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Datil hot pepper (Capsicum chinense) has potential for increased production due to its unique, spicy flavor and aroma. However, few reports have been published related to postharvest handling characteristics. The purpose of this study was to determine the effect of harvest maturity on fruit quality under simulated commercial storage conditions. ‘Wanda’ datil pepper plants were grown hydroponically under protected culture. Fruit were harvested at yellow and orange maturity stages, placed in vented clamshell containers, and stored at 2, 7, or 10 °C for 21 days. Peppers harvested at yellow stage maintained greater quality than orange peppers during storage at all temperatures. Marketable fruit after 21 days for peppers harvested at the yellow stage was 94% (2 °C), 88% (7 °C), and 91% (10 °C); that for orange-stage peppers was 68%, 74%, and 82% for the same respective temperatures. No chilling injury (CI) symptoms were observed in these tests. Initial pepper moisture content was 90%, decreasing only slightly during 21 days of storage; weight loss ranged from 2% to 8%. Soluble solids content (SSC) was greater for peppers harvested at the orange stage (9.5%) than for those at yellow stage (7.8%). Neither harvest maturity nor storage temperature affected total titratable acidity (TTA; 0.13%) or pH (5.3). Respiration rate varied with temperature but not by harvest maturity and ranged from 12 to 25 mg·kg−1 per hour after 8 days of storage. Peppers harvested orange contained double the amount of total carotenoids as yellow fruit. Carotenoid content for yellow and orange peppers was 58 and 122 µg·g−1, respectively. Capsaicinoid content ranged from 1810 to 4440 µg·g−1 and was slightly greater for orange-harvested peppers. Datil peppers harvested at the yellow stage and stored in vented clamshell containers had better quality than peppers harvested at the orange stage after 21 days at 2 °C.

The 2004 hurricane season proved to be one of Florida's worst. The four hurricanes (Charley, Francis, Ivan, and Jeanne) caused over $2 billion in total agricultural loss. In response, the federal government appropriated $13 billion for emergency assistance, of which Florida received a half billion dollars for agricultural disaster assistance. Many of Florida's producers were eligible for up to $80,000 in aid. Among those who tried but failed to qualify for this aid were greenhouse vegetable producers. Although the greenhouse vegetable industry in Florida is small, it is expanding and the present growers suffered millions of dollars in damages from the hurricanes in 2004. A survey was conducted in March, 2005 to assess both hurricane damages in 2004 and the present status of the greenhouse vegetable industry in Florida. This document is HS1021, one of a series of the Horticultural Sciences Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date August 8, 2005.

The strawberry, Fragaria x ananassa, is an important small fruit crop in Florida. The sunshine state leads the southeastern U.S. in strawberry production and ranks second to California nationwide. The mild weather of Florida's fall and winter seasons sustain the nation's second largest strawberry production. These conditions, unfortunately, are also suitable for several arthropod pests to multiply and feed on the crop. Strawberry plants are quickly established two weeks after the transplanting irrigation is turned off. This is the time growers must begin to scout their fields at least once a week to assess the status of pests, such as spider mites, cyclamen mites, lepidopterous larvae, aphids, thrips, and sap beetles. The ability to recognize these pests, their damage, and their natural enemies is important in determining the best control methods for each situation. Keep in mind that miticide or insecticide choices are limited if you participate in a biological control program. This document is HS1018, one of a series of the Horticultural Sciences Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Publication date: July 2005.

Diagnostic structural features for competence to form shoots were tested among sweet potato embryos by combining morphological image capture (using a computer vision system) with anatomical analyses (using light microscopy). Five major morphological variants (`perfect', `near perfect', `limited/no meristematic activity', `disrupted internal anatomy', and `proliferating') were identified among torpedo- and cotyledonary-stage embryos. Among these, only the first two were found to be competent for conversion into plantlets. Lack of organized shoot development in somatic embryos of sweet potato was associated with the following abnormalities: lack of an organized apical meristem, sparcity of dividing cells in the apical region, flattened apical meristem, and multiple meristemoids and/or diffuse meristematic activity throughout the embryo. Diagnostic separation of most shoot-forming and non-shoot-forming torpedo and cotyledonary embryo variants was achieved.

