2017 North Carolina Orange Flesh Melon Cultivar Evaluations
Horticulture Series # 220
Principle Investigators: Jonathan R. Schultheis, Professor and Vegetable Extension Specialist, Department of Horticultural Science, NC State University, Raleigh, NC 27695-7609 and Keith D. Starke, Research Associate, Department of Horticultural Science, NC State University, Raleigh, NC 27695-7609. Disclaimer This publication presents data from the cultivar evaluation trials conducted during 2017. 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.
General Cultural Practices
All melon trials were grown using recommended practices for commercial melon production in North Carolina. All plots in the study used black plastic mulch and were fertigated with drip irrigation. Furthermore, pesticides used on all plots were chemicals labeled for use on that crop, (2017 North Carolina Agricultural Chemicals Manual.
We gratefully acknowledge the assistance of Kathy Herring (Superintendent) and Brandon Poole (Horticulture Crops Supervisor), Central Crops Research Station, Clayton, NC, as well as, the personnel at the research station for their help to establish, maintain, and harvest the cultivar evaluation trials. We want to also acknowledge the following summer research assistants for their help with the trials: Steven Bajorek, Elizabeth Indemaur, Shannon Dexter, Katherine Phillips, and graduate students, Fernando Montero and Marlee Trandel. The cooperation and support of the following seed companies is also greatly appreciated: DP Seeds, LLC; HM Clause; Hollar Seeds; Nunhems USA, Inc.; Origene Seeds; Rijk Zwaan USA Inc.; Sakata Seed USA; Syngenta Seeds, Inc.; and VoloAgri.
The acreage for orange flesh melon production in North Carolina has not been published in recent years, however, it is estimated that 3,000 – 4,000 acres are under production in the state. Furthermore, the most recent report of US orange flesh melon production was in 2013 when US growers reported an increase of 8,300 acres for orange flesh melon production bringing the total orange flesh melon acreage to 74,730. Although, the total value of the 2013 orange flesh melon crop was reported at $319 million, total crop value actually decreased by $6 million from the previous year when the crop was valued at $325 million. Further reporting showed domestic orange flesh melon prices have steadily declined from their peak of .25/lb in 1980 to a season-average of .18/lb in 2013. The majority of melons grown in North Carolina are eastern type with ‘Athena’ being the principle cultivar produced for more than two decades. In addition to the eastern type orange flesh melon, other orange flesh melons being grown on much smaller acreage include Extended Shelf Life (ESL), Long Shelf Life (LSL) melons, often termed Harper melons; and a third type termed Italian (Tuscan) melons. The Extended or Long Shelf Life melons, as the name suggests, will hold for a longer period than the eastern type melons. Flesh firmness and sweetness tend to be higher in the ESL or LSL type melons. Greater flesh firmness allows the fruit to hold up better over time. This trait increases the ship ability, a term often referred to as giving the fruit ‘better legs’. It can be more difficult to determine readiness on LSL melons and this has delayed willingness from growers to move into larger scale production of these melons. More recently, the release of new cultivars with ESL traits have performed well for growers and have received favorable support from consumers. Two such examples would be ‘Accolade’ and ‘Astound’ that were released by Syngenta in 2016. It is reported that these new varieties have taken as much as 30% of the market from ‘Athena’, an Eastern type melon that has dominated the market in the Southeastern production region for more than twenty years. The Italian (Tuscan) type melons tend to split easier than the ESL/LSL or Eastern types and more intense management of the crop harvest may be necessary in order to minimize fruit loss due to splitting. In spite of these weaknesses with ESL/LSL and Italian (Tuscan) type melons, North Carolina growers have had some success in producing and marketing these newer melon types. In 2017 several new cultigens were evaluated in our melon field trial and we had a total of 24 advanced lines or cultivar entries (cultigens) from 9 seed companies. Although Pixie and Tasty Bites are specialty mini-melons they were included in this trial due to their interior orange flesh characteristics. All entries were evaluated for yield, earliness, and various other qualities.
