnarvon Melon Field Day"},"created_at":"2025-11-28T04:30:16.000000Z","updated_at":"2025-12-01T22:21:50.000000Z","value":null,"_meta":null,"node_path":[{"id":null,"name":"AdobeStock_9807542.jpeg","parent_id":null}],"readonly":null,"link":"\/asset\/52.jpeg","readable_size":"1.55 MB","secured":false,"secured_token":"eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdG9yYWdlcyI6WyJzZWN1cmVfYXNzZXRzIl0sImZpbGUiOjUyfQ.Zfw4eWM1jfojFDxx78rFOsTpXvZlSGlzV200vuUSTkw","full_path":""},"news_category_id":null,"name":"Carnarvon Melon Field Day","title":"Carnarvon Melon Field Day","content":"<p><img style=\"display: block; margin-left: auto; margin-right: auto;\" src=\"\/asset\/51.jpeg?asset_token=eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdG9yYWdlcyI6WyJzZWN1cmVfYXNzZXRzIl0sImZpbGUiOjUxfQ.445OQKn_hIi7WarM3kc0sseAXboBoqRfo4nCaxg5zhs\" width=\"600\" height=\"593\" \/><\/p>","name_id":"carnarvon-melon-field-day","meta_description":null,"meta_keywords":null,"template":"default","position":2,"active":1,"available_at":"2025-11-28T04:26:04.000000Z","created_at":"2025-11-28T04:26:55.000000Z","updated_at":"2025-12-01T22:21:50.000000Z","import_id":null,"intro":null,"layout_id":null,"header_image":null,"author_id":null,"categories":[]},{"id":3,"image":{"id":65,"parent_id":50,"name":"THUMB.jpg","description":null,"folder":null,"storage":"assets","size":238368,"extension":"jpeg","mime_type":"image\/jpeg","width":688,"height":460,"keywords":null,"usage":{"news_posts.3":"GREENING PROBLEMS IN YELLOW SQUASH AND ZUCCHINI"},"created_at":"2025-12-02T01:27:02.000000Z","updated_at":"2025-12-02T01:29:00.000000Z","value":null,"_meta":null,"node_path":[{"id":50,"name":"EVENTS AND ARTICLES","parent_id":null},{"id":null,"name":"THUMB.jpg","parent_id":"50"}],"readonly":null,"link":"\/asset\/65.jpeg","readable_size":"232.78 kB","secured":false,"secured_token":"eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdG9yYWdlcyI6WyJzZWN1cmVfYXNzZXRzIl0sImZpbGUiOjY1fQ.DDbHaLhHmHCxJQvXk4r1pKSzMYJ8A0fVPdwe6-wsSog","full_path":"50\/"},"news_category_id":null,"name":"GREENING PROBLEMS IN YELLOW SQUASH AND ZUCCHINI","title":"GREENING PROBLEMS","content":"<p>Most squash growers have at some stage experienced problems with greening or spotting in yellow squash or zucchini varieties.<\/p>\n<p>There are two main reasons: plant stress and virus.<\/p>\n<h2><img src=\"\/asset\/63.jpeg\" alt=\"Greening-problems-in-yellow-squash-and-zucchini.jpg\" \/><\/h2>\n<h2>Breeding Background and Plant Stress Effects:<\/h2>\n<p>A hybrid is a cross of two parent lines, these parents can be relatively similar or distinctly different, depending on the hybrid characteristics the plant breeder requires. The parental lines for yellow squash are very different, one parent is yellow, the other is a solid green colour. The gene responsible for the yellow colour is the dominant gene, which is why yellow squash are mostly yellow in colour. The issue comes under periods of high stress (usually hot weather, can also be nutritional stress, drought or disease pressure) when the dominant yellow gene can break down, resulting in green or mottled green and yellow fruit. If these stresses can be removed, the plant will begin to produce yellow fruit once again.<\/p>\n<h2>Virus Effect:<\/h2>\n<p>ZYMV (Zucchini Yellow Mosaic Virus) is also one of the major causes of greening in squash and other cucurbits, particularly in the Southern growing regions in Australia, or in Western Australia. PRSV (Papaya Ringspot Virus) is the predominant virus in Queensland growing regions.<\/p>\n<p>The main difference between greening from virus and greening from heat, is that the virus will affect yield as well as fruit appearance. Fruit will tend to have a glassy clear appearance and show a more regular green and yellow circular pattern giving a spotted effect. Virus affected fruit may also tend to have a lumpy uneven appearance. Virus affected plants will have leaves that are mottled in appearance and in extreme cases can have leaves with a bubbled look to them. Virus may strike early, affecting even first crop harvests, leaving growers to mistakenly think they have received the wrong variety.<\/p>\n<p>Experience has shown that the same seed lots sown in a range of areas can show dramatically different effects. In virus prone areas, a seed lot may experience significant greening problems. The same seed lot sown in an isolated area without virus pressure and mild conditions, however, will produce normal high quality yellow squash.<\/p>\n<p>Heavy aphid infestations can be devastating, good crop practices can help to reduce potential problems. Some of the latest research indicates that virus is spread more so now by mechanical means rather than insect transmission. If you harvest with a knife, please ask the harvest crew to clean and disinfect the picking knives regularly, and to try not to harvest fruit off infected plants. Many growers will now refrain from asking the harvest crew to remove infected plants from the field for fear of spreading the virus through sap transmission. The best advice, however is to avoid growing at the time when virus can be problematic.