Effect of water deficit stress on growth, yield, fruit quality and water use efficiency of some Iranian melon accessions

In order to evaluate the effect of water stress on growth, yield and fruit quality of some Iranian melon accessions, an experiment was carried out in a split plot based on randomized complete block design with three replicates in research filed of university of Zanjan as during 2015. Treatments consisted arrangement of three irrigation levels (starting irrigation at 100, 70 and 40% ETc) and 8 accessions of Iranian melon (Ghalam Ghash, Roshe, Zerke, Khatooni, Rish Baba, Ghobadloo, Garake and Kalyar). The results showed that water deficit stress significantly reduced growth and fruit yield. The lowest yield (18223.1 kg/ha), fruit weight (1057.94 gr), number of fruits per plant (1.75), leaf area (124.257 cm2) and the highest leaf dry weight (21%) was obtained in water deficit stress 40% ETc. Accessions had different growth and fruit yield. In all accessions, growth and fruit yield was reduced by increasing of water deficit stress but leaf dry weight, TSS and water use efficiency was increased. The highest amount of leaf area (410.279 cm2), yield (49881.33 kg/ha) and fruit weight (2270.9 gr) was obtained in "Ghalam Ghash" under 100% ETc irrigation. Also the maximum water use efficiency was observed in "Khatooni" and "Ghalam Ghash" under water deficit 40% ETc. According to the results, "Zerke" and "Rish Baba" with highest (65.17%) and lowest (41.16 %) yield reduction respectively under irrigation 40% ETc were sensitive and tolerance accession to the water stress compared to normal irrigation.