Spatial Distribution of Pomegranate Aril Paleness and Its Relationship with Some Environmental and Non-Environmental Factors Using Geographic Information System (GIS)

The aim of this research was to prepare a map of the spatial distribution of aril paleness, soil texture, climate, rain gauge centers and salinity of irrigation water and soil of 19 pomegranate orchards in Saveh region to investigate the relationship between these factors with the occurrence and severity of paleness. The results showed that in all orchards, paleness occurred with different severity during two years of study and the severity of the complication was higher in the second year. Also, 68% of the orchards had unsuitable irrigation water and salty soil. According to the meteorological data in the whole region, the average air temperature in the second year was higher than the first year. The results of overlapping the maps with gardens layers showed that 60% of the studied orchards are located in the area with sandy-loam soils; all the gardens are situated in the area with dry climate, and the precipitation center. Generally, the occurrence of aril paleness is not affected by the geographical location of the orchards; but the factors of temperature, salinity of irrigation water and soil and soil texture play a role in the occurrence/severity of this complication in Saveh region. Temperature was directly identified as the main factor in the occurrence and severity of this complication. The salinity of irrigation water and soil together with temperature or each alone has a significant role in the incidence and severity of paleness. Regarding the soil texture, it seems that the role of this factor in the severity of the complication can be considered during the salinity of the soil or irrigation water.