Search Results (1,031)

Rice is a staple food grown worldwide. While white rice varieties have been extensively studied, there is limited information on the performance of pigmented rice genotypes and their tolerance to water deficit. This study evaluated nineteen black rice genotypes and one white cultivar over three years under contrasting water regimes: traditional flooding and non-flood irrigation (NFI). Genotype–environment interactions and their impact on agronomic, yield, and grain quality traits were assessed. Black genotypes under NFI showed reduced flowering and grain quality. The average yield was 31% lower than the white cultivar. Significant genetic correlations were found between grain yield and days to anthesis (DSA), grain weight (TGW), chalkiness (CHA), and translucency (TRAN), with high broad-sense heritability (H² > 0.9). Most traits exhibited high heritability (H² > 0.7), indicating strong genetic stability. Grain yield (GR) was highly and negatively correlated with percent sterility (PS) (r = −0.84) and had a heritability of 0.76. Environmental conditions significantly influenced yield, confirming the potential for selecting water stress–tolerant genotypes. These findings provide valuable insights into black rice breeding and optimizing water management practices to support sustainable production. To our knowledge, this study is the first to evaluate the performance of a diverse set of black rice genotypes across multiple seasons under contrasting water regimes in a Mediterranean environment. Full article

Forest-type national nature reserves and their surrounding areas have experienced a series of drought events, which have influenced forest ecosystem stability. Assuming that drought events do not cause a shift in the ecosystem’s stable state, we quantified the stability of forest ecosystems in China’s national nature reserves and their surrounding areas in response to drought events from 2000 to 2018, using satellite-observed Enhanced Vegetation Index (EVI) and Standardized Precipitation Index (SPI) data. We further examined differences in ecosystem stability across regions and forest types, and identified the impacts of environmental factors using correlation analysis, analysis of variance (ANOVA), and random forest models. The results show that both national nature reserves and their surrounding areas primarily experienced single, moderate-intensity drought events, most of which occurred in spring and summer. Compared with surrounding areas, national nature reserves exhibited higher ecosystem stability, with a mean drought resistance index of 31.45 ± 21.09. The difference in ecosystem stability between reserves and their surrounding areas was most pronounced in deciduous forests, which was attributed to their high hydraulic conductivity and distinctive leaf phenological traits. Additionally, climatic factors were the dominant drivers of both resistance and recovery rate, each contributing more than 30% to the overall explained variance. Our results provide valuable guidance for enhancing drought resilience and promoting the sustainable management of China’s national forest reserves. Full article

Durum wheat (Triticum durum Desf.) underpins semolina value chains in water-limited regions, yet Peru remains import-dependent due to constrained local adaptation. We evaluated eleven elite lines plus the commercial variety ‘INIA 412 Atahualpa’ across three contrasting semi-arid sites in Arequipa (Santa Elena, San Francisco de Paula, Santa Rita) during 2023–2024 to identify genotypes maximizing performance and stability. Grain yield, thousand-kernel weight (TKW), hectoliter weight, and plant height were analyzed with combined analysis of variance (ANOVA), the additive main effects and multiplicative interaction (AMMI) and genotype and genotype-by-environment (GGE) biplots, complemented by AMMI stability value (ASV) and weighted average of absolute scores and best yield index (WAASBY). Grain yield and hectoliter weight showed significant genotype × environment (G × E) interaction, while plant height was driven mainly by genotype and environment with limited interaction. For grain yield, AMMI (PC1: 55.2%) and GGE (PC1 + PC2: 90.2%) revealed crossover responses and three practical mega-environments: TD-053 “won” at San Francisco de Paula, TD-037 at Santa Elena, and TD-033 at Santa Rita. Additionally, WAASBY-integrated rankings favored TD-033 (93.7%) and TD-014 (84.72%), followed by TD-026/TD-020 (>57%), whereas TD-062 (9.1%) and TD-043/TD-061 underperformed. Quality traits highlighted TD-044 and TD-014 for high hectoliter weight and TD-014/TD-062 for high TKW with contrasting stability. Overall, TD-033 and TD-014 were adaptable across environments, providing selection guidance to strengthen Peru’s durum breeding pipeline under climate variability. Full article

This study evaluated the responses of five sunflower (Helianthus annuus L.) hybrids (Surimi CL, Integral CL, Alexa SU, Neta SU, and Davero SU) to three planting densities (84,034, 68,027, and 57,143 plants/ha) in terms of agronomic performance and photosynthetic efficiency. Higher plant density reduced leaf area and seed weight but enhanced uniformity of head formation. Among the tested hybrids, Integral CL and Surimi CL demonstrated superior performance under high density, maintaining higher chlorophyll content, photosynthetic activity, and yield stability. In contrast, Davero SU performed best under low density, characterized by greater leaf expansion, seed filling, and overall productivity. These findings highlight the potential of integrating physiological and agronomic traits to inform hybrid-specific planting density optimization under diverse environmental conditions. Full article

