Selection of forage grasses for cultivation under water-limited conditions using Manhattan distance and TOPSIS.

Extreme weather events, such as severe droughts, pose a threat to the sustainability of beef cattle by limiting the growth and development of forage plants and reducing the available pasture for animals. Thus, the search for forage species that are more tolerant and adapted to soil water deficit conditions is an important strategy to improve food supply. In this study, we propose utilizing the mathematical concept of the Manhattan distance to assess the variations in the morphological variables of tropical forage grasses under water-limited conditions. This study aimed to select genotypes of tropical forage grasses under different water stress levels (moderate or severe) at this distance and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). Nine varieties from five species were examined. Forage grasses were grown in 12-L pots under three soil irrigation regimes [100% pot capacity-PC (well-irrigated control), 60% PC (moderate drought stress), and 25% PC (severe drought stress)] with four replicates. Drought stress treatments were applied for 25 days during the forage grass tillering and stalk elongation phases. After exposure to drought stress, the growth and morphological traits of forage plants were evaluated. The results show that the use of the Manhattan distance combined with TOPSIS helps in the genotypic selection of more stable tropical forage grass varieties when comparing plants exposed to moderate and severe drought conditions in relation to the nonstressful environment (control). The 'ADR 300', 'Pojuca', 'Marandu', and 'Xaraés' varieties show greater stability when grown in a greenhouse and subjected to water stress environments. The selected forage varieties can be used as parents in plant breeding programs, allowing us to obtain new drought-resistant genotypes.

Cashew gum hydrogel as an alternative to minimize the effect of drought stress on soybean.

The use of hydrogels helpsthe production of plants in drought-stress environments. Thus, this work evaluated using different hydrogels to minimize drought stress in soybean cultivation. The treatments employed two different hydrogels, one already commercialized and the other produced with cashew gum (Anacardium occidentale), five levels (0, 30, 60, 120, and 240 mg pot-1) of the hydrogels, and two levels of drought stress in sandy soil. The growth and yield of soybeans and the levels of macro- and micronutrients in soybeans were evaluated.growth. The use of CG hydrogel promoted 12% increase in protein content in the seeds in the when soybean plants were subjected to drought stress. The levels of 30 mg pot-1, corresponding to 7.5 kg ha-1, improved the 'morphological and productive parametersof the soybeans. The increasing levels of hydrogel promoted the increase in P, K, Ca, Mg, and Fe and reduced S and Cu on an exponential scale. The use of cashew gum hydrogel increased the K and Ca contents in soybean seeds compared to commercial hydrogel.

Magnesium supplementation alleviates drought damage during vegetative stage of soybean plants.

Our working hypothesis was that magnesium (Mg) supplementation modulates plant performance under low water availability and improves drought tolerance in soybean genotypes. Plants of Bônus 8579, M8808 and TMG1180 genotypes were grown under field conditions and subjected to three water stress treatments (control, moderate and severe stress) and three Mg levels [0.9 (low), 1.3 (adequate) and 1.7 cmolc dm-³ (supplementation)]. After 28 days of drought imposition, the growth parameters, osmotic potential, relative water content, leaf succulence, Mg content and photosynthetic pigments were assessed. In general, drought drastically decreased the growth in all genotypes, and the reductions were intensified from moderate to severe stress. Under adequate Mg supply, TMG1180 was the most drought-tolerant genotype among the soybean plants, but Mg supplementation did not improve its tolerance. Conversely, although the M8808 genotype displayed inexpressive responses to drought under adequate Mg, the Mg-supplemented plants were found to have surprisingly better growth performance under stress compared to Bônus 8579 and TMG1180, irrespective of drought regime. The improved growth of high Mg-treated M8808-stressed plants correlated with low osmotic potential and increased relative water content, as well as shoot Mg accumulation, resulting in increased photosynthetic pigments and culminating in the highest drought tolerance. The results clearly indicate that Mg supplementation is a potential tool for alleviating water stress in M8808 soybean plants. Our findings suggest that the enhanced Mg-induced plant acclimation resulted from increased water content in plant tissues and strategic regulation of Mg content and photosynthetic pigments.

Weed-Hoeing Periods in Cowpea Cultivation under Direct and Conventional Systems.

