evaluation of land suitability and potential yield determination of sugar beet in yekanat plain of marand

the main objective of this research was the measurement of soil characteristics, land evaluation and determination of potential yield of sugar beet in yekanat plain of marand. for doing this, firstly, yield potential of sugar beet was estimated by fao method and secondly land evaluation of different soil units for sugar beet cultivation was determined by parametric method. results showed that marand region is not a suitable area for rainfed sugar beet cultivation because the growing period of this region is shorter than that of sugar beet. however, the region does restrict the production of irrigated sugar beet. potential root yield of sugar beet was estimated about 77 ton/ha by applying fao method. evaluation of land units using parametric method showed that the whole studied area can be classified into 5.8% moderately suitable(s2), 26.75% suitable but low profitable(s3) and 52.9% unsuitable (n) classes. strong correlation between parametrically calculated land index and observed yield (r2=0.86) indicated the high accuracy of this method for land evaluation. soil salinity is the main limiting factor for sugar beet cultivation in this area. topography, slope of lands, soil coarse fragments and weak field management can be mentioned as other factors in yield decrease.