Plant, Soil and Environment - In Press
Photosynthetic and related traits in variety-specific drought acclimation of soybeanOriginal Paper
Jiri Krucky, Vaclav Hejnak, Marek Popov, Jan Kubes, Jana Ceska, Lubomir Harencar, Milan Skalicky, Pavla Vachova, Frantisek Hnilicka
This study evaluated the acclimation of eight soybean varieties to water deficit through changes in photosynthetic performance and physiological, biochemical, and epigenetic traits. Plants were grown under controlled conditions in two treatments: control (80% water-holding capacity; WHC) and drought (40% WHC). Water status was assessed using relative water content and osmotic potential, while photosynthetic performance was evaluated using gas exchange, water use efficiency, maximum quantum efficiency of photosystem II, chlorophylls, and carotenoids. Total flavonoid content, reducing power, proline accumulation, and 5-methylcytosine content were determined. Water deficit induced marked variety-specific changes across traits. The varieties Hana and Atacama maintained higher RWC, less negative Ψₛ, and more favourable photosynthetic performance under drought, while the variety Atlas showed a favourable profile in several other traits. In contrast, the varieties Dornburg, York, and Impala showed a less favourable response, whereas the varieties Labrador and Zaria occupied intermediate positions depending on the trait evaluated. Multivariate and correlation analyses showed that photosynthetic performance was closely associated with plant water status, while stronger biochemical and epigenetic responses were more evident in less favourable or intermediate profiles. These results indicate that soybean acclimation to water deficit is coordinated and variety-specific and cannot be assessed using a single parameter.
The Effects of Post-anthesis Shading on Starch Granule Size Distribution and Viscosity Parameters in Waxy and Non-waxy Soft Wheat
jing LI, tingting Yang, ruilian Zhang, yang Liu, Rehman Abdul, Xiaomin Shang, Suhui Yan, wenyang Li
To explore the effects of post-anthesis weak light on grain yield and starch quality of waxy and non-waxy soft wheat (brewing wheat), a field experiment was conducted over the 2023–2025 growing seasons. Two cultivars were selected as test materials: Jinuo 2 (waxy soft wheat) and Quanmai 725 (non-waxy soft wheat). Four shading treatments with different intensities were applied after anthesis, including no shading (control), 10% shading, 20% shading, and 30% shading. The study focused on analyzing the impacts of varying post-anthesis shading degrees on yield, quality, starch granule size distribution, and pasting viscosity parameters of the two wheat types.The results showed that post-anthesis low light stress significantly reduced grain number per spike, thousand-grain weight, and grain yield of both cultivars, while markedly increasing their protein content, wet gluten content, and sedimentation value. Concurrently, the volume and surface area percentages of A-type starch granules (>10 μm) increased, whereas those of B-type starch granules (≤10 μm) decreased with increasing shading intensity. Under the same shading treatment, Jinuo 2 exhibited higher volume and surface area distribution percentages of B-type starch granules but lower percentages of A-type starch granules compared with Quanmai 725.With the enhancement of shading intensity, key pasting viscosity parameters of wheat grain starch—including peak viscosity, trough viscosity, final viscosity, breakdown value, and setback value—all showed a decreasing trend. Notably, Quanmai 725 had higher values for all these viscosity parameters than Jinuo 2. Additionally, low light stress reduced starch gelatinization temperatures (onset, peak, and conclusion temperatures) while increasing gelatinization enthalpy in both cultivars. Specifically, Quanmai 725 had higher gelatinization temperatures than Jinuo 2, whereas Jinuo 2 displayed a higher gelatinization enthalpy.Correlation analysis revealed that the volume distribution of B-type starch granules (≤10 μm) was significantly positively correlated with peak viscosity, trough viscosity, final viscosity, breakdown value, and setback value. In contrast, the volume distribution of A-type starch granules (>10 μm) showed a significantly negative correlation with these viscosity parameters.In conclusion, post-anthesis weak light impairs yield and reduces the proportion of B-type starch granules while increasing the proportion of A-type starch granules in both waxy and non-waxy soft wheat. It also significantly decreases key viscosity parameters (peak viscosity, trough viscosity, final viscosity) and increases gelatinization enthalpy. Compared with Quanmai 725 (non-waxy soft wheat), Jinuo 2 (waxy soft wheat) is more sensitive to post-anthesis low light in terms of starch granule distribution.
