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The northern fringe of the Gulf of Mexico has an excellent climate for growing high-quality satsumas that are available in U.S. retail chain stores before most other citrus. In part because of high fruit quality, satsuma mandarin production grew into a major industry in Alabama, Louisiana, Mississippi, and the panhandle of Florida in the early 1900s. Freeze protection measures were not sufficient to prevent devastation of the industry by severe freezes. For the period encompassing the late 1900s, freeze risk was estimated using a mathematical approach that determined killing temperature based on air temperature. Freeze injury was determined to occur 1 out of every 4 years on average, although the freezes tended to come in clusters that have as yet not been correlated with long-term climate patterns. Within-tree microsprinkler irrigation, which was not available in the early 1900s, has been shown to reduce the severity of injury. Within-tree microsprinkler irrigation allows full production the year after the freeze, whereas unprotected trees must be grown from the base or replanted. The northerly geographical limit in the southeastern United States whereby satsumas can be successfully grown commercially is currently not known. Methods of protecting the entire tree, including overtree microsprinkler irrigation plus windbreaks and high tunnel houses, are being evaluated. More cold-tolerant satsuma cultivars have been selected, but they reduce freeze risk by at most 2 °C in this region compared with current commercial cultivars. Genetic modification is one possible mechanism for improving cold tolerance sufficiently to reduce freeze risk similar to that of the citrus industry in Florida.

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Satsuma mandarin is presently the primary citrus crop for citrus growers in south Alabama, south Mississippi, and for certain new plantings in northwest Florida. Current growth in satsuma mandarin hectarage in Alabama is similar to the historical hectarage expansion that occurred during decades or clusters of years with a low incidence of lethal, freezing temperatures. Commercial groves currently range in size from 100 to 2000 trees and use various freeze protection strategies, including wind breaks, overstory frost protection with pine or pecan trees, under-tree and scaffold branch irrigation, and high tunnel polyethylene-covered greenhouses. The various methods of freeze protection require adjustments in cultural management practices, including spacing, pruning, irrigation, and fertilization. The primary rootstock used and recommended for its cold-hardiness and edaphic adaptation is Poncirus trifoliata. Some groves use ‘Swingle’ citrumelo, mainly because it is grown and propagated in Louisiana, where it is valued for its higher salt tolerance. ‘Owari’ was the original cultivar introduced to the United States from Japan in the late 19th century and is still the main cultivar in Alabama today, although earlier maturing cultivars, including ‘Brown Select’, ‘Early St. Ann’, and ‘LA Early’, are being introduced to extend the marketing season. Cultivars from Japan and China, including ‘Okitsu Wase’, ‘Miyagawa Wase’, and ‘Xie Shan’, are currently being evaluated for suitability in the region. Three general methods of culture with regard to spacing and pruning are discussed. Nitrogen application rates are typically low to moderate, yet leaf nitrogen levels surveyed in groves in 2005 were generally optimal or high with respect to published sufficiency levels for mature citrus in Florida.

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For most grocery stores, external quality standards require that premium mandarins be orange, unblemished, and large. Thus, for consumers to differentiate among the premium mandarins on any dimension other than price, additional positioning attributes must be evaluated. This study considered consumer preferences for price ($2.18/kg, $4.39/kg, or $15.41/kg), packaging (1.36 kg of loose fruit, 1.36-kg bag, 2.27-kg box, or 0.23-kg clamshell with peeled fruit sections), type of mandarin (clementine, satsuma, tangerine), shelf life from the day of purchase (3, 14, or 31 days), and vitamin C content (with or without a label stating high in vitamin C). A conjoint survey was conducted in four grocery stores located in Birmingham and Montgomery, Ala. In total, 289 respondents used a 7-point intention-to-buy scale to rate photographs of 16 product profiles. Six market segments were identified, based on maximal similarity of preferences within each segment and maximal differences between segments. A simulation was conducted of the effect that an introduction of peeled-and-sectioned satsumas would have on the market share and gross revenue of other mandarins. This product showed great potential, but should be offered in a product mix that includes the loose form as well. Labeling for vitamin C was preferred by all segments, but did not contribute much to the intention-to-buy rating. Awareness and recognition of satsumas needs to be addressed in promotional campaigns. The longest shelf life was the first choice of almost half the respondents.

