Physiological and Biochemical Characteristics Related to Cold Resistance in Sugarcane

In order to screen the cold tolerant sugarcane varieties, in Ziyuan County, one of the coldest counties having longest duration for frost and snow, in Guangxi province we comprehensively evaluated 21 sugarcane varieties using subordinate function method combined with correlation analyses based on six physiological and biochemical indexes relevant to cold tolerance under natural conditions. It was found that different sugarcane varieties had different responses to the long duration of continuous cold stress, which were dull for soluble protein, proline and malondialdehyde contents. Based on the analysis by subordinate function method, we divided the tested varieties into three groups of cold tolerance. The group I had four varieties with high cold tolerance, the group II had ten varieties with moderate cold tolerance, and the group III had seven varieties with low cold resistance. It is feasible to evaluate the cold resistance at processing maturing stage by using subordinate function method with multiple physiological and biochemical indexes, which can reveal the differences of cold hardiness in different sugarcane varieties, and provide good references for commercial sugarcane production.