CARBOHYDRATE CONTENT OF YOUNG ASPARAGUS PLANTS AS AFFECTED BY TEMPERATURE REGIMES

The effects of four temperature regimes on the carbohydrate contents of the shoot and roots of 16-month-old plants of two cvs. of asparagus (cv. UC157 and cv. Junon) were studied. The soluble sugar (sucrose, glucose, fructose) concentration in the shoot was not affected by the temperature treatments and was similar in both cvs. However, the two cvs. differed in their ability to accumulate root fructans under the different temperature regimes. Cv. Junon had the highest root fructan concentration under the 22/17 regime. At higher temperatures its fructan concentration significantly decreased. In contrast, cv. UC157 was able to maintain high fructan concentrations even at the higher temperature regimes. Young seedlings of the two cvs. (8 weeks old), prior to the onset of root fructan accumulation, did not differ in their responses to each temperature regime. The ability to accumulate root fructans at high temperatures may have practical significance and may potentially be used as a tool for early screening of asparagus bred for different environmental conditions.