Weed coexistence with an agricultural crop can negatively affect its growth, development, and yield. From this perspective, this study aimed to evaluate weed management strategies and their effect on the agronomic parameters of cowpea cultivation in direct (SPD) and conventional (SPC) planting systems. The experiment was set up in a completely randomized block design with a split-plot arrangement with four replications. The plots received a source of variation referring to the planting systems (direct and conventional planting), and the subplots corresponded to ten weed management strategies (manual hoeing 18 days after planting (DAP); at 36 DAP; at 54 DAP; at 18 and 36 DAP; at 18 and 54 DAP; at 18 and 72 DAP; at 36 and 54 DAP; at 36-72 DAP; at 18, 36, and 54 DAP; and a control with no hoeing). Density and dry mass evaluations of the cowpea plants were performed at harvest (72 DAP) by determining the number of pods per plant, pod length, number of grains per pod, 1000-grain mass, and yield. A total of 28 species distributed in 12 botanical families were identified in the two cultivation systems. The family Poaceae showed the highest frequency, with 25% of the species identified. At the end of the assay, treatment 20 had the highest positive influence and provided significant quantitative gains to the complex of traits related to cowpea production (SPD and hoeing at 18, 36, and 54 DAP). UPGMA cluster analysis and canonical discriminant analysis were performed and allowed a better classification of the evaluated treatments. It was observed that the first two canonical variables explained 90.8% of the total variance contained in the original variables. The use of SPD with weeding at 18, 36, and 54 days after planting provides greater weed control and significant quantitative gains for the complex of characteristics related to cowpea production. The results underscore the importance of choosing the correct cropping system and implementing effective weeding practices to optimize weed control and improve crop performance.

Physicochemical Evaluation of Cushuro (Nostoc sphaericum Vaucher ex Bornet & Flahault) in the Region of Moquegua for Food Purposes.

The cyanobacterium Nostoc sp. contains considerable amounts of protein, iron, and calcium that could mitigate the problems of anemia and malnutrition in humans. However, the nutritional value of the edible species Nostoc sphaericum Vaucher ex Bornet & Flahault, which grows in the Moquegua region, is unknown. Descriptive research was developed, and samples were obtained from the community of Aruntaya, located in the region of Moquegua. Water samples were taken at two different points (spring and reservoir), and samples of the cyanobacteria were taken in the reservoir. The design used was completely randomized, with three repetitions. Sixteen characteristics associated with the water collected at two points were evaluated, and from the nutritional point of view, seven characteristics were evaluated in the collected algae. The physicochemical characteristics were determined using methods established in the Codex Alimentarius. For the morphological characterization at the macroscopic level, it was observed that the seaweed collected was spherical in shape, grayish-green in color, soft to the touch, and palatable. After carrying out the physicochemical and morphological characterization of the collected samples, it was verified that all were of N. sphaericum. When comparing the sixteen characteristics related to water at the two collection sites, highly significant differences (p < 0.01) were observed for most of the variables evaluated. The average data of the characteristics of the algae showed protein values of 28.18 ± 0.33%, carbohydrates of 62.07 ± 0.69%, fat of 0.71 ± 0.02%, fiber of 0.91 ± 0.02%, ash of 7.68 ± 0.10%, and moisture of 0.22 ± 0.01%. Likewise, calcium reported an average value of 377.80 ± 1.43 mg/100 g and iron of 4.76 ± 0.08 mg/100 g. High correlations (positive and negative) were obtained by evaluating seven characteristics associated with the reservoir water where the algae grew in relation to eight nutritional characteristics of the algae. In relation to the nutritional value, the amounts of protein, iron, and calcium exceed the main foods of daily intake. Therefore, it could be considered a nutritious food to combat anemia and malnutrition.

Production of New Biopesticides from Cymbopogon citratus for the Control of Coffee Rust (Hemileia vastatrix) under Laboratory and Field Conditions.

