本研究以不同生育期之甘蔗為材料，調查植株之農藝性狀包括植冠高度、葉鮮重、葉乾重、葉水分含量、枯葉部節數、青色部節數、枯色部錘度及青色部錘度等，並以灰關聯理論分析不同生育期之農藝性狀對甘蔗植株青色部成熟度之相關性。灰關聯度與灰關聯序顯示，不同生育期甘蔗植株之農藝性狀對青色部成熟度之貢獻度排序分別為：青色部錘度、葉乾重、植冠高度、枯色部錘度、葉鮮重、青色部節數、葉水分含量及枯葉部節數。依據灰關聯分析的結果，青色部及枯色部錘度、葉乾重、植冠高度為評估甘蔗成熟度之重要輔助指標，可作為甘蔗栽培田間管理之參考。

This study applied grey system theory to analyze the relationship between eight agronomic characters including plant height, leaf fresh weight, leaf dry weight, leaf water content, internodes number of dead-leaf stalk, internodes number of green-leaf stalk, juice brix of dead-leaf stalk and juice brix of green-leaf stalk, and the maturity of sugarcane. The contribution degrees of agronomic characters, indicated by grey order, to maturity of sugarcane were: juice brix of green-leaf stalk > leaf dry weight > juice brix of dead-leaf stalk > plant height > internodes number of green-leaf stalk > leaf fresh weight > leaf water content > internodes number of dead-leaf stalk. Therefore, the juice brix of green-leaf stalk and dead-leaf stalk, leaf dry weight and plant height were the most critical characters to the maturity of sugarcane. The result based on grey relational analysis might be used as a valuable reference on the field management of sugarcane.