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  • Author or Editor: G. S. Nelson x
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Abstract

Seed lots of several vegetables, including garden beans, cabbage, cantaloupe, cucumber, lettuce, okra, onion, garden peas, pepper, spinach, and tomato, and two seed lots of Kentucky bluegrass were exposed to 40-MHz radiofrequency (RF) electric fields and tested to determine the influence of the electrical treatment on germination performance. Germination was significantly increased by RF treatment through reduction of hard-seed content in beans, okra, and peas. Acceleration of germination was evident in seed lots of bluegrass, tomato, and spinach. It was particularly marked and consistent with spinach. Acceleration of spinach emergence was also noted in soil tests. The influences of seed moisture content, seed size, and characteristics of the RF electric field were also considered. Improved responses are attributed to thermal stresses developed in seed during RF treatment, but further research is recommended to explain the responsible mechanisms.

Open Access

Abstract

Early introduction of honey bees into caged ‘Jersey’ blueberries was associated with increased yields and fruit size and suggests that hives be introduced in plantations for pollination not later than 25% of full bloom.

Open Access

Annual-hill strawberry (Fragaria ×ananassa Duch.) production with black plastic mulch and drip irrigation is gaining popularity in North Carolina. Two experiments (E1 and E2) were conducted on a Wagram loamy sand (Arenic Kandiudult) in 1992 and on a Norfolk sandy loam (Typic Kandiudult) in 1993 to investigate the effects of fall-applied N and spring-applied N and K on `Chandler' strawberry yield and fruit quality. E1 treatments included factorial combinations of banded fall-applied N (0, 34, and 67 kg·ha-1) and drip spring-applied N (0, 0.19, 0.37, 0.56, and 0.75 kg·ha-1·d-1 and 0, 0.37, 0.75, and 1.12 kg·ha-1·d-1 in 1992 and 1993, respectively). E2 treatments included combinations of drip spring-applied N (0.56, 1.12, 1.68, and 2.24 kg·ha-1·d-1) and K (0.46, 1.39, and 2.32 kg·ha-1·d-1 and 0, 0.75, 1.49, and 2.24 kg·ha-1·d-1 in 1992 and 1993, respectively). There were no significant interactions among main effects for any of the measured variables. Market yield maximized with total N at ≈120 kg·ha-1 with one-half banded in the fall and the remainder drip-applied in the spring. Fruit firmness decreased with increasing N rate. Fruit pH and concentrations of total acids and soluble solids were not affected by N treatments, but soluble solids increased as the harvest season progressed. Plant crown number was not affected by N treatment but crown yield increased with N rate similar to market yield. There was no response to drip-applied K for any variable in either year. Based on soil test, fall-applied K (broadcast-soil incorporated) met the K requirements both years.

Free access

Abstract

Succinic acid-2,2-dimethylhydrazide (daminozide) applied to ‘Raven’ blackberries at 4000 ppm and to ‘Raven’ and ‘Brazos’ at 2000 ppm between full bloom and first color development and at 2000 ppm in a multiple application applied at full bloom, 2 weeks, and 3 weeks after full bloom resulted in reduced berry size and yield with no beneficial effects on fruit quality. (2-Chloroethyl) phosphonic acid (ethephon) applied to the same cultivare at 1000 ppm 4 days prior to the first harvest increased the amount of fruit mechanically harvested on the first harvest. Ethephon treatment improved color but resulted in mechanically harvested fruit having lower soluble solids and acidity.

Open Access

Abstract

Gibberellic acid (GA) applied at 20 ppm 4−6 weeks before harvest increased the ascorbic acid content of fresh and processed ‘Rainier’ cherries (Prunus avium L.) while also increasing fruit size and yellow color. Anthocyanin content was also reduced. GA treated fruit rated higher according to USDA processed fruit grades. Ascorbic acid content did not change with maturity. There was no interaction between GA and maturity on ascorbic acid content (2-Chloroethyl)phosphonic acid (ethephon), applied at 500 ppm 1 to 3 weeks before harvest, reduced fruit size compared with untreated fruit. Fruit treated with succinic acid-2,2-dimethylhydrazide (daminozide) at 2000 ppm 2 weeks after full bloom reduced the weight per fruit after processing but not before processing. This was reflected in a greater loss in drained weight. Daminozide increased anthocyanin content and reduced yellow and green color of fresh fruit.