One of the diseases with the greatest economic impact on coffee cultivation worldwide and particularly in Peru is coffee rust (Hemileia vastatrix). The search for sustainable control methods as disease management strategies in coffee cultivation is necessary. The objective of this research was to determine the effectiveness of five biopesticides based on lemon verbena (Cymbopogon citratus) for the control of rust applied in laboratory and field conditions to allow the recovery of coffee (Coffea arabica L. var. typica) in La Convención, Cusco, Peru. Five biopesticides (oil, macerate, infusion, hydrolate and Biol) and four concentrations (0, 15, 20 and 25%) were evaluated. The biopesticides were evaluated under laboratory conditions (light and dark) at different concentrations. The design used was completely randomized in a factorial scheme. The biopesticides were incorporated into the culture medium and inoculated with 400 uredospores of rust, and the germination percentage was evaluated. Under field conditions, the biopesticides at the same concentrations were evaluated for 4 weeks after application. Under these field conditions, the incidence, severity and area under the disease progress curve (AUDPC) of selected plants with a natural degree of infection were evaluated. In the laboratory, the results showed that all biopesticides were effective in reducing the germination of rust uredospores to values <1% of germination in relation to the control, which showed values of 61% and 75% in the light and dark, respectively, independent of the concentration used, with no significant differences between them. In the field, 25% oil promoted the best response with values <1% and 0% incidence and severity, respectively, in the first two weeks after application. The AUDPC for this same treatment showed values of 7 in relation to 1595 of the control. Cymbopogon citratus oil is an excellent biopesticide that can be used to control coffee rust.

First Report on the Genetic Diversity of Populations of Gossypium barbadense L. and Gossypium hirsutun L. in the Amazonian Native Communities, Cusco-Peru.

The genus Gossypium has important ethnobotanical and economic value for Amazonian Native Communities (A.N.C.). However, little research has been undertaken on the distribution and genetic diversity of cotton populations maintained in the Peruvian rainforest. This work aims to present the first report on the genetic diversity of Gossypium spp. populations in the A.N.C. of the province of La Convención, Cusco-Peru. The methodology was based on exploring, collecting, identifying, and characterizing the Gossypium populations present in the A.N.C. Twenty-six descriptors were evaluated (9 quantitative and 17 qualitative), and with this information, distribution, correlation, and principal component (PC) analyses were carried out. As a result, plants of two species [G. barbadense L. (44 samples) and G. hirsutum L. (19 samples)], one variety [G. barbadense var. brasiliensis (75 samples)], and three previously unidentified variations (9 samples) were identified. Altogether, 147 samples were collected. G. barbadense var. brasiliensis, which was always found in association with other economic crops within an altitude range of 338 to 1086 m, was the most predominant (51%), distributed in eleven A.N.C. and always in small plots (up to 2 ha). G. barbadense L. was cultivated between 397 and 1137 m of altitude in eight A.N.C. in plots of up to 3 ha in marginal lands. G. hirsutum L., with a smaller distribution (13%), was found between 334 and 497 m of altitude in only three communities; this species is cultivated in marginal areas throughout the year. The variability found for the first two PCs when considering the quantitative and qualitative descriptors was high (74.7%) and moderate (48.2%), respectively. When combining all the descriptors, the analysis showed that the first two PCs accounted for 51.8% of the total variability of the data. The PCs of the two types of data and their combination confirmed that the three populations found were grouped. The nine undefined samples were close to or intermediate between the described ones, showing that these samples may be the result of spontaneous crosses; as such, these samples need to be better evaluated with other tools for further definition. The information obtained shows that in the A.N.C. of Cusco-Peru, there is variability conserved by the inhabitants, who have been able to maintain and use these genotypes, even from their Amazonian indigenous ancestry, and the environment has been able to generate variability among the species, as will be highlighted in future works.

Magnetically Treated Water in Phaseolus vulgaris L.: An Alternative to Develop Organic Farming in Cuba.

