玉米是山区的重要粮食作物之一,特别在中、高山地带是大春作物的主体。但山区自然条件复杂,垂直气候明显,灾害频繁。春季气温回升迟,不利玉米适时早播全苗;秋季霖雨低温来得早,影响玉米安全扬花和灌浆结实。这是目前山区玉米多处于中低产水平的两大原因。 Corn is one of the important cereal crops in mountainous areas, especially in the middle and upper mountainous areas. However, the natural conditions in mountainous areas are complex with obvious vertical climate and frequent disasters. Spring temperatures rose late, unfavorable corn timely sowing the whole seedlings timely; autumn rain came earlier, affecting the safety of corn flowering and filling strong. This is why there are two major reasons why mountainous maize is currently at low or middle levels.