Effects of irrigation water qualities on biomass and sugar contents of sugar beet and sweet sorghum cultivars.

An experiment involving four qualities of irrigation water two sugar beet and three sweet sorghum cultivars was conducted in a split plot design with four replications at Rudasht Drainage and Reclamation Experiment Station in 1999. The results showed salinity of water has an adverse effect on sugar beet and sweet sorghum biomass. Sweet sorghum cultivar SSV108 had the lowest biomass under all qualities of irrigation water Sweet sorghum cultivar Rio had the maximum biomass with water qualities of 2, 5, and 8 dS m(-1). Sugar beet cultivar 7233 had the maximum biomass with 11 dS m(-1). The effect of irrigation water quality was not significant for sugar characteristics such as brix, pol and purity. However, responses of cultivars on the above parameters were significant and sugar beet cultivars had higher brix, pol and purity and lower invert sugar and starch than sweet sorghum cultivars. In conclusion, sweet sorghum cultivars are not recommended to be irrigated with saline water of more than 8 dS m(-1) for sugar production. Under such condition, they may be suitable to be grown for forage purposes.

Effect of water quality on yield of sugar beet and sweet sorghum.

To study the effects of quality of water on soil and plant, an experiment was conducted at Rudashat Drainage and Reclamation Experiment Station in 1999. Four irrigation water salinities (2, 5, 8 and 11 ds m(-1)) and two sugar crops (sugar beet and sweet sorghum) were used in this experiment. The results showed that under the same water quality, sweet sorghum used 2700 cubic meter per hectare less water than sugar beet. As the quality of irrigation water decreased, the soil salinity and exchangeable sodium percent increased which caused yield reduction for both plants. Sugar beet by accumulating Na and Cl in its leaves tolerated salinity but its usage as a forage crop caused some limitations, whereas sweet sorghum by not accumulating Na and Cl escape salinity and it can be used as a forage crop without any limitation.