Acta Physiologiae Plantarum最新文献

Bletilla striata is a perennial herb of the orchid family with its tubers frequently used in medicine, food, chemistry, and cosmetics industries. Polysaccharide, total phenolic, and militarine are the main bioactive components of B. striata that have been widely used for the treatment of hematemesis, hemoptysis, and traumatic bleeding due to the efficacy of arresting bleeding with astringent action. As the yield and quality of medicinal materials are closely related to the harvest time, it is of great significance to choose the optimal harvest time of B. striata. In the present study, effects of four different harvest times of 2-year-old B. striata were compared based on their morphological characteristics and bioactive compounds contents. The results showed that the fresh weight and drying rate of B. striata showed non-significant difference among four different harvest times. However, the content of B. striata polysaccharide (BSP) was firstly decreased and then gradually stabilized with the delaying of the harvest time. The contents of total phenolic and militarine in the B. striata harvested on Sep. 23 were the highest. Under the comprehensive consideration of B. striata quality and yield, the results indicated that it is more reasonable to harvest B. striata in late September.

Calcium ions (Ca²⁺) are absorbed from the soil by the root cells before being distributed throughout the plant. The transport of Ca²⁺ to aboveground parts relies on the movement of xylem, which is influenced by the transpiration rate of individual organs. The final distribution of Ca²⁺ in tissues and cells depends on the effective function of channels and transporters that facilitate Ca²⁺ movement through plasma and specific intracellular membranes. Local fluctuations in free Ca²⁺ concentrations serve as a mechanism to elicit cellular responses, characterized by distinct calcium signatures, or to enable long-distance signaling in a cell-to-cell network. The specificity of individual Ca²⁺ transport proteins is primarily determined through studies in plants with induced changes in the expression of these proteins. Concurrently, it is recognized that plant cells contain significant reserves of Ca²⁺ both in the labile and in the permanently bound states, which influences various aspects such as biomechanical properties or the defensive capabilities of the cells. The diverse roles of Ca²⁺ in plant cells highlight the importance of a thorough understanding of Ca²⁺ metabolism.

Ovate family proteins (OFPs) are plant-specific, transcriptional repressors characterized by an OVATE domain. The OFP family has been analyzed only from a handful and functionally characterized from even fewer species. There is a gap in cataloging the complete compendium of OFP family across Gramineae although the complete genome sequence for several species are now available. In the present study, we identified and cataloged homologs of OFPs across ten Gramineae members to analyze gene and protein structure and properties, evolutionary relationship, expression pattern, and predict interacting partners. A positive correlation was found between genome-size and OFP family size, with Triticum genome harboring the maximum number; most of the Gramineae OFPs are intronless. Comparative analysis revealed variation in gene sizes, physico-chemical properties of proteins, and their structures including motifs. Phylogenetic reconstruction reflected homolog-based clustering. Expression analysis in Oryza revealed spatio-temporal variation with maximum expression in reproductive tissues. Prediction of interactome showed homeobox domain containing proteins as major interacting partners. The study thus form foundation for future functional analysis of role of OFPs in regulating economically important traits.

Pea is the third most widely grown leguminous vegetable crop globally. The crop is fairly easy to grow but is salt and drought-sensitive, limiting its yield. This study aimed to explore the morphological and biochemical responses of peas under salt stress and water-deficit stress. Three pea varieties (Climax, Green grass, Meteor) were subjected to different levels [5.4 mM (Control), 50 mM, 75 mM, and 100 mM of NaCl] of salt stress. The water-deficit stress was administered by watering 100%, 75%, and 50% of field capacity. Morphological parameters showed a significant reduction under salt and water-deficit stresses in all three varieties. The highest relative water content under various levels of both stresses was 38.3% which was significantly lower than the control treatment. Chlorophyll content index (CCI) declined significantly in all three varieties, however, Climax exhibited a noteworthy CCI of 43.7 at 100 mM salt treatment, significantly higher than Green grass (25.9 CCI) and Meteor (35.9 CCI) at the same treatment. Significant accumulation of proline content was observed under both stresses, where 100 g of fresh weight of Climax showed proline content as 0.043 mg against 100 mM salt and 0.040 mg against 50% water-deficit treatments. Similar trends were recorded for water-deficit stress, indicating a shared response to both stress types. These findings provide insights into the effects of salt and water-deficit stress on pea crops, specifically focusing on the role of proline. The insights gained may aid in developing strategies to mitigate these stresses for enhanced pea crop productivity.

