Cuticular calcium penetration is directly related to the area covered by calcium within droplet spread area

Improving the performance of calcium-containing spray formulations to limit the incidence of bitter pit in apple (Malus x domestica Borkh.)

“…Similarly, maximal leaf Ca concentrations were recorded after application of both CaCl 2 containing formulations (i.e., with CMC or Tween 20) suggesting the higher permeability of apple fruits and leaves to CaCl 2 as compared to Ca-propionate as a Ca source. Increased Ca penetration rates in association with CaCl 2 versus other Ca-containing compounds such as e.g., Ca-acetate (Kraemer et al, 2009a,b), Ca-EDTA (Manganaris et al, 2005 or Ca-propionate (Schönherr, 2001) have been previously reported, which can be associated with the lower molecular size and lower point of deliquescence of the salt as compared to the organic compounds (Schönherr., 2001;Kraemer et al 2009a). …”

“…Recently, Kraemer et al (2009a) showed that Ca penetration is directly related to the area covered by Ca within the spray droplet, which was found to vary in relation to the addition of a surfactant. Therefore, it could be also the case that CMC may affect the distribution of Ca in the drops after dipping apples into the solution or spraying the treatments under field conditions as suggested by Kraemer et al (2009a,b).…”

Foliar Calcium Applications for Controlling Fruit Disorders and Storage Life in Deciduous Fruit Trees

“…Schönherr 31 showed that adding small amounts of wetting agents increased the rate constants of penetration almost 10 times and explained that wetting agents doubled the area of the salt residue and improved contact between salt solutions and the micro-relief of epicuticular. Adding rapeseed oil as a surfactant to CaCl 2 or calcium acetate (Ca(CH 3 COO) 2 ) enhanced droplet spreading, which meant a greater area covered by Ca within the droplet residues, and increased penetration through isolated cuticular membranes of apple leaves 17 . Adding sodium salt of carboxymethyl ether of cellulose (0.5%, CMC, used as a food additive) as an adjuvant for Ca spray, meanwhile, increased the retention of Ca-containing solutions by the apple skin and prolonged the drying process of the solution at room temperature 4 .…”

Does the microclimate under hail nets influence micromorphological characteristics of apple leaves and cuticles?

“…The cuticular permeability was determined using the finitedose-system by quantifying the amount of penetrated active ingredient after a predefined time (Kraemer et al, 2009a). The foliar fertilizer calcium chloride (CaCl 2 ·2H 2 O, Merck KGaA, Darmstadt, Germany) in a concentration of 10 g CaCl 2 L −1 was used as a model substance for penetration of polar substances through cuticles.…”