Fallow is a practice in which the soil is left uncultivated for a period of time and is used less due to the pressure on agricultural land, which impairs soil regeneration. The cultivation of legumes, such as peanuts, is a viable alternative that leads to an improvement in the soil chemistry and grain capacity. Despite their importance, there are gaps regarding the use of peanuts for land reclamation and their importance for enzymatic activity in the soil. Therefore, the aim of this study was to evaluate the effects of straw incorporation and peanut cultivation in fallow land on the soil’s chemical and biological quality and to determine whether the introduction of these elements contributes to an improvement in the soil fertility parameters and enzymatic activity. To achieve these objectives, experimental plots were established in fallow soils with different amounts of straw (0; 5 and 10 t ha⁻¹), with and without herbicide application and with peanut incorporation. The soil chemistry and enzymatic activity, plant biometrics and productivity were evaluated. The results showed that the straw treatment resulted in better plant development and increased productivity by up to 80%. The pH, soil organic matter, soil organic carbon, P, K, sum of bases and cation exchange capacity variables increased significantly with the presence of the plant and the incorporation of straw compared to uncovered soil, by 10%, 86%, 80%, 68%, 42%, 38% and 27%, respectively. For the enzymatic activity, the values showed that straw and peanut management affects the higher activity of β-glucosidase and arylsulfatase, with differences of 75 and 74% compared to the control. The incorporation of straw and peanuts in fallow land improves the chemical and biological quality of the soil. The use of herbicides has no effect on the soil dynamics or peanut development in the presence of straw and the presence of peanuts provides a better soil quality index and increases the β-glucosidase and arylsulfatase activity in the soil.

This systematic review evaluated studies published between 1980 and 2025 on the chemical control of smut grass [ Sporobolus indicus (L.) R. Br.] in the Americas, with a focus on pastures. After 446 publications were screened, 13 peer-reviewed articles met the inclusion criteria. Most studies were conducted in the subtropical United States, particularly in Florida, on bahiagrass ( Paspalum notatum Flueggé) pastures, with only one study carried out in Brazil. The most frequently reported herbicide was hexazinone, present in more than 80% of the studies, applied either alone or in combination with mechanical methods or fertilization. Consistent results indicated control efficacy above 85%, especially at doses ≥0.84 kg ha⁻ ¹ and when applied during summer. Selectivity for use in bahiagrass was considered satisfactory despite temporary phytotoxic symptoms. Integrated strategies, such as herbicide applications combined with nitrogen fertilization, showed potential to restore forage dominance and reduce reinfestation. Other herbicides, such as glyphosate, indaziflam, imazapic, mesotrione, and triazines, were less frequently investigated. Indaziflam, applied preemergence, caused a significant reduction in the seedbank, showing promise for preventive management, given the high dormancy and longevity of S. indicus seeds. The integration of chemical and mechanical control produced variable outcomes: in some cases, mowing before application reduced efficacy, whereas in others, when associated with strategies to remove growing points and subsequent herbicide application, it enhanced control. The scarcity of studies under Brazilian and other tropical or subtropical conditions limits the understanding of this species’ adaptation and the efficiency of management methods across different edaphoclimatic contexts. Expanding research in these regions is crucial for developing effective and sustainable management strategies.

Aquatic macrophyte biomass removed from reservoirs represents a residue with potential for agricultural reuse, but its agronomic effectiveness and environmental safety require evaluation. This study assessed decomposed aquatic macrophyte biomass (DB) as a soil amendment for the initial growth of Joannesia princeps in soils from Piraí (RJ) and Jaboticabal (SP), Brazil. Plants were grown in 50 L pots under a completely randomized design with five replicates, using DB at 10, 20, and 40% of pot volume, applied alone or combined with mineral fertilization, plus a mineral-fertilized control. Soil chemical attributes, plant biometric traits, foliar nutrient concentrations, potentially toxic metals, and principal component analysis were evaluated. Increasing DB rates generally increased soil organic matter, sum of bases, cation exchange capacity, base saturation, and the availability of P, K, Ca, Mg, and micronutrients, while reducing potential acidity and aluminum saturation. Intermediate and high DB rates enhanced plant height, leaf number, leaf area, and dry biomass, although responses varied between locations and fertilization strategies. Ni and Pb remained low, with no consistent accumulation pattern. Overall, decomposed macrophyte biomass improved several soil chemical attributes associated with fertility and promoted the initial growth of J. princeps, supporting its potential use as an organic soil amendment under the evaluated conditions.

