Search Results (133)

Mountain ecosystems of the Northern Tian Shan harbor rare endemic plant species that are increasingly vulnerable to environmental change. This study assessed the ontogenetic stage composition, selected anatomical characteristics, and chloroplast genome features of Malus sieversii, Ribes janczewskii, and Ikonnikovia kaufmanniana. Field surveys included five populations and 971 recorded individuals: two populations of M. sieversii, one population of R. janczewskii, and two populations of I. kaufmanniana. Individuals were assigned to juvenile, immature, vegetative adult, and generative stages. The proportion of juvenile and immature individuals varied from 23.78% to 41.89% among populations, indicating substantial differences in the representation of early ontogenetic stages. Comparative anatomical analysis identified structural traits associated with adaptation to local environmental conditions. Complete chloroplast genomes were assembled and annotated, with sizes of 160,192 bp (M. sieversii), 157,432 bp (R. janczewskii), and 162,624 bp (I. kaufmanniana). All plastomes exhibited a conserved quadripartite structure and contained 131–132 genes and SSR loci with species-specific composition. Phylogenomic analysis placed M. sieversii within a well-supported wild apple clade, confirmed the distinct lineage of R. janczewskii, and supported the separation of I. kaufmanniana from Limonium. These findings provide new data and lay a basis for further studies to better understand the evolutionary distinctiveness and conservation relevance of endemic plant species in the Northern Tian Shan. Full article

This study addresses the need for effective natural inhibitors of enzymatic browning in fresh-cut produce by exploring plant-derived compounds with activity against apple polyphenol oxidase (PPO). Extracts from 26 wild plant species were screened using thin-layer chromatography (TLC)-coupled bioautographic assays specifically adapted to apple PPO. Among these, D. fullonum showed clear inhibitory activity and was selected for further investigation. Extracts from different plant organs revealed that PPO inhibition was localized in the leaves, while stems and flower receptacles were inactive. Bioautography-guided fractionation of leaf extracts enabled the isolation of active fractions, and structural characterization by HRMS and NMR indicated that the activity is associated with the iridoid glycosides sylvestrosides III and IV. Antioxidant assays (DPPH, ABTS, CUPRAC) and TLC profiling demonstrated that PPO inhibition was not directly correlated with radical scavenging activity. In situ application of the leaf extract (0.5% w/v) on fresh-cut apple slices significantly delayed browning during refrigerated storage, showing comparable or improved performance relative to ascorbic acid at later stages. These results highlight D. fullonum as a promising source of natural antibrowning agents and demonstrate the utility of food-specific bioautographic assays for the targeted discovery of functional plant metabolites. Full article

Apple Valsa canker disease, caused by Valsa mali, is one of the most destructive diseases of apple trees in China and seriously threatens the sustainable development of the apple industry. VmSom1 acts as a core transcription factor in the cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) signaling pathway and regulates vegetative growth, development and pathogenicity of this phytopathogen. Transcriptome analysis was performed using the VmSom1 deletion mutant and the wild-type strain sdau11-175, and a significantly differentially expressed transcription factor, VmGAL4, was identified. In this study, the single-gene deletion mutant ΔVmGAL4 and the double-gene deletion mutant ΔVmSom1/VmGAL4 were constructed via homologous recombination, aiming to preliminarily explore the interaction between these two genes. Sequence analysis revealed that the VmGAL4 protein contains a conserved fungal_TF_MHR domain spanning amino acids 164 to 614. Phylogenetic analysis indicated that VmGAL4 shares the closest phylogenetic relationship with homologs from Cytospora schulzeri and Cytospora chrysosperma. Phenotypic assays demonstrated that the VmGAL4 deletion mutant exhibited markedly reduced mycelial growth rate and fewer pycnidia production. Additionally, the mutant displayed enhanced sensitivity to cell wall inhibitors and osmotic stress agents, along with significantly increased capacity to utilize various carbon and nitrogen sources and decreased pathogenicity compared with the wild-type strain. Compared with the single deletion mutant ΔVmSom1, the double mutant ΔVmSom1/VmGAL4 partially rescued the growth defects and also alleviated the reduction in pathogenicity to a certain extent. Nevertheless, conidial production remained severely inhibited in the double mutant. Collectively, VmGAL4 is involved in the regulation of vegetative growth, asexual development, cell wall integrity, osmotic stress response, carbon and nitrogen source utilization, and pathogenicity in V. mali. Full article

