Functional Plant Biology最新文献

Cotton, as a globally important economic crop, has high nitrogen (N) demand but low N uptake and N utilization efficiency (NUE). Optimizing N input by improving NUE represents a critical challenge for sustainable cotton production. We applied six N levels (0, 0.04, 0.4, 1, 4, 8mM Ca(NO3 )2 , designated as N0, N0.04, N0.4, N1, N4, and N8, respectively) to examine their effects on morphology, biomass, nutrient absorption, and NUE at four treatment durations. Results showed that seedling growth and nutrient accumulation initially increased and subsequently decreased with increasing N levels. The optimal N ranges for seedling growth at 7, 14, 21 and 28d were 0.4, 0.4-1, 1-4 and 4-8mM Ca(NO3 )2 , respectively. Under optimal N, seedlings achieved maximum accumulations of N, P, K, and Ca (55.8, 8.8, 64.9, and 26.2mg/plant at 28d, respectively), while maintaining consistent N:P:K:Ca ratios of approximately 1:0.2:1.2:0.5 across seedling stage. Under low N, nutrients were preferentially allocated to roots, promoting root growth. NUE exhibited positive correlations with root traits and nutrient proportion, whereas shoot traits showed positive associations with nutrient accumulation and shoot nutrient proportion. These findings provide a theoretical basis for scientific fertilization, and establish a theoretical foundation for understanding the physiological mechanisms of efficient N use in cotton.

Chickpea is widely grown during the cooler season to avoid the adverse effects of high-temperature stress (HTS). Endogenous ascorbic acid (AsA), a prominent antioxidant, plays a crucial role in mitigating abiotic stresses in various crops. This study aimed to assess genotypic variation in AsA and to investigate the mechanisms associated with higher AsA content. The evaluation was conducted under three HTS levels (NS: >28°C, HTS-1: >33°C, HTS-2: >37°C) in field conditions during the flowering stage. AsA accumulation increased progressively with increased stress levels, showing a 27.8% increase under HTS-1 and a 61.9% increase under HTS-2 compared to NS. Notably, genotypes JG-14, IPC-06-11, ICE-15654-A, and ICCV 92944-6 exhibited significantly higher AsA content under HTS conditions. These genotypes maintained cooler canopy temperatures, higher relative water content, and increased total chlorophyll content under HTS. Additionally, these genotypes exhibited lower lipid peroxidation rates, higher proline content, and higher ascorbate peroxidase activity. Furthermore, genotypes with higher AsA levels exhibited higher seed yield and seeds per plant. Overall, the findings indicate that genotypes with higher AsA accumulation, along with the heat-tolerant check JG-14, showed superior performance in physio-biochemical processes, suggesting that AsA plays a significant role in enhancing tolerance to HTS in chickpea.

Nickel (Ni) stress severely impairs rice growth and productivity by disrupting physiological functions and inducing oxidative damage. This study investigated the individual and combined effects of nitric oxide (NO) and L -arginine (L -Arg) in mitigating Ni toxicity in rice (Oryza sativa L.). Ni exposure reduced plant biomass, chlorophyll content, photosynthesis, water use efficiency (WUE), and membrane stability, and increased Ni uptake, reactive oxygen species (ROS), malondialdehyde (MDA), electrolyte leakage (EL), and methylglyoxal (MG). Antioxidant enzyme activities and osmolyte levels were also altered. Foliar application of NO or L -Arg partially alleviated these effects, but the combined treatment (NO+L -Arg) provided superior protection. Co-treated plants showed improved growth, chlorophyll content, gas exchange, relative water content (RWC), and leaf water potential. Oxidative stress markers (H2 O2 , MDA, EL, and MG) were reduced, whereas antioxidant enzyme and glyoxalase system activities were stabilized. Soluble sugar and glycine betaine (GB) levels were optimized, and Ni accumulation in tissues was significantly decreased. Notably, the combined treatment enhanced expression of stress-related and metal detoxification genes (OsMTP1 , OsPCS5 , HSP70 , and OsZIP1 ). These findings highlight the synergistic role of NO andL -Arg in enhancing rice tolerance to Ni stress and suggest its potential as a sustainable strategy for improving crop resilience in contaminated soils.

