suitable environmental conditions and then begin flowering ( Labate et al., 2006 ). However, unsuitable temperatures produce malformed curds, such as buttoning curds, riceyness curds, or bolting in the small plant stage. Fernández et al. (1997) indicated
cultivation medium. The recent more common occurrence of unfavorable weather conditions such as large rainfall and temperature fluctuations have resulted in the search for other means to optimize yield and quality of tomatoes. Amongst these is the use of
requires significant energy, so environmental alternatives to reduce ethylene synthesis and sensitivity of plants warrants exploration. Temperature significantly influences ethylene synthesis ( Bours et al. 2013 ; Ciardi et al. 1997 ; Field 1981
It is well known that soil temperature changes have a significant impact on the growth and development of plants both in agricultural and native ecosystems ( Bonan, 1992 ). During plant growth, optimum temperature is required below- and aboveground
cranberry fruit are not clearly defined. In various handbooks published in the past 20 years, recommended storage temperatures range from 2 to 7 °C ( Hardenburg et al., 1986 ; Kader, 1997 ; Kasmire and Thompson, 1992 ; Lidster et al., 1988 ; Prange, 2004
a , 2012 ; Iglesias and Echeverría, 2009 ). Anthocyanin synthesis in the fruit skin of red cultivars is affected by external biotic and abiotic factors, including nutrients, water stress, wounding, light, and temperature ( Ubi, 2004 ). The effect
Abstract
Poinsettias (Euphorbia pulcherrima Willd. cv. Annette Hegg Brilliant Diamond) were grown in separate greenhouses, one in which the night air temperature was maintained at 16.7°C and another where the air temperature was allowed to fall to 11.5°. The cool-air-treated plants were subjected to root-zone temperatures of 17°, 23°, 26°, and 29°. In general, the deleterious effects of cool air temperatures could be reversed by root-zone warming at 23°.
Abstract
Three- to 4-month-old seedlings of an improved selection of Asparagus officinalis L. cv. Mary Washington were artificially hardened and crowns subjected to controlled freezing tests. Two low-temperature acclimation regimes were used. The first was 3C for 0, 1, or 2 weeks before freezing at 0, −5, or − 10C; the second, 3C for 0, 1.5, or 3 weeks, followed by freezing at 0, −2.5, −4.5, −6.5, or −8.5C. Regrowth tests showed that hardiness increased with 2 and 3 weeks of acclimation, with tolerance to −5 and −6.5C, respectively. Water-stressed seedlings (relative water content at 57%) withstood exposure to −5C, but not to −6.5C; rehydrated crowns and well-watered controls were hardy to −3.5C.
The short-term effects of photosynthetic photon flux (PPF), day/night temperatures and CO2 concentration on CO2 exchange were determined for two Phalaenopsis hybrids. At 20 °C, the saturating PPF for photosynthesis was 180 μmol·m-2s-1. At this PPF and ambient CO2 level (380 μL·L-1), a day/night temperature of 20/15 °C resulted in the largest daily CO2 uptake. Higher night temperatures probably increased the respiration rate and lowered daily CO2 uptake in comparison with 20/15 °C. An increase in the CO2 concentration from 380 to 950 μL·L-1 increased daily CO2 uptake by 82%.
The respiration of cut flowers of gerbera (Gerbera jamesonii H. Bolus ex Hook.f. `Vesuvio') and sunflower (Helianthus annuus L.) increased exponentially with increasing storage temperature. Poststorage vase life and negatively gravitropic bending of the neck of the flowers were both strongly affected by simulated transport at higher temperatures. Vase life and stem bending after dry storage showed highly significant linear relationships (negative and positive, respectively) with the rate of respiration during storage. The data indicate the importance of maintaining temperatures close to the freezing point during commercial handling and transport of these important commercial cut-flower crops for maximum vase life.