ABSTRACT Sap quick tests are well established in vegetable crops. However, there is less equivalent investigation for perennial crops, such as apple trees. Accessing the nutrient content, as opposed to the foliar analysis, would increase the opportunity of adjusting the fertilization, along the growing cycle. This work evaluates the relation between the NO3 −, K+, Ca2+, Mg2+, PO4 3- and NH4 + contents in apple petiole sap, measured with the RQflex® test strips and laboratory methods to assess the possibility of using this tool with accuracy in in-situ sap analysis. Petiole samples were collected from six apple tree orchards, frozen and pressed. Dilution was mandatory for all nutrient determination, except NO3 −. The dilution factor varied with the stage of the annual cycle. The levels of NO3 −, K+, Mg2+, and Ca2+ followed the same pattern during the growing cycle, with both methods. Regression analysis resulted in high determination coefficients for NO3 − (R2 = 0.85), K+ (R2 = 0.86), Mg2+ (R2 = 0.81) and Ca2+ (R2 = 0.95), between RQflex® and laboratory methods. No equivalent relation was found for ammonium and phosphate determination. These tests can be useful tools for rational fertilization management, mainly in high-density apple orchards. The calcium content in 45 DAFB leaves correlated well with the calcium content in sap at the same timing.

中文翻译：

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苹果属 Borkh Cv 的快速树液营养分析方法。'节日'

摘要 Sap 快速测试在蔬菜作物中得到了很好的验证。然而，对于苹果树等多年生作物的研究较少。与叶面分析相反，获取营养成分将增加在生长周期中调整施肥的机会。这项工作评估了苹果叶柄汁液中 NO3 -、K+、Ca2+、Mg2+、PO4 3- 和 NH4 + 含量之间的关系，使用 RQflex® 测试条和实验室方法测量，以评估在- 现场汁液分析。从六个苹果树果园收集叶柄样品，冷冻和压榨。除 NO3 - 外，所有营养素测定都必须进行稀释。稀释因子随年循环阶段的不同而不同。NO3 -、K+、Mg2+、和 Ca2+ 在生长周期中遵循相同的模式，两种方法。在 RQflex® 和实验室方法之间，回归分析导致 NO3 - (R2 = 0.85)、K+ (R2 = 0.86)、Mg2+ (R2 = 0.81) 和 Ca2+ (R2 = 0.95) 的测定系数很高。未发现铵和磷酸盐测定的等效关系。这些测试可以成为合理施肥管理的有用工具，主要是在高密度苹果园中。45片DAFB叶片中钙含量与同一时间汁液中钙含量的相关性较好。这些测试可以成为合理施肥管理的有用工具，主要是在高密度苹果园中。45片DAFB叶片中钙含量与同一时间汁液中钙含量的相关性较好。这些测试可以成为合理施肥管理的有用工具，主要是在高密度苹果园中。45片DAFB叶片中钙含量与同一时间汁液中钙含量的相关性较好。