Nutritional Efficiency and Nutrient Acumulation of Maize Cultivated in Soils With High Al-KCl Content

Abstract

Most Brazilian soils are weathered and acidic, generally with exchangeable aluminum levels toxic to plants. Aluminum content can exceed 10 cmolc kg-1 in certain soils, but does not interfere in plant nutrient absorption, transport and accumulation. This study aimed to assess whether the high aluminum levels extracted with 1 mol L-1 KCl solution affect the nutritional efficiency of maize plants grown in acidic soils in areas of Brazilian states (AC: profile 9, PE, SC and RS) never before cultivated. To that end, two greenhouse experiments were performed (soybean: 45 days and maize: 60 days) with increasing levels of lime (0; 25; 50 and 100% H+Al content). After the experiments and collection, chemical analyses were conducted to characterize the soils and determine the chemical composition of the maize plants. The Al levels did not interfere in maize plants, nutrient absorption, transport, use or accumulation in AC9 and Rosario do Sul (RS) soils, but did affect those cultivated in PE, BR and CB soils in treatments without lime. The absence of Al toxicity is related to the increased concentration and activity of basic cations and P in the soil solution.

Chemical composition of soybean seeds subjected to fertilization with rock dusts

“…The low Mg contents of the seeds in both soils compared to the other nutrients (except Ca) (Table 4) may be related to its competition with K and Ca for the absorption sites in the plant roots (Senbayram, Gransee, Wahle, & Thiel, 2015;Bruns, 2016;Cunha et al, 2019). Senbayram et al (2015) reported that K absorption by plants is usually not impaired in soils whose Mg contents are higher than the K contents, as observed in this Acta Scientiarum.…”

“…The similarity between the control, pure siltstone, and tephrite treatments may be related to the nutrient dilution (Colombari, Lanna, Guimarães, Martins, & Cardoso, 2018;Cunha et al, 2019) in the plants cultivated in soils managed with limestone, olivine melilitite, and siltstone + olivine melilitite associated or not with manure at their respective doses, which presented the highest TDM productions (Table 5) compared to the other treatments of pods and seeds (data not shown). In addition, the low TDM production may have led to a higher nutrient concentration, but statistically similar to the control (Table 5), in the different parts of the plant cultivated in the soils subjected to the treatments with the rock dusts siltstone and tephrite.…”

“…The nutrient content accumulated in the grains was calculated from these results and the seed weight, using the equation adapted from Cunha, Almeida, Souza, and Ernani (2019).…”

“…In general, the Ca contents in the seeds were lower than the other nutrients, regardless of the soil, treatment, and applied product (Table 4). This behavior is probably related to the low Ca mobility (Domingos, Lima, & Braccini, 2015;Fioreze, Tochetto, Coelho, & Melo, 2018;Cunha et al, 2019) due to the functions it has in the different plant structures, such as calcium pectate formation (cell wall strengthening), plasma membrane stabilization (plasmalemma), root growth (Yamamoto, Ferreira, Fernandes, Albuquerque, & Alves, 2011;Fioreze et al, 2018), and Ca accumulation in the endoplasmic reticulum, chloroplasts, and vacuoles (Zeng, Zhang, Zhang, Pi, & Zhu, 2017).…”

Potential of olivine melilitite as a soil remineralizer according to particle size and rates

“…From TDM and the N, P, K, Ca, and Mg contents, the accumulated amounts of these nutrients in the plant tissue were calculated according to the equation: N Amacro (mg) = TDM (mg) x nutrient concentration (%) / 100 (Cunha et al, 2019), where N Amacro corresponds to the amount of macronutrient accumulated in the vegetal tissue (aerial part + roots) of the tested plants.…”