Simple Summary: To reduce the influence of chemical fertilizers and pesticides on the cultivation of Fritillaria taipaiensis P. Y. Li, this study adopted the application of microbial fertilizer to mitigate soil damage and enhance the plant's stress resistance. In this experiment, the growth index, enzyme activity, and gene expression of F. taipaiensis leaves were measured by applying nitrogen-fixing bacteria. The results showed that nitrogen-fixing bacteria could promote the growth and development of F. taipaiensis. This study not only provides a theoretical foundation for the subsequent cultivation technology of F. taipaiensis but also provides a new idea in terms of the realization of green planting of Chinese medicinal materials. The widespread application of chemical fertilizers and pesticides has resulted in environmental pollution. With the growing emphasis on ecological agriculture in traditional Chinese medicine, microbial fertilizers are increasingly recognized for their potential. The aim of this study is to investigate the effect of inoculating nitrogen-fixing bacteria on the soil (yellow loam, river sand, and organic fertilizer in a 2:1:1 ratio) of Fritillaria taipaiensis, with a focus on the leaf changes in terms of physiological parameters, antioxidant enzyme activity, and corresponding gene expression levels. The experiment involved three nitrogen-fixing bacteria, namely Rahnella aquatilis, Pseudomonas chlororaphis, and Paenibacillus stellifer, with a total of eight treatment groups. The objective was to assess how these bacterial treatments influenced physiological parameters, photosynthetic characteristics, pigment content, and both antioxidant enzyme activities and gene expression in the leaves of F. taipaiensis. The experimental results demonstrated statistically significant reductions (p < 0.05) in malondialdehyde (MDA) content and stomatal limitation value (LS) in F. taipaiensis leaves under treatment conditions relative to the control group (CK). The most substantial decreases were observed dual-inoculation with R. aquatilis and P. stellifer (N5), showing reductions of 38.24% and 20.94% in MDA and LS compared to CK values. Additionally, leaf area, leaf thickness, stem thickness, plant height, photosynthetic parameters, pigment content, soluble sugars, soluble proteins, proline levels, and the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) exhibited varying degrees of increase. Compared to the CK group, the SOD, POD, and CAT activities of the N5 group increased by 141.06%, 160.59%, and 106.23%, respectively. The relative gene expression patterns of SOD, POD, and CAT corresponded with the trends observed in their respective antioxidant enzyme activities. Pearson correlation analysis further demonstrated that leaf area and net photosynthetic rate (Pn) were significantly correlated with respect to SOD, POD, and CAT activities, as well as their corresponding gene expression levels. In conclusion, inoculation with nitrogen-fixing bacteria improved the growth and stress tolerance of F. taipaiensis, with the combined application of Rahnella aquatilis and Pseudomonas stellifer yielding the most effective results. This study establishes that different rhizosphere nitrogen-fixing bacteria, either individually or in combination, influence the photosynthetic characteristics, physiological and biochemical parameters, and protective enzyme systems of F. taipaiensis. These findings provide a theoretical foundation for the selection of nitrogen-fixing bacteria as biofertilizers in the artificial cultivation of F. taipaiensis and highlight their potential application in the cultivation of traditional Chinese medicinal materials.

The study aimed to determine how the physiological responses of the sunflower (Helianthus annuus L.) plant were affected by prolonged drought stress, salinity stress, and boron application, as well as to assess the recovery dynamics following re-watering. The experimental design included well-watered (WW 80% watering), drought stress (DS, 20% watering) salinity stress (SS, 0 control and 13 dS m-1), boron toxicity (Na2O5B2O3.10H2O, at different doses of 0 and 8 mg L-1) and re-watering after a long-term period of drought stress (24 days). The well-irrigated (80% WW) treatment, which included all factors as a the non-stressed control treatment during the experiment was carried out with five replications. Morphological, physiological and biochemical analyses of plants were measured at four time points: at the 10th and 24th days after the onset of the drought stress period and after re-watering, at 2nd and 7th days following. The relative membrane permeability was increased and relative water content was decreased because drought and salinity stress limited water availability and caused an imbalance in the water status of the leaves and stem of the plant. Even though high levels of Na+ and Cl- ions interfered with essential nutrient uptake under drought stress and boron application, Ca+2 ion levels in the leaves significantly increased in the leaves of plants in areas treated with drought, salt, and boron after re-watering. Extended or intense drought and salinity conditions harmed the phloem and xylem tissue cells of the stem by changing cell size and density, which in turn disrupted biochemical processes, including the functioning of water channels under challenging circumstances. Particularly under conditions of salt and drought stress, the vascular bundles in the plant stem were observed to either shrink significantly or assume an irregular shape. Long-term drought reduced relative water content (RWC) values, resulting in plant dehydration and increased osmotic pressure (RMP) in leaf cells, further exacerbated by salinity and drought stress. The plant attempted to regain some of its characteristics in response to these severe stress conditions after re-watering. However, 24 days after the long dry period, even if watering was re-applied, the growth power of the plant was reduced due to the disturbance in membrane permeability as a result of excessive cell damage.