This study investigates the distribution patterns, interspecific relationships, and community stability mechanisms of phytoplankton functional groups, aiming to elucidate the ecological processes that drive phytoplankton communities in aquatic ecosystems of arid regions. We conducted seasonal sampling from 2023 to 2024 at four auxiliary reservoirs in the Tarim River Basin, namely Shangyou Reservoir (SY), Shengli Reservoir (SL), Duolang Reservoir (DL), and Xinjingzi Reservoir (XJZ). In recent years, researchers have grouped phytoplankton into functional groups based on their shared morphological, physiological, and ecological characteristics—with these three types of traits serving as the core criteria for distinguishing different functional groups. A total of 18 functional groups were identified from the phytoplankton collected across four seasons, among which eight (A, D, H1, L0, M, MP, P, and S1) are dominant. Redundancy Analysis (RDA) indicated that environmental factors such as pH, electrical conductivity (COND), and dissolved oxygen (DO) are key driving factors affecting phytoplankton functional groups. Interspecific association analysis showed that the phytoplankton communities in DL, SL, and XJZ reservoirs were dominated by positive associations, reflecting stable community structures that are less prone to drastic fluctuations under stable environmental conditions. In contrast, the SY Reservoir was dominated by negative associations, indicating that it is in the early stage of succession with an unstable community. This may be related to intense human disturbance to the reservoir and its role in replenishing the Tarim River, which leads to significant water level fluctuations. The results of the Chi-square test and Pearson correlation analysis showed consistent trends but also differences: constrained by the requirement for continuous normal distribution, Pearson correlation analysis identified more pairs of negative associations, reflecting its limitations in analysing clumped-distributed species. Random forest models further indicated that functional groups M, MP, L0, and S1 are the main positive drivers of interspecific relationships. Among them, the increase in S1 can promote the growth of functional groups dominated by Navicula sp. and Chroococcus sp. by reducing resource competition. Conversely, the expansion of functional group H1 inhibits other groups, which is related to its adaptive strategy of resisting photo-oxidation in eutrophic environments. This study reveals the patterns of interspecific interactions and stability mechanisms of phytoplankton functional groups in arid-region reservoirs, providing a scientific basis for the management and conservation of aquatic ecosystems in similar extreme environments. Full article

The seed lots were evaluated based on their viability and vigor, which vary according to their origin and the locations where the seeds were produced. However, differences in vigor can be observed within a single seed lot, resulting from the deposition of photoassimilates. In this context, the hypothesis of this study is that distinct locations on the plant may produce seeds with different physiological quality. Therefore, the objective of this work was to evaluate how pod position influences the vigor of seeds from different soybean genotypes. Field experiments were conducted during the 2021/22 and 2022/23 crop seasons in Brazil. The experimental design was a randomized complete block with four replications and 32 soybean populations from the UFMS/CPCS Breeding Program. During the R4, R5, R6, and R7 reproductive stages of soybean, at the time of pod formation, the plants in each block were tagged with string to delimit the uppermost point at which pods had formed. Tagging was carried out as each stage change was verified, at approximately eight-day intervals. When analyzing how the pod position of the plant influences seed physiological variables, we found that position P1 was responsible for the best results for the variables evaluated, with the exception of genotypes G18 and G28. This result indicates that pods from the first position produce seeds with greater germination capacity and a higher ability to generate normal seedlings. However, the genotypes are still under development and, therefore, do not yet exhibit stability. Nevertheless, the results obtained highlight the relationship between the pod position of the plant and seed physiological variables. The position of the pods on the soybean plant influences the physiological quality of the seeds. In general, the P1 position, when the plants are in the R4 reproductive stage, with fully developed pods measuring 2 cm on one of the four upper nodes of the stem, is responsible for the best results in seed physiological quality tests for most of the soybean genotypes evaluated. These results indicate that pod position should be considered in breeding and seed production programs, since genotypes with greater physiological stability in the upper positions may be preferential in selection strategies. In the future, studies in different environments and evaluation of biochemical traits may confirm these patterns and contribute to the development of cultivars with higher seed quality and physiological uniformity. Full article

