effect of sodium chloride concentrations and its foliar application time on quantitative and qualitative characteristics of pomegranate fruit (punica granatum l.) cv. “malas saveh”

introduction: pomegranate (punica granatum l.) belong to punicaceae family is native to iran and grown extensively in arid and semi-arid regions worldwide. pomegranate is also important in human medicine and its components have a wide range of clinical applications. cracking causes a major fruit loss, which is a serious commercial loss to farmers. fruit cracking, seems to be a problem that lessens the marketability to a great extent. fruit cracking is one of the physiological disorders wherever pomegranate trees are grown. it may be due to moisture imbalances as this fruit is very sensitive to variation in soil moisture prolonged drought causes hardening of skin and if this is followed by heavy irrigation the pulp grows then skin grows and cracks. many factors i.e., climate, soil and irrigation, varieties, pruning, insects and nutrition statues influence the growth and production of fruit trees. deficiencies of various nutrients are related to soil types, plants and even to various cultivars. most nutrients are readily fixed in soil having different ph. plant roots are unable to absorb these nutrients adequately from the dry topsoil. foliar fertilization is particularly useful under conditions where the absorption of nutrients through the soil and this difficult situation to be present in the nutrients such as calcium. since the calcium element is needed, so spraying them at the right time is correct way to save the plant requirements. therefore, a research conducted on effect of sodium chloride concentrations and its foliar application time on quantitative and qualitative characteristics of pomegranate fruit (punica granatum l.) cv. “malas saveh”. materials and methods: an experiment conducted at jarghoyeh, esfahan, iran in 2012. the factors were sodium chloride (0, 5 and 10 g/l) and times of spray (15, 45 and 75 days before harvest). the study was factorial experiment in the base of randomized complete blocks design with three replications. the measured traits were cracking and sun scald percentage, seed dry and fresh weight, total fruit weight, vitamin c and titratable acidity (ta) using titration method, total soluble solids (tss) using hand refractometer, skin fruit firmness using hand penetrometre, ph using ph meter and dry material. data analyzed using sas and mstat-c statistical program and means compared using an lsd test (p < 0.05). results and discussion: analysis of variance showed that calcium chloride had significant effect on creaking percentage. mean comparison was conducted using lsd range test (at 5% level). sodium chloride decreased cracking percentage compared to control. different stages of sodium chloride application show significant effect on cracking percentage. sodium chloride decreased the cracking rate by increasing of its concentrations. effect of calcium chloride was significant on sun scald. the lowest sun scald occurred inthe second time and the highest in the third time of calcium chloride spraying. the effects of sodium chloride at different stages and concentrations were significant on the total fruit weight and seed fresh weight. the highest total fruit weight and seed fresh weight obtained in the first time and the lowest in the third time of calcium chloride spraying. the effects of sodium chloride at different stages and concentrations were significant on the skin firmness. the highest skin firmness obtained in the third time of calcium chloride spraying and 10 sodium chloride concentrations and the lowest in the first time of calcium chloride spraying and control. the time of calcium chloride spraying had significant effect on total acidity, ph and vitamin c. the highest and lowest fruit total acidity and ph obtained in first and third time of calcium chloride spraying, respectively. however, the highest and lowest fruit vitamin c observed in third and first time of calcium chloride spraying, respectively. fruits treated with sodium chloride showed a reduction in vitamin c and fruit firmness, but increased total soluble solids (tss). in fruit traits increased by higher sodium concentration and earlier spraying time. in addition, later spraying time increased fruit skin firmness conclusion sodium chloride decreased cracking and sun scald percentage quantitative. conclusion: in conclusion, higher sodium chloride concentration reduced fruit creaking and sun scald. in addition, earlier time and higher sodium chloride concentration caused improve quantitative fruit traits. finally, skin firmness increased with higher sodium chloride concentration and later spraying time.