Phaseolus vulgaris L. (common bean) significantly contributes to the human diet due to its protein, vitamin and mineral contents, making it one of the major edible plant species worldwide. Currently, the genetic resources conserved in germplasm banks in Cuba have experienced a loss of viability, which makes their propagation difficult. Magnetically treated water has been used to improve the response of seeds and plants of different species. However, there is little experimental evidence on the cultivation of the common bean irrigated with magnetically treated water or its positive effects on seed germination recovery and its effects on physiological, anatomical and morphological characteristics. This study aims to evaluate the growth and development of common bean with magnetically treated water as an alternative to rejuvenate the seeds for organic agriculture. A two-group experimental design was used: a group of plants irrigated with water without a magnetic field and a group of plants irrigated with water treated with a magnetic field at induction in the range of 100 to 150 mT. There was an increase of 25% in the percentage of germination; the stomatal anatomical structures behaved normally; and the stem length, vigor index, leaf area and seed weight increased by 35, 100, 109 and 16%, respectively. The concentrations of chlorophyll a, chlorophyll b pigments and carbohydrates in the plants grown with magnetically treated water were also stimulated in relation to control plants with increments of 13, 21 and 26%, respectively. The technology employed in this study did not have negative effects on the plant nor did it affect the presence of structures or the net content of the assessed compounds. Its use in the cultivation of Phaseolus vulgaris L. might represent a viable alternative for the improvement of the plant in organic farming production.

Synthesis of Aza-BODIPYs, Their Differential Binding for Cu(II), and Results of Bioimaging as Fluorescent Dyes of Langerhans ß-Cells.

Cellular labeling through the use of dyes is of great interest to the biomedical sciences for the characterization of the location and distribution of biomolecules and also for the tracking of the course of biological processes in both health and illness. This paper reports the synthesis, characterization, and subsequent evaluation as metal sensors and cell staining probes of four aza-BODIPY compounds [herein referred to as 7(a-d)]. Compounds 7(b-d) were found to display an outstanding selectivity for Cu(II) because their emission band at 720 nm was progressively quenched by this metal, presenting fluorescence quenching between 75 and 95%. On the other hand, cell imaging studies with pancreatic ß-cells proved that aza-BODIPYs 7a and 7b showed selectivity for the cytoplasm, while 7c and 7d were selective for the cell membrane. Moreover, aza-BODIPY 7b allowed to characterize in a clear way a lipotoxic condition mediated by saturated fatty acids, a critical phenomenon on ß-cell damage associated with diabetes mellitus type II. Taken together, the presented results highlight the obtained aza-BODIPY compounds as selective sensing/staining probes with the potential to be used in the biomedical field.

Selection of Soybean Genotypes under Drought and Saline Stress Conditions Using Manhattan Distance and TOPSIS.

The search for soybean genotypes more adapted to abiotic stress conditions is essential to boost the development and yield of the crop in Brazil and worldwide. In this research, we propose a new approach using the concept of distance (or similarity) in a vector space that can quantify changes in the morphological traits of soybean seedlings exposed to stressful environments. Thus, this study was conducted to select soybean genotypes exposed to stressful environments (saline or drought) using similarity based on Manhattan distance and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. TOPSIS is a multi-criteria decision method for selecting the best alternative using the concept of distance. The use of TOPSIS is essential because the genotypes are not absolutely similar in both treatments. That is, just the distance measure is not enough to select the best genotype simultaneously in the two stress environments. Drought and saline stresses were induced by exposing seeds of 70 soybean genotypes to -0.20 MPa iso-osmotic solutions with polyethylene glycol-PEG 6000 (119.6 g L-1) or NaCl (2.36 g L-1) for 14 days at 25 °C. The germination rate, seedling length, and seedling dry matter were measured. We showed here how the genotypic stability of soybean plants could be quantified by TOPSIS when comparing drought and salinity conditions to a non-stressful environment (control) and how this method can be employed under different conditions. Based on the TOPSIS method, we can select the best soybean genotypes for environments with multiple abiotic stresses. Among the 70 tested soybean genotypes, RK 6813 RR, ST 777 IPRO, RK 7214 IPRO, TMG 2165 IPRO, 5G 830 RR, 98R35 IPRO, 98R31 IPRO, RK 8317 IPRO, CG 7464 RR, and LG 60177 IPRO are the 10 most stable genotypes under drought and saline stress conditions. Owing to high stability and gains with selection verified for these genotypes under salinity and drought conditions, they can be used as genitors in breeding programs to obtain offspring with higher resistance to antibiotic stresses.

Selected Indices to Identify Water-Stress-Tolerant Tropical Forage Grasses.