Background: Faculty burnout in allied healthcare education institutions represents a significant challenge with implications for educational quality, organizational effectiveness, and healthcare workforce development. This scoping review aims to map the existing literature on the relationships between leadership approaches, faculty personality factors, and burnout within allied healthcare education, while examining digital competence as a potential moderating factor. Methods: This scoping review followed the PRISMA-ScR guidelines. Five electronic databases (MEDLINE, CINAHL, ERIC, PsycINFO, and Web of Science) were searched for relevant studies published between 2010 and 2024. Studies examining burnout among allied healthcare educators in relation to leadership, personality traits, or digital competence were included. Data extraction captured study characteristics, methodological approaches, key findings, and theoretical frameworks. Quality assessment was conducted using the Mixed Methods Appraisal Tool. Results: Sixteen studies met the inclusion criteria. Existing research indicates significant relationships between leadership styles and faculty burnout rates, with transformational leadership consistently associated with lower burnout scores. The literature reveals that individual personality traits demonstrate significant relationships with burnout vulnerability, with emotional stability and extraversion showing the strongest protective effects. Limited research has examined digital competence in relation to burnout, though emerging evidence suggests it may function as a moderating factor. Significant gaps exist in non-Western contexts and in understanding interaction effects between leadership, personality, and digital competence. Conclusions: The current literature supports the importance of leadership approaches that emphasize collaboration, faculty autonomy, recognition, and professional development opportunities in protecting against burnout in allied healthcare education settings. Digital competence represents a promising but understudied job resource that may mitigate burnout effects. Future research should explore cross-cultural variations, interaction effects between personal and organizational factors, and the effectiveness of interventions in reducing faculty burnout. Full article

Background: Some lactobacilli strains have been documented to cause bacteremia and sepsis in immunocompromised or critically ill hospitalized patients, challenging the universally presumed safety of lactobacilli. Therefore, strain-specific risk assessments are required for the use of Lactobacillus as a probiotic. Lactobacillus xujianguonis, a novel Lactobacillus species isolated from Marmota himalayana, has probiotic potential but lacks safety data. Objective: To evaluate the preclinical safety of L. xujianguonis for food-grade use. Methods: Systematic safety assessment includes in vitro studies and oral toxicity studies. In vitro studies encompassed gastrointestinal tolerance, auto-aggregation and pathogen inhibition, antibiotic susceptibility, and hemolysis/gelatinase activity assays. Oral toxicity studies contained acute single-dose and repeated-dose 28-day oral toxicity studies in mice based on the OECD toxicity study guidelines. Results: L. xujianguonis strains HT111-2 and 06-2 demonstrated certain probiotic traits, including high acid/bile tolerance, strong auto-aggregation, and antimicrobial activity against common human gastrointestinal pathogens. In vitro safety assessments showed susceptibility to nine antibiotics and absence of hemolytic/gelatinase activity. Acute oral exposure (1 × 10¹¹ CFU/kg) induced no mortality, clinical abnormalities, or organ toxicity. Subchronic 28-day administration (multiple doses) showed absence of adverse clinical signs with body weight stability and no hematological, biochemical, or histopathological deviations in C57BL/6 mice. Inflammatory and immunological markers remained unaffected. Histological staining results and transcriptional level validation revealed no evidence of intestinal tissue damage. Conclusions: This study provides preliminary evidence of the safety of L. xujianguonis, supporting its advancement to functional research. Full article

Phages play a role in shaping ecosystems by controlling host abundance via cell lysis, driving host evolution via horizontal gene transfer, and promoting nutrient cycling. The genus Bradyrhizobium includes bacteria able to symbiotically nodulate the roots of soybean (Glycine max), providing the plant with a direct source of biologically fixed nitrogen. Optimizing this symbiosis can minimize the use of nitrogen fertilizers and make soybean production more sustainable. Phages targeting Bradyrhizobium may modify their hosts’ genotype, alter phenotypic traits such as symbiotic effectiveness, and mediate competition among strains for nodulation sites. Sixteen phages were isolated against B. diazoefficiens strain USDA110 and B. elkanii strains USDA94 and USDA31. Comparative analyses revealed host species-dependent diversity in morphology, host range, and genome composition, leading to the identification of three previously undescribed phage species. Remarkably, all B. elkanii phages shared a siphophage morphology and formed a single species with >97% nucleotide identity, even when isolated from farms separated by up to ~70 km, suggesting genomic stability across geographic scales. In contrast, phages isolated against B. diazoefficiens had a podophage-like morphology, exhibited greater genetic diversity, and divided into two distinct species. Although no phages were recovered against the B. japonicum strains or native Delaware Bradyrhizobium isolates tested, some Delaware Bradyrhizobium isolates showed susceptibility in a host range assay. The phage genomes demonstrated features predicting phenotypes. The phage terminase genes predicted headful packaging which promotes generalized transduction. The B. elkanii phages all carried tmRNA genes capable of rescuing stalled ribosomes, and all but one of the phages isolated against the two host species carried DNA polymerase A indicating greater phage control of genome replication. State-of-the-art structural annotation of a hypothetical gene shared by the B. diazoefficiens phages, having a mean amino acid identity of ~25% and similarity of ~35%, predicted a putative tail fiber function. Together this work expands the limited knowledge available on soybean Bradyrhizobium phage ecology and genomics. Full article