Background: Malus sieversii, the wild ancestor of cultivated apples, possesses high stress tolerance and rich nutritional value but suffers from low fruit firmness. Jasmonate-ZIM (JAZ) domain proteins are key repressors of jasmonic acid (JA) signaling, yet their roles in fruit softening remain largely unexplored, especially in M. sieversii. Methods and results: In this study, we performed a genome-wide identification of the JAZ gene family in M. sieversii and characterized their structural features, phylogenetic relationships, chromosomal distribution, promoter cis-elements, expression patterns, and protein interactions. A total of 18 MsiJAZ genes were identified, which could be classified into six subfamilies. Most members are predicted to localize in the nucleus, while three are also potentially targeted to chloroplasts. The MsiJAZ genes are unevenly distributed across ten chromosomes and are enriched in light-, ABA-, and drought-responsive cis-elements. Expression analysis under storage and 1-MCP treatments revealed both shared and divergent responses among selected MsiJAZ genes. Notably, MsiJAZ1 was significantly repressed by storage but induced by 1-MCP and physically interacted with MsiPUB24 (PLANT U-BOX 24), an E3 ubiquitin ligase involved in ethylene-mediated softening. These results suggest that MsiJAZ1 may participate in a novel CORONATINE INSENSITIVE 1 (COI1)-independent degradation pathway and mediate ethylene–JA crosstalk during fruit softening. Conclusions: This study provides a comprehensive characterization of the JAZ family in M. sieversii and lays a foundation for further functional studies on JA signaling in apple fruit softening. Full article

Canopy SPAD index is a practical indicator for evaluating the photosynthetic status and health of Malus sieversii, an endangered wild apple resource in Xinjiang. To develop a rapid and non-destructive monitoring approach, 255 canopy samples were collected across the flower fading stage, fruit stage, and fruit mature stage using synchronized UAV hyperspectral imaging and ground SPAD measurements. Spectral preprocessing, feature-band selection, regression modeling, and SHAP interpretation were evaluated using training-set optimization and independent test-set validation. SG-FD produced the strongest preprocessing response, with a maximum absolute correlation coefficient of 0.70. SiPLS reduced 220 effective bands to 84 wavelengths; subsequent CARS, GA, and SPA screening retained 28, 8, and 12 wavelengths, respectively. The SiPLS-CARS-based Transformer-LSTM model achieved the best performance, with R² = 0.91 and RMSE = 2.12 in training and R² = 0.86 and RMSE = 2.47 in testing. SHAP results indicated that red-edge wavelengths and visible sensitive bands contributed most to prediction. The proposed UAV hyperspectral and Transformer-LSTM framework provides an interpretable proof-of-concept method for canopy SPAD index estimation in Malus sieversii and supports non-destructive monitoring of wild fruit forest health. Full article

Two wild Saccharomyces cerevisiae strains, 9-3 and 10-2, isolated from nectarine and apple leaves, show high fermentation performance in standard breadmaking but their utility in enriched-dough products remained untested. This study evaluated their performance in kouglof production against a commercial baker’s yeast as a control. Fermentation was monitored by weight loss (reflecting CO₂ production) and pH changes. Finished loaves were evaluated for macroscopic traits (weight, height, appearance), crust/crumb color, texture, and microstructure via 3D/2D analysis of gas-cell morphology. Sensory acceptance was also assessed. While size-related traits were similar across all samples, strain 10-2 significantly outperformed 9-3. Kouglof made with 10-2 exhibited commercial-grade softness, characterized by lower hardness and gumminess, lower residual sugar content, and a finer, more uniform gas-cell structure with a darker, well-developed crust, whereas 9-3 yielded a firmer crumb with fewer, larger gas cells. Sensory acceptance was comparable across variants, with all samples rated as highly acceptable. Strain 10-2 demonstrated high sucrose tolerance and performed comparably to or better than the control across multiple product-quality metrics in enriched-dough kouglof. These findings support the potential of wild yeast 10-2 for sweet bread production with high-sucrose and high-fat formulations, though further optimization is warranted. Full article

