BMC Plant Biology最新文献

Apricot is one of Türkiye's most important horticultural crops, accounting for approximately 21% of global production. The Hacıhaliloğlu cultivar, responsible for 90% of the country's dried apricot exports, is cultivated in Malatya, where declining precipitation due to climate change poses a significant threat to sustainable production. This study, conducted from 2021 to 2023, aimed to evaluate the effects of different drought irrigation regimes on the morpho-physiological and biochemical characteristics of Hacıhaliloğlu apricot trees under water stress. Four-year-old T-budded saplings were grown in pots and subjected to monthly irrigation treatments during the post-harvest period.The results revealed that drought stress significantly inhibited shoot elongation, reduced leaf size and dry matter accumulation, and impaired pistil development. The T₀ treatment (full irrigation) consistently outperformed all other regimes in terms of shoot length, pistil length, specific leaf weight, and relative leaf dry weight. Drought-exposed trees, especially those under rainfall-only or late irrigation conditions (T₁, T₇, T₈), exhibited increased oxidative damage, as indicated by elevated levels of membrane permeability, H₂O₂, MDA, and antioxidant enzyme activities (CAT, POD, SOD). Moreover, leaf water potential and chlorophyll content declined under prolonged stress conditions.These findings emphasize that irrigation during critical developmental stages particularly July and August, when flower bud differentiation and vegetative growth overlaps is vital for preserving productivity and physiological integrity in apricot trees. Strategic water management in arid and semi-arid regions can mitigate the negative effects of drought stress and enhance tree performance even under limited water availability.

Background: Morus mongolica holds significant value in medicinal applications, livestock fodder production, and ecological restoration. Although polyploidization is well-documented in plants for enhancing stress tolerance and altering nutrient composition, the specific beneficial traits conferred by genome duplication in M. mongolica have not yet been fully characterized.

Results: Our results demonstrated that a 72 h preculture followed by 72 h of colchicine treatment (30 mg·L^-¹), yielded a tetraploid rate of 25%. Significant differences were observed between diploid and tetraploid plants in plant height, basal diameter, leaf area, and chlorophyll content. Furthermore, tetraploids exhibited significantly higher levels of total sugars, Ca, Se, total phenols, and flavonoids, compared to diploid M. mongolica. Also, tetraploid plants are better equipped to endure extended periods of drought stress, ultimately resulting in improved survival rates, through earlier drought perception and more finely tuned physiological regulation.

Conclusion: This study established an effective tetraploid induction protocol for M. mongolica, characterized the beneficial traits of the induced tetraploids, and thereby lays the foundation for tetraploid induction and breeding.

Background: Functional traits are pivotal indicators of plant ecological strategies, regulating resource acquisition and allocation through traits trade-offs. However, few studies have explored how trait coordination underlying resource-use strategies vary across plant life-forms from different trait dimensionalities. In this study, we examined 14 leaf functional traits in 81 plant species (27 herbaceous and 54 woody species) from the southwestern Qinling Mountains, including 6 structural traits (leaf area, leaf thickness, leaf mass per area, leaf dry matter content, leaf tissue density, and leaf volume), 4 chemical traits (leaf carbon, nitrogen, and phosphorus concentrations and nitrogen-to-phosphorus ratio), and 4 photosynthetic traits (maximum net photosynthetic rate, stomatal conductance, internal-to-ambient carbon dioxide ratio, and photosynthetic nitrogen use efficiency).

Results: Our findings revealed divergent distribution ranges between herbaceous and woody plants along the leaf economics spectrum, with herbaceous plants at the resource acquisition end (e.g., high nutrient concentration and photosynthesis rate) and woody plants at the resource conservation end (e.g., high tissue density). Furthermore, herbaceous plants exhibited higher connectivity in their trait networks, with leaf area as the hub trait, emphasizing efficient resource utilization through optimized light interception. In contrast, woody plants showed greater modularity, with leaf dry mass content as the hub trait, reflecting enhanced flexibility to environmental pressures by prioritizing maintenance and defense.

