2024, Vol. 7, Special Issue 3

author(s)
Savita B, RB Negalur, Sadhana Babar, Heena MS, SS Anjum and Sidharam Patil

abstract
A survey was conducted during 2020-21 in groundnut fields of Indi and Sindagi talukas of Vijayapura district. Leaf samples (n=97) of groundnut (fully matured 1^stpair of leaves at full bloom stage of groundnut) were collected and analysed for macro-and micro-nutrient status. The entire population was divided into two i.e. low- and high-yielding population based on cut-off yield of 6 q/acre. A data bank was established to develop nutrient diagnostic norms and identification of most yield limiting nutrients using Diagnosis and Recommendation Integrated System (DRIS) approach. The DRIS is a dual ratio concept where the nutrient concentration ratios were considered rather than absolute nutrient concentrations in isolation. The results revealed that the mean of groundnut leaf nutrient concentrations of N, P, K and S were 3.20, 0.43, 2.11 and 0.07 percent respectively. Whereas, micronutrients mean of Fe, Mn and Zn were 119.42, 67.65 and 18.72 µg/g respectively in high yielding groundnut fields. Whereas, low yielding groundnut fields, the mean of groundnut leaf nutrient concentrations of N, P, K, S, and Fe, Mn and Zn were 2.86, 0.32, 2.16, 0.06 percent and 119.20, 66.50 and 18.726 µg/g respectively. A total of twenty-one nutrient ratio expressions used as diagnostic norms from high yielding population are provided. The important nutrient ratio expressions were: N/K (1.52), Zn/N (5.86), Fe/K (56.6), Zn/K (8.87), Fe/Zn (6.39) and Mn/Zn (3.62) etc. were from a physiological point of perspective equally significant etc. The diagnosis of nutrient imbalance through DRIS indices indicated that P is most yield limiting nutrient followed by S and Fe in the low yielding groundnut fields.