Diagnosis and recommendation integrated system approach for major and micronutrient diagnostic norms for apple (Malus Domestica Borkh) under varying ages and management practices of apple orchards

摘要

Various approaches for the Diagnosis and Recommendation Integrated System (DRIS) indices were employed like Beaufil's ER, Elwali and Gascho and Jones. As per the Beaufil's approach of DRIS indices, the nutrient requirements in the initial stage of the apple tree were magnesium > nitrogen > sulfur > phosphorus > copper > zinc > iron > manganese > boron > calcium > potassium (Mg > N > S > P > Cu > Zn > Fe > Mn > B > Ca > K) and in the later stage at 40-50years, the nutrient requirements were S > Cu > Mg > Fe > P > N > Ca > Mn > K > Zn > B, thus demanding a foliar application of magnesium salt and urea which are required in high amounts in the initial stage; however in the later stage, the yield depression was not attributed to the nutrient deficiency but rather trees' genetic make-up which destabilizes the higher yield in the period of 50years. Nutrient sufficiency ranges for apple derived from DRIS norms were 1.91-2.24, 0.18-0.26, 1.11-1.61, 1.74-1.88, 0.30-0.33 and 0.28-0.30% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S), respectively.