Many phenolics are known to possess allelopathic activity, but the allelopathic effect of pyrogallol has not been previously reported. Here, the present experiment was conducted to investigate the effects of commercially obtained pyrogallol at different concentrations on the seed germination and seedling growth of L. perenne. The results showed that (1) Pyrogallol treatment inhibited L. perenne seed germination, as evidenced by a decrease in the final germination rate and a delay in germination peaks. (2) Pyrogallol treatment reduced L. perenne plumule length, radicle length, fine root length, and fine root surface area, higher pyrogallol concentrations reduced the proportion of fine roots. (3) Higher concentrations (2.00 g/L) of pyrogallol resulted in decreased protein content and increased membrane lipid peroxidation. (4) Spraying pyrogallol inhibited the growth of L. perenne seedlings, as manifested by a decrease in plant height and biomass. Overall, our findings indicate that pyrogallol is one of the allelochemicals present in aqueous extracts of K. integrifoliola leaves that inhibits the seed germination and seedling growth of L. perenne.

Cucumber is an important vegetable crop that suffers from significant yield loss because of sub-optimal temperatures during the growing season. High temperature affects the plant's health and reduces the quality and quantity of the final harvest. Huge diversity in terms of different economically important traits, including wide temperature adaptation, is recorded in indigenous cucumber germplasm because of its Indian origin. It is necessary to identify the key traits and genotypes with the contrasting response from a large set of germplasm associated with heat stress response for understanding the physio-biochemical and molecular network associated with heat tolerance. A set of 123 germplasm was evaluated in a growth chamber with temperature stress treatment (40 °C/35 °C) for two subsequent seasons. Besides, 10 selected genotypes based on their response in the seedling stage were grown under natural field conditions with high temperatures to validate the physio-biochemical response in the seedling stage and yield parameters in the reproductive stage. Among the different parameters, slow degradation of chlorophyll, higher anti-oxidant enzyme activity, higher membrane stability index, and higher canopy temperature depression were identified as key traits explaining the heat stress response in cucumbers. Besides, the photosynthetic activities of the tolerant genotypes at the reproductive stage were also higher under field conditions, resulting in higher economic yield. Heat tolerance index was developed for 123 genotypes for seven physiological traits recorded in the present study. The optimised screening technique in the seedling stage and their validation for yield response under natural field facilitated the evaluation of a large number of genotypes for use in breeding for heat stress tolerance in cucumbers. Besides, the identified germplasm, WBC-13, DGC-103 and DARL-106 with effective heat stress tolerance will be instrumental in understanding the molecular basis of heat tolerance and designing climate-smart cucumber cultivars.

This work aimed to evaluate how the C3-CAM shift could contribute to photoprotection and attenuate losses of CO₂ uptake in Pereskia aculeata plants under water stress. Plants were subjected to treatments: well-watered (WW), water deficit (WD), and recovery (Rec) in two experimental conditions (greenhouse and growth chamber). Induction of the C3-CAM shift by drought was assessed by leaf acidification, carbohydrate content, photochemical activity, gas exchange, and stomata density and closure during diurnal and nocturnal periods. Leaf acidity was reduced during the night period in WW-plants and increased in WD-plants, suggesting active accumulation of organic acids associated with CAM induction by drought. This apparent CAM induction in WD-plants was associated to increase carbohydrates and significant reduction of leaf water potential (Ψ_W). WD-plants showed a positive carbon balance associated with a higher net-CO₂ uptake (P_N) during night period compared to WW-plants. Moreover, WW-plants presented negative values for P_N associated with a negative carbon balance at night. In both conditions (WW and WD) plants showed P_N near zero at night. However, a positive carbon balance associated with a slight stomatal aperture at during the day and strong closure during night in the WD-plants, suggests that C3-CAM shift, able to maintain CO₂ uptake, presented a better trend toward the CAM-cycling model. Together, this study shows that CO₂ uptake conferred by C3-CAM shift under drought contributed to photoprotection and better photosynthetic recovery after rehydration of Pereskia aculeata plants.