In recent years, use of elicitors in agriculture has received attention due to their positive effect on plant secondary metabolite production. We investigated the effects of two elicitors, magnesium oxide nanoparticles (MgO-NPs) and methyl jasmonate (MeJA) on secondary metabolites that improve physiological and stress-defensive properties of leaves and flowers of Rosa damascena Mill. Different doses of the elicitors were tested, and their impacts assessed for 14days after the leaf treatment, and at three stages of flowering. Significant increases in the contents of reactive oxygen species (ROS) and reactive nitrogen species (RNS), and in the activities of enzymatic and non-enzymatic antioxidants were found in leaves treated with the two elicitors. However, the effect was higher and widespread on all investigated parameters in plants treated with the lowest dose (0.1mM) of MeJA. Low concentrations of MeJA also clearly stimulated synthesis of monoterpenoid alcohols and aromatic alcohols that are responsible for the perfume of petals, and enhanced total and single phenolics, and total flavonoids of flowers. In contrast, petal anthocyanins were reduced following treatments with both elicitors. Exogenous applications of low concentrations of MeJA appear to be the most promising for inducing antioxidant responses in R. damascena and improving perfumes of the petals.

This study aimed to evaluate the effect of arbuscular mycorrhizal fungi (AMF) on the growth, nutrient uptake, and productivity of chickpea (Cicer arietinum). We investigated the diversity of indigenous AMF in their natural habitat and their effect on the plant and elemental characteristics of chickpea by analysing soil physicochemical properties, root colonisation, AMF spore diversity, and elemental composition of chickpea rhizosphere in two locations (Bhakkar and Khushab, Pakistan). Nitrogen levels of 5.47 g/kg and 4.51 g/kg were found in the rhizosphere soils of Bhakkar and Khushab, respectively. Root colonisation was higher (48.5%) in Khushab (Bhakkar, 35.5%), influencing phosphorus absorption in both regions. Molecular analysis identified 21 AMF taxa, with Glomus and Acaulospora being the most dominant genera. Variations in spore sizes were found, with Glomus measuring 10-191 μm, Acaulospora 125-152 μm, Sclerocystis 110-174 μm, and Gigaspora 65-184 μm. Plant analysis revealed that plant materials from Bhakkar had 1.72% ash, 1.16% fat, 3.78% fibre, and 13.05% protein; samples from Khushab had 1.90% ash, 1.25% fat, 3.24% fibre, and 11.5% protein. Elemental concentrations of chickpea plants from Bhakkar were N = 2.68%, P = 32.98 mg/kg, and K = 33.32 mg/kg, whereas those from Khushab were N = 1.94%, P = 1.17 mg/kg, and K = 43.06 mg/kg. Molecular analysis revealed AMF species with a range of 250-1100 bp. Root colonisation was inversely related to soil phosphorus levels but had a positive effect on plant moisture, fats, and carbohydrates. Morphological and molecular identification showed a relatively high AMF taxa in the rhizosphere of chickpea in both regions. Despite their benefits, the potential of AMF as biofertilisers has not been fully utilised due to prevailing agronomic practices.

As plants experience drought, transpiration is regulated by decreases in stomatal conductance (g s ) that can reduce carbon assimilation, biomass production and yield. The plant water potential (Ψ ) provides an estimate of the plant water status, and the relationship between predawn (Ψ pd ) and midday (Ψ md ) water potential (i.e. the water potential curve) could help determine when plants transition from water-consumptive (higher g s ) to water-conservative (lower g s ) behaviour. In this study, we apply the water potential curve framework (WP curve; i.e. Ψ pd ~Ψ md relationship) to an annual crop (Cucumis melo ). The WP curve was evaluated over several dry-down experiments in both greenhouse (GH) and field conditions. Leaf gas exchange and Ψ measurements were taken on the same days. Overall, the WP curve differed between environments and the shift from higher to lower g s occurred earlier (higher Ψ pd ) under GH conditions, likely driven by a smaller root system, reduced access to soil water availability and a more rapid onset of drought. The WP curve exhibited two phases divided by a breakpoint (Θ) at -0.5MPa (GH) and -0.72MPa (field) of Ψ pd that coincided with a g s reduction of 55% and 85% respectively. During phase I, plants reduced g s as the drought intensified without significantly compromising carbon assimilation (P n ). Yet, at Θ, P n decreased by 57% and 61% under GH and field conditions respectively. During phase II, leaves reached the turgor loss point (TLP) at a Ψ md of -0.83MPa (GH) and -1.3MPa (field) that were similar to the TLP estimated from bench-top leaf pressure curves. Our results suggest that the WP curve in melons identifies the transition from water-consumptive to water-conservative behaviour and sets a boundary at which plants substantially reduce leaf gas exchange. Hence, the WP curve could be used to select crop varieties able to endure longer periods of drought with minimal impact on carbon assimilation,and better manage irrigation based on estimates of Ψ pd to support effective use of water without a yield decrease.