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Lack of winter chilling can be a serious problem for commercial peach producers in the Southeast. Studies were conducted over 3 years (1989-91) to evaluate the effects of hydrogen cyanamide (Dormex-SKW) on replacing lack of winter chilling on 7 varieties of peaches. This study specifically reports on the effects of hydrogen cyanamide on 'Ruston Red' peach, a 850-hour variety.

Results from 1990 studies using whole tree sprays to the point of runoff indicated a problem with the efficacy and phytotoxicity. In 1991, a combination of hydrogen cyanamide (49%) rates (0, 0.5, 1, 2, and 4% V/V) and timings (0, 25, 50 and 75% of chilling level) were evaluated using 7-year-old 'Ruston Red' peach trees. Only 590 hours of chilling at 7.3°C and lower were accumulated at this site. Rates of 0.5 75% (actually only 70%) chilling level induced full cropping while control trees produced practically no crop.

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Lack of winter chilling periodically becomes a serious problem for commercial peach producers in the Southeast, especially along and near the Gulf Coast areas. Studies were conducted over 3 years (1989-1991) to evaluate the effects of hydrogen cyanamide (Dormex - SKW) on replacing lack of winter chilling in 7 varieties of peaches.

Initial findings using whole tree sprays to point of runoff indicated a problem with efficacy and phytotoxicity. A combination of hydrogen cyanamide rates (0, .5, 1, 2 and 4% V/V) and timings (0, 25, 50 and 75% of chilling level) were evaluated in 1991. Rates above 2% were phytotoxic. Rates of 0.5 to 1.0% were safe and effective when applied at 75% chilling.

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This article reviews the results of 5 years of marketing research on Alabama satsumas and makes recommendations for future progress. Although there are only 28 ha of satsuma orchards in production in Alabama at this time, there are a number of encouraging developments that suggest considerable potential for expanding the industry such as microsprinkler freeze protection, new early-maturing and cold-tolerant varieties, contract sales through the Farm-to-School Program, and rising demand for premium mandarins. Prospects for the industry marketing effort are considered from the perspectives of analyzing marketing opportunities, identifying market segments, selecting attractive target markets, designing marketing strategies, planning marketing programs, and managing the continuing marketing effort. A number of distinct consumer segments have been identified, including one that prefers fruit that is still slightly green and another that prefers a longer shelf life. A peeled-and-sectioned product also appears to have considerable market potential. Name recognition is still a problem as is insipid flavor from fruit that is marketed beyond its optimal ripeness. Needs for the future are detailed and include the needs of the commodity (freeze protection and expanded acreage), the needs of the market (consistency and quality), the needs of the product (quality standards and consumer awareness), the need for and the needs of a brand (recognition and equity potential), the needs of an organization (cooperation and leadership), and the needs of the industry (processes for building equity, forestalling competition, reducing supply shocks, and attracting investment).

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Net photosynthesis (Pn), stomatal conductance (Cs), transpiration (Ts), and water use efficiency (WUE) were determined with a LICOR 6250 Portable Photosynthesis System for four cultivars of Acer rubrum L. under light intensities ranging from 300 to 1950 μmol·m-2·sec-1 photosynthetically active radiation (PAR). As PAR increased, there was a linear relationship for Pn, Cs, and Ts for the cultivars `Franksred' (Red Sunset TM) and `October Glory'. In contrast, the cultivars `Schlesingeri' and `Northwood' had quadratic relationships for Pn and Cs as PAR increased. Ts was quadratic for `Schlesingeri' and had a linear relationship for `Northwood.' WUE was quadratic for each of the four cultivars.

