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Six mid-season orchard sprays of ethylenediaminetetra-acetic acid (EDTA), oxalic acid, 2,3,5-triiodobenzoic acid (TIBA), and CaCl, did not consistently influence Ca concentration in leaf, fruit peel, or fruit flesh of 6 cultivars of apple (Malus domestica Borkh.).
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Himelrick et al. (1981) studied this question.
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