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Currently, high doses of vinasse are employed for the fertigation of sugarcane with positive results on yield. Usually, this effect is related to the presence of mineral nutrients in its composition as well as to its action on soil properties. Consequently, the concentrations of minerals, organic acids, and other metabolites in vinasse are very well characterized. However, considering that cane vinasses are obtained from the treatment of vegetal tissues, it is also possible that they might contain significant concentrations of phytoregulators that could have a relevant role in their beneficial action on yield. To investigate this hypothesis, we analyzed the main plant hormones in 22 samples of vinasse collected in different production sites of Brazil using HPLC–mass spectrometry. The results show that both ABA and IAA present concentrations in vinasse within the micromolar range, thus being potential active ingredients affecting plant development. In conclusion, the beneficial action of cane vinasses on sugarcane yield might involve, among other factors, the action of IAA and ABA on plant growth. [ABSTRACT FROM AUTHOR]

The microbial composition of the rhizosphere and greenhouse gas (GHG) emissions under the most common input combinations in maize (Zea mays L.) cultivated in Brazil have not been characterized yet. In this study, we evaluated the influence of maize stover coverage (S), urea-topdressing fertilization (F), and the microbial inoculant Azospirillum brasilense (I) on soil GHG emissions and rhizosphere microbial communities during maize development. We conducted a greenhouse experiment and measured methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) fluxes from soil cultivated with maize plants under factorial combinations of the inputs and a control treatment (F, I, S, FI, FS, IS, FIS, and control). Plant biomass was evaluated, and rhizosphere soil samples were collected at V5 and V15 stages and DNA was extracted. The abundance of functional genes (mcrA , pmoA , nifH , and nosZ) was determined by quantitative PCR (qPCR) and the structure of the microbial community was assessed through 16S rRNA amplicon sequencing. Our results corroborate with previous studies which used fewer input combinations and revealed different responses for the following three inputs: F increased N2O emissions around 1 week after application; I tended to reduce CH4 and CO2 emissions, acting as a plant growth stimulator through phytohormones; S showed an increment for CO2 emissions by increasing carbon-use efficiency. IS and FIS treatments presented significant gains in biomass that could be related to Actinobacteria (19.0%) and Bacilli (10.0%) in IS, and Bacilli (9.7%) in FIS, which are the microbial taxa commonly associated with lignocellulose degradation. Comparing all factors, the IS (inoculant + maize stover) treatment was considered the best option for plant biomass production and GHG mitigation since FIS provides small gains toward the management effort of F application. [ABSTRACT FROM AUTHOR]

Background and Aims Chrysolaena obovata, an Asteraceae of the Brazilian Cerrado, presents seasonal growth, marked by senescence of aerial organs in winter and subsequent regrowth at the end of this season. The underground reserve organs, the rhizophores, accumulate inulin-type fructans, which are known to confer tolerance to drought and low temperature. Fructans and fructan-metabolizing enzymes show a characteristic spatial and temporal distribution in the rhizophores during the developmental cycle. Previous studies have shown correlations between abscisic acid (ABA) or indole acetic acid (IAA), fructans, dormancy and tolerance to drought and cold, but the signalling mechanism for the beginning of dormancy and sprouting in this species is still unknown. Methods Adult plants were sampled from the field across phenological phases including dormancy, sprouting and vegetative growth. Endogenous concentrations of ABA and IAA were determined by GC-MS-SIM (gas chromatography-mass spectrometry-selected ion monitoring), and measurements were made of fructan content and composition, and enzyme activities. The relative expression of corresponding genes during dormancy and sprouting were also determined. Key Results Plants showed a high fructan 1-exohydrolase (EC 3.2.1.153) activity and expression during sprouting in proximal segments of the rhizophores, indicating mobilization of fructan reserves, when ABA concentrations were relatively low and precipitation and temperature were at their minimum values. Concomitantly, higher IAA concentrations were consistent with the role of this regulator in promoting cell elongation and plant growth. With high rates of precipitation and high temperatures in summer, the fructan-synthesizing enzyme sucrose:sucrose 1-fructosyltransferase (EC 2.4.1.99) showed higher activity and expression in distal segments of the rhizophores, which decreased over the course of the vegetative stage when ABA concentrations were higher, possibly signalling the entry into dormancy. Conclusions The results show that fructan metabolism correlates well with endogenous hormone concentrations and environmental changes, suggesting that the co-ordinated action of carbohydrate metabolism and hormone synthesis enables C. obovata to survive unfavourable field conditions. Endogenous hormone concentrations seem to be related to regulation of fructan metabolism and to the transition between phenophases, signalling for energy storage, reserve mobilization and accumulation of oligosaccharides as osmolytes. [ABSTRACT FROM AUTHOR]

Endogenous cytokinins, auxins, and abscisic acid (ABA) were identified and quantified in 11 red algae collected from the Brazilian coast. Field materials and two isolates cultured in the laboratory were extracted with various solvents and buffers containing a mixture of appropriate internal standards, purified by solid-phase extraction followed by immunoaffinity chromatography, and analyzed by liquid chromatography-tandem mass spectrometry. Isoprenoid cytokinins (free and conjugated forms of isopentenyladenine [iP], cis-zeatin [ cZ], and trans-zeatin [ tZ]) were detected in all species with concentrations of cZ and iP forms being higher than tZ forms. Dihydrozeatin (DHZ) and its metabolites were only detected at very low levels in nine of the studied species. Aromatic cytokinins (6-benzylaminopurine [BA], ortho- and meta-topolin [ oT and mT]) were not detected in any of the samples. The cytokinin profile of Chondracanthus teedei (Mert. ex Roth) Kütz. was distinct in comparison to other species with para-topolin ( pT) derivatives detected in low concentrations. The main auxins present in all species were free indole-3-acetic acid (IAA) and indole-3-acetamide (IAM). Indole-3-ethanol (IEt), indole-3-acetyl glutamic acid (IAGlu), and indole-3-acetyl leucine (IALeu) were detected in a few species at low concentrations. ABA was present in all species analyzed except for Hypnea nigrescens Grev. ex J. Agardh. No ABA conjugates were detected in any species. These results confirm that cytokinins, auxins, and ABA were common constituents in red seaweeds, with this being the first report of the occurrence of ABA in Rhodophyta. The complexity of the hormone profiles suggests that plant hormones play a role in regulating physiological processes in Rhodophyta. [ABSTRACT FROM AUTHOR]

