Considering a scenario where there is a low availability and increasing costs of fertilizers in the global agricultural market, as well as a finitude of important natural resources, such as phosphorus (P), this study tested the effect of the inoculation of rhizospheric or endophytic microorganisms isolated from Hymenaea courbaril and Butia purpurascens on the growth promotion of Glycine max (L.) Merr. The tests were conducted in a controlled greenhouse system, and the effects of biofertilization were evaluated using the following parameters: dry biomass, nutritional content, and photochemical and photosynthetic performance of plants. Seed biopriming was performed with four bacterial and four fungal isolates, and the results were compared to those of seeds treated with the commercial product Biomaphos^®. Overall, microbial inoculation had a positive effect on biomass accumulation in G. max, especially in strains PA12 (Paenibacillus alvei), SC5 (Bacillus cereus), and SC15 (Penicillium sheari). The non-inoculated control plants accumulated less nutrients, both in the whole plant and aerial part, and had reduced chlorophyll index and low photosynthetic rate (A) and photochemical efficiency. Strains PA12 (P. alvei), SC5 (B. cereus), and 328EF (Codinaeopsis sp.) stood out in the optimization of nutrient concentration, transpiration rate, and stomatal conductance. Plants inoculated with the bacterial strains PA12 (P. alvei) and SC5 (B. cereus) and with the fungal strains 328EF (Codinaeopsis sp.) and SC15 (P. sheari) showed the closest pattern to that observed in plants treated with Biomaphos^®, with the same trend of direction of the means associated with chlorophyll index, (A), dry mass, and concentration of important nutrients such as N, P, and Mg. We recommend the use of these isolates in field tests to validate these strains for the production of biological inoculants as part of the portfolio of bioinputs available for G. max.

Although sugarcane yield is directly influenced by the availability of nitrogen (N), the efficiency of mineral N (MN) fertilization is considered to be low due to nitrate leaching and ammonia volatilization. Thus, the search for alternative sources of N that are cheaper and more consistent with sustainable farming practices has been stimulated. As chicken litter is an organic waste with the potential to supply N to major crops, we tested the hypothesis that the use of this litter as a source of organic N (ON) is as efficient as the application of MN (ammonium nitrate) in promoting the growth, nutrition, and yield of sugarcane plants grown during both plant cane and ratoon cane seasons. Experiments were conducted in a 5 × 5 × 2 subdivided plot scheme in the growing area of the Denusa Mill, Destilaria Nova União S/A, located in the midwest region of Brazil, with treatments consisting of five doses each of MN (0, 40, 80, 120, and 160 kg ha⁻¹) and ON (0, 2, 4, 6, and 8 T ha⁻¹), evaluated in two crop seasons (plant cane-2019/2020 and ratoon cane-2020/2021). The application of different doses of MN or ON influenced the height and number of tillers of sugar cane plants, and the application of ON, supplied by chicken litter, to this crop was as efficient as that of MN in promoting plant growth. MN and ON also increased the leaf content of N, P, and K; moreover, the absence of one source of nitrogen was compensated by the other. ON application (up to 4.8 T ha⁻¹) also increased sugarcane yield in addition to promoting growth. Furthermore, this study highlighted the superior quality of the regrowth observed in the IACSP95-5094 cultivar, which manifested in increased tillering and stem diameter, resulting in consistently higher yields in the ratoon crop.

