Multivariate interpretation of the foliar chemical composition of essential nutrients in mango under Peninsular India

The nutrient concentration vs yield performance data bank was established for Alphonso mango grownin Peninsular India to develop multivariate diagnostic norms with high diagnostic sensitivity. Well performingorchards in Ramanagara, Srinivaspur, Chittoor, Krishnagiri, Vengurla and Ratnagiri regions were intensivelysurveyed to develop the data bank. The diagnostic norms for N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, b and Mo weredeveloped by using compositional nutrient diagnosis (CND) technique. The interactions among different nutrients were elucidated by principal component analysis (PCA). It was evident that wide variation in plant nutrientconcentration exists in different geographic locations. The mean N concentration showed wide variations from1.03% to 2.87%, P from 0.09 to 0.33% and that of K from 0.78 to 1.35% depending upon the geographic location. Among the micronutrients, Zn concentration showed variation from 14.01 to 24.97 mg kg⁻¹ and b from 3.50 to 16.63 mg kg⁻¹. The CND norms showed higher diagnostic precision compared to the bivariate techniques. Theapplication of PCA indicated that as many as eight nutrient elements were found integrated with first principal component in many locations. Involvement of several nutrients in a single principal component indicated thatit was not possible to diagnose nutrient imbalance of any particular nutrient in isolation in mango and multinutrient involvement on governing yield potential. The extent to which a particular nutrient interacting with other nutrients was a function of nutrient in question and geographic location. The nutrient interaction observed fordifferent locations in general mimicked nutrient behaviour reported earlier. There is a need for integration of the all nutrients for diagnosis of nutrient imbalance in high performing fruit crop like mango.