Seaweed extracts have several functions in agriculture due to their composition that is rich in nutrients, plant hormones, and bioactive substances. It is a natural product used as a biostimulant especially to promote the growth and development of plants and their tolerance to environmental stresses. The objective of this study was to analyze the response to a biostimulant containing seaweed extract derived from Ascophyllum nodosum in the cultivation of tomato and eggplant seedlings, analyzing the growth and physiological parameters in two different regions of Brazil. Cherry tomato and eggplant were cultivated in polyethylene trays for 30 days. In each crop, five treatments were tested, comparing the use of a commercial seaweed extract in application doses and forms, which were the control (without seaweed application); 0.1%, 0.2%, and 0.3% of the seaweed extract applied by irrigation water; and treatment with 0.2% of the seaweed extract by foliar application. This study confirms the efficacy of incorporating seaweed extract from Ascophyllum nodosum as a bio-input into the production phase of Solanaceae seedlings. The seedlings which received the seaweed extract significantly increased some morphological parameters, mainly regarding the biomass and length of leaves, stems, and roots. In general, applying both methods through irrigation water and foliar application were effective in providing benefits compared to the control treatment. The intermediate dose (0.2%) was the most effective in promoting improvement in the analyzed parameters. This underscores the importance of obtaining quality seedlings for subsequent planting in the field, potentially leading to better acclimatization and initial adaptation. [ABSTRACT FROM AUTHOR]

The presence of sexual hormones (female estrogens) was assessed in sediments of a mangrove located in the urban region of southern Brazil. The estrogens are involved in human sexual reproduction. They act as the chemical messengers, and they are classified as natural and synthetic. The estrogens inputs in the environment are from treated and untreated sewage. The presence of estrogens in sewage is excretion from the female due to natural production and use of contraceptives (synthetic estrogens). With the indiscriminate release of sewage into the environment, estrogens can be found in rivers, lakes, and even in oceans. In this work, the presence of estrone (E1), 17-β-estradiol (E2), and 17-α-ethynilestradiol (EE2) in eight sedimentary stations in Itacorubi mangrove located on Santa Catarina Island, south Brazil, was investigated. Historically, the Itacorubi mangrove has been impacted by anthropogenic activities because the mangrove is inserted in the urban area of the Florianopolis. The estrogen EE2, used as contraceptive, had the highest concentration in mangrove sediment, 129.75 ± 3.89 ng/g. E2 was also found, with its concentration ranging from 0.90 ± 0.03 to 39.77 ± 1.19 ng/g. Following the mechanism, under aerobic or anaerobic conditions, E2 will first be oxidized to E1, which is further oxidized to unknown metabolites and finally to CO and water (mineralized). EE2 is oxidized to unknown metabolites and also finally mineralized. Theoretically, under anaerobic conditions, EE2 can be reduced to E1 even in environments such as mangrove which is essentially anaerobic. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate seed germination and the initial development of soybean plants with low physiological quality seeds submitted to different doses of phytoregulator. The experiment was carried out from March to April 2018 in Campo Novo do Parecis, MT, Brazil. The experimental design was of completely randomized blocks, in a 3x4 factorial scheme, being three soybean cultivars: Monsoy 7739, Desafio and Monsoy 8372, and four doses of phytoregulator: 0.0; 0.5; 0.75 and 1.0 L ha-1 of Stimulate® composed of cytokinin, indole butyl acid and giberelic acid. Totaling 12 treatments with four replicates. The evaluated variables were: initial germination, final germination, plant height, dry shoot mass, dry root mass and total dry mass. The cultivars responded differently to the phytoregulator doses. The cultivar Monsoy 7739 responded positively to the use of phytoregulator, as it increased germination, presented higher plant height, dry root mass and total dry mass, at the maximum dose of 1.0 L ha-1 .The cultivar Desafio responded negatively to the phytoregulator, as germination presented significant differences compared the other evaluated variables. Monsoy 8372 did not conclusively respond to the use of the phytoregulator conclusively. [ABSTRACT FROM AUTHOR]

Blueberry production is increasing in Brazil, and growers are turning to bio-inputs or biostimulants to be used on their growth. This has been due to the growing concern about sustainability in the food production chain and the necessity to increase the yield. The current experiment aimed at evaluating the effects of Samurai King, EM-1 and Brutal Plus (Minhofértil) biostimulants on the cultivation of Southern Highbush blueberries (V. corymbosum L.), cultivar 'Biloxi'. The parameters evaluated were plant height (cm), diameter of the main stem (mm), number of shoots, chlorophyll content, total number of leaves, leaf length and width. The total mass, number of fruits, average mass per fruit, the transversal and longitudinal diameters, and the total sugars (°Brix) were also measured. In 2020, the treatment of Samurai King + EM-1 showed the highest efficiency for the studied parameters related to fruits and yield but with no significant difference as compared to the other treatments. Regarding the plant growth, treatments 1 (Brutal Plus) and 5 (Brutal Plus + EM-1) were the most efficient. In 2021, treatment 7 (Brutal Plus + Samurai King + EM-1) had the highest yields, except for average mass per fruit and total sugars. In the two years of evaluation, although treatments obtained lower averages than the control, the effect observed was generally positive, revealing the efficiency of products containing microorganisms for the growth of blueberry plants. In conclusion, these bioproducts could remarkably affect plant biomass, production and fruit quality, resulting in better yields. [ABSTRACT FROM AUTHOR]

The use of plant-based and micro-organism-based biological inputs is a sustainable agricultural practice. It promotes a suitable and better utilization of non-renewable resources in the environment. The benefits of using micro-organisms are associated with direct and indirect mechanisms, mainly related to improvements in the absorption and availability of nutrients, resulting in a consequent impact on plant growth. The main benefits of using biochemical pesticides are the promotion of sustainability and the management of resistance to pests and diseases. Although the use of micro-organisms and botanical metabolites is a promising agricultural alternative, they are still primarily concentrated in grain crops. There is a huge opportunity to expand the plant-based and micro-organism-based biological inputs used in agriculture due to the wide range of mechanisms of action of those products. At a global level, several terminologies have been adopted to characterize biological inputs, but many terms used conflict with Brazilian legislation. This review will clarify the classes of biological inputs existing in Brazil as well as present the application and evolution of the market for microbiological and plant-based inputs. [ABSTRACT FROM AUTHOR]

The action of silicon as a salt stress mitigator has been investigated in isolation, and its combined efficacy with other salt stress mitigators needs to be addressed. This work verified whether silicon, in combination with organic matter and Trichoderma harzianum, enhances the production of forage sorghum under saline irrigation and its effects on soil properties. The field experiment was conducted in Parnamirim (PE), a semiarid region of Brazil. Forage sorghum (Sorghum sudanense (Piper) Stapf) was irrigated with saline water (3.12 dS m−1) and subjected to the application of non-silicon, silicon alone, and silicon combined with Trichoderma and organic matter over three consecutive cuts (every three months after germination). Silicon applied in combination significantly increased the content of nutrient ions K+, P, Ca2+, and Mg2+ in sorghum leaves, stems, and panicles and increased P content in the soil by 170, 288, and 92% for the first, second, and third cuts, respectively. When silicon was applied in combination, sorghum's dry and fresh matter (total yield for the three cuts) increased to 62.53 and 182.43 t ha−1, respectively. In summary, applying silicon (Si) combined with Trichoderma and organic matter promotes higher nutrient ion contents in soil and sorghum plants and a higher forage sorghum yield. [ABSTRACT FROM AUTHOR]