A two-year field study was conducted to explore the influence of fertilizer sources on Zataria growth and quality characteristics. Treatments comprised control (no fertilizer), synthetic fertilizer, cow manure, vermicompost, and combinations of synthetic fertilizer with cow manure or vermicompost. Synthetic fertilizer was applied at 109kg ha-1 urea, 58kg ha-1 triple superphosphate, and 52kg ha-1 potassium sulfate (N50 P25 K25 ). Organic fertilizers were applied at 5tons ha-1 , and combined treatments comprised half rate of both organic and synthetic sources. The results indicated that young plants benefited from readily available nutrients released from synthetic fertilizer and produced 37% and 50% more biomass compared with sole cow manure and vermicompost, respectively. The highest biomass (167g m-2 ) and oil yield (3.63g m-2 ) were obtained from the combination of synthetic fertilizer and cow manure in established plants. The oil concentration of plants that received either cow manure or vermicompost were higher than synthetic fertilizer. Linalool was the dominant oxygenated monoterpene and represented 82% and 88% of the essential oil in 2023 and 2024, respectively, when cow manure was used. The findings of this research further substantiate the idea that Zataria represents a valuable source of antioxidant compounds, with potential for industrial exploitation.

Microalgae offer a simple and sustainable way to capture carbon dioxide (CO2 ) from industrial emissions while producing valuable biomass for fuels, feed and other bioproducts. In this review, we summarize recent progress in designing and improving closed-loop microalgae systems that capture CO2 and recycle nutrients and energy. We compare several industrial pilot projects around the world to show which designs work best at scale and highlight remaining hurdles. To organize these challenges, we introduce a Barrier-Impact Matrix that maps technical, economic and regulatory obstacles alongside potential solutions. Finally, we discuss how to get more value from the harvested biomass and how life cycle assessments (LCAs) can guide future improvements.

Complex trichomes in the leaves of epiphytic Bromeliaceae absorb water and nutrients, while also facilitating long distance water transport along the leaf surface, a phenomenon previously characterized for two Tillandsia species. This study aimed to determine trichome traits that govern external water transport speed, and its relation to life form, xylem transport capacity and environmental conditions. Using near-infrared optical techniques, we characterized trichome-mediated transport in 19 species and analyzed its association with trichome and vascular traits, functional group, and habitat parameters. External leaf water transport was observed in 10 species, all of which were atmospheric life forms (nebulophytes and pseudobulbs). Transport speed positively correlated with trichome area, wing length, and degree of overlap. Species with higher trichome overlap had lower xylem capacity (Kx ) and tracheid diameter and numbers, suggesting that the atmospheric life form is related to secure, inefficient vascular systems, which may be partly compensated with external transport. External transport was more common in species from habitats with high maximum vapor pressure deficits and low aridity indices, suggesting it enhances water uptake by rapidly redistributing water across available trichomes before evaporation can occur.

Aggravation of salinity is a world-wide concern and the applicability of ancient wheats towards tackling this concern has been neglected so far. This study aims to unravel the molecular-physiological basis of salt response in ancient emmer and spelt wheats. Effects of prolonged salt exposure (0, 75, and 150mM NaCl) on 18 modern and ancient tetraploid and hexaploid wheat genotypes were initially investigated in a pot experiment. Responses of a selection of four genotypes in a field experiment and expression of SOS1 and NHX1 ion-transporter genes in a hydroponic experiment were then assessed under 150mM NaCl. Salinity led to suppressions in relative water content (RWC), chlorophyll, carotenoids, K+ , grain yield, and biomass, though it increased Na+ , proline, H2 O2 , malondialdehyde, and activity of antioxidative enzymes. Accumulation of Na+ in the ancient emmer genotypes was substantial. But, emmer genotypes suffered less from salinity, as they maintained chlorophyll, biomass, and grain yield/plant. Emmer outranked durum, bread, and spelt wheats in terms of expression of SOS1 and NHX1 ion-transporter genes, confirming possession of an enhanced Na+ compartmentalization capability. These findings indicate that emmer wheat harbors an efficient molecular mechanism to tolerate salt and implies applicability in tackling salt stress damage to the wheat's grain yield.