stress. Both salicylic acid (SA) and calcium chloride (CaCl 2 ) are signal molecules known for their roles in plant adaptation to changing environments. They influence various stress responses and regulate the physiological and biochemical mechanisms in
Kuan-Hung Lin, Shao-Bo Huang, Chun-Wei Wu and Yu-Sen Chang
G. Lysiak, W.J. Florkowski and S.E. Prussia
fruit firmness was among the most important characteristics consumers used to judge eating quality. In this study, a postharvest application of calcium chloride (CaCl 2 ) was evaluated as a method for improving peach firmness. CaCl 2 is a naturally
Eleni Tsantili, Miltiadis V. Christopoulos, Constantinos A. Pontikis, Pantousis Kaltsikes, Chariklia Kallianou and Michalis Komaitis
with Ca solutions ( Ferguson and Watkins, 1989 ). Preharvest calcium chloride (CaCl 2 ) treatments resulted in increased firmness in some fruit crops, like in apples ( Recasens et al., 2004 ), cherries ( Facteau et al., 1987 ), and peaches ( Manganaris
Uttara C. Samarakoon, James E. Faust and John M. Dole
D ) as a percentage of leaf dry matter (DM) measured on poinsettia and geranium leaves after weekly foliar applications of Ca in the form of calcium chloride applied to stock plants during cutting development (Expts. 1 and 2). Vertical bars represent
Timothy W. Coolong and William M. Randle
for the main effects of ammonium sulfate [(NH 4 ) 2 SO 4 ] and calcium chloride (CaCl 2 ) applications for cured yield of cv Georgia Boy onion in 2005 and 2006. No treatment interactions were observed. To confirm the efficacy of the fertility
Alan R. Biggs and Gregory M. Peck
-Cal™ 24 May, 7 June, 21 June, 5 July, 19 July, and 2 Aug. Antitranspirant was added on 7 June, 5 July, and 2 Aug. Calcium chloride treatment rates were selected to match standard grower practices in Virginia, whereas the manufacturers recommended the
Eric J. Hanson, Jane L. Beggs and Randolph M. Beaudry
Immature and marketable highbush blueberries often are separated by buoyancy in water tanks. Calcium chloride was added to the water to improve berry firmness or integrity. Berries were immersed in 0% to 4% CaCl2 and held at 2C for several days. Vertical compression of a column of berries decreased linearly with increased CaCl2 concentration, a result indicating that CaCl2 increased the ability of the berries to resist physical damage. Immersion duration (0.5, 2, or 4 minutes) did not affect results. However, rinsing berries in water immediately after immersing them in CaCl2 negated the effect. Taste panelists associated an objectionable, salty taste with berries immersed in 2% and 4% CaCl2, but not for those immersed in 1% CaCl2.
Xiaogang Li, Ling Jin, Jing Ling and Zhongchun Jiang
Foliar application of hormones and nutrients can improve fruit quality, but specific conditions for applying hormones and nutrients may vary among fruit species. The objective of this study was to determine the effects of 6-BA, potassium phosphate (monobasic), and calcium chloride on fruit weight, palatability, and storage quality of 8-year-old pear trees, cv. Hosui. Foliar applications of 1 mg·L-1 6-BA, 0.3% potassium phosphate, 0.3% calcium chloride, or 0.3% potassium phosphate + 0.3% calcium chloride were made at 20-day intervals from June until maturity. All foliar applications increased average fruit weight over the control (distilled water). 6-BA or the combination of potassium phosphate and calcium chloride increased fruit weight more than did potassium phosphate or calcium chloride alone. Fruit palatability, measured as the ratio of sugar content to acid content, was significantly lower in 6-BA, potassium phosphate, and calcium chloride treatments than in the control. All treatments increased vitamin C content over the control. Fruit storage quality in calcium chloride or calcium chloride + potassium phosphate treatments was superior to that in the control. Potassium phosphate alone and 6-BA treatments had no effects on fruit storage quality. We conclude that foliar applications of 0.3% potassium phosphate + 0.3% calcium chloride or 1 mg·L-1 6-BA can increase average fruit weight and improve fruit palatability.
Matt Reed, Brie Genter and J.A. Flore
We have developed a system of automated intermittent salt application above the tree during a rain event that has shown very encouraging results (Washington State Hort Soc. Proc. 1995, Good Fruit Grower, vol. 47; pp. 23-24; Acta Hort. vol. 468 pp. 649 & 683) in Michigan and the Pacific Northwest. In 1998, we significantly reduced rain cracking with the system used in previous years. At the Southwest Michigan Research and Extension Center (SWMREC), on `Ulster', the control averaged 18% while the 0.5% calcium chloride had 6.7% cracks. Similar results were found for `Ulster', `Somerset', and `Rainer' at the Northwest Station. Cracking was greater in the upper part of the tree than the lower part for the control. The calcium chloride had less cracking on the upper part than the lower part indicating that calcium chloride applied from above the tree was not uniformly distributed to the lower part of the canopy in high enough concentrations. Multiple emitters per tree decreased this problem. We determined that there was an interaction with temperature. More fruit cracked at high temperature than low temperature. In the field more fruit cracked during the day than at night. We attribute this to the difference in day and night temperature. Using a bioassay system we able to determine the critical concentration of salt that must be on the fruit to inhibit water uptake and rain splitting up to a 4-h period. It ranged between 0.05% to 0.10 % depending on the variety and stage of development.
Mark A. Ritenour*, Peter J. Stoffella, Zhenli He and Michael S. Burton
Previous research suggests that treatment of sliced or vacuum-infiltrated tomato fruit with calcium chloride (CaCl2) solutions may reduce decay, but no work on dipping whole tomatoes has been reported. In the present experiments, `FL 47' tomato fruit were collected at the mature green or pink stage from a local packinghouse, held at 12.5 or 25.0 °C overnight, and then dipped in solutions with 0.5% to 5% CaCl2 with or without 150 ppm sodium hypochlorite. Fruit were dipped for 1 to 4 minutes at temperatures ranging from 0 to 35 °C. Mature green fruit dipped in solutions with 0.5% and 1.0% CaCl2 at 35 °C had significantly lower rates of decay following storage at 12.5 °C (90% RH) than the control (27% vs. 36% decay, respectively). These fruit were also significantly softer after 2 weeks of storage than control fruit (0.85 mm vs. 0.74 mm deformation, respectively) and appeared to be slightly more ripe. Decay in fruit dipped in 2% CaCl2 was not significantly different from the control, while fruit dipped in 3% to 5% CaCl2 developed significantly more decay than control fruit. The CaCl2 treatments had no significant effect on decay of fruit treated at the pink stage and none of the treatments at 0 °C significantly affected postharvest decay. Dips in 2% to 5% CaCl2 significantly increased tomato peel calcium content after storage. Dipping time had no significant effect on peel calcium content.