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The environmental and physiological causes of cracking or splitting of soft fruits and citrus as they ripen are not well understood. This paper explores factors contributing to radial cracking in tomatoes, gives suggestions for prevention of cracking, and suggests directions for future research. Fruit cracking occurs when there is a rapid net influx of water and solutes into the fruit at the same time that ripening or other factors reduce the strength and elasticity of the tomato skin. In the field, high soil moisture tensions suddenly lowered by irrigation or rains are the most frequent cause of fruit cracking. Low soil moisture tensions reduce the tensile strength of the skin and increase root pressure. In addition, during rain or overhead irrigation, water penetrates into the fruit through minute cracks or through the corky tissue around the stem scar. Increases in fruit temperature raise gas and hydrostatic pressures of the pulp on the skin, resulting in immediate cracking in ripe fruit or delayed cracking in green fruit. The delayed cracking occurs later in the ripening process when minute cracks expand to become visible. High light intensity may have a role in increasing cracking apart from its association with high temperatures. Under high light conditions, fruit soluble solids and fruit growth rates are higher. Both of these factors are sometimes associated with increased cracking. Anatomical characteristics of crack-susceptible cultivars are: 1) large fruit size, 2) low skin tensile strength and/or low skin extensibility at the turning to the pink stage of ripeness, 3) thin skin, 4) thin pericarp, 5) shallow cutin penetration, 6) few fruits per plant, and 7) fruit not shaded by foliage. Following cultural practices that result in uniform and relatively slow fruit growth offers some protection against fruit cracking. These practices include maintenance of constant soil moisture and good Ca nutrition, along with keeping irrigation on the low side. Cultural practices that reduce diurnal fruit temperature changes also may reduce cracking. In the field, these practices include maintaining vegetative cover. Greenhouse growers should maintain minimal day/night temperature differences and increase temperatures gradually from nighttime to daytime levels. For both field and greenhouse tomato growers, harvesting before the pink stage of ripeness and selection of crack-resistant cultivars probably offers the best protection against cracking. Areas for future research include developing environmental models to predict cracking and exploring the use of Ca and gibberellic acid (GA) sprays to prevent cracking.

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pests and diseases is an integral component of successful landscape IPM. Increased use of pest- and disease-resistant ornamental plants would offer advantages to grounds maintenance professionals by reducing the time needed to monitor key plants in

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Creeping bentgrass ( Agrostis stolonifera L.) is one of the most important turfgrass species for putting greens because of its excellent tolerance to low mowing height (commonly, 5–8 mm) ( Fagerness and Yelverton, 2001 ; Turgeon, 1991 ). As an

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Abstract

Effects of soil pH, tillage practices, P application, and the addition of clay at the planting site on tree size, fruit yield, fruit size, and tree longevity of peaches [Prunus persica (L.) Batsch] for 20 growing seasons are reported. Because of widespread tree death, ‘Loring’ trees were removed after 9 years and the orchard replanted to ‘Winblo’. Soil pH below 5.6 resulted in poor tree growth, low fruit yield, and small fruit size compared to trees grown in soils at higher pH. In the final 10 years of the experiment, marked improvement in tree size, fruit yield, fruit size, and longevity were evident as soil pH increased. The effect of 3 tillage practices—normal plow to a depth of 20 cm, normal plow to a depth of 20 cm plus a 75-cm-diameter ⨯ 122-cm-deep hole at the planting site, and deep plowing to a depth of 58 cm—varied with cultivar. Both methods of soil profile modification (which penetrated the A2 horizon) resulted in increased yield and tree size compared to normal plowing to 20 cm with ‘Loring’ during the first 9 years. During the final 10 years, fruit yield was lower and tree death greater in the deep-plow plots, but there were no differences in fruit yield, tree size, or tree longevity between the other tillage treatments. Phosphorus rates (0, 15, and 30 kg/ha annually) or clay additions did not influence tree size, fruit yield, or tree survival. Results of this study lend strong support for the maintenance of soil pH above 5.6 and good evidence that increase in tree growth, fruit yield, and tree longevity is further enhanced when soil pH is maintained above 6.0.

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Geogenanthus undatus is a newly introduced cultivar of the species G. undatus C. Koch & Linden (seersucker plant), native to Peru ( Graf, 1963 ). The species has a low-growing habit with fleshy, broad, ovate metallic green leaves with

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temperatures are not a major issue for poinsettias in the retail environment because the optimum temperature for them is similar to that needed to keep people comfortable, but low temperatures can negatively impact plants, so it is recommended that plants be

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plant water status. Ls of CO 2 uptake was mitigated efficiently by VPD regulation in the current study. As mentioned, sustained stomatal function for CO 2 uptake in the low-VPD treatment can be attributed to the maintenance of water balance and

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compounded when foraging skunks, raccoons, or crows turn over infested turf. It has been reported that 10 to15 grubs per 0.1 m 2 in a high-maintenance turf, or 4 to 5 grubs per 0.1 m 2 in a low maintenance turf are sufficient to cause noticeable damage

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photoassimilates are used for new growth and maintenance of existing tissues and organs. Because PPF is the driving force behind photosynthesis, generally more photoassimilates are produced as the PPF level increases. Indoor environments typically have low PPF

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Development of high-density production systems on dwarfing rootstocks for sweet cherry is currently an area of active research ( Lang, 2009 ; Robinson et al., 2008 ). These systems are advocated as inherently more profitable than low

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