Search Results
Abstract
Two experiments were conducted to test the hypothesis that plants in the vegetative state would not succumb as rapidly to low light intensities if they had no phosphorous available as the resulting restriction in growth would permit stored photosynthate to be available for plant maintenance. The first used Peperomia obtusifolia ‘Variegata’ as the test plant. The rooted cuttings were received on December 22, 1965, and potted in propagator’s sand. They were grown in sand cultures to the surface of which a mineral nutrient solution was applied daily with the leachate allowed to drain away. The mineral nutrient solution contained in millimoles per liter, 5, 6, 1, and 1 of Ca(NO3)2, KNO3, KH2PO4, and Mg-SO4, respectively. Two ppm of Fe were added as a chelate (Fe 138) and trace elements were added as usual for a solution culture according to the recipe of Hoagland.
Perennial ryegrass (Lolium perenne) has traditionally been used to overseed warm-season grasses in the southern U.S. when warm-season sods are dormant due to chilling temperatures. In this study we investigated overseeding turf-type annual ryegrass (two cultivars of L. multiflorum and one cultivar of L. rigidum) and chewing fescue (Festuca rubra var. commutata) as well as perennial ryegrass onto a warm-season common bermudagrass (Cynodon dactylon) sod. The objective was to compare turf quality, turf color, and transition date of turf-type annuals with perennials and other cool-season grasses. Results for turf quality indicated that the annual ryegrass cultivars `Axcella' and `Panterra' (L. multiflorum) compared very well with perennials through March; however, in April and May, perennials were superior for quality. `Hardtop' fine fescue is a hard fescue (F. ovina var. duriuscula). It was inferior to the annuals for turf quality from December to April when the annuals began to die. For turf color, annuals had a lower rating compared to dark green perennials such as `Premier II', `Derby Supreme', or `Allstar'. `Panterra' was darker compared to `Axcella' in March and April. Chewing fescue was intermediate in color compared to annuals and perennials. For turf height, `Axcella' was taller than `Panterra', which were both taller than the perennials, and the fine fescues were shorter than the perennials. For transition in the spring, the annuals had a shorter transition and died about 1 month earlier than the perennials. `Transtar' (L. rigidum) had an earlier transition than the other annuals. The perennials tended to have a longer transition period. The fescues had a very long transition period and were similar to the perennials.
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.
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.
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.
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.
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.
Abstract
Butanedioic acid mono-(2,2-dimethylhydrazide) (daminozide) increased the red color and anthocyanin content of fresh and processed sweet cherries (Prunus avium L.). Daminozide had no effect on the USDA color grade for processed dark sweet cherries but reduced the USDA character of processed dark sweet cherries and increased drained weight losses regardless of cultivar. The use of daminozide on light sweet cherries resulted in reduced USDA color grade for the processed product. A 2-week delay in harvest also increased red color and anthocyanin content of sweet cherries, and increased the USDA color grade of the processed ‘Bing’, ‘Chinook’, and ‘Rainier’ cherries. In addition, it reduced the USDA character grade of processed ‘Chinook’ but not of ‘Bing’ and ‘Rainier’ sweet cherries.
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.
Satsuma mandarins (Citrus unshiu) have been produced intermittently along the Gulf Coast for over a century. However, very little is known about the market potential for this citrus fruit in today's consumer markets. This study evaluated consumer preferences for seven external attributes over a range of levels: price ($1.07, $2.18, or $4.39/kg), color (green-yellow, yellow-orange, or orange), size (5.08, 6.35, or 7.62 cm in diameter), seediness (0, 3, or 7 seeds), blemishes (0, 1.91, or 3 cm in diameter), production region label (Alabama or U.S.A.), and organic production (yes or no). Consumers from grocery stores in nine cities in Alabama and Georgia were asked to evaluate 20 photographs of various combinations of these attribute levels using a seven-point intention-to-buy scale. 605 useable surveys were collected and a conjoint analysis was conducted to determine the strength of preference for the attribute levels and the relative importance for attributes. Three consumer segments were identified by cluster analysis of strengths of preferences: the no-blemish segment (37% of sample), the price-sensitive segment (23% of sample), and the no-seeds segment (41% of sample). A multinomial logit analysis identified several demographic, socioeconomic, and usage variables as significant determinants of segment membership.