Heterosis studies on single, triple and double crosses hybrids in melon (Cucumis melo var. cantalupensis) breeding

Quantitative work of the research was conducted during 2007-2008 spring cultivation season in open field conditions. Also, molecular part of the study was conducted during the 2008-2009 years in molecular biology laboratory. In order to determine the quantitative characteristics of 53 hybrid melon genotypes which are obtained by double, triple and quadruple hybridization, and to molecularly compare the parent material of melons of single, triple and double hybrids, and pure lines used as parental material and Galia F1 hybrid were used as control group.In this research, emergence was monitored and lengths of the cotyledons and hypocotyl were measured following the seed sowing. Besides, the appearance of first true leaves, plant height, main stem diameter, node number, first opening of female flower which is important in early bearing, total and early yields, fruit weight, fruit diameter, fruit height, fruit flesh thickness, fruit skin thickness, seed cavity diameter, seed cavity height, fruit flesh efficiency, total soluble solids (TSS) were determined. Also heterosis and heterobeltiosis rates were calculated.According to the results, the highest heterobeltiosis (184.23 %) and heterosis (184.55 %) rates was produced by OK-58 (G22 X C1) genotypes belonged to the single hybrid group in early yield. At the same time, superiority of single hybrid group was observed in both in total and early yield. Single cross increased the earliness due to early flowering and this cross was showed better performance for fruit weight, diameter and seed cavity.In molecular studies, 55 Simple Sequence Repeat (SSR) markers were screened and after screening Polymorphic SSR primer with the primer single, triple and double as a molecular hybridization of the parents were compared. SSR primers used in the screening of 55 primers, eight of the 55 SSR primers were found polymorphic. Smilarity rate was found between 0.54-1.00 in the dendogram which is obtained by the results of SSR analysis.