This study investigated Fusarium species associated with seven wild relatives of four economically important Rosaceae fruits in Sichuan Province, China, including wild strawberry (Fragaria sp. and Potentilla indica), wild raspberry (Rubus rosaefolius), wild cherry (Prunus sp., Maddenia sp. and Prunus leveilleana), and wild apple (Malus kansuensis). Based on multi-gene phylogenetic analyses and morphological characteristics, seven Fusarium species within the Fusarium tricinctum species complex (FTSC) were identified. Among these, four are described as new species (F. fragariae, F. potentillae, F. pruni and F. fructicola), while the remaining three represent new host records (F. avenaceum, F. diversisporum and F. paeoniae). In addition, phylogenetic and morphological evidence indicated that F. rosiradicicola is conspecific with F. diversisporum. Prioritizing the oldest epithet, we synonymized F. rosiradicicola under F. diversisporum. The pathogenicity of the isolates was evaluated on both their wild hosts and the corresponding cultivated fruits using detached, wound-inoculated assays. All tested isolates produced symptoms, showing pathogenic potential under experimental conditions. This study shows that selected wild Rosaceae fruits harbor several members of the FTSC and provides preliminary evidence of cross-host susceptibility under experimental conditions. However, further field-based investigations and non-wound inoculation studies are required to clarify their ecological roles, natural host susceptibility, and potential relevance in cultivated systems. Full article

Drought is a major limiting factor for apple growth and development. Abscisic acid (ABA) is a key hormone in plant abiotic stress responses, playing a vital role in mediating adaptation to drought. Malus sieversii, the wild ancestor of cultivated apple, exhibits superior drought tolerance. However, the specific ABA-dependent regulatory module underlying its exceptional drought tolerance remains to be elucidated. In this study, we investigated the role of ABA in the drought response of M. sieversii seedlings using a combination of exogenous ABA and the ABA biosynthesis inhibitor fluridone. Plants were subjected to four treatments: CK, PEG (20% PEG-6000), PEG+ABA (100 μM ABA) and PEG+FLU (100 μM fluridone). The results showed that ABA application significantly reduced the wilting rate by 45.53% and electrolyte leakage by 20.50% compared to the PEG treatment. Furthermore, it alleviated the decline in fresh weight and relative water content while reducing the accumulation of starch, sucrose, glucose, and fructose after seven days of stress. Conversely, FLU application intensified the adverse effects of drought. RNA-Seq analysis of the PEG+ABA vs. PEG comparison identified 5642 differentially expressed genes (DEGs), with significant enrichment in the starch and sucrose metabolism pathway, photosynthesis, carbon fixation, and MAPK signaling pathways. Exogenous ABA up-regulated BGLU23 while down-regulating BAM1. In contrast, no significant changes in their expression were observed under FLU treatment, suggesting their likely regulation in an ABA-dependent manner. In summary, ABA enhances osmotic-stress tolerance in M. sieversii through multiple pathways, among which starch and sucrose metabolism may represent a core and highly responsive regulatory pathway. Functional validation of key candidate genes BAM1 and BGLU23 remains an important direction for future investigation. These findings provide a theoretical basis for breeding drought-resistant apple rootstocks and for understanding ABA-mediated osmotic-stress tolerance mechanisms. Full article

Chemosensory systems are crucial for insect survival, enabling host-seeking, food acquisition, and oviposition site selection. While insect-associated microbes are known to influence host development and immunity, their role in modulating chemosensory behavior remains poorly understood. Here, we show that mono-association with Escherichia coli alters sensory-driven behaviors in both larval and adult axenic Drosophila melanogaster. In larvae, E. coli mono-association altered phototaxis and mechanosensory responses across genotypes, while changes in tunneling and thermosensory behaviors were reduced or absent in ionotropic receptor (IR) co-receptor mutants. In adults, E. coli mono-association increased attraction to fermentation cues (apple cider vinegar, ethanol) and enhanced sucrose consumption in wild-type and Orco-deficient flies, whereas these effects were reduced or absent in IR co-receptor mutants (IR25a⁻ and IR76b⁻). Together, these findings indicate that under defined gnotobiotic conditions, E. coli exposure alters sensory-driven behavioral outputs relative to axenic controls. Effects are reduced or absent in IR co-receptor mutants, consistent with a role for IR pathways in mediating these behavioral shifts. These findings support a role for microbial cues in shaping insect sensory-driven behaviors and highlight the importance of microbial status in interpreting behavioral phenotypes. This work provides a framework for future studies investigating how microbial signals interact with conserved sensory pathways. Full article