Cassava (Manihot esculenta Crantz) is a vital crop for food and economic security in many regions of the world. Despite the economic and social importance of cassava, challenges persist in developing superior varieties that meet the needs of farmers in terms of agronomic performance, nutritional quality, and resistance to pests and diseases. One of the main obstacles for genetic improvement is the lack of synchronization in flowering and the abortion of young flowers, making planned crosses and progeny production difficult. Therefore, the aim of this study was to evaluate the effect of photoperiod, premature pruning, and growth regulators on cassava flowering under low-altitude conditions in Brazil. Eight cassava clones with contrasting flowering capacity were assessed in Cruz das Almas, Bahia, using two photoperiods (ambient condition and extended photoperiod with red light for 12 hours), premature pruning at the first and second branching levels (with and without pruning), and the application of growth regulators: 0.5 mM 6-benzyladenine (BA) and 4.0 mM silver thiosulfate (STS) (with and without). Plots were assessed weekly for the number of female (NFF) and male (NMF) flowers, height of the first branching (H1B, in cm), number of days to the first branching (ND1B), and the number of branching events up to 240 days after planting (NOB). The extended photoperiod did not promote an increase in the number of flowers but allowed for precocity in cassava flowering, reducing the onset of flowering by up to 35 days, and significantly increasing the number of branches, which is closely related to flowering. The use of pruning and plant growth regulators (PGR) resulted in an increase in NFF from 2.2 (control) to 4.6 and NMF from 8.1 to 21.1 flowers. Therefore, under hot and humid tropical conditions at low altitudes in the Recôncavo of Bahia, manipulating the photoperiod and using premature pruning and plant growth regulators can accelerate cassava flowering, benefiting genetic improvement programs. [ABSTRACT FROM AUTHOR]

Citrus is one of the most important fruit crop of Pakistan in terms of area and production. Pakistan ranks 7th according to area and 13th according to production. While comparing with leading citrus producing nations like Brazil, USA, China and Spain, citrus production of Pakistan is far behind and increasing at an average annual rate of only 5%. Brazil holds the 35% share in total citrus production of world while share of Pakistan is only 1.46%. Citrus cultivars are propagated asexually through grafting and budding on specific rootstocks. Rootstocks play very important role in Citriculture industry and decide success or failure of citrus cultivation. Under a specific and uniform set of climatic and soil conditions, citrus rootstocks tend to vary in their compatibility with a specific scion cultivar. The rootstocks have significant influence overall growth of tree including vegetative growth, mineral uptake, physiological performance of scion cultivar and reproductive growth of scion cultivars. The role of rootstocks in manipulating or improving the performance of citrus scion cultivars has been discussed in present review. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Maize is a crop of significant economic importance. In the northeast region of Brazil, it serves as the foundation of family support for the majority of farmers. However, achieving high levels of productivity requires an adequate water supply throughout its growth cycle. The northeast semi-arid region experiences low rainfall and high potential evapotranspiration, directly affecting maize development and leading to severe declines in productivity. In this study, genetic selection and proteomic analysis are proposed as a strategy to identify the tolerance of maize cultivars against water stress. The experiments were conducted under two water regimes using randomized block designs with three replicates. Development and productivity traits were evaluated, and genetic parameters were estimated using mixed linear models. Selection for water stress tolerance was based on the harmonic mean of the relative performance of genotypic values. Total protein extraction from maize leaves followed the protocol established by the phenol method, and peptides were analyzed through mass spectrometry. The AG8677P cultivar demonstrated remarkable productivity under drought stress conditions, and proteins related to various fundamentally important biological processes for the tolerance mechanism were identified. The combination of genetic selection with proteomic analysis proves to be an efficient strategy, even in the face of limited resources and a small number of treatments. [ABSTRACT FROM AUTHOR]

Flower induction and differentiation are complex phenomenon not fully understood in pear trees. Paclobutrazol (Pbz), Ethephon (Eth), and naphthaleneacetic acid (NAA) exogenous applications could be potential tools to increase return bloom and yield, and to manage the alternate bearing in some pear cultivars. The objective of this research was to evaluate the effect of Eth, Pbz, and NAA on return bloom and yield of 'Rocha' pear trees in different climatic conditions of Southern Brazil. The experiments were performed during 2015/2016–2017/2018 growing seasons, in São Joaquim, Santa Catarina State, and during 2015/2016–2016/2017 growing seasons in Antônio Prado, Rio Grande do Sul State. The pear 'Rocha' were grafted on quince rootstock 'BA29' (experiment 1 and 3) and Pyrus calleryana (experiment 2). Treatments consisted of Eth, Pbz, NAA, and Eth + NAA sprayed at different concentrations and timings. Shoot length, pruning weight, fruit set, number of thinned fruit and total fruit per tree, yield, average fruit weight, flesh firmness, and soluble solids content were assessed. Shoot length decreased, whereas return bloom and yield components increased when using Eth, Pbz, and Eth + NAA in all experiments. However, the positive effect is only in the rate of 10 mg L–1 NAA in experiment 1. Fruit size was reduced in Eth concentrations above 300 mg L–1, as a direct effect of crop load. Our results show that Eth and Pbz increase return bloom and yield of 'Rocha' pear trees being a potential tool to improve flowering in warm winter Regions as Southern Brazil. [ABSTRACT FROM AUTHOR]

Moniliasis caused by the fungus Moniliophthora roreri is one of the most destructive cacao diseases in tropical America. In 2021, the presence of the pathogen was confirmed in cacao plantations in Brazil. This is the first proteomic study of the M. roreri protein profile of ungerminated spores and mycelium compared by 2D SDS‐PAGE (Two‐dimensional gel electrophoresis) associated with mass spectrometry. A total of 446 spots were detected on ungerminated spores gels and 402 spots on M. roreri mycelial gels. A total of 29 proteins were identified from the ungerminated spores, 21 of them were exclusive, and 53 were identified in the mycelium, 16 of them were exclusive. Most of the identified proteins at both development stages were categorized as being involved in metabolic processes, reduction/oxidation processes, and protein synthesis and folding. The interaction networks observed expand the known interactions of these proteins, resulting in eight functional clusters for proteins identified in ungerminated spores and seven clusters for mycelial proteins. In addition, a biological model of ungerminated spores and mycelium with cell location of proteins was constructed. The results contribute to a better understanding of the metabolic mechanisms of M. roreri during dormancy and vegetative development, which can support future studies for strategies to control moniliasis. [ABSTRACT FROM AUTHOR]