Drought is one of the most severe environmental stresses affecting soybean growth and development, especially in arid and semi-arid areas. The aim of this experiment is to evaluate the effect of regulated deficit irrigation during the vegetative stages on soybean plants and determine the amount irrigation water can be reduced without affecting the physiological parameters, the crop phenology, and the yield of the soybean crop. The field experiments were conducted during two irrigation crop seasons (2021 and 2022) in Louata, Morocco. The results showed that regulated deficit irrigation regimes during the vegetative stages was combined with high temperatures and low air humidities during the beginning of flowering and the pod filling stage during 2021 in comparison with 2022, especially for 25% CWR (crop water requirements). Regulated deficit irrigation regimes reduced the stomatal conductance by 46% and 52% respectively during the first and second growing seasons by limiting CO2 intake for the Calvin cycle. The stomata closure increased the leaf temperature and affected the functioning of the photosynthetic apparatus by damaging the chlorophyll pigments and impairment of electron transport chains in chloroplasts. The transition from regulated deficit irrigation to 100% CWR at the beginning of flowering (R1) compensated for the photosynthetic loss, improved the growth and development of soybean plants and enhanced the yield and its components for 50% and 75% CWR. The adaptative mechanism such as the remobilization of the carbon reserved in the stems and leaves (vegetative tissues) to the grains improved the grain yield by 36.7% during 2021 and by 32.2% during 2022 and. This consequently improved the water use efficiency, the water productivity of soybean for 50% and 75% CWR and contributed to water saving with an average of 60 mm per growing season. (c) 2024 Crop Science Society of China and Institute of Crop Science, CAAS. Production and hosting by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC- ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Rice is threatened by ineffective inputs of water and fertilizers. Therefore, we detected the effect of soil clay content on plant physiological traits and their relationships to phosphorus (P) utilization -efficiency of rice under different irrigation options. Thus, our experiment was conducted in a two -factor randomized complete block design. The first factor was irrigation method, including three choices: alternate wetting/critical drying (AWCD) (50% drying), alternate wetting/sharp drying (AWSD) (30% drying), and alternative wetting/minor drying (AWMD), (10% drying). The second factor was soil clay amount, with three levels at 65, 50, and 30%, corresponding to SHC, SMC, and SLC. The root 's growth and activity were lower in AWCD x SLC than in AWMD x SHC. While the former treatment decreased the P content in soil, the latter increased their availability. The glutamine synthetase (492.5 mu mol g -1 h -1 ) was lower in AWCD x SLC than in AWMD x SHC at 1006.1 mu mol g -1 h -1 , leading to the increase of oxidative cell damage. The optimal P nutrition improved plant growth under AWMD x SHC. The AWCD x SLC led to the minimum agronomic efficiency of P (PAE, 13.67 g/g) and the apparent recovery efficiency of P (PARE, 1.55%). However, the maximum values of PAE (44.05 g/g) and PARE (21.45%) were detected in AWMD x SHC. This study suggests that increasing soil clay content encourages the growth, yield, and P uptake of rice under alternate wetting/minor drying irrigation. The study has excellent application potential, providing technical support for precision water and P fertilizer management of rice.

Simple Summary Hybrid rice often has higher yields than comparable inbred varieties. However, hybrids are sometimes more susceptible to insect herbivores. Outbreeding can improve herbivore resistance in hybrids compared to one (a condition called heterosis) or both (called heterobeltiosis) of their parental lines. The frequency of heterosis for resistance has not been assessed under varying soil nitrogen conditions. Nitrogen is predicted to reduce a plant's ability to resist herbivores but increases its ability to compensate for damage, known as tolerance. We examined the resistance and tolerance of eight hybrids and their parental lines to herbivores by exposing plants to the brown planthopper, whitebacked planthopper or yellow stemborer and observing herbivore fitness responses (i.e., resistance) and herbivore-induced changes to plant biomass (i.e., tolerance). There were no consistent trends in relative resistance or tolerance to the herbivores across plant types; however, improved resistance and tolerance were frequently associated with the male parent. Nitrogen reduced resistance and generally increased tolerance to herbivores irrespective of plant type. Across the eight hybrids, relative resistance and relative tolerance were not determined by heterosis or heterobeltiosis. Our results highlight the difficulties in predicting the outcomes of crossing to achieve relatively resistant hybrids.Abstract Hybrid rice results from crossing a male-sterile line (the A line) with a pollen doner (the restorer or R line). In 3-line hybrid breeding systems, a fertile B line is also required to maintain A line populations. Heterosis is defined as a condition of traits whereby the hybrid exceeds the average of the parental lines. Heterobeltiosis is where the hybrid exceeds both parents. Hybrid rice may display heterosis/heterobeltiosis for growth, yield and resistance to herbivores, among other traits. In a greenhouse experiment, we assessed the frequency of heterosis for resistance to the brown planthopper (Nilaparvata lugans (BPH)), whitebacked planthopper (Sogatella furcifera (WBPH)) and yellow stemborer (Scirpophaga incertulas (YSB)) in eight hybrids under varying soil nitrogen conditions. We also assessed plant biomass losses due to herbivore feeding as an approximation of tolerance (the plant's capacity to compensate for damage). Nitrogen reduced resistance to all three herbivores but was also associated with tolerance to WBPH and YSB based on improved plant survival, growth and/or yields. Plant biomass losses per unit weight of WBPH also declined under high nitrogen conditions for a number of hybrids, and there were several cases of overcompensation in rice for attacks by this herbivore. There was one case of nitrogen-related tolerance to BPH (increased grain yield) for a hybrid line with relatively high resistance, likely due to quantitative traits. Heterosis and heterobeltiosis were not essential to produce relatively high herbivore resistance or tolerance across hybrids.

