Estudos envolvendo bactérias promotoras de crescimento de plantas vêm chamando cada vez mais atenção no setor agrícola, devido ao seu potencial para melhorar o crescimento, produção e proteger as plantas dos estresses bióticos e abióticos. O presente estudo teve como objetivo avaliar o efeito de três espécies de bactérias promotoras de crescimento de plantas (Bacillus subtilis, Priestia megaterium e Priestia aryabhattai) no crescimento e nos aspectos morfológicos e bioquímicos de plântulas de Gossypium hirsutumL. (algodão). O experimento foi conduzido em casa de vegetação com quatro tratamentos (um controle e três inoculações) e cinco repetições por tratamento. As sementes foram inoculadas por imersão em suspensões bacterianas (109 UFC/mL) e então semeadas em vasos. As plantas foram acompanhadas por 60 dias. Na coleta, as plantas foram mensuradas quanto à massa fresca das raízes e da parte aérea, à altura da parte aérea, ao diâmetro do caule e número de folhas. Amostras foliares foram submetidas às análises bioquímicas. Os resultados obtidos mostraram que sementes tratadas com P. aryabhattai tiveram melhorias significativas nos parâmetros de massa fresca, altura da planta, diâmetro do caule e número de folhas e nos teores de clorofila (a, b e total), nitrogênio e proteínas em relação às plantas do tratamento controle. Plantas tratadas com P. megaterium também obtiveram melhorias na massa fresca, no diâmetro do caule e nos teores de nitrogênio e proteínas. Esses resultados indicam um potencial dessas bactérias promotoras de crescimento de plantas para utilização em culturas do algodão, podendo ser empregadas na elaboração de bioestimulantes e biofertilizantes.

Soil microbiota is an important component of the forest biomes, playing important roles in the soil aggregation and cycling of nutrients. Among the soil microorganisms stand out the yeasts, which are unicellular fungi involved in important soil ecological processes. The Brazilian Atlantic Forest is one of the main biodiversity hotspots in the world, and the effect of altitudinal gradient on the distribution patterns of yeast species across this ecosystem has not yet been addressed. Thus, this study aimed to [...] ABSTRACT Soil microbiota is an important component of the forest biomes, playing important roles in the soil aggregation and cycling of nutrients. Among the soil microorganisms stand out the yeasts, which are unicellular fungi involved in important soil ecological processes. The Brazilian Atlantic Forest is one of the main biodiversity hotspots in the world, and the effect of altitudinal gradient on the distribution patterns of yeast species across this ecosystem has not yet been addressed. Thus, this study aimed to

Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) is a pest that can be highly destructive to cotton, Gossypium hirsutum. Transgenic plants technology have increasingly been used as a means of control. In this context, the aim of this study was to evaluate the mortality of 1st and 3rd instar larvae of S. frugiperda fed with leaves and flower buds from two Bt cotton cultivars (Cry1Ab+Cry2Ae and Cry1Ac+Cry2Ab2). Plant parts were collected in the field to provide to the larvae. The leaves were exposed to the 1st and 3rd instar larvae (10 replications of three larvae each) and the flower buds to the 3rd instar larvae (4 replications of five larvae each), which were kept in a climate-controlled room (25 ± 2 °C, 75 ± 10% RH, and 12:12 h photoperiod). The trials were carried out in a completely randomized design (CRD). Mortality was analyzed at 72, 96, and 120 hours after supplying the plant parts. There was no significant difference in the mortality of 1st and 3rd instar larvae between the Bt cultivars when the plant parts were supplied. A 46% reduction was observed in the mortality of 3rd instar larvae compared to the 1st instar larvae exposed to the leaves. The 3rd instar larvae fed with leaves of Bt cultivars and fed with the reproductive structures of the plant did not differ from each other regarding mortality. Thus, the Bt cotton cultivars evaluated caused mortality of 1st instar S. frugiperda larvae. Therefore, there is a need to adopt complementary tools such as biological control, for example, to control caterpillars in more advanced stages which may remain in these areas planted with Bt crops.

Farmers worldwide use agrochemicals and biological inputs to fertilize fields, manage pests and diseases, and promote plant growth. However, there is still limited field-based evidence on the extent to which biological inputs function as substitutes, incremental complements, or alternatives to agrochemicals in key farming practices. This study presents preliminary results on the use of synthetic and biological inputs for the most common practices employed by large soybean farmers in central Brazil. We combined literature review, regulatory data on registered biological products, and in-person interviews with farmers and market experts. Our results show that, in most practices, biological products are adopted alongside the continued use of synthetic inputs, in some cases reducing the frequency or dosage of chemical applications. Inoculants based on nitrogen-fixing bacteria already substitute mineral nitrogen fertilization in soybean, while biosolubilizers and plant activators are used incrementally to enhance the efficiency of chemical fertilizers. Bioinsecticides and biofungicides are predominantly employed as alternatives within spray programs, especially in preventive or early interventions, thereby reducing the number of conventional pesticide sprays. Bionematicides emerge as the main biological tools used as substitutes for synthetic nematicides in preventive treatments, whereas biological herbicides are not yet available on the market. Field evidence presented in this study showed that farmers adopt biological products in diverse ways, including as substitutes, incremental, or alternatives to chemical products, depending on the technologies available. These findings provide a more nuanced understanding than the common views that, on one hand, biological inputs simply complement rather than substitute chemical products, and on the other, that biological solutions can fully substitute synthetic products. As environmental and economic implications, we conclude that biological inputs can underpin trajectories towards more regenerative management in large-scale soybean systems, even when synthetic inputs remain part of the production matrix.

The demand for fertilizers in agriculture is growing, as is the search for new sources of nutrients that cause less impact on the environment. The use of soil remineralizers, using regional sources of nutrients, stands out in this context. In addition, there is the use of nutrient-solubilizing microorganisms, which release organic acids that increase efficiency and accelerate the availability of nutrients from regional sources with low solubility. Altogether, they promote soil health, conserve natural resources, and minimize negative impacts on ecosystems. Thus, this study evaluated the development of the wheat cultivar BRS 264, using soil remineralizers and regional fertilizers in fertility management and biological products in disease and pest control. The analysis included total productivity and economic viability, measured through operational gross profit indexes. Moreover, soil chemical analysis was conducted before and after cultivation. The results revealed a 14% increase in productivity of the BRS 264 cultivar in an irrigated system with regenerative management and a 27% reduction in total costs per hectare compared to conventional management. The results demonstrate a substantial reduction in total costs per hectare compared to conventional management, suggesting this approach is effective from both agronomic and economic perspectives. These findings suggest that natural nutrient sources combined with biological products can be effective tools in soil fertility management in wheat cultivation.