Effect of Foliar Spray with IAA and GA3 on Production and Protein Synthesis of Two Summer Squash Hybrid Cultivars

A field experiment was carried out during 2015 and 2016 summer seasons at the Experimental Farm of the Vegetable Department and the Molecular Laboratory of Genetics Department, Faculty of Agriculture, Assiut University, Assiut, Egypt to study the effect of foliar spray by indoleacetic acid (IAA) and gibberellic acid (GA3) on the production and protein synthesis of two F1 summer squash hybrids (Rosina F1 and Eskandrani F1). The indoleacetic acid concentrations were 0,2.5,5 or 10 ppm and the gibberellicacid concentrations were 0,2.5,5 or 10 ppm. The results showed that IAA and GA3 had a significant influence on the most studied traits in favor of 2.5 ppm IAA and 2.5 ppm GA3. Furthermore, the obtained data indicated superiority of Rosina F1 hybrid over Eskandani F1 hybrid for all studied traits except sex ratio. Moreover, the different second order interactions had an inconsistent significant effect on the most studied traits. Rosina F1 summer squash plants which were sprayed with 10 ppm IAA without GA3 gave the highest mean values for total fruit yield/feddan. Spraying squash plants with GA3 induced the synthesis of 8 new protein bands, while 10 new proteins were induced by IAA. The two F1 hybrids of squash exhibited different protein patterns in response to thetreatments combinations of GA3 and IAA. Eskandrani F1 was highly sensitive to GA3 and IAA treatments than Rosina F1 which showed a reduction of several protein bands and low number of induced proteins.