Arbuscular mycorrhizal fungi on the biomass and nutrition of Urochloa decumbens at different soil densities

Abstract

The objective of this work was to evaluate the influence of arbuscular mycorrhizal fungi (AMF) on the accumulation of shoot and root biomass and on the nutrient contents of Urochloa decumbens grown in soils with different densities. The experiment was carried out in a randomized complete block design, in a 4x2 factorial arrangement: four soil densities (1.0, 1.2, 1.4, and 1.6 kg dm-3) with and without inoculation of AMF, with four replicates. The biomass accumulation (dry matter weight of shoot and roots) and macro- and micronutrient contents of U. decumbens were determined at different soil densities. The mycorrhizal colonization of the plants was evaluated, and the number of mycorrhizal spores present in the soil was determined. The biomass accumulation of shoot and roots and macro- and micronutrient contents, as well as the number of mycorrhizal spores in the soil, were negatively affected by the increase in soil density. Only root biomass increased with AMF inoculation. There was no interaction between soil density and inoculation for shoot and root biomass accumulation. Arbuscular mycorrhizal fungi influence the accumulation of biomass in the roots and of N and Ca contents in the shoots of Urochloa decumbens even at the highest soil densities.

Role of mycorrhizas and root exudates in plant uptake of soil nutrients (calcium, iron, magnesium, and potassium): has the puzzle been completely solved?

“…Thus, studies of the effects of mycorrhizas on N uptake tend to be restricted to N‐limited soils, including young soils, such as in central‐north Europe and North America (Lambers et al., 2008; Makarov, 2019). Although plant N uptake increases with AM fungi (Jentschke et al., 2001; Labidi et al., 2012; Mardukhi et al., 2011; Sales et al., 2018; Verzeaux et al., 2017; Zhu et al., 2016) and N is absorbed mainly as NH 4 + (Lopez‐Pedrosa et al., 2006), it may be more related to the absorption of inorganic N or organic forms released by the hydrolytic action of saprotrophic microorganisms, rather than to the direct release by AM fungi of hydrolytic enzymes (Makarov, 2019). In boreal regions, where plant growth is limited by N, rather than P, EM fungi mobilize polymeric N compounds and acquire amino acids (Plassard et al., 2002; Smith & Read, 2008).…”

Avaliação Da Multiplicação Dos Esporos De Fungos Micorrízicos Arbusculares Na Savana De Alter Do Chão, Pará

“…KEYWORDS: Mycorrhizae, Symbiosis, Spore multiplication. e fertilizantes sintéticos(RODRIGUES et al., 2018; SANTANA et al, 2018;SALES et al, 2018; NUNES et al, 2019).Este estudo é inédito por estudar osFMA da área de savana de Alter do Chão e utilizar a espécie Brachiaria decumbens Stapf. como hospedeira avaliando importantes aspectos da simbiose, como o percentual de infecção das raízes e a densidade esporos produzidos, a fim de indicar possibilidades de utilização desses fungos em futuros estudos biotecnológicos.…”