Periods of soil water stress have been recurrent in the Cerrado region and have become a growing concern for Brazilian tropical pasture areas. Thus, the search for forage grasses more tolerant to water stress has intensified recently in order to promote more sustainable livestock. In a greenhouse experiment, the degree of water stress tolerance of nine tropical forage grass cultivars was studied under different soil water regimes. The investigation followed a 9 × 3 factorial design in four randomized blocks. Nine cultivars from five species of perennial forage grasses were tested: Urochloa brizantha ('BRS Piatã', 'Marandu', and 'Xaraés'), Panicum maximum ('Aruana', 'Mombaça', and 'Tanzânia'), Pennisetum glaucum ('ADR 300'), Urochloa ruziziensis ('Comum'), and Paspalum atratum ('Pojuca'). These cultivars were grown in pots under three soil water regimes (high soil water regime-HSW (non-stressful condition), middle soil water regime-MSW (moderate water stress), and low soil water regime-LSW (severe water stress)). Plants were exposed to soil water stress for 25 days during the tillering and stalk elongation phases. Twelve tolerance indices, including tolerance index (TOL), mean production (MP), yield stability index (YSI), drought resistance index (DI), stress tolerance index (STI), geometric mean production (GMP), yield index (YI), modified stress tolerance (k1STI and k2STI), stress susceptibility percentage index (SSPI), abiotic tolerance index (ATI), and harmonic mean (HM), were calculated based on shoot biomass production under non-stressful (YP) and stressful (YS) conditions. Soil water stress decreased leaf area, plant height, tillering capacity, root volume, and shoot and root dry matter production in most cultivars, with varying degrees of reduction among tropical forage grasses. Based on shoot biomass production under controlled greenhouse conditions, the most water-stress-tolerant cultivars were P. maximum cv. Mombaça and cv. Tanzânia under the MSW regime and P. maximum cv. Aruana and cv. Mombaça under the LSW regime. P. maximum cv. Mombaça has greater adaptability and stability of shoot biomass production when grown under greenhouse conditions and subjected to soil water stress. Therefore, this forage grass should be tested under field conditions to confirm its forage production potential for cultivation in tropical regions with the occurrence of water stress. The MP, DI, STI, GMP, YI, k2STI, and HM tolerance indices were the most suitable for identifying forage grass cultivars with greater water stress tolerance and a high potential for shoot biomass production under LSW regime.

Understanding the contribution of soybean crop residues inoculated with Bradyrhizobium spp. and not harvested on nitrogen supply in off-season corn cultivars.

Excessive rainfall in the soybean preharvest period can make mechanized crop harvesting technically and economically unfeasible, causing 100% losses in soybean grain yield. An alternative to reduce the economic losses of farmers would be using unharvested soybean crop residues as a source of nitrogen (N) for the subsequent corn crop. However, a question that still needs to be understood is whether the amount of N released from unharvested soybean residues (straw and grains) is sufficient to meet all the nutritional demand for this nutrient in the off-season corn. Therefore, this study investigated the impact of unharvested soybean crop residue persistence on the yield response of off-season corn crop (Zea mays L.) to the application of N fertilizer rates when grown in tropical Cerrado soils of medium and high fertility. Four simple corn hybrids (SYN7G17 TL, 30F53VYHR, B2433PWU, and AG 8700 PRO3) were grown in soils of medium fertility and medium acidity level (UFMS 1) and high fertility and low acidity level (UFMS 2) and fertilized with five of N fertilizer rates (0, 40, 80, 120, and 160 kg ha-1 of N) applied at 30 days after emergence (DAE). Canonical correlation analysis (CCA) was used to investigate the interrelationships between the groups of independent (agricultural production areas, corn cultivars, and N application rates) and dependent (corn agronomic traits) variables. Crop residues remaining on the soil surface from soybeans not harvested and inoculated with Bradyrhizobium spp. can supply most of the nitrogen requirement of off-season corn grown in succession, especially in tropical soils of medium fertility. However, in high-fertility tropical soils, the maximum grain yield potential of off-season corn cultivars can be obtained with the application of mineral N fertilizer in supplement the amount of nitrogen released from unharvested soybean residues. Therefore, the N requirement depends on the corn cultivar and the agricultural production area. However, our results show that when off-season corn is grown on unharvested soybean residues, nitrogen fertilization in topdressing can be dispensed. The agricultural area with high fertility soil (UFMS 2) enhances the grain yield of the off-season corn crop. The corn cultivar AG 8700 PRO3 has a higher thousand-grain mass and high grain yield potential under Brazilian Cerrado conditions.

