Quality and Storability of Trellised Greenhouse-Grown, Winter-Harvested, New Sweet Acorn Squash Hybrids

Abstract

Acorn squash (Cucurbita pepo) is a familiar fruit vegetable in North America, appreciated for its attractive appearance, good flavor, nutritional content and long storage life. A breeding program in Israel has produced three new acorn squash hybrids of enhanced sweetness and flavor. Presently, we evaluated productivity, quality, and storability of these new cultivars in fall plantings. The plants were grown trellised, in an insect-proof greenhouse, for fruit production during the winter to meet consumer demand. The plants were highly productive and bore fruits of superb quality, but there was a high incidence of fungal rots during postharvest cold storage. Pre-treating the fruits with hot water brushing and rinsing before storage was found effective in reducing rot incidence of the fruits stored at 15 °C, but only for one cultivar. Storing the fruits at 10 °C with reduced humidity (Rh 70%) enabled a 3-month shelf life with significantly reduced fruit-rot incidence and minimal effect on fruit quality of all three cultivars. Storage at 20 °C with reduced humidity was suitable for a 1-month period. These protocols for prolonging storage life will help attain controlled, gradual year-round marketing of quality acorn squash at uniform, reasonable price levels for farmers and consumers, and could facilitate overseas export.

Trellising is advantageous over ground culture for out-of-season, protected production and storage of sweet acorn squash

“…Values a* and b* represent the colors green to red and blue to yellow, respectively. Negative values a* and b* were reflective of a more greenish coloration of the fruit flesh while positive values were more toward yellow and orange coloration (Adeeko et al, 2020). These color-space values have been shown to be strongly correlated with carotenoid content in pumpkins and squash (Itle and Kabelka, 2009).…”

“…Fruit exocarp (rind) color before storage and at the end of storage was evaluated quantitatively using a Chromo Meter CR-400/410 (Konica Minolta, Osaka, Japan). Two measurements, using the color space L*C*h were taken near the blossom (stylar) end of each fruit and averaged (Adeeko et al, 2020). The color of the fruit rind is reported as hue angle (Hue°), corresponding to green and blue, which are positioned at 180°and 270°, respectively.…”

“…The strong consumer demand coupled with lack of supply of sweet acorn squash led us to attempt to utilize the available screenhouses in the Besor area for winter production. We have determined that such production is indeed quite feasible (Adeeko et al, 2020) but until now have not focused on determining whether growing the plants vertically, on trellises, would be advantageous to simply allowing them to grow sprawling on the ground. Our objective was to determine if trellising would be worthwhile for management of sweet acorn squash production in this environment, with regard to yield and quality of freshly harvested and stored fruits.…”

Hot Water Rinsing and Brushing of Fresh Produce as an Alternative to Chemical Treatment after Harvest—The Story behind the Technology

“…Treating these fruits with HWRB at 54 • C for 15 s and then storing them at 15 • C significantly maintained the fruit quality for 3.5 months, as indicated by the greater firmness of the fruits, a lower incidence of decay, and improved retention of the green skin color [11]. However, the effectiveness of this treatment varied depending upon the squash cultivar [12].…”

Comparison of Photosynthetic Characteristics and Reproductive Traits of Winter Squash (<i>Cucurbita maxima </i>L.) Between Cultivars

“…Winter squash fruit with a TSS content of 10-15°Brix, a starch content of 60-90 g/kg DW, and a sugar content of 400-500 g/kg DW are of standard quality. If squash meet the criteria mentioned above, the fruit after cooking will be loose, but not soft, and will have a sweetness and texture like that of a sweet potato [1,4]. These are the acceptable conditions for the fresh market.…”