Proline-Mediated Drought Tolerance Promotes Essential Oil Yield and Menthol-Rich Composition in Peppermint Through Integrated Physiological RegulationOriginal Paper
Abeer Elhakem, Amira Hassan
This study investigated the impact of foliar proline (Pro 10 mmol/L) and four levels of water field capacity (WFC 95, 75, 50, and 25%) on peppermint (Mentha piperita L.) using a factorial pot experiment with two treatment factors. A decrease in WFC gradually reduced shoot growth, relative water content, and total chlorophyll, and increased osmolytes, antioxidant activity, and abscisic acid (ABA), whilst decreasing indoleacetic acid (IAA) and gibberellins. Essential oil (EO) yield showed a biphasic response: increases of 13.9% and 16.7% at 75% and 50% WFC, and a decrease of 30.6% at 25% WFC compared to relative control plants. Foliar Pro improved 24 of 26 measured variables and showed additive effects at all drought levels for 23 of 26 variables. WFC × Pro interactions were significant only for ABA (P = 0.001), Na⁺ content (P = 0.040), and the Na⁺/K⁺ ratio (P = 0.046); for all three, the effect of Pro was proportionally bigger under severe drought, demonstrating that ABA signalling and Na⁺ homeostasis are subject to modulation by Pro in a drought-severity-dependent manner. Pro reduced the EO yield penalty at severe drought to only 5.6 %, increased menthol, and decreased menthone and pulegone. Together, these results show that foliar Pro enhances peppermint drought tolerance mainly via additive physiological improvements rather than through collateral effects on other sap constituents; the modulation of ABA and Na⁺ at different severities of drought stress may be pluridimensional secondary responses but are mechanistically distinct.
Synergistic effects of magnesium fertilization and machine-transplanting density improve rice yield and grain qualityOriginal Paper
Ran Wang, Lubing Jia, Jianming Ding, Keyuan Zhang, Xiaotian Jiang, Rongping Zhang, Yan Lan, Peng Ma
To clarify the regulatory mechanisms and optimal combinations of magnesium fertilizer application rates and planting density on rice yield, quality, and magnesium uptake and utilization in the hilly regions of Sichuan. This study utilized a two-factor split-plot design in field trials conducted from 2024 to 2025. The main plot was magnesium application rate, with four treatments: 0 kg/ha (Mg0), 30 kg/ha (Mg1), 45 kg/ha (Mg2), and 60 kg/ha (Mg3). with the secondary factor being planting density, comprising three treatments: 14 cm×30 cm (D1), 18 cm×30 cm (D2), and 22 cm×30 cm (D3). The study investigated the effects of magnesium fertilizer application rates and planting density interactions on rice yield components, leaf physiological characteristics, dry matter transport, and magnesium fertilizer use efficiency. The results showed that compared with the Mg0 treatment, the Mg3 treatment significantly increased rice yield, with the best results observed in combination with the D1 treatment, yielding a 14.52% increase compared to the Mg0 treatment. Dry matter transport in rice increased significantly with magnesium fertilizer application. Compared to the Mg0 treatment, the Mg3 treatment increased stem and leaf dry matter transport by 19.64%, and post-heading dry matter transport by 30.76%; The D1 treatment further optimized dry matter transport. Compared to the D3 treatment, the amount of stem and leaf dry matter transport, the transport rate, and the contribution rate to grain increased by 26.44%, 34.28%, and 40.32%, respectively. Magnesium uptake and utilization efficiency was highest under the Mg3 treatment. Compared to the Mg0 treatment, magnesium uptake and utilization efficiency increased by 31.25%, and the physiological utilization rate of magnesium fertilizer increased by 24.71%; under the D1 treatment, the agronomic utilization rate and uptake and utilization efficiency of magnesium fertilizer increased by 38.22% and 20.20%, respectively, compared to the D3 treatment. Furthermore, the Mg3D1 treatment significantly increased the rice leaf area index and chlorophyll content, while simultaneously improving rice processing and appearance quality and reducing chalkiness and amylose content. This series of measures achieved synergistic optimization of magnesium fertilizer application rates and planting density.
