عنوان مقاله [English]
Water deficit stress is one of the most important environmental factors limitting plant growth and crop production. In order to evaluate the tolerance of two Iranian melons to water deficit stress, an experiment in research filed of University of Zanjan was conducted. Treatments consisted of three Irrigation levels, starting irrigation at (100, 66 and 33 % Crop Evapotranspiration) and two accessions of Iranian cantaloupes (Tile-Zard and Tile-Sabz). In this experiment, total chlorophyll content, carotenoids, proline content, leaf relative water content (RWC), ascorbic acid, peroxidase and catalase activity, yield and water use efficiency (WUE) were evaluated. The results indicated that water deficit stress significantly increased proline content, peroxidase and catalase activity and WUE, but decreased RWC, yield and total chlorophyll content. The highest increase in proline content (34.8 %), catalase (18 %) and proxidase (42.3 %) activity and reduction in yield (61.6 %) and RWC (8 %) was obtained in 33 % ETc Irrigation. There has been significant difference between accesesions in relation to RWC, proline, total chlorophyll and peroxidase and catalase activity. The highest value of yield and WUE was observed in 'Tile-Zard'. According to the interaction results, both accessions, 'Tile-Sabz' and 'Tile-Zard' with 63.6 % and 59.7 % Reduction in fruit yield under deficit water stress, are.