Fertilization management is essential for forage production. However, excessive use of synthetic fertilizers causes environmental imbalances. An alternative to reduce these effects is to seek alternative fertilizers, such as wood ash produced from agro-industrial waste, when integrated with appropriate base saturation management. This study aims to compare the effects of fertilization with wood ash (WA), organomineral (OM), and mineral (M) fertilizers associated with different levels of base saturation on the growth and water productivity of Panicum maximum cv. BRS Zuri. The experiment was conducted in a greenhouse, using a randomized block design in a 3 × 3 factorial arrangement. The treatments consisted of three types of fertilization (WA, OM and M) and three levels of base saturation (0, 25%, and 50%). Leaf area, chlorophyll index, shoot dry mass and root dry mass, water consumption, and water productivity of Zuri grass were evaluated. The results showed significant increases in leaf area, with values of up to 4564.5 cm².pot⁻¹ and a chlorophyll index of up to 36.2 units. In addition, the dry mass of the aerial part reached up to 46.7 g.pot⁻¹, and the dry mass of the roots reached 21.7 g.pot⁻¹ with the use of OM fertilizers. These values represent an increase of between 43.1% and 69.6% compared to the values of conventional fertilizers. In addition, water productivity reached 4.9 g.L⁻¹ with WA-based fertilizers, an increase of around 39% compared to the values of mineral fertilizers.

Quantifying crop water consumption is essential for water resource management. The objective was to estimate the current evapotranspiration (ET_a) of the cotton crop (Gossypium hirsutum L.) in the rainfed system, as well as the components of the radiation and energy balance in the Cerrado biome conditions using orbital images and the SEBAL algorithm and validate the estimates of evapotranspiration (ET) using FAO guidelines for crop coefficient (K_c) of the cotton crop. Research was carried out in the State of Mato Grosso, Brazil, in areas with three cotton cultivars. Images of the OLI (Operational Land Imager) and TIRS (Thermal Infrared Sensor) sensors were used and ET estimation was made based on the SEBAL algorithm. Mean ET_a in the cotton cycle was 3.5 mm dia⁻¹ and the K_c values ranged from 0.22 and 1.12, on average, in the smaller and larger leaf area, respectively.

Plant resistance to drought stress is a parameter that should be studied with more emphasis in the search for higher agricultural yields. In this scenario, research within breeding programs should be directed toward specific mechanisms of action and important agricultural crops in worldwide agribusiness. From this perspective, this study carried out a bibliographic investigation regarding the advances in genetic improvement aimed at drought stress in crops using a hybrid model of analysis of scientific articles. The analysis employed bibliometric parameters for qualitative and quantitative discussion of scientific production and the methodological process of systematic review for the synthesis of the results obtained. The work was divided into four stages: the search for articles in databases, meta-analysis, bibliometric analysis, and systematic analysis. Scientific articles were searched for on the Scopus, Scielo, and Web of Science databases within a 20-year timeframe. Most authors and institutions were from Asian countries, demonstrating the need for global expansion of research on the subject. With regard to the co-occurrence networks between the keywords used in the search, a focus was observed on the following terms: drought resistance, drought stress; drought, and drought tolerance. Evidently, the primary mechanism of tolerance or even resistance studied in breeding programs is associated with the expression of genes and genetically modified organisms that confer resistance to plants. Also, the crops addressed in the research retrieved are highly diverse.

Soil compaction is a recurring problem in agriculture that ultimately leads to a reduction in crop productivity. However, the application of agro-industrial residues from the burning of plant biomass can improve the chemical and physical properties of soil. The objective of this study was to evaluate the growth of Paiaguás grass under different soil densities and wood ash doses. The experiment was carried out in a randomized block design, under a 5 × 5 factorial scheme, with five soil compaction values (1.0, 1.2, 1.4, 1.6, and 1.8 Mg m-3) and five doses of wood ash (0, 8, 16, 24, and 32 g dm-3), with four replicates. A soil density greater than 1.2 Mg m-3 reduced the dry mass of Paiaguás grass. The wood ash dose of 20.42 g dm-3 led to the highest shoot dry mass. Root growth was highest at a wood ash dose of 16.52 g dm-3.

Potassium and nitrogen are essential nutrients and their uptake and distribution within plants must be coordinated for optimum growth and development. We evaluated the interaction between nitrogen and potassium fertilization on the development of BRS 394 wheat, and the nitrate and ammonium levels in Oxisol soils. A 5² factorial design was used in a greenhouse experiment, with four replicates in randomized blocks, corresponding to five doses of nitrogen (0, 70, 140, 210, and 280 mg dm^-3) and five doses of potassium (0, 50, 100, 150, and 200 mg dm^-3). The variables analyzed were shoot dry mass; chlorophyll index; nitrate reductase; nitrogen, potassium, and protein concentrations in the leaves; and nitrate and ammonium levels in the soil. There was an interaction between nitrogen and potassium doses on the chlorophyll index, with nitrogen doses between 152.67 and 163.53 mg dm^-3 and potassium of 191.50 mg dm^-3 providing the highest chlorophyll index. The other variables were influenced separately by the nitrogen dose. The highest nitrate reductase enzyme activity was 1.30 µmol NO h^-1 g^-1 Fresh Matter, which was reached at a nitrogen dose of 95 mg dm^-3. Shoot dry mass, concentrations of nitrogen and total protein in the leaves, and concentrations of nitrate and ammonium in the soil were adjusted to the linear regression model as a function of nitrogen fertilization. The dose of nitrogen that promoted the best development of BRS 394 wheat and the highest concentrations of nitrate and ammonium in Oxysol soils was 280 mg dm^-3.

The use of agro-industrial waste, such as wood ash or biomass ash, has been adopted as an alternative to synthetic fertilizers for providing nutrients to plants. This study aimed to evaluate the levels of primary and secondary macronutrients in soil cultivated with chrysanthemum under different types of fertilization management: organic, organomineral, and mineral, with and without liming. The experiment was conducted in a greenhouse for 185 days, using a randomized blocks design in a 5 × 2 factorial scheme: five fertilization types (incubated and unincubated wood ash, organomineral fertilizer, mineral fertilizer, and control) and two levels of liming (without liming and 70% base saturation) with five replicates. The soil used was Oxisol. The phosphorus, potassium, calcium, magnesium, and sulfur contents in the soil after cultivation were analyzed. There was a 77% increase in potassium in treatments with ash compared to treatments without ash. The corrected soil presented 173.2 mg dm⁻³ of potassium, compared to 153.6 mg dm⁻³ in the uncorrected soil, an increase of 11.6%. The calcium levels increased by 60% with the application of ash (incubated or not) and organomineral fertilizer, compared to soils without ash. Liming increased calcium by 1.12 cmol_c dm⁻³. Fertilizers with ash associated with liming resulted in higher magnesium levels. The sulfur content varied according to the fertilizer, with non-incubated ash showing the highest value (69.11 mg dm⁻³) compared to the control (11.08 mg dm⁻³), a difference of 83.96%. Organomineral fertilizer is an alternative for increasing the availability of macronutrients in the soil, allowing a second cropping cycle without the need to manage soil fertility, contributing to sustainable agriculture, encouraging the reuse of waste, and reducing the use of mineral fertilizers.