Cotton production in Mediterranean regions is increasingly constrained by limited water availability, making it essential to identify genotypes that can maintain yield under reduced irrigation. In this study, four partially interspecific cotton lines (Pa7) and the commercial cultivar Celia were evaluated under two nitrogen rates designed to test resource-use efficiency and three irrigation regimes across two growing seasons in Greece. A strip–split plot design with three replications was used, and field data were analyzed with ANOVA, stability indices, and multivariate tools (Additive Main Effects and Multiplicative Interaction—AMMI, and Genotype plus Genotype × Environment—GGE biplots). Results showed that moderate irrigation consistently ensured stable seed cotton yields, whereas a higher water supply increased the plant height without proportional yield benefits, while fertilizer supplied in the specific quantities showed a lower impact on yield stability. Genotype × environment interactions were highly significant: Celia confirmed its high stability, while line M3 combined good stability with favorable agronomic traits. Yield was strongly associated with boll weight and lint percentage, indicating their usefulness as indirect selection criteria. These findings highlight the agronomic potential of partially interspecific cotton lines and demonstrate that moderate irrigation can sustain productivity while reducing water inputs, contributing to a more efficient use of resources in cotton production under water-limited conditions. These results provide practical insights for breeding and water management strategies aiming to sustain cotton productivity under Mediterranean water-limited conditions. Full article

Cacti of the genera Opuntia and Nopalea exhibit morphophysiological and biochemical characteristics that favor their adaptation to semiarid environments, such as crassulacean acid metabolism (CAM) and cladode succulence. These strategies reduce water loss and allow the maintenance of photosynthesis under stress conditions. In this study, we evaluated the seasonal variation in the physiological and photochemical responses of forage cactus clones grown in semiarid environments, considering the rainy, dry, and transition seasons. The net photosynthetic rate (P_n) and chlorophyll fluorescence parameters varied significantly as a function of water availability and microclimatic conditions. We found higher CO₂ assimilation rates during the rainy season, while the dry season resulted in a strong impairment of photosynthetic activity, with reductions of 65% in stomatal conductance, 37% in transpiration, 20% in maximum quantum efficiency of photosystem II, and 19% in the electron transport rate. Furthermore, during these periods, we observed an increase in initial fluorescence and non-photochemical dissipation, demonstrating the activation of photoprotective mechanisms against excess light energy. During the transition seasons, the cacti exhibited rapid adjustments in gas exchange and energy dissipation, indicating the adaptive plasticity of CAM pathway. The MIU (Nopalea cochenillifera (L.) Salm-Dyck), OEM (Opuntia stricta (Haw.) Haw.), and IPA (Nopalea cochenillifera (L.) Salm-Dyck) clones demonstrated greater resilience, maintaining greater stability in P_n, instantaneous water use efficiency, and photochemical parameters during the drought. In contrast, the OEA (Opuntia undulata Griffiths) clone showed high sensitivity to water and heat stress, with marked reductions in physiological and photochemical performance. In summary, the photosynthetic efficiency and chlorophyll fluorescence of CAM plants result from the interaction between water availability, air temperature, radiation, and genotypic traits. This study provides a new scientific basis for exploring the effects of environmental conditions on the carbon and biochemical metabolism of cacti grown in a semiarid environment. Full article

To elucidate the temporal dynamics of genetic diversity across successive breeding generations of channel catfish (Ictalurus punctatus) and enhance subsequent breeding efficiency, we systematically evaluated the genetic variation in four consecutive generations using ten highly polymorphic microsatellite loci. The number of alleles (Na), effective alleles (Ne), and Shannon’s index (I) all declined with increasing generations. The mean expected heterozygosity (He) decreased gradually from 0.822 to 0.805 but remained above 0.80, indicating that all generations maintained relatively high genetic diversity. Allele frequency analysis revealed the progressive fixation of alleles potentially linked to target traits, while some rare alleles were gradually lost. Analysis of molecular variance (AMOVA) demonstrated that 98% of the genetic variation occurred within generations, with weak differentiation among generations (Fst = 0.016). UPGMA clustering further indicated that later generations diverged from the base stock, whereas genetic distances among adjacent generations progressively narrowed, suggesting increasing convergence and stabilization of genetic structure. These findings provide both theoretical insights and practical guidance for the continuous selective breeding and germplasm conservation of channel catfish. Full article

