关键词: 美洲南瓜, 美洲南瓜, 远缘杂交, 亲和性

Abstract: In order to make a research on chill-resistance of 6 cultivars of bulb in Lily include Tiber、Pollyanna、Sorbonne、Siberia、Ceb Dazzle、Brunello.3℃ can be defined as a fixed point of reference and the changes of the physiological indicators of bulb in Lily can be recorded between 0℃ and -15℃. From the records , a conclusion can be drawn that with the decrease of the temperature ,its electric conductivity increases and its changes can be defined as a "s" style curve. Apply logistic equations to set up regression model,define the semilethal temperature is -8.33315℃、-8.76722℃、-9.14241℃、-10.9918℃、-11.3131℃、-12.6293℃.In this process, bound water/free water is increasing. inaddition, the proline is increasing in the first stage and is decreasing in the later stage.The conclusion about the order of Lily’s chill-resistance is Brunello＞Ceb Dazzle＞Siberia＞Sorbonne＞Tiber＞Pollyanna.