Calcium is an essential element and an important ubiquitous messenger that participates or modulates many intracellular metabolic processes of plant growth and development ( Bush, 1995 ; Ge et al., 2007a ; Hepler and Wayne, 2005 ; Jones and Lunt
Dongmei Wei, Chao Gao and Deyi Yuan
Nikolaos Koutinas, Thomas Sotiropoulos, Antonios Petridis, Dimitrios Almaliotis, Emmanuil Deligeorgis, Ioannis Therios and Nikolaos Voulgarakis
Calcium (Ca) is an important nutrient associated with fruit quality in kiwifruit. Considerable attention has been given to Ca application to kiwifruit since it was found to prolong storability ( Basiouny and Basiouny, 2000 ). Greater Ca contents
Patricia Newton Myers and Cary A. Mitchell
germplasm for this study. Special thanks is given to undergraduate student James W. Cutler for technical assistance in this study. Thanks also to Terri Kirk and Brian Whipker (Dept. of Horticulture) for assistance with the calcium analysis. Jonathan Frantz
F. Chéour, C. Willemot, J. Arul, Y. Desjardins, J. Makhlouf, P.M. Charest and A. Gosselin
Effects of CaCl2 preharvest treatment on postharvest strawberry (Fragaria × ananassa) ripening and gray mold development were assessed. Two experiments were carried out in 1987 on two sites. In the first experiment, the effects of rate of application of CaCl2 and degree of fruit maturity at treatment were studied with the conventional cultivar Kent. In the second experiment, the influence of concentration and frequency of application of CaCl2 was investigated with day-neutral `Tribute'. Calcium treatment caused a significant increase in fruit and leaf Ca contents, which were closely correlated. The degree of fruit maturity at application and the frequency of treatment did not affect Ca concentration in the tissues. Several maturity criteria were measured during fruit storage in air at 4C. Anthocyanin and free-sugar contents and tissue electrical conductivity increased, while titratable acidity and firmness decreased. In both experiments, Ca treatment delayed ripening and gray mold development. The delay increased with increasing Ca concentration.
W. Dennis Scott, B. Dean McCraw, James E. Motes and Michael W. Smith
Field experiments were conducted to quantify the effect of Ca supplied as gypsum in factorial combination with watermelon [Citrullus launatus (Thumb) Matsum and Nakai] cultivars Charleston Gray, Crimson Sweet, and Tri-X Seedless on yield and the elemental concentration of leaf and rind tissue. Also, the effect that ontogenetic changes and sectional differences had on the elemental concentration in rind tissue was investigated. The experiments were conducted at two locations in Oklahoma. Yield was not affected by Ca; however, mean melon weight was reduced at 1120 kg Ca/ha. Leaf Ca concentration increased linearly in response to Ca rate. `Tri-X Seedless' had lower leaf Ca and higher K concentrations than did `Charleston Gray' or `Crimson Sweet'. Fruit ontogeny (days from anthesis) and melon section (blossom or stem-end) interacted to affect elemental concentrations in the rind tissue. There was also a significant genotypic effect on elemental concentration in rind tissue. Increasing rates of Ca applied to soil reduced the incidence of-blossom-end rot (BER) in `Charleston Gray' melons. Calcium treatment did not affect flesh redness or soluble solids concentration (SSC) of watermelon.
Silver Tumwegamire, Regina Kapinga, Patrick R. Rubaihayo, Don R. LaBonte, Wolfgang J. Grüneberg, Gabriela Burgos, Thomas zum Felde, Rosemary Carpio, Elke Pawelzik and Robert O.M. Mwanga
sweetpotato storage root mineral contents (especially trace minerals) are limited, particularly for African sweetpotato germplasm. Bradbury and Holloway (1988) reported storage root mineral content ranges of ≈75 to 740 ppm calcium, ≈180 to 350 ppm magnesium
Jon R. Johnson
Abbreviation: CaER, calcium efficiency ratio. 1 Assistant Professor. Technical Contribution no. 3132 of the South Carolina Agricultural Experiment Station. The cost of publishing this paper was defrayed in part by the payment of page charges. Under
Yan-xin Duan, Ying Xu, Ran Wang and Chun-hui Ma
, Ca spraying was a useful alleviating measure ( Faust and Shear, 1969 ; Raese and Drake, 1993 , 1995 , 2006 ; Richardson and Lombard, 1979 ). Besides Ca, the levels of other mineral nutrients could also influence fruit susceptibility to calcium
AK. Alva and T.A. Obreza
Deep aquifer water, which contains high levels of bicarbonate and Ca, is used predominantly for citrus irrigation. Changes in soil pH and Mehlich 1 extractable Ca concentrations were examined inside and outside the microsprinkler-wetted zone in 3- to 5-year-old citrus groves on three soils. Soil pH at 0 to 15 cm inside the wetted zone was 0.4, 0.9, and 1.3 pH units higher than that outside the wetted zone in Immokalee, Myakka, and Holopaw sands, respectively. This pH increase was due to the addition of bicarbonate in the irrigation water. Extractable Ca concentrations were also about two-fold higher inside compared to those outside the wetted zone at depths of O to 15 and 15 to 30 cm. With young trees, a majority of the roots are within the microsprinkler-wetted zone; therefore, soil samples should be taken inside the wetted zone for measuring soil pH and status of plant nutrients.
Timothy K. Hartz, Paul R. Johnstone, Richard F. Smith and Michael D. Cahn
presence of even a few affected leaves in a consumer product is unacceptable. Tipburn is generally recognized as a localized calcium (Ca) deficiency that induces collapse and necrosis of the margins of actively expanding leaves ( Collier and Tibbitts, 1982