Apical and axial shoot tips of sweet potato were cultured to produce somatic embryos that mature and develop into plants in basal nutrient medium. However, the lack of high regeneration efficiency is an impediment to the use of somatic embryos to produce synthetic seeds. Conversion experiments with mature embryos over a 20-day period revealed that 80-90% of the embryos formed roots but only 40-50% formed shoots. Using computer vision and canonical or Fisher discriminant function (CDA) analysis along with conversion results, it was possible to correctly classify competent embryos 40-50% of the time based on size features, 50-60% of the time based on shape features, and 55-60% of the time based on color features. Non-competent embryos were correctly classified 65-75%, 55-60%, and 70-75% of the time based on size, shape, and color, respectively. These results can be used effectively to identify and select competent embryos for improved regeneration efficiency.

The timing of nitrogen (N) fertilizer application has a direct impact on fertilizer use efficiency of potato (Solanum tuberosum L.) and nitrate leaching. The objective of this study was to determine the effect of N fertilizer rate combined with application timing on soil mineral N availability, tuber yield and quality of crisp potato in northeast Florida. Trials were performed on three commercial farms in 2011 and repeated on two farms in 2012. N fertilizer was applied at three different timings: at pre-plant (Npre-pl), at plant emergence (Nemerg) and at tuber initiation (Ntuber init). All seven treatments received a total of 224 kg ha−1 of N, with each treatment differing in the proportion of N supplied at each application timing. N was applied at 0 or 56 kg ha−1 at Npre-pl followed by 0, 56, 112 or 168 kg ha−1 of N applied at Nemerg and 0, 56, 112 or 168 kg ha−1 of N applied at Ntuber init. Treatments were combined in fractional factorial arrangement in a randomized block design with four replicates. Tuber marketable yield ranged from 23.7 to 44.6 Mg ha−1. Total and marketable yields were unaffected by timing or N rate combinations on two out of three farms and tuber quality was mostly unaffected by application timing. Higher yields were obtained when 56 kg ha−1 of N was supplied at pre-plant compared to 0 kg ha−1 of N on only one farm in both years. On the same farm, regardless of the application of 0 or 56 kg ha−1 Npre-pl, the application of 168 kg ha-1 of Nemerg resulted in superior total yields than when 168 kg ha−1 was instead supplied later in the season at Ntuber init. Higher proportions of N at pre-plant and tuber initiation tended to decrease potato tuber size, and a high proportion of N supplied at tuber initiation resulted in lower yield and higher residual soil mineral N at the end of the season.

Knowledge of seasonal nutrient demand is necessary to maximize potato (Solanum tuberosum) yield and profitability while also minimizing the risk of excess fertilizer leaching into waterways. The objective of this study was to determine the effect of the N fertilizer rate and timing of application on the N use efficiency (NUE) and yield of chipping potato ‘FL1867’. This study was conducted with grower collaboration on three commercial farms for two years (2011 and 2012) using subirrigation on course textured soils in Florida. All treatments received 56 kg ha−1 of N as ammonium nitrate applied as a band approximately 40 days before planting (Npre-pl). Liquid urea ammonium nitrate was then band applied at 0, 56, 112, or 168 kg ha−1 at plant emergence (Nemerg) followed by 56 or 112 kg ha−1 applied as a side-dress at tuber initiation stage (Ntuber init). The treatments were arranged in a factorial design with four replicates. The total amount of N fertilizer applied ranged from 112 to 336 kg ha−1. Maximum daily N uptake by the potato crop occurred between 55 and 65 days after planting, coinciding with the onset of the tuber bulking stage. Heavy rainfall prior to planting the 2011 crop reduced soil N availability from pre-plant applied N fertilizer indicating the high susceptibility of that application timing to leaching. Average tuber yield ranged from 25.6 to 47.2 Mg ha −1, with the lowest yields occurring when heavy rainfall close to harvest increased yield loss to decay. While higher Nemerg rates increased soil inorganic N, tuber yield was either not affected by N application or responded quadratically peaking at Nemerg levels between 95 and 125 kg ha−1. N application rates above this range decreased yield and NUE while increasing soil residual N at the end of the season. Plant N uptake and tuber yield did not increase with Ntuber init rate above 56 kg ha−1 and it was associated with lower NUE and also higher residual soil N.