Conclusions: These findings advance our understanding of how trait coordination mediates plant adaptative strategies across multiple dimensions and underscore the functional importance of plant hub traits in modulating resource use strategy across plant life-forms.

Yam (Dioscorea spp.) encompasses diverse species, including several staple food crops, of which a few were domesticated on the African continent. This study assessed yam genetic diversity in Sub-Saharan Africa (SSA) to inform breeding and conservation initiatives. A diverse collection of 1,247 yam accessions representing six species (D. rotundata, D. alata, D. praehensilis, D. bulbifera, D. cayenensis, and D. dumetorum) sourced from six African countries (Benin, Côte d'Ivoire, Democratic Republic of Congo, Ghana, Nigeria, and Uganda) was used in this study. Genetic diversity was assessed using 7,648 single-nucleotide polymorphism (SNP) markers, selected from previously sequenced datasets between the Consultative Group on International Agricultural Research (CGIAR) and National Agricultural Research and Extension Systems (NARES) collaboration. Findings showed a substantial inter- and intra-specific variation in African yam germplasm, with observed heterozygosity ranging from 0.165 to 0.464 and an average polymorphic information content (PIC) of 0.324 across populations. Population structure was assessed using ADMIXTURE (with cross-validation error for optimal K), DAPC (with BIC for K), and an IBS-based Neighbor-Joining (NJ) tree. Analysis of molecular variance (AMOVA) indicated moderate differentiation among countries (FST = 0.07), and higher differentiation among species (average FST = 0.14). Clustering patterns and phylogenetic analysis revealed the presence of evolutionary relationships among D. cayenensis, D. praehensilis, and D. rotundata, providing insights into D. rotundata domestication history in West Africa. These findings enhance our understanding of genetic relationships within the Dioscorea genus.

Background: Hexokinase (HXK) plays a key role in plant sugar metabolism and signal transduction, and is involved in regulating plant growth, development, and stress responses. To date, the HXK gene family in cucurbit crops has only been identified in melon (Cucumis melo), while systematic identification and analysis of HXK genes in cucumber (Cucumis sativus) and watermelon (Citrullus lanatus) remain lacking.

Result: In this study, six HXK genes were identified in both the cucumber (CsHXK1-CsHXK6) and watermelon (ClHXK1-ClHXK6) genomes. Phylogenetic analysis classified these genes into two types (Type A and Type B). Analyses of gene structure and conserved motifs confirmed high conservation among family members. Collinearity analysis further revealed that segmental duplication was the main driver of HXK family expansion in these two crops. Additionally, cis-acting element analysis showed that the promoter regions of CsHXK and ClHXK genes contained abundant stress-responsive elements. Using 7 publicly available cucumber transcriptome datasets and 14 publicly available watermelon transcriptome datasets, we analyzed the tissue-specific expression patterns of CsHXK and ClHXK genes, as well as their expression responses to abiotic and biotic stresses. The results showed that CsHXK1 was highly expressed in cucumber roots and flowers, while ClHXK6 exhibited broad expression across multiple watermelon tissues. Functionally, CsHXK1 was significantly up-regulated under five stress conditions (salt, waterlogging, downy mildew, powdery mildew, and angular leaf spot), and ClHXK6 showed significant differential expression under six stress conditions (salt, drought, osmotic stress, Fusarium wilt-1, Fusarium wilt-3, and squash vein yellowing virus infection). qRT-PCR validation was performed for CsHXK1 under salt stress and for ClHXK6 under salt and drought stresses, and the results consistently supported the transcriptome data, confirming the critical roles of CsHXK1 and ClHXK6 in mediating stress responses in cucumber and watermelon, respectively. This study represents the first comprehensive and systematic identification of the HXK gene family in cucumber and watermelon, coupled with an analysis of their expression patterns under diverse abiotic and biotic stresses. It provides a theoretical basis for in-depth exploration of HXK gene functions and offers valuable candidate genes (CsHXK1 and ClHXK6) for improving stress resistance in cucumber and watermelon breeding programs.