Open Access

Abstract

The development of a mechanical harvester for erect blackberries is traced from its inception to commercialization. The harvesting and production system tested in this study required productive, erect cultivars that are mechanically pruned to form continuous hedgerows. An acceptable processed product is obtained from the system.

Open Access

Abstract

A completely mechanized system for production, harvesting and handling strawberries (Fragaria × anassa Duch.) for processing is described. Pre-harvest cultural factors, including bed preparation, plant population, harvest date and clonal evaluation and adaptability to mechanical harvesting, were studied for 4 years. ‘Cardinal’, ‘Earlibelle’, and Arkansas breeding line A-5344 were well suited for once-over mechanical harvesting under Arkansas conditions considering yield, quality, and organoleptic evaluation. Plant population densities in the matted row system used in this study generally had little effect on yield or quality, unless a clone was of low vigor and poor runner plant producer. As harvest date was delayed, quality and useable yield often decreased. However, a minimum of a 6 day harvest period for mechanical harvesting existed for the cultivars tested. The results of this study indicate that once-over mechanical harvesting of strawberries is feasible when the proper cultivar is grown on properly shaped beds with good cultural practices and adequate postharvest handling procedures.

Open Access

Abstract

Multiple preharvest applications of CaCl2 at 1000, 2000, or 4000 ppm (actual Ca) had little effect on fruit firmness of blackberry (Rubus sp.) at harvest. After a 24 hour holding, fruit from the first harvest was firmer if treated with Ca. Preharvest Ca treatments reduced soluble solids accumulation in fruit and 4000 ppm caused foliar damage. Ca had little effect on acidity or color at harvest, but reduced the rate of ripening during postharvest holding.

Open Access

Abstract

Economic efficiencies were greatest in peak sales periods in surveyed floricultural firms selling both to retail florists, and mass markets. Efficiency decreased in intermediate and slack sales periods. About the same procedures were followed in each time period, but sales were reduced in intermediate, and slack periods. Surveyed firms selling to mass markets sold bedding plants during peak periods which required no variable labor or capital marketing inputs; thus, they were more technically efficient than firms selling to retail florists during the peak period. Economies of size were found in the retail florist channel but not in the mass market channel. Maximum economic efficiency was reached at a smaller size by firms selling to mass markets, indicating that the mass market channel was more competitive in the marketing function than was the retail florist channel. Large differences in technical efficiency were found within groups, indicating that increased profit could be made by the least efficient firms adopting the efficient technology of the most efficient firms within the same group. Within groups, the most efficient firms utilized more fully their fixed inputs than did the least efficient, and were thus able to expend a reduced percentage of sales on variable inputs. A persistant problem for the least efficient firms, especially during slack periods, was a delivery cost larger than that of the most efficient firms resulting from an increase in distance and number of stops.

Open Access

Abstract

Four of 7 strawberry (Fragaria X ananassa Duch.) clones tested did not benefit in total yield from 1 or 2 hand pickings prior to once-over machine harvest. Four of the clones could be hand picked once without a significant reduction in machine harvested yields. Two clones were low yielding regardless of the harvest method. ‘Sunrise’, a high once-over yielding clone, increased in total yield with hand harvesting but fruit were soft and poorly colored and lacked good field holding and in-plant handling capabilities. ‘Cardinal’ represented a clone with fruit quality and a ripening pattern suitable to a combination of hand and machine harvesting. Fruit remaining on the plants after 1 or 2 hand harvests had a higher percentage of ripe fruit in the once-over harvest than machine harvested fruit not preceded by a hand harvest. The composite once-over machine harvested fruit after 1 or 2 hand pickings showed the same or higher soluble solids, shear press firmness, puree viscosity and color intensity as hand harvested fruit. In clones with high quality fruit, the presence of immature fruit in the onceover harvest did not detract from puree color or flavor acceptability. Selection A-5344 possessed both yield and quality characteristics desired for a completely mechanized harvest for processing.

Open Access