Materials and Methods
In February and March commercial seed companies were contacted to obtain seed for the orange flesh melon cultigen evaluation trial. Seed were sown into 72 cell Poly trays to grow transplants (Hummert Int.; Earth City, MO) on 13 April 2017. The planting medium used was a Fine Germinating Mix, a commercial soilless mix (SunGro, Agawam, MA). In November 2017 the field trial area (0.28 acre) was fumigated with Telone 17 and a cover crop was established. On 23 March the field trial area was plowed using a disc harrow and then cultivated on 27 March. A complete fertilizer (12-6-24 @ 400 lbs/ac) was broadcast applied and black polyethylene plastic mulch (0.70 mil thick high density plastic film, 48 inches wide; B.B. Hobbs, Clinton, NC) was laid in the field on 28 March. Herbicide products, Prefar (6 qt/ac), Curbit (4.5 pt/ac) and Honcho Plus (1.5 pt/ac) were applied to row middles for pre-emergent weed control on 21 April. Orange flesh melon transplants were approximately 3 weeks old when placed in a “hardening” greenhouse for 7 days prior to being established in the field on 2 May. A starter fertilizer was applied at transplant (0.5 lb of 20-20-20, water soluble fertilizer/50 gal H2O). Plot size was one row with 10 plants per plot (20 ft) with in-row spacing of 2 feet and between-row spacing of 5 feet. Field arrangement for the orange flesh melon cultigen trial was a Randomized Complete Block Design (RCBD) with four replications. Plots with missing plants were replanted approximately 7 days after transplanting to achieve 100% stand, in most cases. Drip irrigation was utilized (NETAFIM, 12 inch spacing, 0.24 gal/hr; NETAFIM, Tel Aviv, Israel) throughout the growing season. Fertigation, using 7-0-7 liquid fertilizer, was initiated 15 days after planting applied weekly, thereafter. The first application of liquid fertilizer (2.5 gal) was applied through the drip tube on 17 May and the last application (3.5 gal) was applied 9 August. Fertilizer was applied either preplant or through fertigation in this trial. Total amount of fertilizer applied through fertigation for the season was 41 lbs/ac of N and 41 lbs/ac of K2O. The total amount of fertilizer applied for the entire growing season was 89 lbs/ac of N, 24 lbs/ac of P2O5 and 137 lbs/ac of K2O. Insecticides were applied as needed throughout the growing season beginning 31 May and followed by subsequent applications on 7, 21 and 28 June; 5 and 12 July 2017. The following insecticide products were alternated throughout the season to avoid potential resistance development in insect species; FanFare and PermUp. Similarly, the following fungicide products were applied; Bravo, Endosulfan, Pencozeb, Previcure Flex, Quadris, Quintec and Ranman; and applied on the following dates; 9, 26 and 31 May; 7, 21 and 28 June; 5, 12 and 25 July 2017. There were a total of 13 harvests for the orange flesh melon evaluation trial. The first harvest was 30 June 2017 and the thirteenth harvest was 7 August 2017. Harvests were made three times per week on Monday, Wednesday, and Friday. Each fruit was harvested when ripe and weighed. Evaluations of each melon entry included; yield, fruit size, production earliness, soluble solids (using a digital refractometer), fruit shape and size, exterior and interior descriptions (rind, length/ width ratio, and flesh color), and interior flesh firmness. Flesh firmness was measured (recorded in pounds) by using a Penetrometer FT 011 with a 5/16” plunger tip, (QA Supplies LLC, Norfolk, VA). Melon samples were obtained by cutting the center of the fruit, lengthwise, from the fruit’s stem end to blossom end. Pressure measurements were then taken between the interior fruit cavity and the rind (near fruit bottom or ground spot and one from the top of the fruit) on each half of the cut fruit. The reported measures on flesh firmness are an average of the two sample areas from five fruit per plot (for flesh firmness 10 total fruit halves were measured per plot). Most of the quality measurements were taken when the melons became ripe between the first and fourth harvests for a given cultigen. The field and growing conditions throughout the harvest period were normal for this trial. There was average to above average rainfall throughout the month of June and July, as well as, optimal ambient temperatures that allowed for good plant growth and fruit set within all the cultigen plots.
In the early harvests (1-4) entries that yielded over 100 cwt were Accolade, Astound, Athena, Cayucos Beach, HMX4606, ME4858 and Tasty Sherbert. The highest yielding entries based on fruit numbers that exceeded 3,000 fruit per acre for early harvests (1-4) were Astound, Athena, Cayucos Beach, HMX4606 and Tasty Sherbert. The 3 to 7 lb. size category had the highest percentage of fruit produced from the early yielding entries. This is the most desirable and marketable size category for orange flesh melons, however, the entries Pixie and Tasty Bites are orange flesh specialty melons that will consistently produce smaller or more “personal” sized fruit. Despite their smaller size, these two cultivars have orange flesh and were therefore evaluated in the orange flesh culigen trial evaluation conducted in 2017. The highest yielding entries for fruit weight in the mid-season harvests (5-8) were 300 cwt were 8H288, 8H405, 8H423, Durawest and NUN4346 (Table 5). 5 The entries that yielded the highest (>5,000 fruit number) in the mid-season (harvests 5-8) were 8H288, 8H403, 8H405, 8H423, 8H424, Durawest, Infinite Gold, MS4344, NUN7609, NUN26191, Pixie, Tasty Bites and USAMR 50785. Most fruit produced from these entries were between 3 to 7 lbs.; with the exception of Pixie and Tasty Bites which, had 61 and 58% of their fruit in the < 3 lb. size category, respectively. Fruit in the < 3 lb. category would ordinarily be culled, however, Pixie and Tasty Bites are smaller melons that are being marketed as ‘personal’ size and ‘single’ serving melons. Some of the latest yield in (harvests 9-13) melon entries > 150 cwt were 8H300, 8H312, Cayucos Beach, HMX4606, Infinite Gold, NUN26191, Tasty Bites, USAMR 50785and USAMR 50786. Average fruit size for these entries were 5.1, 5.7, 4.9, 3.8, 5.3, 4.0, 3.4, 4.6 and 4.0. The highest yielding entries across all harvests, in terms of tonnage (> 450 cwt) were 8H288, 8H300,8H312, 8H405, 8H423, Accolade, Astound, Cayucos Beach, Infinite Gold, NUN4346, Tasty Sherbert and USAMR 50785. The melon entries that produced the greatest number of fruit (> 9,000) across all harvests were 8H300, 8H403, 8H405, 8H423, 8H424, Accolade, Astound, Athena, Cayucos Beach, HMX4606, NUN26191, Pixie, Tasty Bites, Tasty Sherbert and USAMR 50785.
In addition to the seed companies, this program has been supported by the College of Agriculture & Life Sciences, the North Carolina Agriculture Research Service, and the North Carolina Cooperative Extension Service.