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Processes of water retention and movement and the hydraulic conductivity are altered in the rhizosphere. The aim of this study was to investigate the physical-hydric properties of soil aggregates in the rhizosphere of annual ryegrass ( Lolium multiflorum ) cropped in a Kandiudalfic Eutrudox, taking into account aspects related to soil aggregate stability. Soil aggregates from rhizosphere soil (RZS) and soil between plant rows (SBP) were used to determine soil water retention curves (SWRCs) and saturated hydraulic conductivity ( K sat ). In addition, properties related to soil aggregate stability, such as water-dispersible clay, soil organic carbon (SOC), and microbial activity, were also assessed. The higher microbial activity observed in the RZS was facilitated by increased SOC and microbial activity, resulting in improved soil aggregation (less water-dispersible clay). For nearly all measured matric potentials, RZS had a higher water content than SBP. This was attributed to the stability of aggregates, increase in SOC content, and the root exudates, which improved soil water retention. The increase in total porosity in RZS was associated with improved soil aggregation, which prevents deterioration of the soil pore space and results in higher K sat and hydraulic conductivity as a function of the effective relative saturation in RZS compared to SBP.

Soil management systems can directly interfere with crop yield via changes in the soil's physical and hydraulic properties. However, short- to medium-term experiments of conduction do not always demonstrate the modifications of the management systems in these properties. Thus, the aim of this study was to evaluate the physical properties of the soil in a long-term management system and to relate it to the storage and availability of water to plants, verifying its effect on soybean yield. The experiment was conducted in randomized blocks in a split-plot scheme with four replications. Plots were composed by soil management (conventional tillage and no-tillage), and subplots represented three soil depths (0.0-0.1, 0.1-0.2, and 0.2-0.4 m). The soil's physical and hydraulic properties, root development, and soybean yield were evaluated. The no-tillage system not only presented higher bulk density and soil resistance to compaction up to a depth of 0.2 m but also greater root development. This management also did not affect the process of water infiltration in the soil and presented an increase in soybean grain yield by 6.5%. The long-term no-tillage system (33 years) offers less risk of water stress to soybean plants; it contributes to greater grain yield of this crop when compared to the conventional tillage system.

The tomato crop is very sensitive to stress conditions. A water deficit is defined as when precipitation is less than the evapotranspiration (ETc) of the crop in a given period, and in this scenario of climate change, it is identified as responsible for global productivity losses. The use of potential technologies for better irrigation management, such as electromagnetically treated water, remains controversial. Thus, the objective of the present work was to investigate the effects of very low-frequency electromagnetic resonance field treatment on water for tomato crops submitted to different irrigation rates. For this, an experiment was carried out under controlled conditions with different types of water: electromagnetically treated water (WTVLF) and untreated water (UNW), as well as four water replacement rates: 40, 60, 80, and 100% ETc. The electromagnetic treatment of the water was carried out using the commercial equipment AQUA4D ® . The experiment was carried out in pots with five replications per treatment. Lower activity of SOD, POD, CAT, and APX enzymes was observed in plants irrigated with water treated with very low-frequency electromagnetic resonance fields (WTVLF), indicating less oxidative stress caused by water deficit. Water deficit reduced chlorophyll content, but the effects were less harmful with WTVLF water. The water deficit resulted in less accumulation of dry matter and less productivity in a linear relationship. However, plants irrigated with WTVLF showed increments of about 20% in dry matter accumulation and 20% in fruit production concerning plants irrigated with untreated water, independent of the irrigation rates. We can conclude that irrigation with WTVLF can be a solution to reduce the damage caused by water deficits and increase the productivity of tomato crops.

No-tillage cover crops contribute to better soil quality, being able to replace mechanized tillage management. This observation can only be made after several years of adopting conservationist practices and through research on soil-plant relationships. The objective of the research was to verify the relationship between the production components, physiological, root development, and physical-hydric properties of the soil in the yield of soybean grown in succession to different cover crops or with soil chiseling. The experiment was carried out in a randomized block design with four replications, comparing the cultivation of sunn hemp ( Crotalaria juncea ) and millet ( Penninsetum glaucum L.) as cover crops and a treatment with soil chiseling. The evaluations were carried out during soybean ( Glycine max L.) cultivation in the 2019/20 summer crop, that is, after 17 years of experimenting started in 2003. Rotation with sunn hemp increased soybean yield by 6% and 10%, compared with millet rotation and soil chiseling. The species used in crop rotation in a long-term no-tillage system interfere with the physical and water characteristics of the soil, affecting the physiological responses and soybean yield. The rotation with sunn hemp offers greater water stability to the plants and provides greater soybean yield in succession. Future research that better addresses year-to-year variation, architecture, and continuity of pores provided by crop rotation, and evaluations of gas exchange, fluorescence, and activities of stress enzymes in soybean plants may contribute to a better understanding of soil-plant relationships in long-term no-till.

