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Common wheat (Triticum aestivum L.) is a major staple food crop, providing a fifth of food calories and proteins to the world's human population. Despite the impressive growth in global wheat production in recent decades, further increases in grain yield are required to meet future demands. Here we estimated genetic gain and genotype stability for grain yield (GY) and determined the trait associations that contributed uniquely or in combination to increased GY, through a retrospective analysis of top-performing genotypes selected from the elite spring wheat yield trial (ESWYT) evaluated internationally during a 14-year period (2003 to 2016). Fifty-six ESWYT genotypes and four checks were sown under optimally irrigated conditions in three phenotyping trials during three consecutive growing seasons (2018-2019 to 2020-2021) at Norman E. Borlaug Research Station, Ciudad Obregon, Mexico. The mean GY rose from 6.75 (24th ESWYT) to 7.87 t ha-1 (37th ESWYT), representing a cumulative increase of 1.12 t ha-1. The annual genetic gain for GY was estimated at 0.96% (65 kg ha-1 year-1) accompanied by a positive trend in genotype stability over time. The GY progress was mainly associated with increases in biomass (BM), grain filling rate (GFR), total radiation use efficiency (RUE_total), grain weight per spike (GWS), and reduction in days to heading (DTH), which together explained 95.5% of the GY variation. Regression lines over the years showed significant increases of 0.015 kg m-2 year-1 (p < 0.01), 0.074 g m-2 year-1 (p < 0.05), and 0.017 g MJ-1 year-1 (p < 0.001) for BM, GFR, and RUE_total, respectively. Grain weight per spike exhibited a positive but no significant trend (0.014 g year-1, p = 0.07), whereas a negative tendency for DTH was observed (- 0.43 days year-1, p < 0.001). Analysis of the top ten highest-yielding genotypes revealed differential GY-associated trait contributions, demonstrating that improved GY can be attained through different mechanisms and indicating that no single trait criterion is adopted by CIMMYT breeders for developing new superior lines. We conclude that CIMMYT's Bread Wheat Breeding Program has continued to deliver adapted and more productive wheat genotypes to National partners worldwide, mainly driven by enhancing RUE_total and GFR and that future yield increases could be achieved by intercrossing genetically diverse top performer genotypes.

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Global warming poses a major threat to food security and necessitates the development of crop varieties that are resilient to future climatic instability. By evaluating 149 spring wheat lines in the field under yield potential and heat stressed conditions, we demonstrate how strategic integration of exotic material significantly increases yield under heat stress compared to elite lines, with no significant yield penalty under favourable conditions. Genetic analyses reveal three exotic-derived genetic loci underlying this heat tolerance which together increase yield by over 50% and reduce canopy temperature by approximately 2 °C. We identified an Ae. tauschii introgression underlying the most significant of these associations and extracted the introgressed Ae. tauschii genes, revealing candidates for further dissection. Incorporating these exotic alleles into breeding programmes could serve as a pre-emptive strategy to produce high yielding wheat cultivars that are resilient to the effects of future climatic uncertainty.

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Objetivo: Describir la frecuencia y localización de pato- logías y anomalías dentarias (anomalías de número, tumores, quistes y piezas retenidas) observadas en radiografías pa- norámicas de pacientes pediátricos de entre 6 y 15 años del Hospital Zonal Especializado en Odontología Infantil "Dr. A. Bollini" de la ciudad de La Plata. Materiales y métodos: Se realizó un estudio observa- cional descriptivo de 300 radiografías panorámicas, de niños (n=150) y niñas (n=150) de entre 6 y 15 años, seleccionadas aleatoriamente en el área de radiología del hospital, tomadas en el período comprendido entre marzo de 2018 y marzo de 2020. Los datos obtenidos se volcaron en planillas de cálculo y con ellos se realizó un análisis estadístico descriptivo. Se utilizaron las siguientes variables: edad, sexo, tipo de ano- malía o patología (anomalías de número, tumores, quistes y piezas retenidas), pieza dentaria y ubicación (maxilar o man- díbula). Resultados: Dentro de las anomalías registradas (n=147), se encontraron en mayor medida piezas dentarias retenidas, en un 44,22% de los casos (n=65), agenesias en un 42,18% de los casos (n=62) y supernumerarios en un 13,61% de los casos (n=20). No se hallaron quistes ni tumores. Conclusión: En un 24% de las radiografías panorámicas de niños entre 6 y 15 años se halló alguna anomalía dentaria. Las anomalías más frecuentes fueron piezas dentarias reteni- das y agenesias (AU)

