Orchard Cooling with Pulsed Overtree Irrigation to Prevent Solar Injury and Improve Fruit Quality of `Jonagold' Apples

Abstract

<jats:p>Pulsed application of overtree irrigation for evaporative cooling of `Jonagold' apples (<jats:italic>Malus domestica</jats:italic> Borkh.) reduced visible solar injury by 15.8% (1991) and 9.4% (1992). Maximum fruit surface temperature was reduced by 8.1 °C on a day when the average surface mean of nonsprayed fruit rose to 45.6 °C. Air heated more slowly than the exposed fruit surface and was cooled only 1 to 2 °C by overtree irrigation. Cooling did not affect fruit size, firmness, or redness but reduced soluble solids concentration and increased titratable acidity. Storage breakdown was unaffected in the first year but was reduced by 6.0% in the second year.</jats:p>

Influence of environmental factors on conidial germination and survival of Sphaeropsis pyriputrescens

“…The ability of conidia to germinate at high RH without continuous wetness suggests that orchard practices that lead to high RH in the orchards may create conducive conditions for infections of apple fruit by this fungus. In commercial apple orchards in central Washington State, over-tree evaporative cooling of fruit in summer is a common practice for protecting fruit from sunburn, a non-infectious disorder on the peel of apple fruit caused by high temperature and long exposure to solar radiation (Flore and Dennis 1990;Parchomchuk and Meheriuk 1996). Over-tree cooling may run for several hours, creating a long wetness period on the fruit and a high RH microenvironment in the orchard.…”

Preharvest effects on postharvest quality of spring-planted, day-neutral strawberries in high tunnels

“…Application of evaporative cooling (i.e. hydrocooling) pre-harvest is potentially impactful for pest and disease control (Dara, 2012), fruit maturity, fruit storage characteristics, fruit color development (Parchomchuk and Meheriuk, 1996;Van Den Dool, 2006;Lantz et al, 2010a;Koike et al, 2009). Typically used amongst produce growers are evaporative cooling systems with aboveplant misters or sprinklers.…”

“…Typically used amongst produce growers are evaporative cooling systems with aboveplant misters or sprinklers. Depending on the produce species and genotype, evaporative cooling has shown to enhance yield weights, redness color, and storage life quality in grapes and apple production (Parchomchuk and Meheriuk, 1996;Evans, 2004;Aljibury et al, 1975). Parchomchuk and Meheriuk (1996) found the use of evaporative cooling for 'Jonagold' apples reduced soluble solid concentration and increased titratable acidity and storage times but did not affect fruit size, firmness, or redness.…”

“…However, Dara (2016) found a reduction of salt injury, mite infestation, and Botrytis cinerea with no indication of yield or internal temperature changes with the use of the micro-sprinklers. Typically used amongst produce growers in orchard production and some commercial berry applications are evaporative cooling systems with above-plant misters or sprinklers (Parchomchuk and Meheriuk, 1996;Evans, 2004). In California, vineyards have adopted the strategy of overhead sprinklers with temperatures over 90°F to cool the fruit temperature.…”

Particle films and their applications in horticultural crops

“…Evaporative cooling entails the wetting of fruit with overhead sprinkles in order to decrease peel temperature (Unrath and Sneed, 1974;Parchomchuk and Meheriuk, 1996). Particle films consisting of white clay minerals, e.g., 'Surround', or natural lipids, e.g., 'Raynox', reflect visible or UV radiation are successful in reducing peel temperatures and solar injury significantly Schupp et al, 2002Schupp et al, , 2004, and are more affordable than evaporative cooling, and effective in reducing the occurrence of solar injury in several fruits and vegetables (Sibbett et al, 1991., Gindaba andWand, 2005;Glenn et al, 2002;Schupp et al, 2002;Le Grange et al, 2004;Melgarejo et al, 2004;Wand, 2008., Schupp et al, 2004;Wunsche et al, 2004 (Table 3).…”