1994年早春出现的低温天气,使南召17.5%种植面积的小麦遭受冻害.1 冻害原因1.1 春性品种面积较大1994～1995年度,南召春性品种种植面积占全县小麦总种植面积的57.8%.由于春性品种抗寒能力差,早春遇到低温天气,极易受冻害.统计结果表明,绵阳系列、铁河1号、豫麦18等春性品种均受到不同程度冻害;南召麦2号、矮丰3号、郑州8327等冬性、半冬性品种基本未受到冻害.因此,春 Cold weather appearing in early spring in 1994 left 17.5% of the wheat planted in Nanzhao to suffer frost damage.1 The cause of frost damage 1.1 The area of ​​spring varieties was large From 1994 to 1995, the planting area of ​​Nanchong spring varieties accounted for 57.8% Due to poor cold tolerance of spring varieties, cold weather was easily encountered in low temperature in early spring, and the results showed that spring varieties such as Mianyang series, Tiehe 1 and Yumai 18 all suffered frost damage to varying degrees; , Aphrodite 3, Zhengzhou 8327 and other winter, semi-winter varieties basically no frost damage.Therefore, spring