Optimum nitrogen fertilizer management is necessary to maintain sustainable and economical potato (Solanum tuberosum) production. The objective of this study was to determine the effect of N-fertilizer rate and timing of application on plant biomass, tuber marketable yield and quality of chipping potato irrigated by subirrigation. This study was conducted with grower collaboration on three farms for two consecutive years (2011 and 2012). All experimental plots received 56 kg ha−1 of N as ammonium nitrate approximately 40 days before planting, a common grower practice. Nitrogen fertilizer treatments were 0, 56, 112 or 168 kg ha−1 applied at plant emergence (Nemerg) combined with 56 or 112 kg ha−1 of N applied as a sidedress at tuber initiation (Ntuber init). The two years of this study were characterized by low rainfall conditions, reducing the risk of N leaching and runoff. Under these conditions, the N treatments rarely increased potato aboveground biomass. Mean marketable tuber yield across all sites ranged from 19.2 to 39.7 Mg ha−1 with the lowest yield when a large amount of rainfall occurred prior to harvest at one site. Marketable yield responded quadratically to increase N-fertilizer rates applied at plant emergence, with optimum yield calculated at Nemerg rate between 88 and 113 kg ha−1. Applying more than 56 kg ha−1 of N at tuber initiation did not increase marketable yield, tuber specific gravity or tuber quality on any farm in either year. Nitrogen rate treatments above 112 kg ha−1 at emergence, and 56 kg ha−1 at tuber initiation did not improve potato marketable yield or tuber quality. The contribution of 56 kg ha−1 applied at pre-plant to potato yield is still unknown, and may be more beneficial to move this application closer to planting.

Carrot (Daucus carota) seed germination can be erratic or reduced under temperatures above 35ºC. Priming circumvents seed thermoinhibition in several crops, including carrot. The involvement of ethylene in germination at supra-optimal temperatures has been reported in other species, but its role in carrot seed germination has not been examined. The objective of this study was to determine whether priming-mediated improvement in carrot seed germination at high temperature was associated with increased ethylene production. Seeds of two tropical carrot genotypes (Alvorada and Brasília) were incubated over a range of temperatures. 'Brasilia' seeds were primed for 72 hours in aerated PEG solution at 15ºC under light conditions and germination tested at 20 and 35ºC. Seeds of a thermosensitive genotype 'Arrowhead' were primed for 0, 4, 8 and 12 days in aerated PEG 6000 solutions at 15ºC under light conditions. Seeds were incubated at 20 and 35ºC, and ethylene production was measured immediately before visible primary root protrusion. Temperatures above 30ºC decreased seed germination percentage of 'Alvorada' and 'Brasilia'. Priming increased 'Brasilia' seed germination at 35ºC. 'Arrowhead' germinated 96% at 20ºC, and 13% at 35ºC. Seed germination and ethylene production of 'Arrowhead', a thermosensitive genotype, increased in response to increased duration of priming. The results suggest that seed priming circumvents thermoinhibition of carrot seed germination by increasing ethylene production at high temperatures.

