Department of Soil Science and Agricultural Chemistry, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore - 641 003, India.
Key words: boron, calcium, chemical composition, copper, crop yield, databases, grapes, iron, magnesium, manganese, mineral content, nitrogen, nutrient content, phosphorus, plant composition, plant nutrition, potassium, sodium, sulfur, zinc
Journal of Applied Horticulture, 2003, volume 5, issue 2, pages 76-80.
Abstract: The Compositional Nutrient Diagnosis (CND) and Diagnosis and Recommendation Integrated System (DRIS) nutrient index ranges were derived from a Muscat grape database to relate nutrient concentration and indexes with berry yield. A Muscat grape database of 188 observations on commercial yields and N, P, K, Ca, Mg, Na, S, B, Zn, Cu, Fe and Mn were taken. The proportion of low-yield specimens in the survey population was computed at inflection point of variance ratio function and was associated with a Cate and Nelson statistical value (r2) of 4.7 that was confirmed in the validation subpopulation. Critical CND nutrient indexes were found to be symmetrical about zero as follows: -0.45 to +0.45 for CND/N, -0.39 to +0.39 for CND/P, -0.45 to +0.45 for CND/K, -0.93 to +0.93 for CND/Na, -0.45 to +0.45 for CND/Ca, -0.33 to +0.33 for CND/Mg, -0.60 to +0.60 for CND/S, -1.02 to +1.02 for CND/B, -0.58 to +0.58 for CND/Zn, -0.78 to +0.78 for CND/Cu, -0.55 to +0.55 for CND/Fe, -0.16 to +0.16 for CND/Mn and -0.49 to +0.49 for
