O1 Regulation of genes by telomere length over long distances

Coconut (Cocos nucifera L.) cultivation is increasingly threatened by destructive fungal pathogens that reduce yield and compromise tree health, particularly in tropical regions in China. To address this challenge, the present study aimed to isolate and identify antagonistic bacteria with potential biocontrol activity against key pathogens of coconut, including Ceratocystis paradoxa (crown rot), Pestalotiopsis menezesiana (leaf blight), and Curvularia oryzae (leaf spot). A total of 65 bacterial strains were isolated from 58 soil samples collected from healthy coconut orchards. Among these, strain X1 exhibited the most vigorous antagonistic activity, with inhibition rates exceeding 70% against multiple pathogens in both plate confrontation and mycelial growth rate assays. Morphological, physiological, biochemical, and molecular (16S rDNA and gyrB gene sequencing) analyses confirmed the identity of strain X1 as Bacillus velezensis. Optimization of fermentation conditions for strain X1 revealed that maximum antimicrobial activity was achieved using a medium containing 2% glucose, 3% peptone, 0.3% NaH₂PO₄·2H₂O, and 0.4% Na₂HPO₄·2H₂O, at 28 °C and pH 7.0–7.5, 5% inoculum, 50–70 mL liquid volume in 250 mL flasks, 72 h fermentation, and agitation at 180–220 rpm. These findings highlight B. velezensis X1 as an up-and-coming biocontrol agent with dual functionalities: effective suppression of coconut fungal pathogens and potential plant growth promotion. Its application could significantly reduce the dependence on synthetic fungicides, offering an eco-friendly alternative for integrated disease management in coconut farming.

The areca nut (Areca catechu L.) is a prominent tropical and subtropical crop of economic importance renowned for its significant medicinal value. It is recognized as one of the most prominent components of the four traditional Southern Chinese medicines. However, the lack of comprehensive genetic diversity data and reliable molecular markers has posed challenges in assessing and improving the areca nut germplasm for breeding programs. This study analyzed 196 areca nut materials, employing 40,173 high-quality single-nucleotide polymorphisms (SNPs) to evaluate the genetic relationships among the samples. Population structure analysis identified three distinct groups based on the optimal K-value, with the principal component analysis (PCA) results consistent with the results of population structure division. A phylogenetic tree constructed using the neighbor-joining method revealed clear separations among the samples based on their geographic origins. The nucleotide diversity (π) values ranged from 2.46 × 10⁻⁵ to 5.71 × 10⁻⁵, indicating limited genetic diversity within the areca nut population. The pairwise population differentiation index (Fst) revealed moderate genetic differentiation among the groups. The discovery of these SNPs will be helpful for areca nut conservation and utilization. The results of this study indicate the limited genetic diversity within areca nut germplasm resources, providing insights for management and breeding.

Wheat stripe (yellow) rust, caused by the fungus Puccinia striiformis f. sp. tritici (Pst), is one of the most threatening wheat diseases worldwide. Monitoring the virulence of Pst population is essential for managing wheat stripe rust. In this study, 18 wheat Yr single-gene lines were used to identify the virulence patterns of 67 isolates collected from 13 provinces in China in 2020, from which 33 Pst races were identified. The frequency of virulence to different Yr genes varied from 1.49% to 97.01%, with 4.48% to Yr1, 26.87% to Yr6, 11.94% to Yr7, 95.52% to Yr8, 19.40% to Yr9, 11.94% to Yr17, 2.99% to Yr24, 35.82% to Yr27, 38.81% to Yr43, 97.01% to Yr44, 8.96% to YrSP, 1.49% to Yr85, 95.52% to YrExp2, and 7.46% to Yr76. None of the isolates were virulent to Yr5, Yr10, Yr15, and Yr32. Among the 33 races, PstCN-062 (with virulence to Yr8, Yr44, and YrExp2) and PstCN-001 (with virulence to Yr8, Yr43, Yr44, and YrExp2) were the prevalent races, with frequencies of 28.36% and 11.94%, respectively. These results provide valuable information for breeding resistant wheat cultivars for controlling stripe rust.

The present study examined the cultural significance of wheat and the threat of wheat stripe rust (Puccinia striiformis f. sp. tritici) in Rawalpindi, Pakistan, aiming to protect wheat farming heritage, promote sustainable practices, and ensure future food security. A mixed-methods approach was employed to capture the multifaceted role of wheat within Rawalpindi’s social structure, traditions, and food security dynamics. Surveys and interviews revealed that most wheat fields were at the tillering and heading stages during the survey period. Sporadic disease outbreaks, particularly at the milking stage, were reported in areas such as Maira Shareef and Chakri villages, highlighting localized infections. To achieve the study objectives, the qualitative component involved in-depth interviews with 10 agricultural specialists in wheat cultivation and 12 experienced wheat farmers, selected through purposive sampling. For the quantitative component, stratified random sampling was used to engage 300 wheat farmers, providing broader insights into farming practices and disease awareness. A significant contrast emerged regarding awareness of wheat stripe rust disease. Although farmers expressed concern about its potential to reduce yields, much of the general population remained unaware of the disease. This underscores the importance of targeted awareness initiatives, such as grassroots campaigns delivered in local languages to address these knowledge gaps effectively. The study emphasized the need for collaborative efforts among stakeholders, including researchers, policymakers, and farmers, to develop disease-resistant wheat varieties. It also advocated for ecosystem-based pest management strategies to mitigate the impact of wheat stripe rust and ensure the sustainability of wheat farming traditions.

Thielaviopsis paradoxa is an important soilborne pathogen causing bleeding disease and stem rot of coconut and other palm species, posing a serious threat to coconut production in Hainan Province, China. This study investigated the biological characteristics, pathogenic variability, and genetic diversity of T. paradoxa isolates collected from coconut palms in this region, where population-level data remain limited. Isolates exhibited variability in mycelial growth and sporulation under different temperature, pH, and nutrient conditions, indicating physiological differentiation among strains. Pathogenicity assays across multiple coconut varieties revealed four pathogenicity types, with some isolates consistently showing greater aggressiveness. Genetic analysis based on ISSR markers revealed a high level of genetic diversity (82.96% polymorphism). Genetic clustering showed partial associations with geographic origin, host source, and pathogenicity patterns; however, these relationships are correlative and do not imply causality. Overall, this study provides the first region-specific synthesis of physiological traits, pathogenic variability, and ISSR-based genetic diversity of T. paradoxa in Hainan, contributing baseline information for future population genomic studies and supporting the development of improved disease management strategies for coconut palms.