The anthropization of the landscape of the Cerrado biome that has occurred over the past few decades has fragmented its natural environments, impacting the connectivity of the plant populations and altering their gene flow. Plant species may also reduce population size in response to sub-optimal climatic and environmental conditions, and observed distribution patterns may align with theoretical schemes, such as the center–periphery model, that is, it is possible that populations on the edge have lower genetic diversity than center populations, theoretically submitted to environmental conditions closer to the optimum. In this context, we evaluate whether the genetic diversity and inbreeding coefficients of Cerrado plant species are affected by landscape features and climate characteristics, and in particular, if the distribution of the genetic diversity of these plants is consistent with the center–periphery model. To do this, we conducted a literature search for genetic studies of Cerrado plant populations using Scopus, Web of Science, and Scielo databases and the species found were used as a proxy to explore patterns throughout the biome. The data were analyzed using generalized linear mixed models (GLMM) and multiple matrix regressions (MMRRs) to evaluate the effects of landscape features and climatic variables on the observed (H_O) and expected heterozygosity (H_E), allelic richness (AR) and inbreeding (Fis) patterns of the local populations. The landscape was evaluated in terms of the percentage land cover of agriculture (AG), forestry (FO), remnant vegetation (RV), urban areas (UA), pasture (PA), and water (WA) within buffers of 1 km, 3 km, and 5 km around the study populations. We analyzed 121 populations of 31 plant species. The GLMMs showed that H_O was affected by FO regardless of buffer size, while H_E was also affected by FO, but also by WA and UA. AR was affected by WA and UA in all three buffer zones while the Fis was affected by FO and AU. The MMRRs showed that WA may affect H_O, H_E, and Fis within the 1 km buffer, while FO affects H_O and UA affects AR within the 5 km buffer. In the case of the 1 km and 3 km buffers, however, the geographic distance between populations was identified as a factor determining the genetic diversity and inbreeding indices, indicating that isolation by distance may be an important factor defining the breeding patterns of the Cerrado plant populations. The GLMMs and MMRRs also showed that the mean annual temperature (MAT) and, to a lesser extent, isothermality (ISO) can explain the variation in genetic diversity observed in the Cerrado plant populations. We also found that the center–periphery model fits the distribution pattern observed in most of the species evaluated, including Annona crassiflora,Annona coriacea, Copaifera langsdorffii, and Eugenia dysenterica. Our results indicate that changes in the climate and the landscape of Brazilian Cerrado must be considered carefully to guarantee minimizing the impacts of these processes on the genetic diversity of Cerrado plant species and ensuring the long-term conservation of these species in this biome.

Regenerative agriculture and the use of bioinputs have been gaining prominence in the global agribusiness sector, driven by the growing demand for healthier foods produced with minimal impact on ecosystems. In this context, compost and its derivatives (compost extracts and teas) are used to provide effective microorganisms to crops, although production processes affect the efficiency of compost extracts, as well as the soil microbiota. Thus, the hypothesis raised was that the organic matter source used for compost formation affects the agronomic efficiency of compost extracts. The objective of this study was to evaluate the effect of compost extracts based on litterfall of angiosperm (AC) and gymnosperm (GC) species, and the use of inoculation with the nitrogen-fixing bacteria Bradyrhizobium japonicum and Azospirillum brasilense (Bra+Azo), on soil quality, crop growth, grain yield, and disease control in soybean (Glycine max L.) crops. Using AC and GC resulted in varying effects on soybean growth and soil microbial biomass carbon (SMBC), confirming the hypothesis that the organic matter source affects the agronomic efficiency of compost extracts. Plants inoculated with Bra+Azo exhibited higher chlorophyll contents, resulting in a higher photochemical yield than for those treated with compost extracts (AC and GC). However, plants inoculated with AC and GC exhibited high plasticity in mitigating photochemical stress, reaching similar photosynthetic and transpiration rates to those observed in plants inoculated with Bra+Azo. Additionally, inoculation with Bra+Azo, overall, improved the photosynthetic efficiency of soybean plants, and the compost extracts (AC and GC) were more effective than the inoculation with Bra+Azo in increasing soybean 1000-grain weight, probably due to improvements in root development. The growth promotion observed with AC and GC is likely attributed to increases in SMBC by these compounds, denoting improvements in soil quality and biocontrol of damage caused by insect attacks.

