Functional Plant Biology最新文献

Our previous experiments confirmed that two mulberry spermidine synthase (SPDS) genes (MnSPDS1 and MnSPDS2) that encode functional proteins are highly expressed under drought stress. In this study, the functions of MnSPDS1/MnSPDS2 in the drought stress response were further explored by silencing and overexpressing these genes in mulberry and tobacco, respectively. Compared with the wild-type (WT) plants, the MnSPDS1/MnSPDS2-overexpression tobacco plants were more tolerant to drought stress and showed a higher spermidine content (P < 0.05). Moreover, overexpression of MnSPDS1/MnSPDS2 at the physiological level alleviated membrane damage caused by drought and improved osmotic regulation and antioxidant capacity. In addition, correlation analysis showed that the content of spermidine was positively correlated with the expression levels of MnSPDS1 and MnSPDS2, with correlation coefficients of 0.762 and 0.715, respectively. Moreover, drought injury was more serious in the MnSPDS-silenced seedlings than in the WT seedlings after drought treatment. These results suggest that MnSPDS genes play important roles in the drought stress response and are valuable for molecular breeding to enhance the drought tolerance of mulberry.

GmbHLHm1 is a basic Helix-Loop-Helix membrane (bHLHm1) DNA binding transcription factor localized to the symbiosome membrane and nucleus in soybean (Glycine max ) nodules. Overexpression of GmbHLHm1 significantly increased nodule number and size, nitrogen fixation activity,and nitrogen delivery to the shoots. This contrasts with reduced nodule numbers per plant, nitrogen fixation activity and poor plant growth when silenced using RNAi. The promoter of GmbHLHm1 was found to be sensitive to exogenous GA supply, decreasing the level of GUS expression in transformed hairy roots in both nodules and roots and reducing native GmbHLHm1 expression in wild-type nodules. In summary, our study suggests that GmbHLHm1 positively regulates soybean nodulation and nitrogen fixation, and that GA can negatively regulate GmbHLHm1 expression in soybean nodules.

Conventional breeding of date palm (Phoenix dactylifera ) is inherently challenging due to its long generation time, dioecious nature, and high genetic heterogeneity. However, current developments in genomics and molecular biology offer promising avenues for accelerating breeding programs, particularly through high-throughput technologies including functional genomics. This article reviews genomic tools such as like CRISPR-Cas9 (Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-associated protein 9) that may bring significant changes in date palm breeding. The CRISPR-Cas9 system enables scientists to accurately target genomic regions, which helps enhance breeding accuracy by adding advantageous traits and eliminating unfavorable genes through precision editing. Transcriptome and metabolome analyses have also explained the regulation of thousands of differentially expressed genes (DEGs) and metabolic pathways under environmental stress. These studies contribute to enhance the knowledge of stress tolerance mechanisms, which include the secondary metabolic process of flavonoids. Genomic studies illustrating single nucleotide polymorphism (SNP)-based diversity between cultivars from north African and the Arabian Gulf provide new genetic resources for selective breeding. The work relates genome-wide association studies (GWAS) and miRNA profiling to elucidate key regulatory networks involved in fruit development and stress resilience. The integration of such advanced technologies, especially the CRISPR-Cas9 system, is revolutionizing the landscape of date palm breeding, opening new avenues for accelerated development of superior cultivars that meet the needs of modern agriculture.

Agastache rugosa is an herbaceous species that shows a high degree of phenotypic plasticity in response to light and nutrient gradients, but the coordination among its leaf structural, photosynthetic, and resource use traits remains unexplored in tropical environments. We investigated the functional traits and resource use efficiencies of A. rugosa under four nutrient levels nested within two light levels. Photosynthetic rates increased under high-light, while leaf temperatures remained stable (34-37°C) across treatments, suggesting effective thermoregulation. Unexpectedly, Rubisco content was 22.4% higher under low-light, intermediate nutrient levels, indicating a compensatory mechanism. Water use efficiency increased under high-light, whereas photosynthetic phosphorus and potassium use efficiencies were higher under low-light levels. Principal component analysis showed that light and nutrients explained 71.6% of trait variation, with distinctive clustering of resource use efficiencies. Hierarchical clustering identified three functional trait groups at 90% similarity levels, comprising photosynthetic, nutrient use, and water conservation mechanisms. The species showed tight coordination between CO2 supply and demand, with strong correlations between photosynthetic traits and resource use efficiencies. Our findings demonstrate that A. rugosa employs a suite of adaptive mechanisms to optimise resource acquisition and utilisation across heterogeneous environments, advancing our understanding of plant responses to multiple resource gradients.