The silverleaf whitefly, Bemisia tabaci biotype B (Gennadius) (Hemiptera: Aleyrodidae), is a key pest of tomato (Solanum lycopersicum L.) and other vegetable crops worldwide. To combat this pest, a non-crop banker plant system was evaluated that employs a parasitoid, Encarsia sophia (Girault & Dodd) (Hymenoptera: Aphelinidae) with whitefly, Trialeurodes variabilis (Quaintance) (Hemiptera: Aleyrodidae), as an alternative host for rearing and dispersal of the parasitoid to the target pest. (a) Multi-choice and no-choice greenhouse experiments were conducted to determine host specificity of T. variabilis to papaya (Carica papaya L.) and three vegetable crops including tomato, green bean (Phaseolus vulgaris L.), and cabbage (Brassica oleracea L.). The result showed that papaya was an excellent non-crop banker plant for supporting the non-pest alternative host, T. variabilis, whose adults had a strong specificity to papaya plants for feeding and oviposition in both multi-choice and no-choice tests. (b) The dispersal ability of E. sophia was investigated from papaya banker plants to tomato and green bean plants infested with B. tabaci, as well as to papaya control plants infested with T. variabilis; and (c) the percent parasitism by E. sophia on T. variabilis reared on papaya plants and on B. tabaci infested on tomato plants was also evaluated. These data proved that E. sophia was able to disperse at least 14.5 m away from papaya plants to target tomato, bean or papaya control plants within 48–96 h. Furthermore, E. sophia was a strong parasitoid of both T. variabilis and B. tabaci. There was no significant difference in percent parasitism by E. sophia on T. variabilis (36.2–47.4%) infested on papaya plants or B. tabaci (29–45.9%) on tomato plants. Thus, a novel banker plant system for the potential management of B. tabaci was established using papaya as a non-crop banker plant to support a non-pest alternative host, T. variabilis for maintaining the parasitoid to control B. tabaci. The established banker plant system should provide growers with a new option for long-term control of B. tabaci in greenhouse vegetable production. Ongoing studies on the papaya banker plant system are being performed in commercial greenhouses.

Carrot (Daucus carota L.) seed germination may be erratic or reduced under high temperatures (above 35 °C). Even in tropical genotypes (tolerant to high temperatures during crop development), the negative effects of high temperatures on carrot stand establishment have been observed, especially during summer. The objectives of this study were to characterize commercial carrot cultivars and accession lines for their ability to germinate at high temperature and determine the ethylene production during imbibition at high temperature. Seeds from 34 commercial cultivars and 125 carrot accessions from the North Central Regional Plant Introduction Station were germinated at 25 °C (optimal) and 35 ± 0.5 °C (high) in constant light. Ethylene production during seed imbibition at high temperature was evaluated in some genotypes. Many of the commercial cultivars had reduced germination at 35 °C. ‘XPC-3617’, ‘Alvorada’, ‘Brasilia’, and ‘Esplanada’ had the greatest germination at 35 °C. A greater number of accessions germinated at 35 °C than did the commercial genotypes. The accession PI 319858 germinated 95% at both temperatures and was considered thermotolerant. Six accessions (Ames 7665, Ames 7698, Ames 25031, PI 167082, PI 294637, and PI 319858) germinated above 80% at 35 °C and were also identified as potential sources of thermotolerance. Fifteen other accessions (Ames 7694, Ames 25031, Ames 25036, Ames 25049, Ames 25705, PI 167082, PI 179687, PI 180834, PI 261782, PI 269486, PI 273658, PI 277710, PI 288242, PI 294637, and PI 319858) had thermotolerance ratios of T35/T25 0.85 or greater (where T35 = germination at 35 °C and T25 = germination at 25 °C) and were identified for further testing. The identified thermotolerant genotypes might be useful for carrot seed germination mechanism studies as well as for breeding programs. Ethylene production during seed germination at high temperature was greater in thermotolerant genotypes than in thermosensitive genotypes. High correlations were observed between first germination count at 35 °C and ethylene production, total germination at 35 °C and ethylene production, and thermotolerance ratio and ethylene production.