Brazil stands out as the largest producer of sour passion fruit; however, the water available for irrigation is mostly saline, which can limit its cultivation. This study was carried out with the objective of evaluating the effects of salicylic acid in the induction of tolerance in sour passion fruit to salt stress. The assay was conducted in a protected environment, using a completely randomized design in a split-plot scheme, with the levels of electrical conductivity of the irrigation water (0.8, 1.6, 2.4, 3.2, and 4.0 dS m−1) considering the plots and concentrations of salicylic acid (0, 1.2, 2.4, and 3.6 mM) the subplots, with three replications. The physiological indices, production components, and postharvest quality of sour passion fruit were negatively affected by the increase in the electrical conductivity of irrigation water, and the effects of salt stress were intensified in the second cycle. In the first cycle, the foliar application of salicylic acid at concentrations between 1.0 and 1.4 mM partially reduced the harmful effects of salt stress on the relative water content of leaves, electrolyte leakage, gas exchange, and synthesis of photosynthetic pigments, in addition to promoting an increase in the yield and quality parameters of sour passion fruit. [ABSTRACT FROM AUTHOR]

Plant growth-promoting substances have been commercialized in agriculture, especially synthetic hormones such as kinetin (KIN), gibberellic acid (GA3), and indole-3-butyric acid (IBA). However, few studies proved the agronomic effect of these substances on the main crops. The objective of this work was to evaluate rates and methods of application of a hormonal plant growth promoter (HPGP −0.09 g L−1 KIN, 0.05 g L−1 GA3, and 0.05 g L−1 IBA) and their effects on wheat grain yield and nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) uptake. The research was carried out in Londrina, Brazil. A randomized block design was implemented, considering a 2 × 3 × 4 factorial arrangement. It was composed of two genotypes (BRS Gralha–Azul and BRS Sanhaço), three HPGP rates (0, 5, and 10 mL kg−1) applied on the seeds, and four HPGP rates (0, 0.25, 0.5, and 1 L ha−1) sprayed on the leaves. Applications of HPGP did not change grain yield, density of fertile plants, lodging, plant height, aboveground dry matter (AGDM); P, Ca, and Mg concentration in the AGDM; and P, K, Ca, and Mg utilization efficiency (UE). In 2016, the application of 5 mL kg−1 HPGP on the seeds (without HPGP on the leaves) increased by 20.9% the N concentration in the AGDM. In 2017, NUE increased up to 21.2% in response to HPGP sprayed on the leaves. The diversity of interactions among genotypes, HPGP application techniques, and weather conditions hinders the assertive use of the product by farmers. [ABSTRACT FROM AUTHOR]

Sappan wood is a useful woody plant from Brazil that could possibly be utilized as a natural dye. The generative proliferation of Sappan wood is hindered by its sluggish seed germination (dormancy), which necessitates greater efforts to break seed dormancy through the use of plant growth regulator (PGR) and organic matter as a planting media mixture to improve seedling growth. This study was conducted during dry season from June to September 2022 at experimental field of Faculty of Agriculture, Universitas Padjadjaran_with an aim to determine the effect of PGR (IAA, NAA, BAP) and organic matter (cow manure) on the growth of Sappan wood seeds. The design used was a randomized block design (RBD) with 14 combination treatments of different types of PGR with the concentration of 1.25 ppm and the use of organic matter that is cow manure (comparison 2:1) with three replications. The data obtained were then processed using one-way ANOVA and continued with the Duncan Multiple Range Test (DMRT) at a 95% confidence level. The use of plant growth regulators (auxin and cytokinin) and organic matter affected the growth of Sappan wood seedlings, especially on the variables of seedling height (22.37 cm), stem diameter (3.89 mm), number of leaves (8.67), leaf area (104.84 cm²), root length (26.03 cm), dry weight of roots (1.15 g) and dry weight of the stem (1.6 g), but it was not significantly affected by the root volume. The combination of IAA+BAP 1.25 ppm and organic matter in the form of cow manure (2: 1) was selected as the best treatment to increase the growth of Sappan wood seedlings. [ABSTRACT FROM AUTHOR]

Agricultural systems are highly affected by climatic factors such as temperature, rain, humidity, wind, and solar radiation, so the climate and its changes are major risk factors for agricultural activities. A small portion of the agricultural areas of Brazil is irrigated, while the vast majority directly depends on the natural variations of the rains. The increase in temperatures due to climate change will lead to increased water consumption by farmers and a reduction in water availability, putting production capacity at risk. Drought is a limiting environmental factor for plant growth and one of the natural phenomena that most affects agricultural productivity. The response of plants to water stress is complex and involves coordination between gene expression and its integration with hormones. Studies suggest that bacteria have mechanisms to mitigate the effects of water stress and promote more significant growth in these plant species. The underlined mechanism involves root-to-shoot phenotypic changes in growth rate, architecture, hydraulic conductivity, water conservation, plant cell protection, and damage restoration through integrating phytohormones modulation, stress-induced enzymatic apparatus, and metabolites. Thus, this review aims to demonstrate how plant growth-promoting bacteria could mitigate negative responses in plants exposed to water stress and provide examples of technological conversion applied to agroecosystems. [ABSTRACT FROM AUTHOR]

Nitrogen (N) is one of the promising nutrients for lawn growth and is required for the lawn's proper growth and development, but it also increases mowing frequency. Glyphosate herbicide application in sub-doses, as a growth regulator, can reduce the maintenance costs without any adverse reduction in the density and nutritional status of grasses. The objective of this study was to evaluate the influences of nitrogen and glyphosate doses on the growth, aesthetic quality and nutritional status of emerald grass (Zoysia japonica Steud.). The experiment was conducted at the Research and Extension Education Farm of São Paulo State University (UNESP), Ilha Solteira, SP, Brazil, in an Ultisol. The experiment was designed as a randomized block with 12 treatments arranged in a 3 × 4 factorial scheme with 4 replications, comprised of a control (without N), 15 and 30 g N m−2 of urea, applied in five splits annually, and glyphosate doses (0, 200, 400 and 600 g ha−1 of the active ingredient, a.i.). The split N fertilization at the rate of 15 g m−2 and glyphosate at the dose of 400 g ha−1 maintained nutritional status of emerald grass. Nitrogen at the rate 15 g N m−2 (in five splits per year) was observed to produce lower growth traits, an adequate aesthetic quality and longer stability of the nutrients in emerald grasses through lower exportation, with removal of "clipping" after mowing. In addition, glyphosate, at the dose of 400 g a.i. ha−1, was efficient in reducing the leaf area, plant height, shoot dry matter and total dry matter by 18.3, 14.7, 6.8 and 8.1%, respectively, as compared to the control. However, this dose did not impair the coloration and resulted in a lower exportation of nutrients by reducing the need to replenish by fertilization. Therefore, fertilization with 15 g N m−2, associated with application of 400 g a.i. ha−1 of glyphosate, is recommended for emerald grass in the tropical savannah of Brazil. [ABSTRACT FROM AUTHOR]