The vegetation loss in the Brazil’s Legal Amazon (BLA) in 2020 corresponds to the highest loss observed in a decade, caused by the intensification of fires, mineral extraction activities, and other pressures. The possibility of earning from illegal activities such as deforestation and mining attracts the population to indigenous territories, while fires aggravate respiratory problems and enhance the current COVID-19 crisis. Furthermore, the BLA’s road network is usually related to increased deforestation and fires in its areas of influence, and airports are known to contribute to spreading COVID-19 infections worldwide. Therefore, we decided to evaluate the effect of characteristics of Special Indigenous Health Districts (DSEIs) (including population, number of airports, and extent of the road network) and vegetation loss rates (deforestation, and area of vegetation lost by fires and mining) on the number of COVID-19 cases and deaths among the indigenous population in DSEIs in the BLA. We observed a positive correlation between the number of cases and deaths and the number of Indigenous Primary Healthcare Units, suggesting that many of these units did not increase appropriate activities for prevention and protection from COVID-19 in the DSEIs. The DSEIs with larger air transport and road networks were more affected by COVID-19. These networks constituted critical mechanisms for facilitating the spread of SARS-CoV-2 in the BLA. Additionally, we noted that changes that impact the landscape of DSEIs, such as fires and mining, also impact legal indigenous areas (IAs). Thus, IAs are not spared from exploratory processes in the district’s landscape. Models that associate the air transport and road networks with the transformation of the landscape in IAs from burning or mining can explain the number of indigenous people who died due to COVID-19. These results are particularly important given the current disruptive scenario imposed by the Brazilian government on critical institutions that detect and fight fires in indigenous lands and the policies enacted to combat COVID-19 in Brazil, which are based on denying isolation measures and delaying vaccinations.

Biotic stress in cotton plants caused by the phytopathogenic fungus Colletotrichum gossypii var. cephalosporioides triggers symptoms of ramulosis, a disease characterized by necrotic spots on young leaves, followed by death of the affected branch’s apical meristem, plant growth paralysis, and stimulation of lateral bud production. Severe cases of ramulosis can cause up to 85% yield losses in cotton plantations. Currently, this disease is controlled exclusively by using fungicides. However, few studies have focused on biological alternatives for mitigating the effects of contamination by C. gossypii var. cephalosporioides on cotton plants. Thus, the hypothesis raised is that endophytic fungi isolated from an Arecaceae species (Butia purpurascens), endemic to the Cerrado biome, have the potential to reduce physiological damage caused by ramulosis, decreasing its severity in these plants. This hypothesis was tested using plants grown from seeds contaminated with the pathogen and inoculated with strains of Gibberella moniliformis (BP10EF), Hamigera insecticola (BP33EF), Codinaeopsis sp. (BP328EF), G. moniliformis (BP335EF), and Aspergillus sp. (BP340EF). C. gossypii var. cephalosporioides is a leaf pathogen; thus, the evaluations were focused on leaf parameters: gas exchange, chlorophyll a fluorescence, and oxidative metabolism. The hypothesis that inoculation with endophytic strains can mitigate physiological and photochemical damage caused by ramulosis in cotton was confirmed, as the fungi improved plant growth and stomatal index and density, increased net photosynthetic rate (A) and carboxylation efficiency (A/Ci), and decreased photochemical stress (ABS/RC and DI₀/RC) and oxidative stress by reducing enzyme activity (CAT, SOD, and APX) and the synthesis of malondialdehyde (MDA). Control plants developed leaves with a low adaxial stomatal index and density to reduce colonization of leaf tissues by C. gossypii var. cephalosporioides due to the absence of fungal antagonism. The Codinaeopsis sp. strain BP328EF can efficiently inhibit C. gossypii var. cephalosporioides in vitro (81.11% relative inhibition), improve gas exchange parameters, reduce photochemical stress of chlorophyll-a, and decrease lipid peroxidation in attacked leaves. Thus, BP328EF should be further evaluated for its potential effect as a biological alternative for enhancing the resistance of G. hirsutum plants and minimizing yield losses caused by C. gossypii var. cephalosporioides.