To investigate thermotolerance in seeds of lettuce (Lactuca sativa L.), primed, nonprimed, or seeds matured at 20/10 and 30/20 °C (day/night on a 12-h photoperiod) were imbibed at 36 °C for various periods and then dissected. Structural changes in seed coverings in front of the radicle tip were observed during germination at high temperature. Thermotolerant genotypes, ‘Everglades’ and PI 251245, were compared with a thermosensitive cultivar, ‘Dark Green Boston’. In all seeds that germinated, regardless of seed maturation temperature or priming, a crack appeared on one side of the cap tissue (constriction of the endosperm membrane near the basal end of the seed) at the micropylar region and the endosperm separated from the integument in front of the radicle tip. Additional changes took place during imbibition in these seeds; the protein bodies in the vacuoles enlarged and gradually depleted, large empty vacuoles formed, the cytoplasm condensed, the endosperm shrank, the endosperm cell wall dissolved and ruptured, and then the radicle elongated toward this ruptured area. The findings suggested that the endosperm layer presented mechanical resistance to germination in seeds that could not germinate at 36 °C. Weakening of this layer was a prerequisite to radicle protrusion at high temperature. Seeds of ‘Dark Green Boston’, ‘Everglades’, and PI 251245 matured at 30/20 °C had greater thermotolerance than those matured at 20/10 °C. Results of the anatomical study indicated that the endosperm cell walls in front of the radicle of seeds matured at 30/20 °C were more readily disrupted and ruptured during imbibition than seeds matured at 20/10 °C, suggesting a reason why these seeds could germinate quickly at supraoptimal temperatures. Similar endosperm structural alterations also were observed in primed seeds. Priming led to rapid and uniform germination, circumventing the inhibitory effects of high temperatures. From anatomical studies conducted to identify and characterize thermotolerance in lettuce seed germination, we observed that genotype, seed maturation temperature, or seed priming had the ability to reduce physical resistance of the endosperm by weakening the cell wall and by depleting stored reserves leading to cell collapse.

The minute broad mite, Polyphagotarsonemus latus (Banks), can cause serious damage to peppers (Capsicum annuum) when infestations occur at early plant developmental stages. A first study was set to evaluate biological control strategies during seedling development. Timing of release of Neoseiulus californicus McGregor, a commercially reared predatory mite, was investigated in scenarios of pest and predator presence to simulate preventive and curative strategies of control. Undamaged seedlings were produced when two predators per seedling were released preventively. Curative control strategies were not effective for producing undamaged or broad mite-free transplants. Further studies were carried to evaluate the effectiveness of N. californicus on pepper seedlings that host a few broad mites and are transplanted into the production greenhouse. N. californicus released at different times and densities, and conventional control methods (micronized-sulfur sprays) were evaluated for pest control, plant damage, and fruit yield. Yields of red fruits from plants with four predators per plant released at any of the release times (a week before, at, or four days after transplanting) or with sulfur sprays were not significantly different from an uninfested control treatment. Releases of two predatory mites per plant led to yields similar to the uninfested control only when introductions were a week before transplanting, while later introductions led to serious plant damage and significantly lower yields. Early broad mite infestations in pepper crops grown in greenhouses might be effectively controlled with N. californicus released at early seedling developmental stages in the nursery and at transplanting in the fruit production greenhouse. INTRODUCTION Infestations of broad mite [Polyphagotarsonemus latus (Banks); (Acari: Tarsonemidae)] initiated at early developmental stages of pepper (Capsicum annuum) can lead to severe plant damage in greenhouses where transplants or fruit are produced (de Coss-Romero and Pena, 1998; Gerson, 1992; Weintraub et al., 2003). Seedlings will appear undamaged when they become infested with the minuscule mite a few days before transplanting but they carry the pest to crops transplanted in greenhouses. Biological control programs initiated at early pepper crop stages are disrupted by multiple sprays of the commonly used pesticides (e.g., sulfur, abamectin, and dicofol). Neoseiulus californicus McGregor (Acari: Phytoseiidae), a predaceous mite released on greenhousegrown vegetables for biological control of two-spotted spider mite [Tetranychus urticae Koch (Acari: Tetranychidae)], has been reported to feed on broad mites as well (Castagnoli and Falchini, 1993; Pena and Osborne, 1996). N. californicus can reproduce when feeding on broad mites (Castagnoli and Falchini, 1993). Preventive releases may provide effective pest management as the predator can remain on plants for short periods when prey is absent (de Courcy Williams et al., 2004). This manuscript presents selected results of research that evaluated the use of N. californicus as a broad mite management Proc. IV IS on Seed, Transplant and Stand Establishment

