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Ibrahim I. Tahir and Hilde Nybom

A series of pre- and post-harvest experiments were conducted to enhance apple tree productivity and improve fruit quality and storage life by altering production system and post-harvest treatments in an organic orchard. Increasing the light distribution and carbohydrate uptake (summer pruning and covering the orchard ground with reflective textile) improved tree productivity, fruit color, content of anthocyanin, ascorbic acid, and total phenolic compounds and reduced incidence of fungal storage diseases. Optimal harvesting time could be determined from the starch index in some cultivars, whereas the Streif index [firmness (soluble solids concentration × starch hydrolysis score)−1] was more accurate for other cultivars. In yet others, titratable acidity and flesh firmness also produced important information. By contrast, soluble solids concentration and skin color are not useful as a result of their sensitivity to weather conditions and light intensity. Post-harvest fruit treatment with hot water (46 °C for 120 seconds) decreased fungal decay during storage in two cultivars, whereas spraying the fruit with 10% ethanol decreased fungal decay in all investigated cultivars. Optimization of storage conditions [cultivar-specific controlled atmosphere (CA) and ultra-low oxygen (ULO) storage procedures] maintained fruit quality and reduced the amount of fungal decay.

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Esmaeil Fallahi, Bahar Fallahi, Bahman Shafii, and Zabihollah Zamani

‘Fuji’ apple (Malus ×domestica Borkh) has gained popularity in the past decades, but poor color of this apple mandates introduction of new strains. To pursue this objective, long-term effects of five ‘Fuji’ apple strains, consisting of ‘Autumn Rose’, ‘Desert Rose’, ‘Myra’, ‘September Wonder’, and ‘Top Export’ on RN 29 rootstock on fruit yield (in 7 years) and harvest time quality attributes (in 6 years) under climate conditions of southwest Idaho were studied during 2004–10. Fruit of ‘September Wonder Fuji’ trees were larger than those of other strains in 5 of 6 years. The type or pattern of peel color among the “low-coloring” and “high-coloring” strains varied widely. Fruits of ‘Autumn Rose Fuji’, ‘Myra Fuji’, and ‘Top Export Fuji’ always had less but ‘September Wonder Fuji’ and ‘Desert Rose Fuji’ had more red color. Fruit of ‘September Wonder Fuji’ had lower firmness but higher starch degradation pattern (SDP) than those of other strains every year as a result of the earlier maturity of this strain. Fruit of ‘Top Export Fuji’ had the lowest SDP among all strains. Fruit of ‘Autumn Rose Fuji’ tended to have lower soluble solids concentration in 3 of 6 years of this study. Considering all yield and quality attributes at harvest, ‘September Wonder’ was a great choice for an early-maturing and ‘Desert Rose’ was suitable for a late-maturing ‘Fuji’ strain. ‘Myra Fuji’ was particularly desirable for its attractive pink color that resembles bagged ‘Fuji’ without the expensive cost of labor associated with bagging.

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H.C. Wien and A.D. Turner

The blossom-end scarring of tomato fruit caused by exposure of the plant to cool weather during ovary formation, commonly termed catfacing, can also be induced by GA3 foliar sprays. To determine if GA3 treatment could serve as a cultivar screening tool to identify lines susceptible to the disorder, we compared the catfacing incidence in 14 fresh-market tomato cultivars after GAS sprays and in nontreated controls in two field experiments. In 1 year, removal of the plant's apex was also imposed. GA3 sprays (22 μm twice, applied 1 week apart to tomato seedlings ≈5 weeks old) increased catfacing incidence in both years and accentuated cultivar differences in the disorder. Topping did not increase catfacing significantly. The cultivars Valerie, Sunrise, and Basketvee were least affected by catfacing in the experiments, while `Starfire', `New Yorker', and `Olympic' had the highest percentage of catfaced fruit. The GA3 screening method shows promise for identifying cultivar differences in susceptibility to blossom-end scarring. Chemical name used: gibberellic acid (GA3).

