A NEW STRATEGY TO ENRICH CALCIUM NUTRITION OF FRUIT: SYNERGISTIC EFFECTS OF POSTHARVEST FOLIAR CALCIUM AND BORON SPRAYS

Abstract

The objective of the study is to investigate the role of calcium (Ca) and boron (B) synergy in higher maintenance of Ca in fruit buds during senescence. To study the hypothesis, an experiment was conducted for two years in two ‘Starking Delicious’ apple (Malus domastica Borkh.) orchards established on seedling rootstocks in Banaz, Usak, Turkey. Treatments composed of postharvest foliar sprays of Ca at rate of 15.13 kg h⁻¹, B at rate of 2.47 kg h⁻¹ and their combination (Ca+B) compared with control trees sprayed with water. Fruiting spurs, flower ovaries, young and mature fruits were sampled and analyzed for their Ca, B, potassium (K) and magnesium (Mg) contents. Fruit were stored for six months and quality attributes were studied. Results put forth that Ca+B treatments significantly increase fruit Ca and B concentrations and firmness. The results displayed that postharvest B spray improves Ca nutrition of fruits through synergism of Ca+B on Ca translocation.

Keywords:

• boron
• micronutrients
• calcium
• macronutrients
• nutrient translocation
• postharvest
• fruit crops

ACKNOWLEDGEMENTS

This study was funded by the Turkish Scientific and Technological Research Council (TUBITAK) under grant TOGTAG 2573/7 and Ege University Science and Technology Center (2005 BİL 022). The authors wish to extend their thanks to Dilek ANAC and Ernest KIRKBY for their valuable comments.