苹果幼树越冬后枝干失水枯干的现象叫做“抽条”.由于抽条死枝往往造成树冠残缺不全,树形紊乱,延迟结果年限.抽条严重时,可使地上部枝干全部枯死.苹果幼树越冬抽条的主要原因不是低温冻害所致,而是因为幼树越冬前准备不足骤然遇到冷冻所造成的.特别是早春干旱,由于土壤结冻或地温过低,根系不能或极少吸收水分,而地上部枝条蒸腾量较大,从而造成技干失水.当枝条水分降低 After the young apple tree overwintering branch water dry withered phenomenon is called “drawing.” As the pumping of dead branches often result in incomplete crown, tree disorder, delay the results of years.When pumping serious, can make all the branches above the ground dead The main reason for the young apple tree overwintering is not caused by low temperature frost damage, but because the young tree suddenly encounters the problem of freezing when it is insufficiently prepared, especially in early spring drought, because the soil is cold or the ground temperature is too low, the root can not or Rarely absorbed water, while the shoots above the ground transpiration larger, resulting in dry technical water loss .When the branches of water decreased