Acacia origena , a member of the Leguminosae family, thrives in the challenging A environmental conditions of southwestern Saudi Arabia and holds significant economic value. However, the recent occurrence of forest fires has posed a considerable threat to this species, prompting a comprehensive exploration of its resilience. This study investigates the impact of forest fires on Acacia origena , a resilient species in southwestern Saudi Arabia, with a focus on wood anatomy, soil chemical characteristics, and associated microorganisms in Al Mofareh Mountain, Alsoudah, southwestern Saudi Arabia. Fifteen samples from burned and unburned areas were analyzed. These samples were sectioned in both transverse and tangential planes to facilitate light microscopy and the analysis of wood anatomy, revealing distinctive coloration and structural changes in burned tissues. Larger-diameter specimens demonstrated greater resilience, accumulating tannins and forming tyloses to insulate damaged areas. Soil analysis indicated post-fire alterations in texture, composition, and nutrient levels. Microbial assessments highlighted varying responses in yeast and total germ colonies, it was increased by 75%. These findings provide valuable insights into the ecological responses of A. origena and soil ecosystems to fire, emphasizing the importance of comprehensive studies to guide conservation and management efforts in fire-affected regions .

In soil, chromium can be found in two main valence forms: hexavalent Cr (VI) and trivalent Cr (III). In terms of toxicity, the most toxic form to plants is Cr (VI). In the present study, we investigated the impact of Cr (VI) (0, 25, 50, 75 and 100 ppm) on growth, physiological parameters and the translocation kinetics of Cr (VI) in the faba bean plant (Vicia faba L.). The results showed that Cr (VI) negatively affects growth parameters (- 15% to - 72%), tolerance index (- 34.05% to - 64.7%), and reduce the total chlorophyll content (until 40%) compared to control plants without Cr (VI). However, the increase of Cr (VI) concentration in the soil, stimulated the synthesis of sugars (max 6,97 mg/g FM), proteins (max 62.89 mu g/mg FM) and proline (max 98.57 mu g/mg FM) and increased the electrolyte leakage (+ 2.5% to + 9%) compared to control plants. Cr (VI) concentrations in shoots and roots increased significantly for all Cr (VI) doses applied. The translocation factor results showed that the majority of the Cr (VI) absorbed by the plant is stored in the roots, with a very low bioaccumulation factor, which does not exceed 0.4. The findings show that Cr (VI) negatively affects the morpho-physiological parameters of Vicia faba, the bioaccumulation of organic solutes and the low bioaccumulation factor of Cr (VI) can be considered as a strategy of tolerance to Cr(V).

Lettuce (Lactuca sativa L.) is the most consumed leafy vegetable in Brazil. It is cultivated using at least four distinct systems, the most common of which are conventional and hydroponic systems. These systems provide different cultivation conditions for plants, causing physiological changes that are important for commercial production, such as nutrient uptake and biomass accumulation. However, only a few studies have compared the physiological aspects of these two cultivation systems. The objective of this study was to evaluate the physiological behavior of 'Rubinela' lettuce plants grown in hydroponic and conventional pot systems, by comparing dry mass (DM) and fresh mass (FM) production, number of leaves (NF), stomatal density, and contents of chlorophyll, carotenoids, anthocyanin, sugars, and starch. Plants cultivated in hydroponic systems presented significant differences in chlorophyll content, producing more biomass than plants cultivated in conventional pot systems, probably because of better nutritional conditions, primarily with respect to macronutrients, provided by the nutrient solution of the hydroponic system. The lower water availability encountered by plants cultivated in conventional pot systems influenced the increased sugar and starch concentrations, as well as the anthocyanin content, which may be a strategy to mitigate the possible damage caused by hydric stress conditions.

Increases in the atmospheric concentration of carbon dioxide and associated changes in climate may exert large impacts on plant physiology and the density of vegetation cover. These may in turn provide feedbacks on climate through a modification of surface-atmosphere fluxes of energy and moisture. This paper uses asynchronously coupled models of global vegetation and climate to examine the responses of potential vegetation to different aspects of a doubled-CO2 environmental change, and compares the feedbacks on near-surface temperature arising from physiological and structural components of the vegetation response. Stomatal conductance reduces in response to the higher CO2 concentration, but rising temperatures and a redistribution of precipitation also exert significant impacts on this property as well as leading to major changes in potential vegetation structure. Overall, physiological responses act to enhance the warming near the surface, but in many areas this is offset by increases in leaf area resulting from greater precipitation and higher temperatures. Interactions with seasonal snow cover result in a positive feedback on winter warming in the boreal forest regions.