Flooding is a frequent environmental stress that reduces soybean (Glycine max) growth and grain yield in many producing areas in the world, such as, e.g., in the United States, Southeast Asia and Southern Brazil. In these regions, soybean is frequently cultivated in lowland areas by rotating with rice (Oryza sativa), which provides numerous technical, economic and environmental benefits. Given these realities, this work aimed to characterize physiological responses, identify genes differentially expressed under flooding stress in Brazilian soybean genotypes with contrasting flooding tolerance, and select SNPs with potential use for marker-assisted selection. Soybean cultivars TECIRGA 6070 (flooding tolerant) and FUNDACEP 62 (flooding sensitive) were grown up to the V6 growth stage and then flooding stress was imposed. Total RNA was extracted from leaves 24 h after the stress was imposed and sequenced. In total, 421 induced and 291 repressed genes were identified in both genotypes. TECIRGA 6070 presented 284 and 460 genes up- and down-regulated, respectively, under flooding conditions. Of those, 100 and 148 genes were exclusively up- and down-regulated, respectively, in the tolerant genotype. Based on the RNA sequencing data, SNPs in differentially expressed genes in response to flooding stress were identified. Finally, 38 SNPs, located in genes with functional annotation for response to abiotic stresses, were found in TECIRGA 6070 and absent in FUNDACEP 62. To validate them, 22 SNPs were selected for designing KASP assays that were used to genotype a panel of 11 contrasting genotypes with known phenotypes. In addition, the phenotypic and grain yield impacts were analyzed in four field experiments using a panel of 166 Brazilian soybean genotypes. Five SNPs possibly related to flooding tolerance in Brazilian soybean genotypes were identified. The information generated from this research will be useful to develop soybean genotypes adapted to poorly drained soils or areas subject to flooding. [ABSTRACT FROM AUTHOR]

Agave species are widely cultivated crassulacean acid metabolism (CAM) plants for alcoholic beverages, food and fiber production. Among these, the Agave hybrid H11648 ((A. amaniensis × A. angustifolia) × A. amaniensis) is the main cultivar for sisal fiber in the tropical areas of Brazil, China, and African countries. The plants of Agave hybrid H11648 have a long life cycle and large leaves, which require a huge amount of nitrogen nutrient. However, the molecular basis of nitrogen transport and allocation has not been well understood in agave. In this study, we identified 19 NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER FAMILY(NPF) genes (called AhNPFs) with full-length coding sequences in Agave hybrid H11648. Our analysis of gene expression in various types of tissues revealed the tissue-specific expression pattern of AhNPFs. We further examined their expression patterns at different leaf developmental stages, under abiotic/biotic stresses and nutrient deficiency. The results reveal several candidate regulators in the agave NPF family, including AhNPF4.3/5.2/7.1. We first characterized the NPF genes in agave based on published leaf transcriptome datasets and emphasized their potential functions. The study will benefit future studies related to nitrogen nutrient in agave. [ABSTRACT FROM AUTHOR]

Biofortification of cereal crops with zinc and diazotrophic bacteria is a sustainable solution to nutrient deficiency and hidden hunger. The inoculation of staple grain crops such as maize is increased with reducing productivity losses while improving nutrition and use efficiency under climatic extremes and weathered soils of tropical savannah. Therefore, objectives of our study were to evaluate the influence of seed inoculation with diazotrophic bacteria (No inoculation–Control, Azospirillum brasilense, Bacillus subtilis, and Pseudomonas fluorescens) together with residual effect of soil Zn (absence and presence) on growth, yield, Zn nutrition, Zn use efficiencies, and intake of maize in 2019 and 2020 cropping seasons. The inoculation of B. subtilis increased hundred grain mass and yield (14.5 and 17%), while P. fluorescens under residual Zn fertilization has improved shoot and grain Zn concentration in shoot (29.5 and 30.5%). and grain (25.5 and 26.2%), while improving Zn accumulation in shoot (33.8 and 35%) and grain (37.2 and 42%) of maize. The estimated Zn intake in maize was also increased with A. brasilense inoculation and residual Zn application. The Zn use efficiencies including Zn use efficiency, agro-physiological, and utilization efficiency was increased with B. subtilis, while applied Zn recovery was increased with A. brasilense inoculations under residual Zn fertilization. Zinc use efficiency was increased by 93.3 and 397% with inoculation of B. subtilis regardless of Zn application. Therefore, inoculation with B. subtilis and P. fluorescens along residual Zn fertilization is considered the most effective and sustainable strategy for agronomic biofortification of maize under harsh tropical conditions of Brazil. [ABSTRACT FROM AUTHOR]

Drought is one of the most important abiotic stresses responsible for reduced crop yields. Drought stress induces morphological and physiological changes in plants and severely impacts plant metabolism due to cellular oxidative stress, even in C4 crops, such as sugarcane. Seaweed extract-based biostimulants can mitigate negative plant responses caused by drought stress. However, the effects of foliar application of such biostimulants on sugarcane exposed to drought stress, particularly on plant metabolism, stalk and sugar yields, juice purity, and sugarcane technological quality, have received little attention. Accordingly, this study aimed to evaluate the effects of foliar application of a seaweed extract-based biostimulant on late-harvest sugarcane during the driest period of the year. Three experiments were implemented in commercial sugarcane fields in Brazil in the 2018 (site 1), 2019 (site 2), and 2020 (site 3) harvest seasons. The treatments consisted of the application and no application of seaweed extract (SWE) as a foliar biostimulant in June (sites 2 and 3) or July (site 1). The treatments were applied to the fourth ratoon of sugarcane variety RB855536 at site 1 and the fifth and third ratoons of sugarcane variety SP803290 at sites 2 and 3, respectively. SWE was applied at a dose of 500 ml a.i. ha−1 in a water volume of 100 L ha−1. SWE mitigated the negative effects of drought stress and increased stalk yield per hectare by up to 3.08 Mg ha−1. In addition, SWE increased stalk sucrose accumulation, resulting in an increase in sugar yield of 3.4 kg Mg−1 per hectare and higher industrial quality of the raw material. In SWE-treated plants, Trolox-equivalent antioxidant capacity and antioxidant enzyme activity increased, while malondialdehyde (MDA) levels decreased. Leaf analysis showed that SWE application efficiently improved metabolic activity, as evidenced by a decrease in carbohydrate reserve levels in leaves and an increase in total sugars. By positively stabilizing the plant's cellular redox balance, SWE increased biomass production, resulting in an increase in energy generation. Thus, foliar SWE application can alleviate drought stress while enhancing sugarcane development, stalk yield, sugar production, and plant physiological and enzymatic processes. [ABSTRACT FROM AUTHOR]