Salinity effects on water potential and the normalized difference vegetation index in four species of a saline semi-arid ecosystem.

This study was carried out during January 2020-December 2020 in a semi-desert ecosystem in southern Sonora, Mexico, to determine the annual and daily variations in water potential and the normalized difference vegetation index (NDVI) of Bursera fagaroides Engl., Monogr. Phan., Parkinsonia aculeata L., Sp. Pl.; Prosopis laevigata (Humb. & Bonpl. ex Willd.), and Atriplex canescens (Pursh) Nutt. Soil electrical conductivity, cation content, and physical characteristics were determined at two depths, and water potential (ψ) was measured in roots, stems, and leaves. The daily leaf ψ was measured every 15 days each month to determine the duration of stress (hours) and the stress intensity (SI). The electrical conductivity determinations classified the soil in the experimental area as strongly saline. A significant difference was noted in electrical conductivity between soil depths. The four studied species showed significant gradients of ψ in their organs. In this soil, all four species remained in a stressed condition for approximately 11 h per day. The mean SI was 27%, and B. fagaroides Engl., Monogr. Phan. showed the lowest value. The four species showed increased NDVI values during the rainy months, with P. laevigata (Humb. & Bonpl. ex Willd.) and Parkinsonia aculeata L., Sp. Pl. showing the highest values. The capacity for ψ decrease under saline conditions identified A. canescens (Pursh) Nutt., B. fagaroides Engl., Monogr. Phan. and P. aculeata L., Sp. Pl. as practical and feasible alternatives for establishment in saline soils in southern Sonora for purposes of soil recovery and reforestation.

Correlations and path analysis in agronomic traits of soybeans under defoliation / Correlações e análise de trilha em caracteres agronômicas de soja sob desfolha

Stress events or leaf damage can alter the redistribution of photoassimilates and modify the morphological traits directly related to grain yield. This study aimed to evaluate the influence of agronomic traits on grain yield in soybean crop in function of leaf defoliation. The experiment consisted of a randomized block design with three replications, arranged in a 6 x 3 + 1 factorial scheme. The factors were composed by six reprodutive stages (R1, R2, R3, R4, R5, and R6) and three defoliation levels (33%, 66%, and 99%), and one additional treatment without defoliation (control). The following traits were evaluated: plant height, number of pods per plant, number of grains per pod, thousand grain weight, and grain yield. The magnitudes of the correlations between the same traits showed high oscillation according to the defoliation level. Results revealed the potential for the indirect selection for grain yield by the traits plant height and number of grains per pods under 0% of defoliation and by the trait number of pods per plant under 33% of defoliation.

Ocorrências de estresse ou danos foliares podem levar a alteração na redistribuição de fotoassimilados e modificar os caracteres morfológicos envolvidos diretamente na produtividade dos grãos. Portanto, objetivou-se avaliar por meio da análise de trilha, a influência de caracteres agronômicos na produtividade de grãos na cultura da soja em função de níveis desfolha da planta. O delineamento experimental utilizado foi o de blocos casualizados com três repetições, dispostos em esquema fatorial 6 x 3 + 1. O primeiro fator foi composto por seis estádios reprodutivos de desfolha (R1, R2, R3, R4, R5, R6) x três níveis de desfolha (33%, 66%, 99%) e um tratamento adicional sem desfolha (controle). Os caracteres avaliados foram: altura de plantas, número de legumes por planta, número de grãos por legume, peso de mil grãos e produtividade de grãos. As magnitudes das correlações entre os mesmos caracteres apresentaram alta oscilação de acordo com o nível de desfolha, sendo que, que existe potencial da seleção indireta para produtividade de grãos por meio da altura de plantas e número de grãos por legumes sob 0% desfolha e do número de legumes por planta sob 33% de desfolha.

Genetic Characterization of a Wheat Association Mapping Panel Relevant to Brazilian Breeding Using a High-Density Single Nucleotide Polymorphism Array.

