Critical Dilution Curves for Nitrogen, Phosphorus, and Potassium in Potato Group Andigenum

Abstract

Core Ideas Diagnostics of mineral nutrition in field is poorly developed for potato group Andigenum. Critical dilution curves for N, P, and K were validated in potato group Andigenum. The critical dilution curve serve to identify macronutrient status and to predict yield of potato in the tropics. The critical dilution curves (CDC) for nitrogen (Nc), phosphorus (Pc), and potassium (Kc) obtained from total dry biomass (W) and leaf area index (LAI) were used as a diagnostic tool to determine nutrient status and to adjust fertilization rates in two cultivars of potato (Solanum tuberosum L.) group Andigenum. The research determined allometric ratios of Nc, Pc, and Kc (%) and nutrition index (NI) based on W and LAI in cultivars Diacol Capiro (Capiro) and Pastusa Suprema (Suprema). Additionally, optimal fertilization rate was evaluated to achieve maximum yields during two growth cycles in contrasting environments of the Andean zone of Colombia. The CDC was validated using W in Capiro: Nc = 6.23W −0.320; Pc = 0.523W −0.198; Kc = 9.02W −0.269 and in Suprema: Nc = 6.74 W −0.327; Pc = 0.536W −0.186; Kc = 6.58W −0.135 and presented higher robustness than the CDC obtained from LAI. Capiro presented a lower dilution coefficient b for Kc than Suprema. The NI ranged between 0.25 and 1.32 with better fit in Capiro and relative yields (RY) starting from 40% without fertilization; for Suprema, null to marginal response to fertilization was obtained, indicating a luxury uptake of N (NI 1–1.5) with RY starting from 70%. Except for this research, Nc, Pc, and Kc have not been validated for cultivars of group Andigenum. The CDC for this cultivated group could serve to identify deficiency, sufficiency, or excess of N, P, and K, and to predict final yield per cultivar under highland equatorial conditions.

Effect of slow‐release nitrogen on the nitrogen availability in an andisol and the critical nitrogen concentration in wheat

“…The principles of the critical dilution curve are restricted to the vegetative period of cereal crops, and hence the N nutrition index can be used as a diagnostic tool for wheat until anthesis, crop flowering phase (Justes, Mary, Meynard, Machet, & Thelier‐Huché, 1994; Sadras & Lemaire, 2014). The critical nitrogen concentration (N c ) used to determine the dilution curve based on shoot biomass production have been successfully applied in diverse crops species (Chakwizira, de Ruiter, Maley, & Teixeira, 2016; Gastal et al., 2015; Gόmez, Magnitskiy, & Rodriguez, 2019; Zhao, 2014). However, recent studies have shown that these curves must be adjusted for different environments (Hoogmoed & Sadras, 2016), agronomic management systems (Reyes et al., 2015), organ specific dry matter contents (Zhao et al., 2016), leaf area durations (Wang et al., 2017), and water stress in crops (Hoogmoed & Sadras, 2018).…”

Growing out of hunger: towards an improved understanding of the water and nutrient limited yield of cassava

“…Also, nutrient concentration of plants decreases during the growth cycle, even when nutrient supply is sufficient (Justes et al, 1994;Lemaire, 2012). The concept of nutrient dilution and nutrition index for nitrogen (N) have been widely used as a diagnostic tool for crop N sufficiency, but only few studies are available for other macronutrients (Zamuner et al, 2016;Gómez et al, 2018). To our knowledge, none exists for cassava.…”

“…Also, nutrient dilution curves at maximum growth rates were determined using eq. 2, following the procedure adapted from Gómez et al (2018) for potato, Justes et al (1994) and Lemaire (2012) for winter wheat and various crops and grasses. This required identification of values by which the evaluated nutrients do not limit crop growth (Greenwood et al, 1986;Justes et al, 1994;Marouani et al, 2014).…”

“…The minimum nutrient concentration required by the crop to reach its maximum growth rate at a given amount of biomass accumulation, time and field situation is referred to as critical value (c) of the mineral nutrient (Nc, Pc and Kc). The concept of critical nutrient concentration and nutrition index have been widely used as a diagnostic tool for crop nutrient sufficiency, and to simulate crop demand for nutrients (Justes et al, 1994;Lemaire, 2012;Gómez et al, 2018). The N critical dilution curve based on total biomass has been established for various crops, e.g., wheat (Justes et al, 1994;Yue et al, 2012), corn (Plénet and Lemaire, 1999), rice (Sheehy et al, 1998;He et al, 2017), and potato (Marouani et al, 2014;Gómez et al, 2018).…”

“…The concept of critical nutrient concentration and nutrition index have been widely used as a diagnostic tool for crop nutrient sufficiency, and to simulate crop demand for nutrients (Justes et al, 1994;Lemaire, 2012;Gómez et al, 2018). The N critical dilution curve based on total biomass has been established for various crops, e.g., wheat (Justes et al, 1994;Yue et al, 2012), corn (Plénet and Lemaire, 1999), rice (Sheehy et al, 1998;He et al, 2017), and potato (Marouani et al, 2014;Gómez et al, 2018). A few studies have established critical nutrient dilution curves of other macronutrients for potato (Zamuner et al, 2016;Gómez et al, 2018) and we are unaware of any published reports on critical concentrations of N, P and K in cassava.…”