We aimed to identify the genes encoding predominant KEGG enzymes within the rhizospheric soil fungiome of Moringa oleifera . We also aimed to uncover how the rhizospheric fungiome drives intricate biochemical networks that bolster soil health, plant vitality, nutrient cycling, metabolic efficiency and resilience to environmental stress. These findings offer valuable insights that could enhance the efficacy of innovative agricultural practices. Previous research has focused on the role of soil microbiomes, including both bacteriomes and fungiomes, in the ecological dynamics of native and cultivated plants. The rhizospheric fungiome plays a critical role in plant health by suppressing pathogens, decomposing plant residues and facilitating nutrient assimilation in various environmental conditions. Fungal taxa from the phylum Mucoromycota, including Rhizophagus , Mucor ambiguus , Phycomyces blakesleeanus , Mortierella elongata , Absidia glauca , Mucor circinelloides and the taxon Basidiobolus meristosporus from Zoopagomycota, were identified as primary hosts of Kyoto Encyclopedia of Genes and Genomes (KEGG)-enriched enzymes in the rhizospheric soil of M. oleifera . These enzymes participate in crosstalk pathways within KEGG categories such as 'Metabolism', 'Genetic Information Processing', and 'Environmental Information Processing'. These fungal enzymes contribute to the biosynthesis of critical metabolites, including carbamoyl-P, lipoyllysine, acetyl-CoA, isoleucine, valine and nucleotides (dADP, dGDP, dCDP, dUDP) that are essential for cellular functions such as DNA repair, replication and transcription. The symbiotic relationship between these enzymes and plant roots regulates nitrogen levels in the rhizosphere and supports mitochondrial stability. Metabolites also aid in cellular development, membrane metabolism, plant signal transduction and energy metabolism, including fueling the citric acid cycle. Our findings highlight the potential of crosstalking pathways in the rhizospheric fungiome of M. oleifera to enhance energy metabolism and maintain plant cell integrity. We propose that this research can serve as a foundation for advancing sustainable agricultural practices.

Rice is a substantial cereal crop and staple food in several world regions. Nitrogen (N) and potassium (K) are key to increasing rice growth and development, ultimately increasing the farmer's net profit. Environmental pollution also results from the careless application of nitrogenous fertilizers for commercial agricultural cultivation. Understanding the metabolic profiling underlying rice nitrogen use efficiency (NUE) is still limited. Therefore screening these two cultivars on a commercial and economic basis is essential, as this would be beneficial in revealing new insights. The flag leaf metabolic expression profiles of two rice cultivars, IRRI 6 (V1) and ksk 434 (V2), collected from low and high NK treatments at anthesis were examined. The optimal doses were applied to 45-day-old transplanted seedlings. Our findings revealed that in response to the NK application, ksk 434 (V2) yielded higher values for morphological traits such as total dry weight, plant height, total number of tillers, rice flag leaf weight, total fresh weight and rice flag leaf area than basmati 385 (V1). Furthermore, N2K2 (114:104kg/ha) application significantly increased NUE, rice grain yield, chlorophyll content and metabolic expression compared to plants treated with N1K1, N3K3 and the control. Twenty-four metabolites related to photosynthetic synthesis were annotated, among which 8-Acetylegelolide, citric acid, methionine, chlorophyll a/b and (S)-2-Aceto-2-hydroxybutanoate were positively correlated with the photosynthetic cycling process. Meanwhile, UDP-glucose, 4-methylcellulose, galactosamine, L-glutamic acid and C5-branched dicarboxylic acid metabolism were positively associated with yield. Furfural, L-piperidine and (S)-2-acetone-2-hydroxybutyric acid were downregulated after nitrogen application in both cultivars compared to control. The optimum dose of fertilizer application also upregulated the expression of NAPDH, ndhA, ndhD, ATP1, psAc, ndhB and rpoB genes in the flag leaf of rice at the heading stage as compared to control plants. In future, multiomics techniques will be performed to identify key genes/pathways involved in N metabolism, that may potentially improve root architecture and increase NUE.

Plants have evolved complex defense mechanisms against biotic stressors. Many plant defense-related genes that play crucial roles in regulating defense responses have been identified in common bean (Phaseolus vulgaris L.). However, the functional roles of phenylalanine ammonia-lyase (PvPAL ), lipoxygenase (PvLOX ), glutathione S-transferase (PvGST ) and peroxidase (PvPOD ) in response to herbivory and wounding remain unclear in common bean. In this study, we investigated the expression patterns of PvPAL, PvLOX, PvGST and PvPOD genes in common bean under wounding and infestation by a major pest, Helicoverpa armigera , using quantitative real-time PCR (qRT-PCR) for the first time. The expression patterns of these genes in response to insect attack and wounding were compared. Moreover, the effects of wounding and H. armigera on the chlorophyll fluorescence parameters (F v /F m , PI ABS , ABS/RC, TRo/RC, ETo/RC and DIo/RC ) were also determined in common bean. Our results revealed that all genes were significantly upregulated in response to H. armigera , whereas PvPAL and PvPOD were downregulated in wounding. Notably, PvLOX and PvGST genes may play significant roles in the defense system of common bean against both wounding and H. armigera infestation. Furthermore, significant reductions in F v /F m , PI ABS and ETo/RC were determined under both wounding and H. armigera infestation. These findings suggest that H. armigera is more severe than wounding, leading to distinct gene expression profiles and photosynthetic responses in common bean. The study provides valuable insights for both researchers and breeders in future studies associated with insect stress and resilience breeding efforts.

