Improving productivity, quality and antioxidant capacity of Le-Conte pear fruits using foliar tryptophan, arginine and salicylic applications

Document Type : Original Article


Department of Pomology, Faculty of Agriculture, Cairo University, Egypt


n respect to enhancing productivity and fruit quality of Le-Conte pear, a field study was carried out during two successive seasons (2015 and 2016). The solutions of amino acids treatments including arginine (100 and 200 ppm) and tryptophan (50 and 100 ppm), in addition to salicylic acid (100 and 200 ppm) and control (water only) were sprayed on mature trees untill run off twice, first at full bloom stage and second at initial fruit set stage (after 21 days of full bloom phase). The productivity and different fruit quality parameters were assessed, as well as, measurements of total phenols, total amino acids and antioxidant capacity during fruit development stages. Applying tryptophan, arginine and salicylic acid treatments attained a valuable effect on productivity and fruit quality of pear cv. Le-Conte. Moreover, tryptophan at 100 ppm showed the highest fruit set percentage, yield, fruit weight, L/D ratio, specific gravity, lightness of flesh colour, fruit peel colour, TSS and improved total sugars, total phenols and total amino acids content of pear fruits cv. Le-Conte, whereas salicylic acid at 200 ppm showed the lowest significant fruit abscission percentages, and maintained the highest significant values of antioxidant capacity, ascorbic acid and firmness of Le-Conte pear fruits.