Salt Tolerance of N. Co. Varieties of Sugar Cane. II. Effects of Soil Salinity and Sprinkling on Chemical Composition1

The sugar and mineral contents of ‘N. Co. 293’ and ‘N. Co. 310’ sugar canes, grown at graded salinity levels in greenhouse soil cultures and artificially salinized field plots, were affected differently in the two experiments. Salinity decreased pol percent in the greenhouse cane, which had normal sugar content, but increased the pol percent in the field plots where the cane had abnormally low sucrose. However, even in the greenhouse, reduced cane growth was four times more important in reducing sugar yield than was the reduction in sugar content. The mineral content of cane was increased by salinity, and the increase was more striking in the greenhouse because controls were abnormally low in salt. Overhead sprinkling with saline waters in a greenhouse experiment resulted in very little foliar absorption of salt, equivalent to less than the salt absorbed by cane grown in nonsaline plots in the field.