落叶前根外追肥对苹果休眠期营养状况的影响

本文于落叶前向苹果树根外追施矿质肥料，落叶后采样测定了氨基酸、可溶性糖和Ｐ、Ｋ、Ｂ、Ｃａ的含量。结果表明，喷含Ｃａ２＋、Ｋ＋、ＳＯ２－４、Ｈ２ＰＯ－４、ＮＯ－３及尿素等肥料均使粗根中氨基酸含量下降，除ＳＯ２－４外其它肥料能促进氨基酸由长枝下运至根系；ＫＮＯ３、Ｂ使根枝中可溶性糖含量增加，而Ｋ２ＳＯ４、ＣａＳＯ４、Ｃａ（ＮＯ３）２、ＫＨ２ＰＯ４使其含量下降；根外追肥促进Ｐ在粗根和枝条中贮存，其效果依次是：ＫＨ２ＰＯ４＞Ｋ２ＳＯ４＞尿素＞ＫＮＯ３，ＫＨ２ＰＯ４、尿素促进Ｃａ在短枝中的贮藏；Ｂ在喷肥后略有减少；根外追肥对Ｋ＋在粗根贮藏影响不显著。

THE EFFECT OF LEAF APPLICATION OF FERTILIZER BEFORE LEAF ABSCISSION ON THE NUTRIENT CONDITION OF APPLE TREE IN DORMENT PERIOD

Spraying Ca 2 ,K ,SO 2- 4,H 2PO - 4,NO - 3and Urea on apple tree leaves before leaf abscission, the content of amino acid decreases in thick roots and the fertilizers except SO 2- 4 make amino acid transport from long branches to roots system. All KNO 3 and B erable the soluble carbohydrate to increase in the roots and branches, while K 2SO 4, CaSO 4, Ca(NO 3) 2, and KH 2PO 4 decrease it in roots and shoots. Leaf spraying fertilizer makes P store in thick roots and shoots, and Urea make Ca store in short shoots.The effects are in the following order-KH 2PO 4>K 2SO 4>Urea>KNO 3,KH 2PO 4. The B content decreases a little after leaf spraying.