Bread wheat (Triticum aestivum L.) is one of the world's most important crops. Maintaining wheat yield gains across all of its major production areas is a key target toward underpinning global food security. Brazil is a major wheat producer in South America, generating grain yields of around 6.8 million tons per year. Here, we establish and genotype a wheat association mapping resource relevant to contemporary Brazilian wheat breeding programs. The panel of 558 wheat accessions was genotyped using an Illumina iSelect 90,000 single nucleotide polymorphism array. Following quality control, the final data matrix consisted of 470 accessions and 22,475 polymorphic genetic markers (minor allele frequency ≥5%, missing data <5%). Principal component analysis identified distinct differences between materials bred predominantly for the northern Cerrado region, compared to those bred for southern Brazilian agricultural areas. We augmented the genotypic data with 26 functional Kompetitive Allele-Specific PCR (KASP) markers to identify the allelic combinations at genes with previously known effects on agronomically important traits in the panel. This highlighted breeding targets for immediate consideration - notably, increased Fusarium head blight resistance via the Fhb1 locus. To demonstrate the panel's likely future utility, genome-wide association scans for several phenotypic traits were undertaken. Significant (Bonferroni corrected P < 0.05) marker-trait associations were detected for Fusarium kernel damage (a proxy for type 2 Fusarium resistance), identifying previously known quantitative trait loci in the panel. This association mapping panel represents an important resource for Brazilian wheat breeding, allowing future genetic studies to analyze multiple agronomic traits within a single genetically diverse population.

Fatty Acid and Lipopolysaccharide Effect on Beta Cells Proteostasis and its Impact on Insulin Secretion.

Metabolic overload by saturated fatty acids (SFA), which comprises ß-cell function, and impaired glucose-stimulated insulin secretion are frequently observed in patients suffering from obesity and type 2 diabetes mellitus. The increase of intracellular Ca2+ triggers insulin granule release, therefore several mechanisms regulate Ca2+ efflux within the ß-cells, among others, the plasma membrane Ca2+-ATPase (PMCA). In this work, we describe that lipotoxicity mediated mainly by the saturated palmitic acid (PA) (16C) is associated with loss of protein homeostasis (proteostasis) and potentially cell viability, a phenomenon that was induced to a lesser extent by stearic (18C), myristic (14C) and lauric (12C) acids. PA was localized on endoplasmic reticulum, activating arms of the unfolded protein response (UPR), as also promoted by lipopolysaccharides (LPS)-endotoxins. In particular, our findings demonstrate an alteration in PMCA1/4 expression caused by PA and LPS which trigger the UPR, affecting not only insulin release and contributing to ß-cell mass reduction, but also increasing reactive nitrogen species. Nonetheless, stearic acid (SA) did not show these effects. Remarkably, the proteolytic degradation of PMCA1/4 prompted by PA and LPS was avoided by the action of monounsaturated fatty acids such as oleic and palmitoleic acid. Oleic acid recovered cell viability after treatment with PA/LPS and, more interestingly, relieved endoplasmic reticulum (ER) stress. While palmitoleic acid improved the insulin release, this fatty acid seems to have more relevant effects upon the expression of regulatory pumps of intracellular Ca2+. Therefore, chain length and unsaturation of fatty acids are determinant cues in proteostasis of ß-cells and, consequently, on the regulation of calcium and insulin secretion.

Utility of Shear Wave Elastography for Assessing Allograft Fibrosis in Renal Transplant Recipients: A Pilot Study.

OBJECTIVES: To evaluate the utility of ultrasound-based shear wave elastography (SWE) as a noninvasive method to accurately detect and potentially stage the severity of renal allograft fibrosis and assess its user reproducibility. METHODS: In this Institutional Review Board-approved, Health Insurance Portability and Accountability Act-compliant prospective study, 70 renal transplant recipients underwent an SWE evaluation of their allograft followed directly by biopsy. Two radiologists performed separate SWE measurement acquisitions and the mean, median, and standard deviation of 10 SWE measurements, obtained separately within the cortex and the medulla, were automatically computed. Each patient's SWE results were subsequently compared to their histologic fibrosis scores. The Fisher exact test and univariate logistic regression models were fit to test for associations between the presence of fibrosis (yes/no) as well as categorical SWE results based on the fibrosis severity, ranging from F0 (no fibrosis) to F3 (severe fibrosis), correlating with histologic scores according to the 2007 Banff classification system. Interobserver and intraobserver correlations were also examined. RESULTS: Our median medulla SWE values reached statistical significance (P = .04) in association with fibrosis. Furthermore, for every unit increase in the median medulla SWE measurement, the odds of fibrosis increased by approximately 20%. No statistical significance was found for mean cortical, median cortical, or mean medullary SWE values (P = .32, .37, and .06, respectively) in association with fibrosis. CONCLUSIONS: The use of SWE for assessing renal allograft fibrosis is challenging but promising. Further investigation with a larger sample size remains to validate our initial results and establish clinical relevance.

