Hort. Series # 235

Principle Investigators

Jonathan R. Schultheis, Professor and Extension Specialist Keith D. Starke, Agricultural Research Associate

General Cultural Practices

The squash study was established on black plastic mulch. Pesticides used on all plots were chemicals labeled for that crop, 2019 North Carolina Agricultural Chemicals Manual.

Acknowledgments

We gratefully acknowledge the assistance of Cathy Herring, (Superintendent), and Charles Barrow, (Horticulture Supervisor, Central Crops Research Station, Clayton, NC), as well as, the personnel at the research station for their help in establishing, maintaining, and harvesting the squash cultivar evaluation study. We want to acknowledge the following summer employees for their assistance with the study: Maxton Collins, Ryan Jarret, Benjamin Indermaur, Lauren McAllister, Tanner Seay, and Emma Westbrook. We would also like to thank Joy Smith for conducting the statistical analysis on the data that were collected in this study. The cooperation and support from Clifton, Bejo, Enza Zaden, HM Clause, Rijk Zwaan, Seedway, Seminis/Monsanto, Syngenta and United Genetics are also appreciated. We also want to acknowledge, support for this study was provided by the US Department of Agriculture, National Institute of Food and Agriculture, for the CucCAP Specialty Crop Research Initiative grant under award number 2015-51181-24285.

Disclaimer

This publication presents data from the cultivar evaluation study conducted during 2019. Information in this report is believed to be reliable but should not be relied upon as a sole source of information. Limited accompanying detail is included but excludes some pertinent information, which may aid interpretation.

2019 Zucchini Squash Cultigens and Seed Companies

View images of each squash cultivar in the PDF booklet.

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Table 1.1 Zucchini Squash cultigen study yields¹, number of 20 lb boxes per acre, per indicated harvests for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred 24, 26 and 28 June; 1 and 3 July 2019. ² Culls consisted primarily of misshaped fruit.

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Table 1.2 Zucchini Squash cultigen study yields¹, number of 20 lb boxes per acre, per indicated harvests for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred 24, 26 and 28 June; 1 and 3 July 2019. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 2. Zucchini Squash cultigen study yields, cumulative boxes, (20 lbs.), per acre, among all harvests¹. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred 24, 26 and 28 June; 1 and 3 July 2019. ² Culls consisted primarily of misshaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 3. Zucchini Squash cultigen study yields¹. Percentage marketable, cull, and virus symptomatic fruit per indicated harvests by number of 20 lb boxes for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred on 24, 26 and 28 June; 1 and 3 July 2019. ² Culls consisted primarily of misshaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 4.1. Zucchini Squash cultigen study yields¹, average number of fruit per plant, per indicated harvests for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred on 24, 26 and 28 June; 1 and 3 July 2019. ² Average number of fruit harvested from each plant at each harvest period (i.e.: 1-5; 6-10; 11-15). ³ Culls consisted primarily of misshaped fruit.

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Table 4.2. Zucchini Squash cultigen study yields¹, average number of fruit per plant, per indicated harvests for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred on 24, 26 and 28 June; 1 and 3 July 2019. ⁴Fruit were discolored or rough/disfigured due to virus.

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Table 5 . Zucchini squash cultigen study. Cumulative fruit weight and percent per plant among all harvests¹. Clayton, NC, 2019.

¹ Total of 13 harvests. ² Culls consisted primarily of mishaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 6. Zucchini squash cultigen study yields, cumulative fruit number per plant and percent per grade among all harvests¹. Clayton, NC, 2019.

¹ Total of 13 harvests. ² Culls consisted of primarily misshaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 7. Zucchini squash cultigen study. Cumulative fruit number per acre and percentages, among all harvests¹. Clayton, NC, 2019.

¹ Total of 13 harvests. ² Culls consisted of primarily misshaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 8.1. Zucchini squash cultigen study yields¹. Number of fruit per acre by grade per indicated harvests for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred 24, 26, and 28 June; 1 and 3 July 2019. ² Culls consisted of primarily misshaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 8.2. Zucchini squash cultigen study yields¹. Number of fruit per acre by grade per indicated harvests for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests. Planting was 2 May 2019. Harvests 1-3 occurred on 5, 7 and 10 June; Harvests 4-8 occurred on 12, 14, 17, 19 and 21 June; Harvests 9-13 occurred 24, 26, and 28 June; 1 and 3 July 2019. ² Culls consisted of primarily misshaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 9. Zucchini squash cultigen study¹. Percent fruit number per acre per indicated harvests for replicated treatments. Clayton, NC, 2019.

¹ Total of 13 harvests . Planting was 2 May 2019. Harves ts 1-3 occurred on 5, 7 and 10 June; Harves ts 4-8 occurred on 12, 14, 17, 19 and 21 June; Harves ts 9-13 occurred 24, 26 and 28 June; 1 and 3 July 2019. ² Culls consisted of primarily misshaped fruit. ³ Fruit were discolored or rough/disfigured due to virus.

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Table 10. Zucchini Squash cultigen study - Percent plant stand count and average fruit length and width among replicated treatments. Clayton, NC, 2019.

¹ Final plant stand count was taken on 28 May 2019.

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Table 11. Zucchini Squash cultigen study - Plant growth quality data. Clayton, NC, 2019.

¹ Plant architecture ratings are on a scale of 1-10; 1 = open, 10 = dense. ² Color ratings are for fruit on a scale of 1-5; 1 = pale green , 5 = dark green. ³ Speckling ratings are for fruit on a scale of 1-5; 1 = no speckling , 5 = very high speckling ⁴ Spine ratings are for plant foliage on a scale of 1-10; 1 = no spines, 10 = coarse and many spines. ⁵ Vigor ratings are for plant foliage on a scale of 1-10; 1 = small plants, 10 = robust, vigorous plants.