Peanut cultivation currently plays a minor role in Portuguese agriculture, despite the country’s favorable soil and climatic conditions. In the Azores archipelago, where agriculture is a key economic activity, peanut production has recently sparked interest among rural producers. Weeds pose a major threat to crop development, particularly for short-cycle species like peanuts. This study aimed to de-termine the period prior to weed interference (PPI) in peanut crops under two row spacings (40 cm and 60 cm) on São Miguel Island, Azores. Eight treatments were established to represent increasing periods of weed coexistence: 0–15, 0–30, 0–45, 0–60, 0–75, and 0–90 days after emergence (DAE), from emergence to harvest, and a weed-free control. A randomized block design with four replicates was used for each spacing. The weed community included eight species, with Cyperus spp., Digitaria spp., Amaranthus blitum, and Portulaca oleracea being the most prevalent. Weed interference throughout the entire cycle led to yield losses exceeding 81% and 86% at 40 cm and 60 cm row spacings, respectively. The PPI, defined at a 5% yield reduction threshold, occurred within the first week of weed coexistence, underscoring the crop’s high sensitivity to competition during early vegetative stages.

Peanut cultivation currently plays a minor role in Portuguese agriculture, despite the country’s favorable soil and climatic conditions. In the Azores archipelago, where agriculture is a key economic activity, peanut production has recently sparked interest among rural producers. Weeds pose a major threat to crop development, particularly for short-cycle species like peanuts. This study aimed to determine the period prior to weed interference (PPI) in peanut crops under two row spacings (40 cm and 60 cm) on São Miguel Island, Azores. Eight treatments were established—0–15, 0–30, 0–45, 0–60, 0–75, 0–90 days after emergence (DAE), full-season coexistence, and a weed-free control—to represent increasing periods of weed competition. A randomized block design with four replicates was used for each spacing. The weed community included eight species, with Cyperus spp., Digitaria spp., Amaranthus blitum, and Portulaca oleracea being the most prevalent. Weed interference throughout the entire cycle led to yield losses exceeding 81% and 86% at 40 cm and 60 cm row spacings, respectively. The PPI was defined at a 5% yield reduction threshold, which is a commonly accepted benchmark in weed science to determine the beginning of the critical period of weed interference.

Black pepper (Piper nigrum L.) is an important crop in Pará, Brazil; however, irrigation management remains one of the main constraints to achieving stable productivity and high essential oil yield. By determining soil water tension for rational irrigation management that ensures high agronomic performance of black pepper, it is possible to optimize irrigation water use efficiency through monitoring critical soil moisture with the aid of tensiometers. This study evaluated yield, water use efficiency (WUE) and essential oil yield of two black pepper genotypes under five soil water tensions (15–55 kPa) using a split-plot experimental design. The Uthirankotta genotype showed higher yield and WUE, reaching maximum values at 35 kPa, whereas the highest essential oil extraction yield occurred at 15 kPa. Positive correlations were observed between essential oil yield and the main productive traits. Therefore, cultivation of the Uthirankotta genotype under tensiometer-based irrigation management is recommended under the edaphoclimatic conditions of Pará, using a critical tension of 35 kPa as a reference to increase productivity and optimize irrigation water use efficiency, considering the differential genotype response to irrigation management under humid tropical conditions.