The effect of increasing temperatures on the duration of postharvest flower development was determined for three specialty crop species: marguerite (Argyranthemum frutescens Webb ex Schultz-Bip.) `Butterfly' and `Sugar Baby'; swan river daisy (Brachycome hybrid Cass.) `Ultra'; and bacopa (Sutera cordata Roth.) `Snowflake'. Plants were grown in a greenhouse at 18 °C (65 °F) until flowering, and then transferred into a phytotron to determine heat tolerance. Plants were stored for 8 weeks at constant temperatures of 18, 23, 28, and 33 °C (65, 73, 82, and 91 °F) for 2-week intervals. Flower bud and flower number were recorded weekly. Sutera cordata `Snowflake' and B. hybrid `Ultra' had the greatest flower number at the 23 °C temperature, decreasing in the 28 °C environment. Argyranthemum frutescens `Butterfly' and `Sugar Baby' had greatest flower number at 28 °C, but flowers were of lower quality thanat 23 °C. Flower development of all cultivars ceased at 33 °C, at the end of 8 weeks at increasing temperatures, but when plants were returned to the 18 °C production greenhouse, flower development resumed. High temperatures (28 °C) reduce the postharvest performance of S. cordata, B. hybrid, and A. frutescens plants grown in hanging baskets; therefore, these species should be marketed as spring-flowering products since summer performance may be unsatisfactory in warm climates.
Southern highbush blueberry, a hybrid of northern highbush (Vaccinium corymbosum) and southern-adapted Vaccinium species, has the potential to meet the need for an early-ripening blueberry in the southern U.S. southern highbush cultivars can ripen up to one month earlier than the earliest rabbiteye (Vaccinium ashei) cultivars currently grown in the southern U.S. However, chilling requirement and cold-hardiness are cultivar-dependent for southern highbush and cultivar testing has been necessary to determine the cultivars best adapted to specific hardiness zones. In a 4-year study at Hope, Ark. (hardiness zone 7b), several southern highbush cultivars were evaluated for productivity, fruit quality and reliability of cropping. Yields were based on 1089 plants/acre (2690 plants/ha) for southern highbush cultivars and 605 plants/acre (1494 plants/ha) for rabbiteye cultivars. `Ozarkblue' and `Legacy' showed the most adaptability at this location, yielding on average 11,013 lb/acre (12,309 kg·ha-1) and 10,328 lb/acre (11,543 kg·ha-1) respectively, compared to 4882 lb/acre (5456 kg·ha-1) for `Premier' (rabbiteye) over 4 years. `Ozarkblue' and `Legacy' also rated well for plant vigor and fruit quality. We would recommend `Ozarkblue' and `Legacy' for commercial planting in southwest Arkansas and believe these cultivars have production potential for other areas of the southern U.S. that have similar hardiness zones and soil type to southwest Arkansas.
most crops but AHS heat zones are not; however, the authors do a good job of providing verbal summer heat tolerance information for a number of crops. A number of short chapters follow. A tiny one, “species best avoided,” lists five genera to avoid. The
tolerance factors needed for a successful cultivar ( Table 7 ), British Columbia growers ranked heat tolerance as the most important and drought resistance as the least important challenge. Oregon growers ranked rain damage tolerance as most important
, and is also competitive against weeds. Hybrid bermudagrass has excellent heat tolerance and recovery properties resulting from the abundance of stolons and rhizomes ( Adamipour et al., 2016 ; McCarty and Miller, 2002 ; Volterrani et al., 1997 ). The
biostimulant on the heat tolerance associated with photosynthetic capacity, membrane thermostability, and polyphenol production of perennial ryegrass Crop Sci. 47 261 267 Krishnan, S. Laskowski, K. Shukla, V. Merewitz, E.B. 2013 Mitigation of drought stress
.M. Khachik, F. 2003 Distribution of lutein, zeaxanthin, and related geometrical isomers in fruit, vegetables, wheat, and pasta products J. Agr. Food Chem. 51 1322 1327 Kauffman, G.L. III Kneival, D.P. Watschke, T.L. 2007 Effects of biostimulant on the heat
Star’ ( Table 3 ). However, ‘Green Bell Improved’, which is noted for heat tolerance, showed like ‘Andalus’ a relative small reduction of around 10% in total yield during the cool-dry compared with hot-wet season ( Table 3 ). ‘Andalus’ and ‘Green Bell
late summer, likely as a result of lack of heat tolerance of the flowers ( Clark, 2008 ; Stanton et al., 2007 ). However, when these same experimental cultivars were grown in Aurora, OR, harvest commenced in August and extended into October ( Strik et
three cultivars are better suited for stand establishment in a semiarid climate than are the remaining cultivars evaluated in this study. Whether this reflects differential heat tolerance of the cultivars or inherent quality traits of cultivars under