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Slash pine (Pinus elliottii Engelm.) is an important timber and resin species in the United States, China, Brazil and other countries. Understanding the genetic basis of these traits will accelerate its breeding progress. We carried out a genome-wide association study (GWAS), transcriptome-wide association study (TWAS) and weighted gene co-expression network analysis (WGCNA) for growth, wood quality, and oleoresin traits using 240 unrelated individuals from a Chinese slash pine breeding population. We developed high quality 53,229 single nucleotide polymorphisms (SNPs). Our analysis reveals three main results: (1) the Chinese breeding population can be divided into three genetic groups with a mean inbreeding coefficient of 0.137; (2) 32 SNPs significantly were associated with growth and oleoresin traits, accounting for the phenotypic variance ranging from 12.3% to 21.8% and from 10.6% to 16.7%, respectively; and (3) six genes encoding PeTLP, PeAP2/ERF, PePUP9, PeSLP, PeHSP, and PeOCT1 proteins were identified and validated by quantitative real time polymerase chain reaction for their association with growth and oleoresin traits. These results could be useful for tree breeding and functional studies in advanced slash pine breeding program. Author summary: Slash pine is an important source of original timber and resin production on commercial forest plantations. It is necessary to implement precise breeding strategies to improve timber quality and resin yield. However, little is known about the species' molecular genetic basis. Using a transcriptome dataset with sequencing from 240 individuals in the slash pine population, we combined multiple approaches (based on gene variation, expression variation and co-expression network) to dissect the genetic structure for slash pine major breeding traits. We found that the research population could be divided into three genetic groups with a mean heterozygosity of 0.2246. We also found that six genes with important functions in slash pine resin synthesis and timber formation through association studies. Four new SNPs associatation with the average ring width were also discovered. Our results provide new insights into the molecular genetic basis of important traits in slash pine and provide a comprehensive method for association analyses of conifer tree species with large genome. [ABSTRACT FROM AUTHOR]

Bamboos (Bambusoideae, Poaceae) are multiple-purpose perennial grasses, which display a growing production chain in Brazil. One of the main bottlenecks is high-quality supplying of plantlets, then requiring efficient mass propagation methods, such as micropropagation. Contamination by microorganisms is recurrent in bamboo in vitro cultures, although some of those manifestations are considered endophytes harboring plant growth promotion potential. The isolation of endophytic bacteria from in vitro cultures of Dendrocalamus asper and Bambusa oldhamii was performed to assess their potential growth-promoting effect in co-cultivation with in vitro plants of Guadua chacoensis, an economically promising bamboo species. Among the total bacterial collection (32 isolates), all of them showed growth-promotion potential as indole compounds-producers. Sequences of 16S rRNA genes from eight selected isolates were newly generated, and the BLASTn similarity test recovered four bacterial genera (Bacillus, Brevibacillus, Serratia, and Atlantibacter) and six species. The co-cultivation experiment was carried out with three isolates selected based on their low- (Ba16), medium- (Ba03), and high-yield (Ba24) production of indole compounds, and Bayesian inferences strongly supported them as Bacillus subtilis, Serratia marcescens, and Brevibacillus parabrevis, respectively. The co-cultivation with three bacterial isolates, and their dilution levels, did not influence shoot or root growth and, however, did not cause apparent impairment for G. chacoensis in vitro cultures. Taken together, the isolation of endophytic microorganisms from field-growth bamboo clump and its co-cultivation with in vitro cultures of bamboos is possible, encouraging a continuous discovery and improvement of micropropagation techniques. [ABSTRACT FROM AUTHOR]

Main conclusion: Differences in cell wall components between two BNF-contrasting sugarcane genotypes might result from genetic variations particular to the genotype and from the efficiency in diazotrophic bacteria association. Sugarcane is a plant of the grass family (Poaceae) that is highly cultivated in Brazil, as an important energy resource. Commercial sugarcane genotypes may be successfully associated with beneficial endophytic nitrogen-fixing bacteria, which can influence several plant metabolic pathways, such as cell division and growth, synthesis of hormones, and defense compounds. In this study, we investigated how diazotrophic bacteria associated with sugarcane plants could be involved in the regulation of cell wall formation pathways. A molecular and structural characterization of the cell wall was compared between two genotypes of sugarcane with contrasting rates of Biological Nitrogen Fixation (BNF): SP70-1143 (high BNF) and Chunee (low BNF). Differentially expressed transcripts were identified in transcriptomes generated from SP70-1143 and Chunee. Expression profiles of cellulose and lignin genes, which were more expressed in SP70-1134, and callose genes, which were more expressed in Chunee, were validated by RT-qPCR and microscopic analysis of cell wall components in tissue sections. A similar expression profile in both BNF-contrasting genotypes was observed in naturally colonized plants and in plants inoculated with G. diazotrophicus. Cell walls of the high BNF genotype have a greater cellulose content, which might contribute to increase biomass. In parallel, callose was concentrated in the vascular tissues of the low BNF genotype and could possibly represent a barrier for an efficient bacterial colonization and dissemination in sugarcane tissues. Our data show a correlation between the gene profiles identified in the BNF-contrasting genotypes and a successful association with endophytic diazotrophic bacteria. [ABSTRACT FROM AUTHOR]

The use of Trichoderma fungi in plant production is an interesting biotechnological tool to increase productivity. The research evaluated the potential of two non-commercial strains of Trichoderma asperelloides and T. virens for increasing cabbage yield under field conditions. Growth and productivity parameters were determined at 95 and 150 days after seedling transplantation. The inoculation of the T. asperelloides and T. virens isolates in the soil provided 36.65% and 47.97% increments in the leaf fresh mass values marketed at the first harvest, respectively, thus showing potential for developing crops of Brassica oleracea in the South of Brazil. [ABSTRACT FROM AUTHOR]

Plant growth-promoting bacteria (PGPB) are bacteria that have mechanisms that facilitate plant growth in stress conditions such as drought. The objective of this study was to characterize bacterial strains isolated from bromeliads roots in ironstone outcrops (Urucum Residual Plateau, Mato Grosso do Sul, Brazil) for plant growth-promoting under drought conditions. Firstly, we screened isolates with the presence of 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. Then, all isolates were tested for tolerance to drought, exopolysaccharides (EPS) production, indole-3-acetic acid (IAA)-producing abilities, phosphate and zinc solubilization, production of catalase and hydrolytic enzymes (amylase, cellulase, and protease). Germination assay and a pot experiment with maize plants submitted to well-watered and drought conditions were performed with the strains most promising (VBN11 and VBE23). Briefly, Bacillus cereus VBE23 showed in vitro higher ACC deaminase activity (3.83 and 2.52 µmol α-KB mg−1 h−1 in non-drought and drought conditions, respectively), tolerance to drought, EPS production and other mechanisms of plant growth promotion: solubilization of phosphate and zinc, ammonia production, catalase activity and production of hydrolytic enzymes (amylase, cellulase, and protease). Inoculation of strain VBE23 in maize seeds submitted to drought conditions showed higher germination concerning uninoculated seeds and inoculated with VBN11. Also, the results indicated that the isolate VBE23 provided higher values of fresh and dry biomass compared to the control of uninoculated treatment and inoculated with VBN11 under drought conditions. This is the first report on the PGPB from ironstone outcrops of Urucum Residual Plateau, Mato Grosso do Sul, Brazil. Thus, this bacterial isolate could be used as a strategy for the facilitation of plant growth in drought environments. [ABSTRACT FROM AUTHOR]

