Abstract A field experiment was conducted over two consecutive years (2021-22 and 2022-23) to compare the effect (direct and residual) of soil-applied Zn, B, and S and foliar-applied Zn and B fertilization on the productivity, nutrient uptake, and quality of cluster bean and mustard. Thirteen treatments, including varying rates of soil-applied Zn (2.0, 4.0, 6.0 kg ha-1), B (1.0,1.5, 2.0 kg ha-1), and S (20.0, 40.0, 60.0 kg S ha-1) and foliar (B, Zn, and Zn + B) were compared in a completely randomized block design replicated thrice. In cluster bean, significant improvements in fresh pod and green forage yields were observed with 4.0 kg Zn ha-1 and 1.5 kg B ha -1 applications, with higher uptake of B, Zn, and S. These treatments also improved the protein content and yield during both years. In mustard, 60.0 kg S ha-1 and the combined foliar application of B + Zn significantly enhanced seed yield, stover yield, and oil and protein contents. Nutrient uptake also showed marked increases in Zn and S uptake with 4.0–6.0 kg Zn ha-1 and 40.0–60.0 kg S ha-1 applications. Different treatments improved Zn, B, and S use efficiency, with foliar Zn + B performing the best. Soil analysis indicated higher post-harvest availability of Zn, B and S at higher application rates of respective nutrients. It was also found that one-time soil application of Zn, B, and S sustained nutrition for two years in nutrient-depleted soils without yield loss. Graphical Abstract
Pant et al. (Sun,) studied this question.