DRIS and the Nutritional Diagnosis of Fruit Trees

植物營養診斷的方法有很多種，其中葉片分析診斷方法為目前世界上使用最多的一種方法。但由於此方法仍有一些問題存在如無法克服葉齡、品種、砧木與季節等所造成元素濃度的差異，因而有DRIS(Diagnosis and Recommendation Integrated System)系統的推出。DRIS是近年來發展出來植物分析診斷的新關念。它利用營養成分的比例來解釋植物成分分析的結果。理論上這個系統可以辨識所有可能找出來影響植物生育的植物、土壤和環境等因子，並使數量化。這些因子之問的相互關係可以用標準值(norms或稱基準），或DRIS指標(DRIS index)，或營養不平衡指標(NII, Nutritional imbalance Index)等來表示。DRIS的好處有：考慮元素間的平衡、沒有地域性，不必考慮品種間與生育階段的差異以及它可排出限制生育因素的次序等。目前DRIS在幾種農藝作物上，如玉米、大豆等已有成功的實例，但它使用在果樹上的結果則不太一致，本文將做討論。 Among all the nutritional analysis and diagnosis systems used in plant, leaf analysis is the most commonly used one. However, as leaf age, cultivars root stocks, seasons and other factors influences greatly the element concentrations in the leaf, special sampling procedures are used for each cultivar or even individual plant. DRIS (Diagnosis and Recommendation Integrated System) was developed to eliminate the concentrational differences caused by leaf age, cultivars, root stocks, seasons and other factors. It also takes into consideration the balance among nutrient elements and lists the order of limiting importance to yield. Although DRIS has been successfully applied to several agronomical crops, the examples in fruit crops has been few and results contraversial