This study investigates meteorological factors’ effects on summer maize growth, agronomic traits and yield in northeastern Sichuan, China, under different sowing dates. A five-gradient sowing date experiment was conducted with three varieties from 2023 to 2024. The results showed delayed sowing prolonged total growth period mainly in the joint–tasseling and silking–maturity stages. Early sowing (5th May and 20th May) significantly improved key agronomic traits and increased grain yield, with Xianyu 1171 achieving the highest yield of 9.77 t ha⁻¹ under early sowing. Meteorological factors had limited influence during vegetative growth but strongly affected reproductive growth. Among them, average temperature (AT) and growing degree days (GDDs) were critical throughout the growth cycle, though their effects varied by stage. These findings suggest that adjusting sowing dates to align key growth stages with favorable weather—particularly by avoiding high-temperature stress during flowering and ensuring sufficient warmth during grain filling—can enhance yield stability. This study provides a basis for constructing a climate-resilient cultivation system and promoting stable and high summer maize yields in the hilly areas of northeastern Sichuan. Full article

The role of the rhizosphere microbiome in naturally suppressing soilborne diseases remains a critical unknown in sustainable agriculture. We investigated this by challenging three genotypes of tomato plants grown in pre-sterilized and natural soils with three major soil-borne pathogens: Ralstonia solanacearum, Fusarium oxysporum f. sp. lycopersici, and Meloidogyne incognita. The results showed that all tomato genotypes grown in pre-sterilized soils exhibited significantly higher disease severity with all pathogens. This protective effect was linked to higher microbial diversity and the abundance of beneficial taxa like Sphingomonas and Mortierella in natural soil as a significant reduction was recorded in microbial diversity and these microbial taxa in pre-sterilized soil. Pre-sterilization shifted community assembly from deterministic processes to stochastic processes, reducing functional stability. Functional predictions further demonstrated an enrichment of growth-promoting and disease-suppressive traits in natural soils, while sterilized soils favored pathogen-associated functions. Co-occurrence network analysis confirmed that the natural microbiome formed a more complex and robust microbial network, likely increasing its resistance to pathogen invasion. Notably, the reintroduction of soil microbiota from healthy plants partially restored tomato resistance to the three pathogens. These findings highlight the key role of stable rhizosphere microbial communities in suppressing soil-borne diseases and emphasize the importance of conserving microbial diversity and functional stability for plant health and sustainable agriculture. Full article

Direct seeding of winter rapeseed in the Yangtze River Basin often coincides with low temperatures during establishment. The aim of this study was to test whether low-temperature (LT) germination performance predicts overwintering survival and yield under delayed sowing. Thirty accessions were evaluated in controlled germination at 20/14 °C (CK) and 12/6 °C (LT) and in two field seasons (2020–2021 and 2021–2022), with six sowing dates from 15 October to 4 December. Mean germination rate was 97.6% in CK and 88.0% in LT. Germination potential (GP) averaged 95.7% in CK and 41.9% in LT. Root and shoot length decreased from 7.63 and 5.02 cm in CK to 1.47 and 0.48 cm in LT. Overwintering survival declined with later sowing. In the colder season (2020–2021), survival for sowings after November fell below 20% for most accessions, whereas S1–S2 averaged above 80%. Yield decreased with delay. In 2021–2022, yield under S1 exceeded S2–S6 by 5.5%, 8.5%, 13.9%, 14.0%, and 23.3%. In 2020–2021, S1 was similar to S2, but 6.3–22.8% higher than S3–S6. Thousand-seed weight followed the same trend. LT GP and LT root length were positively correlated with yield at several sowing dates in the colder season, indicating that LT germination traits are predictive of late-sown performance under harsher winters. Seven accessions (3409, M417, Zheza0903, 86155, 3445, Zheyou50, and 3462) showed superior LT germination and comparatively better field performance. For the lower Yangtze site, a practical latest safe sowing window is late October, based on two seasons; November sowing substantially increases winter mortality and yield risk. Selecting genotypes with strong LT germination and managing for rapid autumn establishment can stabilize 1000-seed weight and yield when sowing is delayed. Full article