<\/p>\n<p class=\"small\"><em>The information provided is based on an average of data and observations collected from our trials. Significant variations may occur in the performance due to a range of conditions including cultural\/management practices, climate, soil type and geographic location. As a consequence South Pacific Seeds cannot accept any liability as to the accuracy of this information. MAY 2022. ACN 002 887 256<\/em><\/p>","name_id":"greening-problems","meta_description":null,"meta_keywords":null,"template":"default","position":3,"active":1,"available_at":"2025-12-02T01:10:37.000000Z","created_at":"2025-12-02T01:10:36.000000Z","updated_at":"2025-12-02T01:29:00.000000Z","import_id":null,"intro":"Most squash growers have at some stage experienced problems with greening or spotting\nin yellow squash or zucchini varieties. There are two main reasons: plant stress and virus.","layout_id":null,"header_image":null,"author_id":null,"categories":[]},{"id":4,"image":{"id":70,"parent_id":50,"name":"Managing-potyvirus-THUMB.jpg","description":null,"folder":null,"storage":"assets","size":359610,"extension":"jpeg","mime_type":"image\/jpeg","width":688,"height":460,"keywords":null,"usage":{"news_posts.4":"Managing potyvirus disease on zucchini in Australia"},"created_at":"2025-12-02T01:42:41.000000Z","updated_at":"2025-12-02T01:42:49.000000Z","value":null,"_meta":null,"node_path":[{"id":50,"name":"EVENTS AND ARTICLES","parent_id":null},{"id":null,"name":"Managing-potyvirus-THUMB.jpg","parent_id":"50"}],"readonly":null,"link":"\/asset\/70.jpeg","readable_size":"351.18 kB","secured":false,"secured_token":"eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdG9yYWdlcyI6WyJzZWN1cmVfYXNzZXRzIl0sImZpbGUiOjcwfQ.LZv_SW7G8bEtCLu1T-jj7sq2lckhBsOzKHM1tdQ3kyo","full_path":"50\/"},"news_category_id":null,"name":"Managing potyvirus disease on zucchini in Australia","title":"Managing potyvirus disease on zucchini in Australia","content":"<h2>Introduction<\/h2>\n<p>Virus disease is a major limiting factor to zucchini production in Australia. The major cause of loss is by three viruses spread by aphids and belonging to a virus group called potyviruses.<\/p>\n<p>Papaya ringspot virus-type W (PRSV-W) is the main virus found in Queensland while Zucchini yellow mosaic virus (ZYMV) dominates in Western Australia. Watermelon mosaic virus (WMV) occurs in all regions and has been particularly prevalent in the Swan Hill area in Victoria.<\/p>\n<p>Rapid aphid transmission and the abundance of host crops frequently results in very high disease levels by early flowering. Affected crops have reduced fruit set and high numbers of deformed unmarketable fruit. Due to aphids being able to spread these viruses in feeding times of less than one minute insecticides are seldom effective in reducing virus spread and crop hygiene to reduce inoculum levels is often poorly implemented.<\/p>\n<p>Over the last decade or so considerable investment has been made by seed companies in developing C. pepo varieties with tolerance to the potyviruses and in some instances to Cucumber mosaic virus. Several genes such as Prv and zym have been used in various combinations. The varieties are tolerant not highly resistant in that plants do become infected following either aphid inoculation or sap inoculation in greenhouse tests. The value of the varieties is their capacity to produce good yields of saleable fruit under considerable virus pressure.<\/p>\n<p>Previous work some five years ago had demonstrated the value of tolerant zucchini varieties in reducing the impact of virus disease in the crop. In project VG 16086, the work has been expanded and new generation varieties compared with those previously available. Three trials have been completed in 2019, at Gatton (January, DAF QLD), Bundaberg (April-June, Agreco Australia) and Bowen (August-September, Prospect Agriculture). The aim was to assess varieties for tolerance\/ performance in the presence of PRSV.<\/p>\n<p><img src=\"\/asset\/69.jpeg\" alt=\"Managing-potyvirus-IMAGE1.jpg\" \/><\/p>\n<h2>Methods - summary<\/h2>\n<p>Trial design was four replicates with single row plots with 10 plants\/ plot at 0.5m spacing. Squash plants inoculated with PRSV were used as virus reservoirs to allow aphid transfer to test plots. Test plants were not directly inoculated with virus. There were 16 varieties in the Gatton trial; 12 at Bundaberg and 27 at Bowen.<\/p>\n<p>Data were collected on virus incidence, symptom severity on plants and fruit and aphid populations. Virus severity was rated using a 0-7 scale with 1=very mild symptoms and 5 to 7 severe to very severe symptoms. Yield data were collected on at least three occasions in each trial. Total yields, yields of marketable fruit and severity of virus symptoms on fruit were measured. Selected symptomatic plants were sampled for molecular testing for PRSV, ZYMV and WMV to determine their virus status.