Challenges and Considerations When Using Shear Wave Elastography to Evaluate the Transplanted Kidney, With Pictorial Review.

The gold standard in evaluating renal allograft dysfunction has traditionally been renal biopsy. However, not only does biopsy come with inherent risks, the time frame from biopsy to detecting renal dysfunction is often inefficient. It is therefore advantageous to have a noninvasive, low-cost, time-saving method, such as shear wave elastography (SWE), to detect fibrosis early, to maximize immunosuppressive care. It is important to consider factors that affect tissue stiffness in the kidney, as well as the challenges incurred when using SWE in this anisotropic organ, in order to select the most appropriate patients for this exam.

Alleles of organic acid transporter genes are highly correlated with wheat resistance to acidic soil in field conditions.

KEY MESSAGE: TaALMT1 and TaMATE1B promoter alleles are highly correlated with wheat growth in acidic soil with a high concentration of toxic aluminium. The aluminium (Al(3+)) resistance of 338 wheat genotypes with different geographic origins was correlated with morphological traits and TaALMT1 and TaMATE1B alleles. Both of these genes encode malate and citrate transporters associated with Al(3+) resistance mechanisms in wheat. Based on comparisons with the sensitive and resistant controls, the relative root growth was evaluated in hydroponic experiments and the plant performance was visually accessed in the field. The correlation between Al(3+) tolerance in the hydroponic and field tests was moderate (r = 0.56, P < 0.001). Higher selection pressure was observed in the field because a smaller number of genotypes was classified as resistant. The combination between the six TaALMT1 alleles and the two TaMATE1B promoters allowed the identification of 11 haplotypes that showed a high (r = 0.71, P < 0.001) correlation with Al(3+) resistance in the field, with the TaALMT1 alleles accounting for most of the correlation. The Brazilian wheat genotypes presented the best performance in soil, including eight cultivars with promoters usually associated with Al(3+) resistance and another six genotypes classified as moderately resistant but containing alleles usually associated with Al(3+) sensitivity. Although an increase in favourable alleles was observed over the past few decades, the average Al(3+) resistance in the field was not significantly different from that of older cultivars. The ease identification of the TaALMT1 and TaMATE1B alleles and their higher association with Al(3+) resistance along with the best genotypes identified here may be used for wheat-breeding programmes interested in increasing wheat Al(3+) resistance.

Synonymous site variation due to recombination explains higher genetic variability in begomovirus populations infecting non-cultivated hosts.

Begomoviruses are ssDNA plant viruses that cause serious epidemics in economically important crops worldwide. Non-cultivated plants also harbour many begomoviruses, and it is believed that these hosts may act as reservoirs and as mixing vessels where recombination may occur. Begomoviruses are notoriously recombination-prone, and also display nucleotide substitution rates equivalent to those of RNA viruses. In Brazil, several indigenous begomoviruses have been described infecting tomatoes following the introduction of a novel biotype of the whitefly vector in the mid-1990s. More recently, a number of viruses from non-cultivated hosts have also been described. Previous work has suggested that viruses infecting non-cultivated hosts have a higher degree of genetic variability compared with crop-infecting viruses. We intensively sampled cultivated and non-cultivated plants in similarly sized geographical areas known to harbour either the weed-infecting Macroptilium yellow spot virus (MaYSV) or the crop-infecting Tomato severe rugose virus (ToSRV), and compared the molecular evolution and population genetics of these two distantly related begomoviruses. The results reinforce the assertion that infection of non-cultivated plant species leads to higher levels of standing genetic variability, and indicate that recombination, not adaptive selection, explains the higher begomovirus variability in non-cultivated hosts.