Functional Plant Biology最新文献

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 .

Calmodulin (CaM) and calmodulin-like (CML) gene families are important in combating stress conditions in plants. A total of 36 CaMs/CMLs were identified and found to be randomly dispersed over the 11 chromosomes of Citrullus lanatus (watermelon). Domain analysis verified the presence of characteristic four EF-hand domains in ClCaM proteins and 2-4 EF-hand domains in ClCML proteins. Most of the ClCML genes were intron-less, but all the ClCaM had introns. In the promoter region, 11% of the cis -regulatory elements were identified belonging to abiotic stress. Collinearity analysis suggested that the ClCaM/ClCML gene family expanded due to segmental duplications. Synteny analysis of 36 ClCaM/CML exhibited 31 pairs of collinearity with Arabidopsis thaliana . Twelve miRNAs were predicted to target one ClCaM and eleven ClCML genes. Analysis by real time quantitative PCR indicated all genes expressed under abiotic treatments. Among the analysed genes, ClCML1 is the most highly expressed gene, especially under cold stress, suggesting its strong involvement in stress response mechanisms. ClCML5 and ClCML27 showed consistent upregulation under salt and drought stresses, highlighting their potential roles in the salt and drought tolerance mechanism. These findings will facilitate the subsequent experiments in exploring the calcium signalling channel under stress situations and pave the way for further exploration of molecular mechanisms involved in defenses against cold, drought, and salt stress.

Heterosis, or hybrid vigor, represents a pivotal phenomenon in cotton (Gossypium spp.) breeding, enabling substantial advancements in yield, stress tolerance, and fiber quality. However, the underlying molecular mechanisms of this phenomenon are still largely unexplored. To address this issue, we performed RNA-seq meta-analysis using a P -value combination approach to identify key molecular signaling pathways associated with heterosis in root and bud tissues of hybrid and parental lines. In addition, the regulatory miRNA-transcription factor (TF) gene interactions associated with heterosis were further constructed and dissected. This comprehensive analysis identified 591 differentially expressed genes (DEGs) that were consistently observed in all datasets. In particular, 435 root-specific, 130 bud-specific, and 159 shared meta-DEGs were identified, revealing the intricate interplay between tissue-specific and shared molecular pathways. Functional enrichment analysis of identified meta-DEGs highlighted critical roles of specific biological processes, including circadian rhythm regulation and water transport, alongside essential metabolic pathways such as glutathione metabolism, and starch and sucrose metabolism in the heterosis phenomenon. Genes pivotal to growth and development, such as GhFT (flowering regulation), GhXTH9 (cell wall modification), and GhSUS4 (energy storage), were identified as key players in the heterosis phenomenon in cotton. The associations between several miRNA-TF-gene interaction networks such as Ghi -miR164-NAC and Ghi -miR166-HD-ZIP as heterosis driving regulatory interactions were highlighted by systems level analysis. This study provides a comprehensive framework for dissection of transcriptional regulatory mechanisms underlying heterosis in cotton and offers new insights for targeted breeding strategies to improve the performance of hybrids in modern cotton breeding programs.

Can plants remember drought? Emerging evidence suggests that prior stress exposure leaves an epigenetic imprint, reprogramming plants for enhanced resilience. However, the stability and functional relevance of drought memory remain unresolved. This review synthesizes recent advances in epigenetic modifications, transcriptional reprogramming, and metabolic priming, critically assessing their roles in plant stress adaptation. DNA methylation dynamically reshapes chromatin landscapes, yet its transient nature questions its long-term inheritance. Histone modifications, particularly H3K9ac and H2Bub1, may encode stress signatures, enabling rapid transcriptional responses, whereas small RNAs fine-tune chromatin states to reinforce memory. Beyond epigenetics, physiological priming, including osmotic adjustments, antioxidant defenses, and hormonal crosstalk, introduces further complexity, yet its evolutionary advantage remains unclear. Root system plasticity may enhance drought resilience, but its metabolic trade-offs and epigenetic underpinnings are largely unexplored. A critical challenge is disentangling stable adaptive mechanisms from transient acclimatory shifts. We propose a framework for evaluating drought memory across temporal and generational scales and highlight the potential of precision genome editing to establish causality. By integrating multi-omics, gene editing, and field-based validation, this review aims to unlock the molecular blueprint of drought memory. Understanding these mechanisms is key to engineering climate-resilient crops, ensuring global food security in an era of increasing environmental uncertainty.

Phytophthora cinnamomi is a globally destructive pathogen causing disease in over 5000 plant species. As sterol auxotrophs, Phytophthora species rely on host-derived phytosterols for reproduction, yet the effects of pathogen infection on plant sterol biosynthesis remains unclear. We utilised a soil-free plant growth system to analyze the impacts of P. cinnamomi on Nicotiana benthamiana roots, a new model for studying P. cinnamomi -plant root interactions. Our results show that P. cinnamomi successfully infected all ecotypes tested, but infection was inhibited by the systemic chemical, phosphite. While phosphite is traditionally associated with the activation of plant defence mechanisms, we show that phosphite also modulates plant immune receptors and phytosterol biosynthesis. qPCR analyses revealed a two-fold upregulation of the N. benthamiana elicitin receptor, Responsive to Elicitins (REL ), and its co-receptor, suppressor of BIR1-1 (SOBIR ) during P. cinnamomi infection when compared with infected, phosphite-treated plants. Furthermore, key genes related to plant sterol biosynthesis were upregulated in their expression during pathogen infection but were suppressed in phosphite-treated and infected plants. Notably, the cytochrome P450 family 710 (CYP710A ) gene encoding a C22-sterol desaturase, involved in stigmasterol production, a phytosterol known to be linked to plant susceptibility to pathogens, was downregulated in phosphite-treated plants, independent of infection status. These findings reveal novel insights into the role of phosphite in modulating plant immune responses and sterol metabolism, with potential in managing diseases caused by P. cinnamomi .

Early and deep sowing practices have revolutionised Australian winter cropping. Oats (Avena sativa ) are the only winter-cereal with a mesocotyl, potentially allowing them to successfully emerge from deep sowing. This study examined the genetic differences in mesocotyl and coleoptile length, the effect of temperature on these traits, and undertook a field validation of deep-sown oats compared to selected wheat (Triticum aestivum ) and barley (Hordeum vulgare ) genotypes. A controlled environment experiment on 195 oat genotypes revealed long combined mesocotyl and coleoptile lengths (112-219 mm) with significant genotypic variation. A further controlled environment study compared the mesocotyl and coleoptile lengths of 42 genotypes across four temperatures (15-30°C). This revealed that temperatures exceeding 20°C reduced coleoptile and mesocotyl length by 3.7mm and 1.1mm per °C. Five field experiments compared the emergence of 19 oat, four wheat, and two barley genotypes from deep (110mm) and shallow sowing (40mm). Oats had greater emergence at depth compared to wheat and barley genotypes. The results indicate that oats are highly suited to early and deep sowing conditions due to their long mesocotyl and combined mesocotyl and coleoptile length.