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Ahmed Mahhou and Frank G. Dennis Jr.

Morocco ranks fifth among the nations of the world in almond (Prunus dulcis L.) production, and contains many zones where climatic conditions are ideal for this species. Seedling trees are responsible for more than half the total production, although grafted trees are usually much more productive per hectare. A large seedling population represents an important gene pool, both for a breeding program and for selection of superior genotypes adapted to Moroccan conditions.

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Frank Kappel, Robert Fisher-Fleming, and Eugene J. Hogue

The relationship between the objective assessment of sensory attributes or fruit characteristics of pear (Pyrus communis L.) fruit and the corresponding consumer or sensory panel rating was studied. Optimum fruit diameter was between 6 and 7.5 cm. Some fruit were judged to be too large. Fruit with a bright yellow skin were rated ideal, whereas green or red skin was rated less favorably. A pyriform shape with a length: diameter ratio range of 1.44 to 1.48 was optimum. Round fruit or very elongated fruit were considered undesirable. Perceived firmness increased linearly as the measured firmness increased, with the optimum firmness at 27 to 30 N (using an 11.1-mm penetrometer tip). Perceived juiciness was negatively, linearly related to measured firmness. Ideal firmness for an ideal juiciness rating was 18 to 22 N. Acceptable soluble solids concentrations (SSC) varied with the study year, but ranged between 13.6% and 17.2%. The sweet/sour balance (ratio of SSC: titratable acidity) was a useful indicator of fruit quality.

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D.S. Gardner and J.A. Taylor

In 1992, a cultivar trial was initiated in Columbus, Ohio to evaluate differences in establishment and long-term performance of cultivars of tall fescue (Festuca arundinacea), creeping red fescue (F. rubra), chewings fescue (F. rubra ssp. fallax), hard fescue (F. brevipila), kentucky bluegrass (Poa pratensis), rough bluegrass (P. trivialis), and perennial ryegrass (Lolium perenne) under low maintenance conditions in a shaded environment. Fertilizer and supplemental irrigation were applied until 1994 to establish the grasses, after which no supplemental irrigation, or pesticides were applied and fertilizer rates were reduced to 48.8 kg·ha-1 (1 lb/1000 ft2) of N per year. Percentage cover and overall quality data were collected in 2000 and compared with data collected in 1994. Initial establishment success does not appear to be a good predictor of long-term success of a cultivar in a shaded environment. There was some variability in cultivar performance under shade within a given turfgrass species. The tall fescue cultivars, as a group, had the highest overall quality and percentage cover under shade, followed by the fine fescues, kentucky bluegrass, rough bluegrass, and perennial ryegrass cultivars.

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Sogo Nishio, Masahiko Yamada, Norio Takada, Hidenori Kato, Noriyuki Onoue, Yutaka Sawamura, and Toshihiro Saito

inheritance of PS and II and the associated selection efficiency. However, breeders have recorded the performance data for those traits of cultivars/selections for many years in the NIFTS breeding program. Environmental variance in an orchard comprises the

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Takashi Akagi, Yumi Takeda, Keizo Yonemori, Ayako Ikegami, Atsushi Kono, Masahiko Yamada, and Shinya Kanzaki

breeding of PCNA-type persimmons, the hexaploid inheritance of the AST / ast allele restricts the breeder in intercrossing PCNA-type cultivars, selections, or both. When some non-PCNA-type cultivars were used as parents, PCNA offspring could only be

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Mark A. Mikel

of this era were developed consisted of: A) within cultivar selection; B) two-parent “cultivar A × cultivar B”; C) three-parent “(A × B) × C”; D) four or more parents; E) backcross one “(A × B) × B”; F) backcross two or greater; and G) cross involving

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Stephen J. Stringer, Donna A. Marshall, Blair J. Sampson, and James M. Spiers

. Cultivar selection decisions require an understanding of several important factors ranging from pollination biology to end-use markets. The biology of muscadine grape pollination is of importance because currently grown cultivars are hermaphroditic