Effect of Ca, Zn and B Spray Application on Preharvest Fruit Drop, Sugar and Nutrient Contents and on some Quantitative and Qualitative Fruit Characterestics in some Asian Pear (Pyrus serotina Rehd.) Cultivars

Khoshghalb, Hasan; ARZANI, Kazem; MALAKOUTI, Mohammad Jafar; BAZEGAR, Mohsen

doi:10.22059/ijhs.2013.35048

Effect of Ca, Zn and B Spray Application on Preharvest Fruit Drop, Sugar and Nutrient Contents and on some Quantitative and Qualitative Fruit Characterestics in some Asian Pear (Pyrus serotina Rehd.) Cultivars

Document Type : Full Paper

Authors

Hasan Khoshghalb ¹

Kazem ARZANI ²

Mohammad Jafar MALAKOUTI ²

Mohsen BAZEGAR ³

¹ Assistant Professor, Shahrood University of Technology, Shahrood, Iran.

² Professor University of Tarbiat Modarres

³ Associate Professor, University of Tarbiat Modarres

10.22059/ijhs.2013.35048

Abstract

The effect of Ca, Zn and B spray application on preharvest fruit drop, sugars, calcium, zinc, and boron concentrations and as well on some physicochemical fruit properties of five commercial Asian pear cultivars (‘KS’₇, ‘KS’₈, ‘KS’₁₁, ‘KS’₁₂ and ‘KS’₁₄) was investigated under Tehran Province^,s environmental conditions. Trees were sprayed one month past fruit set until harvest within two week intervals with Ca, Zn, B and as well with their mixtures at 5% concentrations. Fruit drops were recorded from treatments^, start untill harvest. At the time of fruit harvest, fruit sugar and mineral contents were determined using HPLC and ICP, respectively. Results revealed that Ca, Zn and B applications decreased preharvest fruit drop in a way that a combination of Ca, Zn, and B applications rendered a 6.3% fruit drop in comparison with 17.3% occurring in control. Throughout the research, fructose was found out as the dominant sugar followed by glucose, sorbitol and sucrose in the studied cultivars. Spray applications of Ca, Zn and B increased the fruits^, fructose, glucose, sorbitol and sucrose contents in all the studied cultivars (1-2.5, 1-2.1, 2-3.7 and 0.7-2.2 % fresh weight, respectively). In addition, total soluble solids increased by 1-2 ºBrix total sugars (1-2 % of fresh weight), total acidity (0.07-0.12 mg 100^-1g) and dry weight (1-1.5g) of fruits in all cultivars. Spray of Ca increased fruit firmness (1-2 N varied with cultivar). Spray of Ca, Zn and B applications increased Ca, Zn and B mineral contents of both leaves and fruit.

Keywords

Acidity

Asian pear

firmness

Physicochemical properties

Sugar