Purpose: After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for environmental recovery becomes essential. A greenhouse experiment was carried out to evaluate the biomass production and nutrient accumulation by jack bean (Canavalia ensiformis (L.) DC) and vetiver grass (Chrysopogon zizanioides (L.) Roberty) grown on iron ore tailings from alluvial regions under two edaphic conditions using plant growth regulators. Materials and methods: Iron ore tailings were obtained for use as the substrate. Jack bean and vetiver plants were grown in two conditions, high water and nutrient availability and low water and nutrient availability, while using four doses (0, 0.25, 0.5, and 0.75 L ha−1) of plant growth regulators (kinetins, gibberellic acid, and indole-butyric acid) via leaf spray. Results and discussion: The use of plant growth regulators increased the biomass production (74 and 30% of total dry mass in jack bean and vetiver grass, respectively) and the accumulation of nutrients in the shoot parts of the plants cultivated with greater water and nutritional availability. Under limiting conditions of water and nutritional availability, the jack bean with the highest dose of plant growth regulator had a greater potential for revegetation, biomass production, and inputs of nitrogen, while vetiver grass had a greater contribution in potassium bio-cycling in the areas affected by the tailings deposited in the alluvial regions of the Doce River. Conclusions: The performance of the jack bean stood out in the two edaphic conditions due to growth stimulations by plant growth regulators. [ABSTRACT FROM AUTHOR]

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Seed physiology of wild species has not been studied as deeply as that of domesticated crop species. Trichocline catharinensis (Asteraceae) is an endemic wildflower species from the high‐altitude fields of southern Brazil. This species is of interest as a source of genes to improve cultivated Asteraceae because of its ornamental features, disease resistance and ability to tolerate drought and poor soil conditions. We studied the effects of abscisic acid (ABA) and gibberellic acid (GA3) and their inhibitors, fluridone (FLU) and paclobutrazol (PAC), on seed germination. We individually assessed ultrastructural changes and differential protein accumulation. The principal component analysis explained 69.66% of differential accumulation for 32 proteins at phase II of seed germination in response to hormone and inhibitor treatment. GA3‐imbibed seed germination (98.75%) resulted in increased protein accumulation to meet energy demand, redox regulation, and reserve metabolism activation. FLU‐imbibed seeds showed a higher germination speed index as a consequence of metabolism activation. ABA‐imbibed seeds (58.75%) showed osmotolerance and flattened cells in the hypocotyl‐radicular axis, suggesting that ABA inhibits cell expansion. PAC‐imbibed seeds remained at phase II for 300 h, and germination was suppressed (7.5%) because of the increased signaling proteins and halted reserve mobilization. Therefore, our findings provide insight into the behavior of Asteraceae non‐dormant seed germination, which broadens our knowledge of seed germination in a wild and endemic plant species from a threatened ecosystem. [ABSTRACT FROM AUTHOR]

Bidens subalternans DC. is a weed found in several tropical countries such as Brazil. Large number of produced seeds and easy dispersion favor the colonization of agricultural fields by this species. To know the factors that affect the germination of B. subalternans can help to understand its ecology, permitting to develop control strategies. Laboratory experiments were carried out to evaluate how the temperature, photoperiod, burial depth, water deficit, and salt stress affect the seed germination of B. subalternans. The means of the treatments of each experiment were shown in scatter plots with the bars indicating the least significant difference (LSD, p≤0.05). The results showed a germination percentage above 77% for a wide alternating temperature (15/20 C to 30/35 C night/day). The highest germination and uniformity occurred at 25/30°C night/day. Only 11% of the seeds germinated at a temperature of 35/40°C night/day. The deeper burial of seeds reduced their germination. Only 17% of the seeds germinated in darkness conditions. However, in constant light and 12 hours of light/dark conditions the germination percentage was over 96%, confirming the light dependence of the B. subalternans during germination. In constant light and 12 hours of light/dark, the germination was over 96%. B. subalternans seeds showed sensitivity to water and salt stress, and their germination was inhibited under a water potential of -0.4 MPa and 100.09 mM, respectively. The sensitivity of B. subalternans seeds to high temperatures, water stress, and salt stress explains the high frequency of this weed in south-central Brazil. The light and sowing depth showed that burial of seeds by mechanical control is a strategy to reduce the high infestation of B. subalternans. [ABSTRACT FROM AUTHOR]

The great expansion in recent years in the use of plant biostimulants has underestimated the possibility of producing environmental risks. The objective of this study was to evaluate the cytotoxicity, genotoxicity, and toxicity of three different biostimulants (A, B, and C) produced and widely marketed in Brazil and exported to other countries on both plant and animal indicator organisms. In Allium cepa (non-target species of these plant biostimulants), the concentrations evaluated for the products A and B (0.0625 at 0.500 mL/L), and C (0.0625 at 0.500 g/L) induced inhibition of cell proliferation on meristems, in at least one time of analysis, characterizing them as cytotoxic. The three biostimulants promoted an expressive number of prophases in detriment to the other phases of cell division. In the test with Artemia salina, different concentrations of the biostimulants were tested, ranging from 1000 to 1.95 ppm, and the toxic potential was evaluated through the LC50. The three products showed high toxicity (LC50 < 100 ppm) against microcrustaceans. The results obtained in the present study suggest that the evaluated biostimulants may be toxic to non-target plants and toxic to organisms in water bodies influenced by leaching from soil with the presence of these substances. [ABSTRACT FROM AUTHOR]

