Weed Interference in Soybean Crop Affects Soil Microbial Activity and Biomass

Abstract

<jats:p>ABSTRACT: Weeds and microorganisms interacting with their rhizosphere may influence nutrient absorption, which is an important factor for plant competition. The purpose of this study was to evaluate the microbiological activity, inorganic phosphorus solubilization (Pi) and acid phosphatase in the cultivated soil, in a combination of soybean (Glycine max) plants and weeds. Soybeans were cultivated in monoculture and in competition with Bidens pilosa, Brachiaria decumbens (Syn. Urochloa decumbens) and Eleusine indica, under two conditions: a) plants competing without contact between the roots b) plants competing with contact between the roots. A nylon screen with a 50 µm mesh was added to prevent contact between the roots of the species in competition so that the substratum could be separated in the vase. The experiment was conducted in randomized blocks, with four replications. The soybeans in competition with weeds led to lower oxidation of organic matter per unit of microbial biomass, resulting in a lower metabolic quotient, compared with the soybean monoculture. The contact between soybean roots and B. pilosa, B. decumbens and E. indica maintained a strong influence, raising the solubilization of Pi, respectively valued at 51, 39 and 31% in relation to the cultivation of each species with a nylon screen. Microbiological activity, inorganic phosphorus solubilization and acid phosphatase were altered by plant species, combinations of weeds and soybean plants in competition; by root contact in some cases. Thus, the microbiological activity of the soil can influence competition strategies and plant development.</jats:p>

Cover crops on soil quality and yield of cowpea under no-tillage in the Amazon savanna

“…Moreover, the content of this element was higher in the second cycle, regardless of the cover crop. Spontaneous vegetation could not immobilize mineral P, transforming it into organic P. Therefore, it remained in the form of available P, unlike the other crops, which presented higher straw and immobilized more P. This fact becomes important, as it stimulates microbial activity by increasing phosphatase activity (Fialho et al, 2020).…”

Soil microbiological indicators in Coffea arabica crops under different weed management strategies

“…Microbial biomass is an indicator that can be changed by the coexistence and competition with different plant species, the change in soil microbial activity may be due to this competition between plants that affects the microbial community (Fialho et al, 2020). The process of transforming soil organic matter and microbial biomass is directly related to maintaining the productivity of agricultural ecosystems.…”

“…1), demonstrating a lower imbalance of the soil microbiota. That is, low qCO 2 indicates savings in the energy use of the microbial cell, re ecting a more stable environment and closer to its equilibrium state (Fialho et al, 2020).…”

Relationship among Soil Biophysicochemical Properties, Agricultural Practices and Climate Factors Influencing Soil Phosphatase Activity in Agricultural Land

“…Importantly, any adverse effects from herbicide use typically do not persist beyond 30 days after application [184]. However, cultivating crops in competition with weeds compared with weeds cultivated alone negatively impacts ACP activity, microbial activity, and inorganic P solubilization [185]. A number of single and meta-analysis/review studies reported the direction of ACP and ALP responses to pest and weed management, irrigation, crop-livestock, and grazing management.…”