冬播作物(大麦、小麦、油菜、蚕豌豆)在0℃以下的低温下,极易遭受冻害,轻则减产,重则死苗。尤以瘦弱或拔节的大小麦苗,分枝过多的蚕豌豆和肥嫩多叶的油菜苗,其受害程度更为严重。冻害均系低温引起,冻害表现形式,为叶部受冻,呈现水渍状(象开水烫过一样)而后枯萎;二为根部抬起(称根拔),然后整 Winter sowing crops (barley, wheat, rape, silkworm peas) at 0 ℃ below the low temperature, vulnerable to frost damage, ranging from the reduction of production, heavy dead seedlings. Especially thin or jointed wheat seedlings, too many branches of silkworm peas and more tender leafy rape seedlings, the extent of the damage is more serious. Frost damage are caused by low temperature, frost damage manifestations of leaf frost, showing water-like (like boiling water and the same) and then wilt; two for the root lift (said root), and then