Eight plant densities (8.8, 9.5, 10.4, 11.4, 17.6, 19.1, 20.8, and 22.9 plants m −2 ) in 2001–2002 and 12 plant densities (8.8, 9.5, 10.4, 11.4, 12.7, 14.3, 17.6, 19.1, 20.8, 22.9, 25.4, and 28.6 plants m −2 ) in 2002–2003 were evaluated on growth and fruit yield of ‘Sweet Charlie’ strawberry ( Fragaria × ananassa Duch.) grown in a passively ventilated greenhouse. Plant densities were derived by varying within-row plant spacings (PS) (17.5 and 35 cm) with between row spacings (RS) (40, 45, 50, 55, 60 and 65 cm). Plants were grown in Polygal ® ‘Hanging Bed-Pack’ troughs filled with pine bark and fertigated with a complete nutrient solution. In 2001–2002, total marketable yield (g plant −1 ) or (no. fruit plant −1 ) were not influenced by RS. In 2002–2003, total marketable yield (g plant −1 ) or (no. fruit plant −1 ) were reduced at 40 cm RS, the narrowest RS used in the experiment. Early (November through January) and total marketable yields (g plant −1 ), crown diameter, and leaf number of plants grown at 35 cm PS were significantly greater than those of plants grown at 17.5 cm RS in both experiments. Total and early marketable yield (kg m −2 ) increased linearly as plant density (plants m −2 ) increased in both experiments. Winter strawberry production in a greenhouse using high plant densities and soilless substrates may be a viable alternative to open-field with methyl bromide fumigation production system.

‘Galia’ (Cucumis melo var. reticulatus L. Naud. cv. Galia) fruit were harvested at the three-quarter slip stage and treated with 1 μL L−1 1-methylcyclopropene (1-MCP) at 20 °C for 24 h. The fruit were processed and stored as fresh-cut cubes and intact fruit for 10 d at 5 °C. Ethylene production of fresh-cut cubes was approximately 4–5-fold higher than intact fruit at day 1. Afterward, the ethylene production of fresh-cut cubes declined significantly whereas that of intact fruit remained relatively constant at about 0.69–1.04 ng kg−1 s−1. 1-MCP delayed mesocarp softening in both fresh-cut and intact fruit and the symptoms of watersoaking in fresh-cut fruit. Continuously stored fresh-cut cubes and cubes derived from intact fruit not treated with the ethylene antagonist softened 27% and 25.6%, respectively, during 10 d storage at 5 °C while cubes derived from 1-MCP-treated fruit softened 9% and 17%, respectively. Fresh-cut tissue from 1-MCP-treated fruit exhibited slightly reduced populations of both total aerobic organisms and Enterobacterium, although the differences did not appear to be sufficient to explain the differences in keeping quality between 1-MCP-treated and control fruit. Based primarily on firmness retention and reduced watersoaking, 1-MCP treatment deferred loss of physical deterioration of fresh-cut ‘Galia’ cubes at 5 °C by 2–3 d compared with controls.

