Effect of low temperature on the sugar and glucosinolate content of rutabaga

Abstract Field and greenhouse studies were conducted to investigate the effects of low temperature on the sugar and glucosinolate concentrations in rutabaga ( Brassica napus spp. rapifera (Metzg.) Sinsk) roots. The low temperature treatments consisted of storing field-harvested roots at 0 and 10°C for 8 weeks, and subjecting greenhouse-grown plants to an 11 day cold treatment (0–12°C). During the storage of roots, the total sugar concentration (sucrose, fructose and glucose) increased rapidly during the first 2 weeks, and then levelled off. The total sugar concentration in roots was not influenced by storage temperature. The low temperature treatment of plants resulted in a 10% increase in the total sugar concentration in roots. Low temperature altered the concentration of several glucosinolates in peeled root and peel tissues, but did not induce a qualitative change in the glucosinolate profile. Changes in the glucosinolate concentrations at low temperature were dependent on the treatment, temperature and the root tissue examined.