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The relationship between fruit maturation and accumulation of hydrogen peroxide (H2 O2), lipid peroxidation, ethylene (C2 H4) production, antioxidant activity (hydrophilic, lipophilic and total) and the antioxidant enzyme ascorbate peroxidase (APX, EC 1.11.1.11) in fruit pericarp tissue of `Chandler' (Fragaria × ananassa Duch.) strawberry were measured. `Chandler' fruit pericarp maturation and ripening were accompanied by a decline in H2 O2 content early in fruit development followed by a rapid accumulation. An increase in membrane lipid peroxidation (thiobarbituric acid reactive substances, TBARS) coincided with accumulation of H2 O2, which preceded a rise in C2 H4 production. In general, antioxidant activity declined as fruit matured and ripened. APX enzyme activity increased by 2-fold and peaked at the pink stage of development and then gradually declined with ripening. H2 O2 may serve as a signal molecule to initiate the cascade of oxidative processes during maturation and ripening. APX enzyme activity during maturation and ripening was not substantial and thus, may not have a role in alleviating accumulation of H2 O2 and subsequent events related to oxidative senescence in fruit pericarp. To our knowledge, this is the first study to present fractionated antioxidant activities (HAA, LAA and TAA) from strawberry pericarp as assessed by the ABTS∼+ radical cation assay. A fundamental understanding of the mechanisms involved in the senescent related-oxidative changes during strawberry fruit ontogeny in relation to quality and nutrition is discussed.

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Changes in fruit quality attributes and antioxidative properties from six cultivars of thornless blackberries (Rubus sp.) (`Apache', `Arapaho', `Chester', `Loch Ness', `Navaho', and `Triple Crown') during four different ripening stages (red, mottled, shiny-black, and dull-black) were determined under Alabama growing conditions. Berry fruit samples were evaluated for pH, titratable acidity, total soluble solids, TSS/TA ratio, soluble sugars, vitamin C (reduced, oxidized and total), and antioxidant capacity (measured as trolox equivalent antioxidant capacity, TEAC). Significant variation among cultivars were noted in fruit quality attributes and antioxidative properties, which were influenced by maturity at harvest. An increase in fruit pH concomitant with a decline in titratable acidity (TA) was observed during ripening for all cultivars. Total soluble solids (TSS) values increased from 5.7% to 11.6%, with associated TSS/TA ratio values ranging from 11.92 to 63.56 in ripening fruit. Highest reducing and total sugar content were contained in dull-black fruit. Vitamin C content either declined or remained unchanged with ripening, and the pattern was dependent on cultivar, maturity at harvest and form determined. In general, antioxidant activity declined between red and dull-black ripening stages. The results suggest that the TSS/TA ratio may provide the best maturity index in determining optimal eating quality and antioxidant capacity in terms of TEAC value the best indicator of optimal nutritional quality as influenced by maturity at harvest.

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The health status of Alabama's population ranks above the national average with respect to the prevalence of poor overall health indicators. Consumer knowledge of the health benefits of consumption of fresh fruit is lacking. The compositional and nutritional qualities of fruit are highly variable among states with different climate, soil, and other environmental conditions. Compositional and nutritional data of fresh fruit that reflect Alabama growing conditions is limited. Commercially fully ripened kiwi fruit (Actinidia deliciosa cvs. Fitzgerald and Hayward) were compared for fruit quality (pH, TA, °Brix, °Brix/TA, and soluble sugars), and antioxidant properties; Vitamin C (reduced, oxidized, and total), Vitamin C Equivalent Antioxidant Capacity (VCEAC), ferric reducing antioxidant power (FRAP), DPPH radical scavenging activity, total phenolics, and flavonoids. In general, `Fitzgerald' ranked higher in overall fruit quality and antioxidant properties when compared to `Hayward'.

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