Frequent fertigation of soilless-grown bell pepper (Capsicum annuum L.) can increase fruit production, but development of fruit disorders may offset the increase in yield of first-quality (blemish-free) fruit in greenhouses with minimal environmental control. Fruit yield and quality were studied as affected by water volumes and nutrient concentration levels, delivered with irrigation events initiated after determined cumulative solar radiation levels, in ‘HA3378’ bell pepper from October to May in north–central Florida. Irrigation events occurred after solar radiation integral levels (SRI; ±SD) 1.7 ± 0.42, 3.7 ± 0.42, 5.7 ± 0.42, 7.7 ± 0.42, and 9.7 ± 0.42 kW·min−1·m−2, which led to mean number of daily irrigation events of 61 ± 31, 26 ± 12, 17 ± 8, 12 ± 5, and 10 ± 4 respectively. In peat mix, perlite, and pine bark media, volume per irrigation event and concentration levels of the nutrient solution were, in the first experiment, 74 mL standard (74-s), and in a second concurrent experiment, 74 mL half-standard (74-½s) or 3) 37 mL standard (37-s). In both studies, combined marketable fruit yields of first quality and second quality (minor cracking patterns and yellow spots) increased linearly with decreasing SRI (increased events per day). First-quality fruit weight with 74-s was unaffected by media and, in a quadratic response to SRI, reached 5.4 kg·m−2 at 5.7 kW·min−1·m−2. First-quality weight with 74-½s and 37-s did not differ. Weight was unaffected by SRI in peat mix and perlite, and a quadratic response was recorded in pine bark, with yields of ≤3.6 kg·m−2. Fruit cracking incidence decreased with increased SRI, and was generally greater in pine bark. Incidence of yellow spots doubled with 74-½s compared with 37-s, and decreased linearly with increased SRI; the disorder was minor with 74-s. Compared with 37-s, 74-½s decreased fruit with blossom-end rot by 14%, increased marketable fruit weight by 10% in media with the lowest water-holding capacity (perlite, pine bark), and increased nutrient use efficiency. With any media used, the SRI set point of 5.7 kW·min−1·m−2 (daily mean of 17 irrigation events) and 74 mL, at standard nutrient concentration levels, appeared to produce greater blemish-free fruit yield than delivering 37 mL/event or half-concentrated 74 mL/event within the range of SRI means of 1.7 to 9.7 kW·min−1·m−2 (61–10 irrigation events/day). Disorder-tolerant pepper cultivars, better temperature control, and August plantings are additional suggestions for irrigation management to increase first-quality fruit yield.

'Galia' is a high-quality muskmelon cultivar that is grown in greenhouses or tunnels to maximize fruit quality and yield. 'Galia' has a short shelf life of 2-3 weeks due to rapid fruit softening. In vitro regeneration and transformation of 'Galia' melon parental lines with antisense technology, targeting enzymes involved in the ethylene biosynthesis pathway, is a feasible strategy that can be used to increase its fruit shelf-life. In this study, the male parental line of 'Galia' muskmelon was transformed with two different constructs: one plasmid was bearing the uidA (GUS) reporter gene and another the ACC oxidase gene (CMACO-1) in antisense orientation. Transgenic ACC oxidase antisense (TGM-AS), azygous (PCR negative), transgenic GUS (TGM-GUS) and wild type (WT) fruit, from plants grown in the greenhouse, were harvested at zero-, half-, and full-slip developmental stages. Fruit firmness of full-slip TGM-AS was almost twice that of wild type, azygous and TGM-GUS. Ethylene production and ACC oxidase in half-slip wild type, azygous and TGM-GUS fruit were greater than those from TGM-AS fruit. TGM-AS 'Galia' male parental melon fruit exhibited delayed softening compared to wild type fruit.

Galia-type muskmelon (Cucumis melo cv. Gal-152) was grown as a fall and spring crop to determine the effect of plant density (1.7, 2.5, 3.3, and 4.1 plants/m2) on yield, fruit quality, plant growth, and economic feasibility for producing the crop in a greenhouse. Plant density had no influence on the early or total number of fruit produced per plant. Marketable yields increased linearly from 11.0 to 20.0 kg·m−2 in fall and from 21.9 to 48.3 kg·m−2 in spring with increasing plant density. Mean fruit size was unaffected by plant density during fall (mean weight, 1.0 kg), but was reduced linearly during spring from 1.8 kg at 1.7 plants/m2 to 1.5 kg at 4.1 plants/m2. Soluble solids content was unaffected by plant density in either fall or spring and averaged 10.1% in both seasons. Number of leaves per plant was unaffected by plant density, but internode length was increased at 4.1 plants/m2 compared with plants from the other densities. Increasing the plant density of ‘Gal-152’ muskmelon grown under protected cultivation led to increased yields in both fall and spring without negatively impacting fruit quality. When the market price is $1.44/kg, increased yields at 3.3 plants/m2 can potentially increase net returns over yields of plants spaced at 2.5 plants/m2 by 25% and nearly double net returns from plants grown at 1.7 plants/m2.