Colletotrichum fructicola is the predominant pathogenic agent responsible for anthracnose in Camellia oleifera. RGS2 is a GTPase-activating protein that negatively regulates G-protein signaling by inactivating Gα subunits. In this study, we characterized the ortholog of CfRGS2 in C. fructicola to explore its pathogenic roles. Seven canonical RGS genes were identified through BLASTp and keyword searches. Conserved domains and subcellular localizations were predicted bioinformatically. A CfRGS2 knockout mutant was generated via overlap-PCR and PEG-mediated transformation, verified by PCR, and complemented by reintroducing the wild-type gene. Phenotypic characterization showed that the growth rates of mutants ΔCfrgs2-1 and ΔCfrgs2-2 were significantly reduced compared with those of the wild-type and complemented strains. On both PDA and minimal medium, the mutant strains exhibited significantly smaller colony diameters of 3.3 cm and 3.1 cm, respectively, relative to the control strains. Moreover, conidiation in the mutants was only 4% of that in the wild-type and complemented strains, and appressorium formation was reduced to 6%, with statistical analyses confirming high significance. Under cell wall stress induced by 400 μg/mL Congo red, the growth inhibition rates of ΔCfrgs2-1 and ΔCfrgs2-2 were 44% and 48%, respectively, significantly higher than those of the control strains. Pathogenicity assays demonstrated that the mutants failed to induce lesions on unwounded leaves and caused 47% and 30% smaller lesion areas on wounded apple fruits, respectively. In summary, C. fructicola possesses seven canonical RGS proteins that regulate G-protein signaling, among which CfRgs2 is implicated in growth, conidiation, the stress response to cell wall perturbation, and virulence. Full article

Red pigmentation in apple peel significantly contributes to its commercial value, and bagging treatment contributes to enhancing red coloration in fruits. However, the regulatory mechanisms underlying bagging-induced coloration remain largely unexplored. Through bagging treatment, this study aimed to investigate the role of DNA methylation in anthocyanin biosynthesis in the ‘Nagafu No. 2’ cultivar and its bud mutation variant, which has enhanced red coloration. We compared bagging and unbagging treatments in both the bud mutant (Mt-Bagging and Mt-NoBagging) and the wild type (Control-Bagging and Control-NoBagging). Our results demonstrated that bagging significantly promoted anthocyanin accumulation while reducing chlorophyll content. At 30 days post-bag removal, anthocyanin content was highest in the Mt-Bagging group, followed by the Mt-NoBagging, Control-Bagging, and Control-NoBagging groups, and the highest level of redness (a* values) was detected in the Mt-Bagging group. Genome-wide methylation analysis revealed that differentially methylated regions predominantly targeted structural genes within the anthocyanin biosynthesis pathway, including C4H1, C4H3, C4HL, ANS1, and ANS2. Notably, quantitative PCR analysis confirmed that the upregulation of C4HL, C4H3, and ANS1 in the bagged mutant correlated with its intensified red coloration. These findings offer novel insights into the epigenetic regulation of apple peel pigmentation during bagging cultivation. Full article