Aim: To describe the frequency and location of dental pathologies and anomalies (number anomalies, tumors, cysts and retained dental pieces) observed in panoramic radio- graphs of pediatric patients between 6 and 15 years of age from the Hospital Especializado en Odontología Infantil "Dr. A. Bollini" from the city of La Plata. Materials and methods: A descriptive observational study was performed based on 300 panoramic radiographs of children (150 girls and 150 boys) between 6 and 15 years old, randomly selected in the Radiology area of the hospital, taken in the period between March 2018 and March 2020. The data obtained were entered into spreadsheets and a descriptive sta- tistical analysis was carried out. The following variables were evaluated: age, sex, type of anomaly or pathology (anomalies of number, tumor, cysts and retained dental pieces), dental piece and location (maxilla or mandible). Results: Among the registered anomalies (n=147), re- tained dental pieces were found to a greater extent, in 44.22% of the cases (n=65), agenesis in 42.18% of the cases (n=62) and supernumeraries in 13.61% of the cases (n=20). No cysts or tumors were found. Conclusion: In 24% of panoramic radiographs of chil- dren between 6 and 15 years old, some dental anomaly was found. The most frequent anomalies were retained dental pieces and agenesis (AU)

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Grain yield (YLD) is a function of the total biomass (BM) and of partitioning the biomass by grains, i.e., the harvest index (HI). The most critical developmental stage for their determination is the flowering time, which mainly depends on the vernalization requirement (Vrn) and photoperiod sensitivity genes (Ppd) loci. Allelic variants at the Vrn, Ppd, and earliness per se (Eps) genes of elite spring wheat genotypes included in High Biomass Association Panel (HiBAP) I and II were used to estimate their effects on the phenological stages BM, HI, and YLD. Each panel was grown for two consecutive years in Northwest Mexico. Spring alleles at Vrn-1 had the largest effect on shortening the time to anthesis, and the Ppd-insensitive allele Ppd-D1a had the most significant positive effect on YLD in both panels. In addition, alleles at TaTOE-B1 and TaFT3-B1 promoted between 3.8% and 7.6% higher YLD and 4.2% and 10.2% higher HI in HiBAP I and II, respectively. When the possible effects of the TaTOE-B1 and TaFT3-B1 alleles on the sink and source traits were explored, the favorable allele at TaTOE-B1 showed positive effects on several sink traits mainly related to grain number. The favorable alleles at TaFT3-B1 followed a different pattern, with positive effects on the traits related to grain weight. The results of this study expanded the wheat breeders' toolbox in the quest to breed better-adapted and higher-yielding wheat cultivars.

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The mechanism of action of the anti-Listeria peptide enterocin CRL35 was studied with biophysical tools by using lipid mixtures that mimicked Gram-positive plasma membranes. Langmuir monolayers and infrared spectroscopy indicated that the peptide readily interacted with phospholipid assembled in monolayers and bilayers to produce a dual effect, depending on the acyl chains. Indeed, short chain mixtures were disordered by enterocin CRL35, but the gel-phases of membranes composed by longer acyl chains were clearly stabilized by the bacteriocin. Structural and functional studies indicated that non-bilayer states were formed when liposomes were co-incubated with enterocin CRL35, whereas significant permeabilization could be detected when bilayer and non-bilayer states co-existed. Results can be explained by a two-step model in which the N-terminal of the peptide firstly docks enterocin CRL35 on the lipid surface by means of electrostatic interactions; then, C-terminal triggers membrane perturbation by insertion of hydrophobic α-helix.

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One of the major challenges for plant scientists is increasing wheat (Triticum aestivum) yield potential (YP). A significant bottleneck for increasing YP is achieving increased biomass through optimization of radiation use efficiency (RUE) along the crop cycle. Exotic material such as landraces and synthetic wheat has been incorporated into breeding programmes in an attempt to alleviate this; however, their contribution to YP is still unclear. To understand the genetic basis of biomass accumulation and RUE, we applied genome-wide association study (GWAS) to a panel of 150 elite spring wheat genotypes including many landrace and synthetically derived lines. The panel was evaluated for 31 traits over 2 years under optimal growing conditions and genotyped using the 35K wheat breeders array. Marker-trait association identified 94 SNPs significantly associated with yield, agronomic and phenology-related traits along with RUE and final biomass (BM_PM) at various growth stages that explained 7%-17% of phenotypic variation. Common SNP markers were identified for grain yield, BM_PM and RUE on chromosomes 5A and 7A. Additionally, landrace and synthetic derivative lines showed higher thousand grain weight (TGW), BM_PM and RUE but lower grain number (GM2) and harvest index (HI). Our work demonstrates the use of exotic material as a valuable resource to increase YP. It also provides markers for use in marker-assisted breeding to systematically increase BM_PM, RUE and TGW and avoid the TGW/GM2 and BM_PM/HI trade-off. Thus, achieving greater genetic gains in elite germplasm while also highlighting genomic regions and candidate genes for further study.

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