摘要： 以寿阳县为代表的山西省中部高海拔地区，旱地玉米是主要的粮食作物。使用适宜熟期类型的品种，是种植成败的关键。因种植地域的差异，所用玉米杂交种的熟期类型在中早熟至中晚熟范围内变动，个别地区也能使用早熟类型。如何准确地掌握所用品种的熟期类型，必须选好划分指标。多年试验研究表明，植株叶数、播种至成熟天数、播种至成熟生育期内≥0℃的积温是熟期分类的形态指标、生育指标和生态指标，而植株叶数是最易识别和掌握的指标。

关键词: 玉米, 高海拔地区旱地, 熟期类型, 植株叶数

Abstract: Upland maize is a main cereal crop in Shouyang County, a representative area of high elevation region in Jinyhong Dstrict of Shanxi Province.The key to successful planting of maize is the use of varieties with appropriate mature periods.The hybrid varieties of maize used in this area are medium-early maturing to medium-late maturing varieties because of the difference between growing areas.The early-maturing varieties also can be used in some areas.The classification indes of mature period types must be well-selected for the correct use of mature period types of varieties.Experimental researches carried out for many years show that the number of leaves, the number of days from sowing to maturity, and the accumulated temperature above or than or equals to 0℃ during the growing period from sowing to maturity, constitute the morphological index, growth index, and ecological index for classification of mature periods. The number of leaves is the easiect index to be identified and used.

Key words: Maize, High altitude upland, Mature period, Number of leaves