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Thomas L. Davenport, Thomas L. White, and Stanley P. Burg

U.S. regulations prevent importation of fresh horticultural commodities that have not received an approved quarantine treatment assuring 99.999% (Probit 9) mortality of potentially invasive insect pests. Because imported mangoes (Mangifera indica) are likely to be infested by the caribbean fruit fly (Anastrepha suspensa) and other tropical fruit flies in the Americas, such as the mexican fruit fly (A. ludens), guava fruit fly (A. striata), inga fruit fly (A. distincta), south american fruit fly (A. fraterculus), sapote fruit fly (A. serpentina), and the west indian fruit fly (A. obliqua), they must be hot-water treated prior to shipment in order to satisfy quarantine requirement. Hot water treatment often damages the fruit, especially if it is not fully mature. Hypobaric [low pressure (LP)] intermodal shipping containers developed by the VacuFresh Corp. preserve fresh commodities, such as horticulturally mature mangoes, far longer than is possible using other technologies. We tested the ability of caribbean fruit fly eggs and larvae to survive simulated optimal hypobaric conditions for shipment of mangoes [15 and 20 mm mercury (Hg), ≥98% relative humidity, 13 °C (the lowest, safe nonchilling temperature)]. Caribbean fruit fly eggs or larvae were maintained on agar media, flushed with one air change per hour at the storage pressure, and shielded with Mylar to prevent radiant heat uptake and limit evaporative cooling. Nearly 98% of the eggs and larvae were killed within 1 week at 15 and 20 mm Hg in nine replicated experiments. All eggs were killed by 11 days with a predicted kill of 99.999% of the eggs by 9.4 days in 15 mm Hg and 10.6 days in 20 mm Hg LP (based on Probit 9 statistical analysis), whereas a substantial number of eggs survived to 14 days at atmospheric pressure (760 mm Hg). Shipment of fresh produce using this technology promises to provide quarantine control while preserving the freshness of fully mature tropical fruits and vegetables.

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Thayne Montague, Roger Kjelgren, and Larry Rupp

Growth of woody landscape plants is strongly affected by the underlying surface. In urban areas, plants are subjected to energy balance characteristics of a variety of surfaces. This research investigated energy balance properties of six common urban surfaces: Kentucky bluegrass, pine bark mulch, concrete, asphalt, lava rock mulch, and gravel rock mulch. Each summer over a 2-year period incoming global radiation (GW), relative humidity, and air temperature were measured over each surface, and surface reflectivity (AW), surface temperature (TS), soil temperature (TO), and soil heat flux (SF) were measured below each surface. Thermal conductivity (K) and emitted surface longwave radiation (LW) were also calculated. Surface property differences were determined by regression analysis. Incoming global radiation (independent variable) versus TS, TO, SF, LW data (dependent variable) were analyzed. Linear or quadratic curves were selected according to significance of each variable and the coefficient of determination (R2). Surface reflectivity was greatest for concrete and least for lava rock mulch, and K was greatest for asphalt and concrete and least for lava rock and pine bark mulch. Under maximum GW, regression data indicate that SF and TO would be greatest under asphalt and least under lava rock and pine bark mulch. Under similar circumstances, TS and LW would be greatest for pine bark mulch and least for Kentucky bluegrass. This research revealed that more energy was conducted into the soil below asphalt and concrete, and that a greater portion of GW was prevented from entering the soil below pine bark and lava rock mulch than below other surfaces. Due to these effects, and the lack of evaporative cooling, surface temperatures were greater, and more longwave radiation was emitted from, non-vegetative surfaces than from turf.

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Shigeoki Moritani, Hirotada Nanjo, Atsushi Itou, and Teruki Imai

occurrence of the adiabatic evaporation, the air temperature cannot be allowed to decrease below the wet bulb temperature ( Alkhedhair et al., 2016 ). Consequently, evaporative cooling systems are incapable of significantly decreasing high temperatures that

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Bau-Show Lin and Yann-Jou Lin

“tree” ( Table 4 ). LAI has been reported to affect the cooling properties of plants ( Kumar and Kaushik, 2005 ; Takakura et al., 2000 ; Tanaka and Hashimoto, 2006 ). Larger LAI also had greater evaporation ( Rey, 1999 ) as well as greater

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Susmitha Nambuthiri, Robert L. Geneve, Youping Sun, Xueni Wang, R. Thomas Fernandez, Genhua Niu, Guihong Bi, and Amy Fulcher

evaporative cooling from the porous sidewall material ( Table 2 ). Evaporative cooling also appears to be a factor in reducing substrate heat buildup in WP containers relative to both Plastic and KR containers, which are nonporous ( Table 2 ; Figs. 1 and 2

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Allen V. Barker

. Evaders are animals that avoid the heat, and endurers tolerate the heat. Evaporators are a third class of animals that cool by evaporation of water from their bodies. Size of the animals is important in the strategy employed, with small animals generally

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Brian Makeredza, Michael Schmeisser, Elmi Lötze, and Willem J. Steyn

evaporative cooling in the tree ( Van de Ende, 1999 ). However, little research has been conducted to relate plant water status to sunburn incidence and severity; the link between plant water status and sunburn seems to be based primarily on observations. In a

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Malik G. Al-Ajlouni, Dawn M. VanLeeuwen, and Rolston St. Hilaire

loss from an actively growing field of uniform surface of cool season grass that is ≈12 cm tall and not short of water ( Allen et al., 2005 ) and a crop coefficient ( K c ) are used to calculate plant water budgets. Each crop has a specific coefficient

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Lee F. Johnson, Michael Cahn, Frank Martin, Forrest Melton, Sharon Benzen, Barry Farrara, and Kirk Post

.C. Cooperative Extension ( Cahn et al., 2013 , 2014 ). CM combines crop coefficients and evaporation coefficients with CIMIS ETo to develop irrigation schedules meeting daily crop water requirements of lettuce, broccoli, and other cool-season vegetables. As well

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Peter Juroszek and Hsing-Hua Tsai

(DAT)] and during the cool-dry season from 27 Nov. 2007 to 7 Apr. 2008 (132 DAT). Table 1 shows information on the prevailing air temperature, precipitation, and evaporation. In the first week of Oct. 2007, a typhoon contributed to the unusually high