Wheat, a glycophyte plant that is the main staple food for the majority of the world’s population, is considerably sensitive to salinity and alkalinity stress. The goal of this study was to investigate antioxidant enzyme activity and elemental analyses to determine the response of three wheat genotypes to alkaline stress during the early development period as well as to examine DNA damage caused by alkaline stress using the inter simple sequence repeats (ISSR) molecular markers. The results demonstrated that NaHCO₃ treatments affected the amount and ratio of Na and K in all genotypes’ roots and leaves. Furthermore, NaHCO₃ treatment had a significant impact on H₂O₂ contents and malondialdehyde (MDA) levels of genotypes which exhibited varying abilities to reduce reactive oxygen species-induced damage and stress severity affected enzymatic antioxidant systems (SOD, CAT, and POD activities). The ISSR results revealed that genomic template stability rates decreased in response to alkaline stress. Overall, the data revealed significant genotype by alkaline salt exposure interaction, indicating that genetic response to alkaline salt stress may be different with respect to cultivars. In our study, cv. Çetinel 2000 had more enzymatic and non-enzymatic activity compared to cv. Aytin-98 and Tir genotypes under concentrations NaHCO₃ concentration, while latter two genotypes varied responses under the different concentrations. Our research also showed that genetic variability does exist in wheat for alkaline salt tolerant/resistant genes, further research using transcriptomic techniques is required to establish the gene expression profiles of wheat genotypes under such stress conditions to assess the genetic information about the related genes.

This paper presents data on the seed germination ecophysiology of three Arabis species endemic to Cyprus: Arabis cypria, Arabis kennedyae and Arabis purpurea. Final seed germination in the dark, as a function of temperature, presented different responses among species and among seed lots of the same species. Different degrees of seed dormancy were also identified among different seed lots. In all cases, maximum final germination was achieved between 10–20 °C. Red light irradiation is the most efficient treatment for dormancy breakage in all three species, which implies phytochrome control of seed germination. As a result, seed germination in nature is expected to take place on the soil surface and not under canopy cover. The small seed size, the light requirement for germination and the variable germination patterns among different seed lots of the three studied species imply the formation of soil seed banks, perhaps as an essential part of their survival strategy. The value of the data presented in this paper is discussed in relation to the ex-situ conservation of the studied species.

Soil salinization limits the crop yield. Strigolactone GR24 is a plant growth regulator regulating environmental responses and enables the plant to tolerate stress by modulating morphology and physiology. Ajwain is a medicinal crop as well as a seed spice. The current experiment was designed to inspect the possible potential of GR24 as seed priming in mitigating the disastrous consequences of salinity in ajwain. Two ajwain populations, one from University of Agriculture, Faisalabad and the other from Peshawar were used for this study. Pre-sowing seed treatments (0, water-soaked, 0.001, 0.01, and 0.1 mg/L GR24) were given for 3 h. Salt stress at 100 mM NaCl was applied after 77 days of seed sowing. Salt stress reduced the yield and disturbed the distribution of ions in ajwain plants. The GR24 seed priming inhibited shoot Na⁺ uptake (33.81%), increased Ca²⁺ uptake and use efficiency (71.41%, 37.24%), K⁺ uptake and use efficiency (72.13%, 31.25%) and yield parameters including umbels/plant (31.22%), total seed weight (165%), and total number of seeds per plant (16.45%). Faisalabad population exhibited more umbels per plant and 1000 seed weight while Peshawar population accumulated less shoot Na⁺. Of different levels used for seed soaking, GR24 at 0.1 mg/L more effectively enabled the plant to adjust with elevated salt levels in the soil.