<\/p>\n<h2>Results - summary<\/h2>\n<p>Varieties ranked as highly tolerant over three trials were Desert, Apollonia, Alessandra, Ebano, 003-6, Baily<\/p>\n<p>These varieties developed only very mild leaf symptoms and had few if any fruit symptoms. This tolerance was reflected in high yields of marketable fruit with little wastage.<\/p>\n<p>Varieties with intermediate tolerance were: Seduction, Rosa, Eva, Pascola<\/p>\n<p>These varieties developed leaf symptoms of intermediate severity (2-3 on severity scale). Moderate virus symptoms were seen on a proportion of fruit.<\/p>\n<p>Susceptible varieties included Regal Black and Amanda. Varieties in this group had leaf and fruit symptoms 5 to 7 on the severity scale.<\/p>\n<p>The only virus detected in symptomatic plants tested by molecular assays was PRSV.<\/p>\n<p><img src=\"\/asset\/68.jpeg\" alt=\"Managing-potyvirus-IMAGE2.jpg\" \/><\/p>\n<h2>Conclusions<\/h2>\n<p>At least six zucchini varieties have been identified as having excellent tolerance to PRSV in Queensland. All are worth evaluation by growers on their own properties to decide which varieties are best suited to the local environment and market requirements. It is likely that the varieties highly tolerant to PRSV will also perform well against ZYMV but this needs to be demonstrated in trials in WA and elsewhere. Arrangements to do this have been made.<\/p>\n<h2>Key points for virus management<\/h2>\n<p>While virus tolerant varieties are a valuable tool for virus management they should be used as part of an integrated approach to delay virus infection and reduce the overall virus levels in crops. Actions which help reduce movement of the aphid vectors into crops or between crops is a very positive step towards managing disease caused by potyviruses.<\/p>\n<p>Measures which can be used include:<\/p>\n<ul>\n<li>destroy harvested or abandoned cucurbit crops as soon as practically possible. These crops are very important sources of potyvirus and aphids on farm and within the district. Undertaking this across neighbouring farms or across a production area will have greater positive impact.<\/li>\n<li>separate new crops from maturing crops where possible. Separating crops by as little as 50 to 100 m can be beneficial and planting new crops upwind from older crops can also help<\/li>\n<li>separate cucurbit crops using blocks of unrelated non-host species<\/li>\n<li>consider tall barrier crops to separate blocks<\/li>\n<li>use and select insecticides with caution. None are registered for control of virus diseases as mostly they have no useful effect on the spread of potyviruses by the aphids. Instead, they can have a negative effect if they disrupt natural enemies and make the plants less pleasant for the aphids to feed on which increases their movement through the crop. If the aphids move around a lot tasting plants instead of settling and feeding, they will spread the virus as they go resulting in more disease.<\/li>\n<li>applying refined mineral oils and planting into reflective plastic mulch can reduce or delay virus infection but results are variable. Their effectiveness depends on factors like frequency of application to ensure new leaves are protected and rate of crop growth over mulched rows.<\/li>\n<\/ul>\n<h2>Further information<\/h2>\n<p>For further information please contact Denis Persley (Denis.persley@daf.qld.gov.au) or Mobile 0402 331 384<\/p>\n<p>Or the Project Leader: Cherie Gambley (cherie.gambley@daf.qld.gov.au) or Mobile 0423 200 211<\/p>\n<p class=\"small\"><em>This project has been funded by Hort Innovation using vegetable industry levies and contributions from the Queensland Department of Agriculture and Fisheries; Victorian Department of Economic Development, Jobs, Transport and Resources; The Northern Territory Department of Primary Industry and Resources; the Western Australia Department of Primary Industries and Regional Development and the University of Tasmania. It is supported by a second smaller project led by the New South Wales Department of Primary Industries and similarly funded by Hort Innovation using vegetable industry levies and contributions from the New South Wales Department of Primary Industries.<\/em><\/p>\n<p class=\"small\"><em><img src=\"\/asset\/67.jpeg\" alt=\"Managing-potyvirus-LOGOS2.jpg\" \/><\/em><\/p>\n<p class=\"small\"><em><img src=\"\/asset\/66.jpeg\" alt=\"Managing-potyvirus-LOGOS1.jpg\" \/><\/em><\/p>","name_id":"managing-potyvirus-disease-on-zucchini-in-australia","meta_description":null,"meta_keywords":null,"template":"default","position":4,"active":1,"available_at":"2025-12-02T01:28:13.000000Z","created_at":"2025-12-02T01:28:41.000000Z","updated_at":"2025-12-02T01:42:49.000000Z","import_id":null,"intro":null,"layout_id":null,"header_image":null,"author_id":null,"categories":[]}]}}