Field experiments were conducted during summer seasons of 2018 and 2019 at Soil Salinity Dept., Soil, Water, and Environment Research Institute, Agriculture Research Center, Alexandria Governorate, Egypt, , to investigate the response of five different genotypes of growing melon to three levels of saline irrigation water (500, 2000, 4000 mg/L). The included genotypes were Line Mass Matrouh, local genotype (G1), Line 22 (G2), Line 26 (G3), Line Ideal (G4) and Line New Matrouh (G5). Results indicated that traits of plant length and number of branches/plant were negatively significant affected by salinity treatment (2000, 4000 mg/L) during the two studied growing seasons. While date of flowering and number of fruits/plant were not affected by treatments of saline irrigation water across the two seasons. Line G3 recorded the highest mean value for average fruit weight/plant followed by Line G4. Fruit shape index, total soluble solids and fruit moisture content were also significantly positive affected by different levels of water saline. These results clearly indicated that the evaluated melon genotypes differed in their genetic traits. Among genotypes, G3 and G4 lines showed the highest tolerance to the saline water treatments (2000 , 4000 mg/L) , so we recommend to use these lines either in areas irrigated with saline water or to be integrated in breeding program to produce more salt tolerant hybrid of melon plant that can be used in cultivating areas irrigated with saline water.

The present investigation was carried out during three years of 2012, 2013 and 2014. These experiments were done at Sabaheya Horticultural Research Station, Alexandria, and Fowa area, Kafer El-Sheikh, Egypt. Type of gene action, correlation coefficient and path analysis among all combinations of some important characteristics of sweet melon were studied. A 5X5 half-diallel cross was performed among five pure lines of sweet melon. Additive gene effects were found to be significant for plant length, number of branches / plant, flowering date, maturity date and flesh thickness indicating that the additive gene action played the main role in the inheritance of these traits. The evaluated characteristics of fruit netting, fruit shape index, total soluble solids % and moisture content exhibited insignificant values for the additive gene action. The dominant gene effect was found to be significant for plant length, number of branches per plant, maturity date, fruit netting degree, Total soluble solids % and moisture content indicating the importance of dominant gene effect in the inheritance of this characters. Total yield per plant, phenotypically, correlated with plant length, average fruit number and average fruit weight. Hence, a lot of attention for such relationships in the improvement program of such characters of sweet melon through selection.