The diverse agro climatic zones of the state offer the advantage of growing different fruits. However, Red Delicious gave impetus to commercial apple production in the valley. Apple tree like other plants needs different nutrients in varying quantities to achieve proper growth and fruiting. Besides major elements, macro and micro nutrients are also required in small quantities that assume critical importance when deficient as these are taken up by the plant and need to be replenished. In many cases the quality of harvest produce is determined by the content of the mineral nutrients. In addition, storing stability depends upon the content of distinct mineral nutrients such as calcium and boron. In the present study calcium and boron was applied as pre -harvest spray on Red Delicious apple at fortnightly interval in the month of July. Calcium chloride at 0.1 %, averaged over various concentrations of boric acid resulted in the maximum fruit length (5.89 cm) during both the years. Similarly, boric acid at the lowest concentration 0.05 % indicated high fruit length to the tune of 5.94 cm. The combined application of calcium chloride at 0.1% plus boric acid at 0.15 % recorded the higher fruit diameter (7.16 cm) during first year while as control registered the lowest fruit diameter (5.64 cm). In the second year maximum fruit diameter (7.14 cm) was registered with 0.2% calcium chloride plus 0.15 %boric acid. Kilany and Kilany (1991) also observed significant change in fruit size i.e., length and diameter with the application of calcium chloride and boric acid treatment on apple. The fruits treated with calcium chloride were firm and firmness increased progressively with an increase in calcium chloride concentration from 0.1 to 0.4 per cent. Boric acid at higher level registered maximum firmness in comparison to lower concentration as well as control. Calcium chloride at 0.4 per cent plus boric acid at 0.25 per cent attained maximum firmness when sprayed together. The combined application of calcium chloride and boric acid was found instrumental in increasing TSS as compared either of the nutrient spray application. Both the chemicals used as pre- harvest spray decreased acidity of fruits as compared to unsprayed fruit. Lowest acidity was observed with intermediate level of calcium chloride as well as boric acid during both the years.

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