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Juan Carlos Díaz-Pérez and James E. Hook

Bell pepper (Capsicum annuum L.) plants have a high demand for water and nutrients. Water stress on bell pepper is associated with reduced yields and incidence of blossom-end rot (BER). High irrigation rates are commonly applied to maximize yields. Excessive irrigation rates, however, may negatively affect bell pepper plants. The objective of this study was to evaluate the effects of irrigation rates and calcium fertilization on plant growth and fruit yield and quality. Trials were conducted in the spring of 2001, 2003, and 2005 at the University of Georgia, Tifton Campus. Drip-irrigated bell pepper (‘Camelot’ or ‘Stiletto’) plants were grown on black plastic mulch. Plants were irrigated with rates that ranged from 33% to 167% of the rate of crop evapotranspiration (ETc). Results showed that irrigation at 70% ETc (2001), 67% ETc (2003), and 50% ETc (2003) were sufficient to maximize vegetative growth and fruit yield and provided yields similar to those at 100% ETc. Leaf net photosynthesis and stomatal conductance (g S) were reduced, and incidence of BER was increased with reduced irrigation rates (33% and 67% ETc). Incidences of soilborne diseases (Pythium spp. and Phytophtora capsici) tended to increase in plants receiving excessive irrigation rates (167% ETc). Irrigation rate also affected fruit quality; incidence of BER and fruit soluble solids were both increased at 33% ETc. Calcium fertilization had no effect on soil water content (SWC), plant growth, and incidence of soilborne diseases, and an inconsistent effect on fruit yield and incidence of BER. In conclusion, there is potential for use of irrigation at rates below 100% ETc. Reduced irrigation diminished the volumes of water applied and provided fruit yields similar to those at 100% ETc. Excessive irrigation rates (167% ETc or above) wasted water and resulted in both higher incidences of soilborne diseases and reduced bell pepper yields.

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M.M. Peet and D.H. Willits

Excess irrigation water was provided to spring crops of bag-grown greenhouse tomatoes (Lycopersicon esculentum Mill.) to test the effect on radial fruit cracking. Varied numbers of emitters were placed in bags filled with soilless medium to provide different amounts of irrigation water. In 1990, all emitters provided water containing nutrient solution, but in 1992, the extra water added in one treatment did not contain nutrient solution. In both years, the percentage of cracked fruit was 20 percentage points higher in the treatments receiving more water. The increase in cracking was similar whether or not nutrient solution was added to the extra water. There also were some effects of the extra water on yield. Fruit count per plant was slightly higher (9.5%) when extra water was provided without nutrient solution, but was the same when nutrient solution was added to the extra water. Fruit weights per plant were 18.6% higher in 1990 when watering was increased. In 1992, fruit weights were similar, except for the treatment where the extra water provided did not contain nutrient solution. Fruit weight in this treatment was 19.7% higher than in the other treatments. In both crops, the percentage of cracking increased as linear and quadratic functions of cluster positions, i.e., there was more cracking in the upper clusters. In greenhouse situations, growers should consider water reduction when experiencing high levels of fruit cracking and as a precautionary measure when harvesting from the upper clusters. Providing excess water to greenhouse-grown tomatoes may be a viable technique for screening cultivars or for conducting research on practices to reduce cracking.

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James C. Fulton, Francisco O. Holguin, Robert L. Steiner, and Mark E. Uchanski

Stip is regarded as a physiological disorder of pepper ( Capsicum annuum ) in which symptoms appear as brown, black, and yellow ovoid-shaped chlorotic and/or necrotic pod lesions ≈0.5 to 1.2 cm long and 0.5 cm wide ( Fulton and Uchanski, 2017

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Kristen Young and Eileen A. Kabelka

Squash silverleaf (SSL) disorder is an economically important physiological disorder affecting squash ( Cucurbita pepo L.) throughout the United States, the Caribbean region, and Israel ( Cardoza et al., 1999 ). It is characterized by silvering

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Nicholas D. Warren, Rebecca G. Sideman, and Richard G. Smith

percentage of unmarketable fruit and the total number of fruit are clearly relevant to growers. Other traits, including susceptibility to disease and physiological disorders, are also important and should be included in the overall assessment of cultivar

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Carolina Contreras, Mauricio González-Agüero, and Bruno G. Defilippi

shipping purposes, pepinos are harvested at an early ripening stage, because they are highly sensitive to bruising ( Huyskens-Keil et al., 2006 ). Postharvest Handling and Physiological Disorders One of the first reports on pepino storage potential was

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Corina Serban, Lee Kalcsits, Jennifer DeEll, and James P. Mattheis

physiological disorder that is associated with fruit calcium content ( Miqueloto et al., 2014 ; Rosenberger et al., 2004 ). Economic losses resulting from bitter pit can be considerable, and incidence is often unpredictable annually, between orchards in the

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M.E. El-Mahrouk, A.R. El-Shereif, Y.H. Dewir, Y.M. Hafez, Kh. A. Abdelaal, S. El-Hendawy, H. Migdadi, and R.S. Al-Obeed

high-quality and pathogen-free planting materials and reducing production costs. Hyperhydricity has been described as a physiological disorder of tissue-cultured plants whereby the hyperhydric propagules become translucent due to excessive hydration of

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James P. Mattheis

quality maintenance and avoidance of physiological disorders. Commercialization of 1-MCP as SmartFresh by AgroFresh has provided another tool for postharvest management of apple fruit. This technology has been widely adopted in a relatively short period of

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F. Ghahramani, K.J. Scott, and R. Holmes

`Delicious' (Malus ×domestica Borkh.) apples were kept in sealed polyethylene bags (thickness 0.05 mm) and exposed to ethanol, propan-1-ol, butan-1-ol, and pentan-1-ol during storage at 0 °C. Rates of application varied from 1.85 to 120 mmol·kg-1. Complete control of superficial scald was achieved using 30 mmol·kg-1 of fruit with butan-1-ol or propan-1-ol; ethanol required 120 mmol·kg-1 to control the disorder, but at this concentration, purpling of the red skin occurred. Butan-1-ol and propan-1-ol did not affect the color. Pentan-1-ol caused severe skin injury resembling soft or deep scald of `Jonathan' apples. Apples were also kept in high purity N at 20 °C for up to 8 days before storage at 0 °C. Complete control of scald occurred with a 6- or 8-day exposure to N. Control of scald appears to be due to the accumulation of ethanol during exposure to N. Nitrogen treatments did not affect skin color.