There are few studies about the influence of fruit maturation and post-harvest resting on seed composition, which can be necessary for seedling development and future establishment. Thus, the objective of this study was to evaluate the effect of maturation and post-harvest resting of fruits on the macronutrient and protein content of sweet pepper seeds. The experimental design was a randomized block, with eight treatments, in a 4 × 2 factorial arrangement. The first factor was fruit maturation stages (35, 50, 65 and 80 days after anthesis), and the second, with and without post-harvest resting of the fruits for 7 days. The characteristics evaluated in seeds were the dry weight of one thousand seeds, macronutrient content, and content of albumin, globulin, prolamin and glutelin proteins. There were reductions in K, Ca and Mg content, and an increase in seed content of albumin, globulin and prolamins as a function of the fruit maturation stage. Post-harvest resting of the fruits provided higher Ca content and protein albumin in seeds. The decreasing order of macronutrients and protein content in seeds, independent of fruit maturation and resting stage of the fruits, was N > K > P > Mg > S > Ca, and albumin > globulin ≈ glutelin > prolamine, respectively.

Salicylic acid (SA) is an important plant regulator reported as a mitigator of water deficit in plants, however without a recommendation for use in field conditions. Thus, this research aims to validate the use of SA under field conditions in regions with low water availability. For that, we evaluated CO 2 assimilation ( A ), stomatal conductance ( g s ), transpiration ( E ), water use efficiency ( WUE ), and carboxylation efficiency ( A/Ci ) at 15, 30, and 45 days of continuous stress water deficit, as well as the application of salicylic acid (0.0; 0.5; 1.0; 1.5; 2.0 mM) in tomato plants subjected to continuous water deficit (45 days), in two years (2019 and 2020). The water deficit reduced the A , g s , E and A/Ci , while the foliar application of SA increased these parameters in all evaluated times, resulting in similar or even higher values than in plants without water deficit. Water deficit caused floral abortion in tomato plants, without the application of SA, reducing the number of fruit production. In contrast, plants that received about 1.3 mM of SA increased A and A/Ci and translocated the photo-assimilates, mainly to flowers and fruits, reducing floral abortion and increasing fruit production. Thus, foliar application of SA was efficient in mitigating the deleterious effects of water deficit in tomato plants regarding the gas exchange and fruit production.

It is known that poorly performed fertigation directly impacts on tomato production and biometric components. In addition, consumers are also affected by interrelated characteristics that interfere with the acceptability of the fruit, such as the physicochemical parameters and nutrients in the fruit. Thus, eco-friendly technologies, such as irrigation with ultra-low frequency electromagnetic treated-water, which attenuates the inadequate management of fertigation, are essential to improve marketable fruit yields. Thus, the objective of the present work was to investigate the impact of treated water with very low-frequency electromagnetic resonance fields in physical, chemical and nutritional parameters at different nutrient solution strengths in tomato fruits. In this study, experiments were carried out in randomized blocks and five doses of fertigation were used (1.5; 2.5; 4.0; 5.5; and 7.0 dS m−1), employing two types of water: electromagnetically treated and untreated. It can be seen that the fertigation affected some parameters, mainly the number of fruits with blossom-end rot, fruit size, and weight. Variance analysis (ANOVA) was performed with the subsequent use of the Tukey test. In all statistical tests, a confidence level of 95% was considered. The soluble solids content increased by 28% as a function of the fertigation doses. The electromagnetically treated water reduced the number of fruits with blossom-end rot by 35% (p < 0.05). Overall, electromagnetic water improved the physicochemical quality parameters and the nutritional status of tomato fruits. Thus, this study demonstrated that green technology could leverage tomato fruit production and quality.