Effects of Cadmium on the ASA-GSH Cycle and Antioxidant Compounds in Different Ecotypes of Perennial RyegrassOriginal Paper
Junlong Wang, Li Cao, Jinhuan Yi, Kai Zhou, Guilian Shan, Na Jiang
Cadmium (Cd) is a common heavy metal contaminant in agricultural soils; its high bioaccumulation potential and toxicity mean it enters the human body via the food chain, posing a health risk. Perennial ryegrass (Lolium perenne L.) is renowned for its high tolerance to heavy metal toxicity and is frequently used in phytoremediation. This study examined growth morphology, activities of ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione peroxidase (GPX), and glutathione reductase (GR), as well as non-enzymatic antioxidant contents in two perennial ryegrass cultivars: ‘WNS’ (low Cd accumulation) and ‘YY’ (high Cd accumulation), under Cd treatments of 0, 3, 6, and 12 mg/kg Cd2+. Under Cd stress, ‘WNS’ exhibited significantly higher plant height, leaf length, tiller number, GPX activity, and glutathione (GSH) content compared with ‘YY’. At 12 mg/kg Cd, GR activity in ‘WNS’ was also significantly higher than in ‘YY’ (P < 0.05). In contrast, at each Cd level, ‘YY’ showed significantly higher leaf Cd accumulation, APX and DHAR activities, and ascorbic acid (ASA) content than ‘WNS’ (P < 0.05), accompanied by elevated oxidized glutathione (GSSG) content. The comprehensive response index of ‘YY’ under 3, 6, and 12 mg/kg Cd was 2.77, 2.91, and 2.94 times that of ‘WNS’, respectively. In summary,‘WNS’ mitigates Cd toxicity and maintains growth homeostasis by sustaining higher levels of GPX and GR activity, as well as GSH content. This study provides a theoretical basis for elucidating differential Cd tolerance mechanisms between ryegrass cultivars with contrasting Cd accumulation capacities, and offers insights for refining phytoremediation strategies in Cd-contaminated soils.
Bacterial Cellulose in Sustainable Agriculture: Bibliometric Map and Critical Review of Agronomic Applications and Waste-Valorised ProductionReview
Vidya Muddappa Shimoga, Ellen Ruth Hunga, Elson Hunga, Bukkambudhi Krishnaswamy Manjunatha, Chandrika Tantry, S Divya
Bacterial cellulose (BC) is a lignin-free nanofibrillar hydrogel with high water-binding capacity, mechanical strength, and biodegradability. Despite these properties, a Scopus bibliometric survey of 738 publications (2015–2025) showed that agricultural applications accounted for only 17% of BC research, while biomedical and materials-science applications dominated. This review contributes a bibliometric quantification of that imbalance; a four-function synthesis of BC as a cultivation substrate, soil amendment, seed or biological carrier, and agrochemical platform; and a production route–property–application matrix linking waste feedstocks to agronomic functions. Direct crop evidence remains limited. In a controlled tomato-seedling study, 0.01% BC increased substrate water-holding capacity by up to 14% and improved survival, root development, and nutrient availability under restricted irrigation. Supporting evidence from plant-derived cellulose and other biopolymer hydrogels demonstrates improved germination and soil-moisture regulation, but should not be interpreted as direct BC validation. Feedstock selection affects production cost, material properties, and application fit simultaneously. Multi-season field trials, matched comparisons with commercial substrates and hydrogels, standardised characterisation, and life-cycle and techno-economic assessments remain priorities.