SPRING SUMMER BONUS MAGAZINE 2026

tion of Calcinator™ (1L/100 L), and Kelpura™ (500 ml/100 L). Figure 3. Change in leaf calcium concentration (% Ca) measured 72 hours after foliar application of Kelpura™ (500 ml/100 L) and Calcium nitrate (200 kg/ha) treatments. 1.5 1.7 1.9 2.1 2.3 2.5 2.7 2.9 3.1 3.3 3.5 24h 48h 72h %Ca in leaf tissue Control CALCINATOR™ KELPURA™+CALCINATOR™ Figure2. Calciumconcentration (%Ca in leaf tissue)over time following foliar applicationofCalcinator™ (1L/100L),andKelpura™ (500ml/100L). 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Control Ca(NO₃)₂ KELPURA™+Ca(NO₃)₂ Change in%LeafCalciumafter72hrs Figure3. Change in leafcalcium concentration (%Ca)measured72hoursafter foliarapplicationofKelpura™ (500ml/100L)andCalciumnitrate (200kg/ha) treatments. Rochelle Thuynsma, Head of Products: Technical Agri Technovation Figure 2: Calcium concentration (% Ca in leaf tissue) over time following foliar application of CALCINATOR™ (1 L/100 L), and KELPURA™ (500 ml/100 L). Figure 3: Change in leaf calcium concentration (% Ca) measured 72 hours after foliar application of KELPURA™ (500 ml/100 L) and calcium nitrate (200 kg/ha) treatments. Driving calcium efficiency with KELPURA™ This effect is reflected in calcium uptake dynamics following foliar application. Across measured time points, the combination of KELPURA™ with CALCINATOR™ resulted in consistently higher calcium accumulation in leaf tissue, when compared to both the untreated control and CALCINATOR™ alone (Figure 2). Calcium levels increased rapidly following application, reaching a higher peak, and remaining elevated, relative to other treatments. In contrast, the control showed limited calcium accumulation, while CALCINATOR™ alone improved uptake, but did not achieve the same magnitude or consistency as the combined treatment. These differences were maintained over time and translated into final calcium status. After 72 hours, the increase in leaf calcium was greatest where KELPURA™ was included with CALCINATOR™, confirming that calcium efficiency is determined not only by supply, but by the plant’s ability to absorb, transport, and utilise that supply effectively (Figures 2 and 3). Comparative evaluation across treatments further supports this response, where calcium levels in leaf tissue after 72 hours remained highest under the KELPURA™ + CALCINATOR™ programme, relative to all other treatments evaluated (Figure 4). This reinforces the consistency of the response and the role of KELPURA™ in improving overall calcium utilisation. The phenolic fraction of KELPURA™, including cinnamic acid derivatives such as p-coumaric and ferulic acid, interacts directly with the structural environment of the cell wall. These compounds are part of the same biochemical system that governs cell wall reinforcement, where ferulic acid forms cross-links between polysaccharides and lignin-associated structures, increasing rigidity and defining wall permeability (Fry, 1986; Boerjan et al., 2003; Ralph et al., 2004). >> www.agribonus.co.za Spring/Summer 2026 BONUS 129