Fumaric acid is one of the most important bio-based chemicals, with applications in the food, feed, polymer, pulp, and pharmaceutical industries. To overcome the limitations of the current petrochemical production process, alternative methods are being developed. Biotechnological production using wild-type fungi like Rhizopus sp. is a promising alternative. In this study, apple pomace was used as a carbohydrate source for fumaric acid production using Rhizopus arrhizus NRRL 1526. Our focus was on the use of free, non-structurally bound carbohydrates present in high amounts in apple pomace originating from direct apple juice processing. Three processes were compared: pressing, extraction, and a combination of both. Two cultivation strategies were applied: pre-culture and separate upstream biomass production. Using the pre-culture approach, a fumaric acid titer of 68.3 g/L was achieved with a yield of 0.53 g/g and a productivity of 0.29 g/(L·h) from synthetic apple pomace juice. Separate biomass production enabled growth-decoupled fumaric acid production, yielding 50.2 g/L and 79.3 g/L with yields of 0.82 g/g and 0.54 g/g and productivities of 0.17 g/(L·h) and 0.27 g/(L·h) from synthetic and real apple pomace juice, respectively. Thus, the efficient use of apple pomace for the fermentative production of fumaric acid is shown. Full article

Most assessments of sex pheromone-based mating disruption (MD) for codling moth (CM), Cydia pomonella (L.), have not included measurements of female mating. The recent development of a dual-sex lure (CM4K) combining ethyl (E,Z)-2,4-decadienoate, 4,8-dimethyl-1,3,7-nonatriene, pyranoid linalool oxide, and acetic acid has significantly increased the catch of female CM and made it easier to directly assess various MD programs. Samples of wild female CM populations using this lure were collected from 142 orchards, either untreated or treated with one of seven different dispenser systems for CM MD, from 2021 to 2022. The proportion of unmated females ranged from <0.20 to >0.80 with a median of 0.43 in both years. No differences in the mean proportion of unmated females were found between apple and pear. Moth immigration and supplemental insecticide sprays were hypothesized to be key factors affecting the variability within each MD tactic. Mating levels were significantly higher later in the season. More females were unmated in conventional compared with organic orchards. Means for females not mating among the CM MD programs varied over a 0.20 range, except for one. The exception occurred when two MD tactics (aerosol units plus hand-applied dispensers) were accidentally used together, and the proportion of unmated females was significantly higher. Full article

Scientific research, within the framework of a circular and sustainable economy, has increasingly focused on wild plants and agricultural by-products as valuable sources of bioactive compounds for innovative applications. In this study, the plant species selected for extract preparation and evaluation of their dyeing properties included Isatis tinctoria L., Castanea sativa, Juglans regia L., Rumex crispus L., Arbutus unedo L., and Punica granatum L. Each extract was analyzed to assess its dyeing performance on cotton and other cellulosic fabrics. Cellulose pads dyed with peels of P. granatum extract (PPGE) proved to be versatile and effective, showing potential for use in extending the shelf life of various fruits such as strawberries, apples, cherries, and persimmons. The optimum dyeing condition for cellulose and cotton fabrics was found to be 6% w/v dye. These findings support the development of natural, multifunctional materials suitable for food packaging applications aimed at preserving fresh produce, as well as for sustainable textile dyeing. Full article

During their natural growth, plants encounter adverse environmental conditions, such as chilling injury, freezing injury, drought, and salt damage, collectively known as abiotic stresses. Several studies have shown that WRKY proteins regulate various abiotic stress responses and plant developmental processes. However, researchers have rarely investigated WRKY genes associated with the stress response in apples. Within this research, Malus baccata (L.) Borkh as the experimental material. We isolated and cloned MbWRKY63 and investigated its function in low-temperature stress tolerance. Subcellular localization analysis shows that MbWRKY63 localizes to the cell nucleus. Tissue-specific expression analysis revealed that MbWRKY63 is relatively highly expressed in the young leaves and root tissues of apples. Under low-temperature treatment at 4 °C, Arabidopsis thaliana plants that overexpressed MbWRKY63 showed greater cold stress resistance than the wild type (WT) and the empty vector (UL) control. In transgenic plants, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) were significantly enhanced; meanwhile, the contents of proline, malondialdehyde (MDA), and chlorophyll also changed significantly. In addition, by regulating the expression levels of AtKIN1, AtCBF1, AtCBF2, AtCBF3, AtCOR47, and AtCOR15a, MbWRKY63 enhanced the low-temperature stress tolerance in transgenic Arabidopsis. The results suggest that MbWRKY63 in apples may be involved in the response to low-temperature stress, laying a foundation for understanding the role of WRKY transcription factors (TFs) in abiotic stress responses. Full article