In light of climate change, improving plant resilience to abiotic stress is essential. Iodine application can improve plant tolerance to abiotic stress and provide humans with a nutritious diet rich in iodine and antioxidants. A field experiment was conducted on lettuce plants grown in a saline environment with four levels of foliar iodine spray (0, 3, 6, and 9mg/L potassium iodate). Lettuce plants respond to iodine in a concentration-dependent manner, with low iodine concentrations increasing their antioxidant capacity, reducing the amount of toxic compounds, improving their nutritional status, maintaining their physiological balance, and stimulating plant growth and yield. Conversely, high iodine levels disrupt physiological processes and reduce productivity. However, lettuce plants sprayed with 3mg/L iodine presented relatively high levels of antioxidant enzymes (catalase, superoxide dismutase, and ascorbate peroxidase), nonenzymatic antioxidants (vitamin C, proline, and phenols), chlorophyll, and nutrients, as well as relatively low levels of malondialdehyde, H2 O2 , and Na, resulting in increased head weight and total yield and reduced nitrate content. Thus, while low levels of iodine can increase plant resilience to adverse conditions such as salt stress, high levels can be detrimental, leading to reduced growth and yield. The higher the concentration of iodine used, the greater the inhibitory effect on plants.

Ensuring food security and solving the issues brought on by climate change require breeding and engineering of climate-resilient crops. Despite its contributions to reducing agricultural diseases, genetic engineering has several limitations, including high labor costs, lengthy processing times, and poor productivity. Genome editing has become a potential method to provide notable opportunities to explain complex biological processes, genetically solve the causes of diseases, and improve crops for disease resistance by effectively modifying multiple traits. Genome editing techniques including TALENs, ZFNs, and CRISPR/Cas9 increase agricultural productivity by developing climate-resistant crops and promoting climate-resilient agriculture. Among these approaches, CRISPR/Cas9 shows exceptional efficacy, minimal chance of off-target effects, and improved traits such as drought tolerance and disease resistance. This study explores advanced gene editing techniques for improving disease resistance in crops and developing climate-resilient varieties to reduce food insecurity and hunger. It demonstrates that these techniques have enhanced the nutritional content and resilience of many crops by fighting abiotic and biotic stresses. Future agricultural practices could alter the genes and improve disease-resistant crops by genome editing techniques.

Soil salinisation is increasing in extent and area, which seriously limits the growth of crops. In this experiment, we investigated the differences in physiological responses and salt (NaCl) tolerance thresholds between salt-tolerant ('Xinluzao 53') and salt-sensitive ('Xinluzao 60') varieties of cotton (Gossypium hirsutum ). Peroxidase activity of 'Xinluzao 53' and 'Xinluzao 60' increased by 29.37% and 59.35%, compared with the control, respectively. Catalase activity of 'Xinluzao 53' and 'Xinluzao 60' was 101.00% and 61.59% higher than that of the control, respectively. Overall increase of malondialdehyde (MDA) content in the leaves of 'Xinluzao 53' was less than 'Xinluzao 60', which was lower in 'Xinluzao 53' than 'Xinluzao 60' under the salt treatments of 8g kg-1 (32.59% lower) and 10g kg-1 (35.27% lower). Net photosynthetic rate (Pn) of 'Xinluzao 60' was reduced by 13.31%, 22.83%, and 21.52% compared to 'Xinluzao 53' at salt concentrations of 2, 8, and 10g kg-1 , respectively. 'Xinluzao 53' protected the cell membrane structure by maintaining higher antioxidant enzyme activities, lower MDA content, and electrolyte leakage under salt stress. Higher SPAD values, chlorophyll fluorescence parameters and photosynthetic rates were further maintained to safeguard normal physiological metabolism and photosynthetic system, higher salt tolerance than 'Xinluzao 60'. The orrelation analysis and quadratic regression equation established an integrated, comprehensive, and reliable screening method for cotton seedling salt tolerance threshold in combination with the actual growth of seedlings. The salt tolerance threshold of salt-tolerant 'Xinluzao 53' seedlings was 10.1g kg-1 , and the salt tolerance threshold of sensitive 'Xinluzao 60' seedlings was 8.5g kg-1 .