An improved understanding of seed quality and germination control can contribute effectively to the use and conservation of neglected native species with ecological and economic value, such as Trichocline catharinensis, an endemic Asteraceae species from southern Brazil. We investigated the effects of applying gibberellin (GA3), abscisic acid (ABA) and their biosynthesis inhibitors, paclobutrazol (PAC) and fluridone (FLU), respectively, on T. catharinensis seed germination, and on polyamine (PA) content and antioxidant enzyme activities in germinating seeds. FLU and GA3 increased seed germination speed compared to treatment with H2O only. ABA inhibited both germination speed index and percentage, while PAC severely inhibited seed germination. The stimulatory effect of GA3 and FLU was associated with increased contents of putrescine (PUT) and spermidine (SPD) relative to spermine (SPM). As a result, high ratio (PUT + SPD/SPM) as well as superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) enzyme activities were observed when seed germination occurs. In contrast, in low or no seed germination treatment (ABA and PAC), low ratio (PUT + SPD/SPM) was observed, while the antioxidant enzymes, mainly SOD activity, tended to increase. Application of PAs at 200 μM stimulated germination through improving the speed and uniformity, and this effect was associated with antioxidant enzyme activity. Our results suggest a relationship between PA and the antioxidant system with the physiological mechanism of seed germination. These results improve the physiological knowledge of seed germination control in Asteraceae and contribute to the biological groundwork for future studies on the use and conservation of native species. [ABSTRACT FROM AUTHOR]

Ineffective management of pastures still constitutes the main problem in the Brazilian livestock industry, in which recovery of soil fertility is a determinant for soil restoration. In this context and in combination with the adoption of sustainable technologies, the use of plant-growth-promoting bacteria (PGPB) may represent an alternative to the use of chemical fertilisers that would reduce costs and environmental impacts. In this study, morphogenetic and structural characteristics were evaluated in three Urochloa (syn. Brachiaria) varieties. Urochloa is a genus that is present in the most degraded pastures in Brazil. The three varieties were inoculated with five PGPB (Azospirillum brasilense Ab-V5 and Ab-V6, Pseudomonas fluorescens CCTB 03 and ET76, and Pantoea ananatis AMG521) and treated with different doses of nitrogen (N) fertiliser (0, 50 and 100 kg N ha-1) in pots filled with sandy soil under greenhouse conditions. In general, for Marandu grass U. brizantha cvv. BRS Paiaguás and Xaraés, the best performances for leaf and stem elongation rates and number of basal tillers were obtained with strains CCTB 03 and AMG521. For U. ruziziensis, the best performance in the duration and rate of renewal of leaves and leaf senescence was observed with strains AMG521, Ab-V5 and Ab-V6. This result indicated the specificity of the effects of bacterial strains on different genotypes of Urochloa. Differences in the interactions between PGPB and N fertilisation were also verified. In U. brizantha, interaction effects were additive, whereas in U. ruziziensis, they were competitive. The results indicate the feasibility of inoculation of Urochloa with elite strains of PGPB that positively affect the production of forage biomass and allow reductions in N fertiliser usage. [ABSTRACT FROM AUTHOR]

Papaya (Carica papaya L.) is one of the leading fruit trees in Brazil, mainly in the Northeast region. However, some regions suffer from water scarcity, making wastewater reuse a viable alternative for crop production. Also, biostimulants may be used to maximize papaya growth and development. Thus, this work aimed to evaluate the use of Acadian® biostimulant in the growth of Formosa papaya seedlings irrigated with different concentrations of fish-farming wastewater. The experiment was block randomized in a 2 x 5 factorial scheme, use and non-use of biostimulant and five concentrations of wastewater (0, 10, 20, 30, and 40%) diluted in potable water, with four replicates. Qualitative data were compared by t-test at 5% probability, and quantitative data were submitted to regression analysis. Results showed that high concentrations of wastewater negatively affect the production of Formosa papaya seedlings. Acadian® negatively influences plant height, number of leaves, and the ratio between shoot and root. However, the seaweed biostimulant positively influenced the chlorophyll content index. [ABSTRACT FROM AUTHOR]

To investigate the deeper coloring mechanism of berry, the 'Benitaka' (Be) grape, ABA treatment on 'Benitaka' (Be (ABA)), and its deeper coloring bud mutation 'Brasil' (Br) grape were compared three weeks post-ABA treatment (11 weeks post-flowering, 200 mg/g ABA). Firstly, the ABA-treated group exhibited a deeper coloring at three weeks post-ABA treatment than the 'Brasil'. Deeper color in 'Brasil' was caused by higher content of peonidin-3-O-monoglucoside, malvidin-3-O-monoglucoside, and malvidin-3-O-coumarylglucoside, while the deeper color in ABA-treated group was mainly caused by higher content of cyanidin-3-O-monoglucoside and peonidin-3-O-monoglucoside. In addition, the results revealed that 'Brasil' showed deeper coloring than 'Benitaka' was probably due to the higher expression of the VvmybA1 and VvmybA1-1 genes, similar with ABA-treated group. Compared with 'Benitaka', the distinction between the ABA-treated group and 'Brasil' was the expression of VvmybA1 gene. The gene expression was delayed in the ABA-treated group until three weeks post treatment. The VvmybA1 gene and transcription factor play an important role in the anthocyanin biosynthesis, and showed the difference in expressions of the VvmybA1 and VvmybA1-1 gene during different period of time probably due to different kind of anthocyanins. Based on these results, a possible mechanism of anthocyanins biosynthesis was established to elaborate the reason for the deeper coloring in ABA-treated 'Benitaka' and 'Brasil' grapes. [ABSTRACT FROM AUTHOR]

Questions: Riverine and associated vegetation communities are periodically affected by floods. However, there have been few quantitative studies on the structural responses of Neotropical tree communities in semi‐arid regions to this perturbance. Here, we ask whether flooding regimes and soil attributes affect tree species diversity, composition, community structure, and soil attributes in Neotropical dry forests. Locations: Southeast Brazil. Methods: We sampled 120 forest plots of 400 m² totaling 4.8 ha across four tributaries of the São Francisco River with plots situated in areas representing three flooding regimes: (a) annually flooded; (b) occasionally flooded; and (c) never subjected to flooding. Using linear mixed‐effects models, we modelled how flooding regime and soil properties (fertility and texture) affect vegetation diversity (species richness), species composition and structural attributes (abundance of individuals, above‐ground biomass [AGB], and a community‐weighted trait average of multistemness [CWMms]) of these forest plots. Results: Species richness in the annually flooded forests was significantly lower than in occasionally flooded or never flooded forests, in agreement with our models, which showed that flooding regime was a significant predictor for this variable. Flooding regime was a significant predictor of CWMms, with plots in annually flooded forest sites having the highest CWMms values. Soil chemical attributes were a significant predictor of AGB across all plots but not between flooding regime categories. Conclusions: In Neotropical dry forests, environmental filters established by flooding can lead to differences among distinct biomes in vegetation structure, diversity patterns as well as system productivity. Conservation strategies for dry forests should therefore take these factors into consideration. Our study also highlights annually flooded dry forest as a significant component of the regional diversity of dry forests deserving of management attention. [ABSTRACT FROM AUTHOR]

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Copyright of Nucleus (16786602) is the property of Fundacao Educacional de Ituverava and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista em Agronegócio e Meio Ambiente is the property of Revista em Agronegocio e Meio Ambiente and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)