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Jim E. Wyatt

Removing a portion of the foliage of zucchini squash without reducing yield would increase the efficiency of mechanical harvest since less plant material would be passed through the harvester. Pruning 50% of the leaves and petioles at either first or second harvest had no effect on third harvest fruit yield. Primary or secondary fruit growth rates were not affected by leaf removal. Presence of a primary fruit reduced the number of secondary fruit developing to marketable size but the rate of secondary fruit development was similar on plants with one, two, or three fruit. The maximum fruit to develop at one time in this planting was two per plant. Following one or two hand-harvests of zucchini squash, mechanical harvest efficiency will be increased after removal of 50% of the leaves and maturation of two marketable fruit per plant.

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Isabelle Grechi, Nadine Hilgert, Michel Génard, and Françoise Lescourret

linked to crop models and able to predict the refractometric index of peach fruit at harvest under a wide range of growing conditions. This model was partly based on the model of Quilot et al. (2004) , which describes the variation of total sugar content

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W. Kalt and J. McDonald

Fruit composition can be affected by genetic and environmental factors during development and ripening. Red-ripe strawberries were harvested at regular intervals during the harvest season to determine how early or later ripening fruit may vary in composition. The cultivars `Cavendish', `Honoeye', and `Kent' were harvested twice weekly over a 3-week period and FW, %DW, and sugar, acid, and anthocyanin pigment content was measured. The study was repeated for 2 years. Fresh fruit weight declined over the harvest period, while the %DW increased in all cultivars. Although the content of sucrose and glucose (mg/g DW) did not vary among the harvest dates, their content was different among the cultivars. Citric and malic acid content (mg/g DW) was lower in the later harvests, although their content was similar among the cultivars. Total anthocyanin content increased and then declined during the harvest season. Pelargonidin 3-glucoside, the major strawberry anthocyanin, was highest in `Honoeye', while cyanidin 3-glucoside content was similar among the three cultivars.

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Esmaeil Fallahi, Bahar Fallahi, Bahman Shafii, and Mohammad E. Amiri

peaches into five categories, according to their period between full bloom and harvest: 1) “very early cultivars,” which have less than 65 d from full bloom to harvest, 2) “early cultivars,” which have 66 to 90 d from full bloom to harvest, 3) “mid

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Bao-Cheng Ma, Wan-Li Tang, Li-Yan Ma, Ling-Ling Li, Lu-Bin Zhang, Shi-Jiang Zhu, Chuxiong Zhuang, and Donald Irving

and MeJA to determine the possible relationship between chitinase gene expression and resistance to anthracnose disease in harvested bananas during development from the green to the ripe stage. We also tested physical (heat) and chemical (H 2 O 2 - and

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Juan Carlos Melgar, Jill M. Dunlop, L. Gene Albrigo, and James P. Syvertsen

Successful mechanical harvesting of perennial fruit crops requires efficient, economical harvesting systems that do not shorten a tree's productive life or diminish fruit quality relative to hand harvesting ( Roka et al., 2000 ). Although most of

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Don C. Elfving, Stephen R. Drake, A. Nathan Reed, and Dwayne B. Visser

to apple fruit after harvest by fumigating the fruit in a closed space with 1-MCP, which is a gas at normal temperature and pressure ( Blankenship and Dole, 2003 ; Prange and DeLong, 2003 ; Watkins, 2006 ). In apples, 1-MCP inhibits perception of

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M. Moriondo, M. Bindi, and T. Sinclair

Crop growth simulation models have been mainly developed to simulate final yield reliably. Thus, a main challenge in these models is the definition of a stable method for expressing the growth of harvested organs (e.g., fruit, seed, tuber, etc.). Generally, two approaches have been used: growth rate analysis of harvested organs [yield growth rate (YGR)] and analysis of harvest index (HI) increase over time (dHI/dt). This work aims to: 1) examine whether YGR and dHI/dt increase linearly over much of growing period, and 2) compare the two growth indices in terms of stability across a number of treatments, in order to identify which is the best indicator of harvest-organ growth. This analysis has already been performed for a large number of field crops, including wheat (Triticum aestivum L.), sunflower (Helianthus annuus L.), soybean [Glycine max L. (Merr.)], and pea (Pisum sativum L.), but it has never been attempted in crops where final yield is not simply seeds. In this study, YGR and dHI/dt performances for tomato (Lycopersicum esculentum Mill.), potato (Solanum tuberosum L.), and eggplant (Solanum melongena L.) were compared using 21, 18, and 4 datasets, respectively. Results indicated that both descriptors of harvest-organ growth increased linearly for most of the growth period, whilst the comparison among the two variables in terms of stability showed that, although a direct statistical test failed, dHI/dt was more suitable to describe harvest-organ growth (smaller coefficient of variability) under a large range of crop management conditions (e.g., irrigation, sowing date, planting density, and water salt concentration).

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Dale E. Marshall

For over 86 years producers, processors, engineers, and equipment manufacturers have attempted to mechanize the harvest of asparagus. Over 60 U.S. patents have been issued. Probably the most sophisticated harvester tested was started in 1987 by Edgells Birdseye, Cowra, Australia. After successful field tests of the 3-row, selective (fiber optic), harvester for flat-bed green asparagus used in canning, 3 more were built at a cost of $US 4.5 million, and harvested 500 acres until 1991 when the company ceased canning. Recovery was 30 to 80% with 50% being typical. Wollogong University in Australia is now researching a selective (fiber optic), harvester for flat-bed green asparagus. It utilizes multiple side-by-side 3 in. wide by 24 in. dia. rubber gripper discs which rotate at ground speed. No harvester prototype has been commercially acceptable to the asparagus industry due to poor selectivity, low overall recovery (low yield relative to hand harvest), mechanical damage to spears, low field capacity per harvester, or overall harvesting costs that exceed those for hand harvesting. The reality may be that asparagus production will cease in the traditional geographical areas where growing costs and labor costs are high, although niche fresh markets may help some growers survive.

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Travis Robert Alexander, Jaqueline King, Edward Scheenstra, and Carol A. Miles

). In the United Kingdom, which is the world’s largest producer and consumer of cider, growers have minimized cost of production by exclusively harvesting cider fruit by machine ( National Association of Cider Makers, 2010 ). Mechanized harvest systems