Plant-environment interactions (Hoboken, N.J.)最新文献

High-altitude wetlands of the Andes (HAWA) are unique ecosystems influenced by substrate conditions and reliant on consistent water supply from precipitation, runoff, groundwater, and glacial melting. Considering the diverse ecosystem services provided by HAWAs and the increasing threat these ecosystems face from natural and anthropogenic factors, such as drought, land-use change, and climate change, it is crucial to conduct a comprehensive assessment of their vulnerability. In this study, we characterized the functional trait spectrum of dominant plant species within the Salar de Pedernales, Quebrada Leoncito (Leoncito) and Río Negro HAWAs and explored the relationships between these traits and key environmental variables. Our results revealed significant variation in plant species based on traits such as leaf dry matter content (LDMC), specific leaf area (SLA), relative water content (%RWC), and leaf thickness. Species were primarily differentiated by LDMC and SLA. Plants from Salar de Pedernales had higher δ13C values, indicating higher water-use efficiency (WUE) compared to those in tributaries like Leoncito and Río Negro. A positive correlation between stomatal conductance and CO₂ assimilation was found, with the Salar de Pedernales plants showing high WUE despite these plants exhibiting similar photosynthetic rates. Foliar nitrogen percentage and δ¹⁵N values indicated nitrogen availability could be influenced by microbial activity and salinity levels. Higher salinity in the Salar de Pedernales may inhibit microbial activity, resulting in higher δ¹⁵N values. At the community level, decreased SLA correlated with higher δ¹³C values, suggesting less carbon discrimination and higher WUE in the Salar de Pedernales plants. While HAWA plant species have adapted to their environment, their limited dehydration tolerance makes them vulnerable to future hydrological changes. Understanding these responses forms a basis to develop effective conservation and management strategies for HAWAs.

This preliminary study aimed to investigate the mitigation effect of silicon (Si) on field dodder-induced stress in sugar beet. The experiment was conducted as a completely randomized design with three factors, including parasitic infection (non-parasitized and dodder-parasitized sugar beet), Si source (5 mM Si in the form of Na₂SiO₃ or K₂SiO₃), and Si application method (control, seed pretreatment, irrigation, and foliar spraying). Without Si, field dodder caused a 44.9% reduction in shoot biomass and a 57.5% reduction in root biomass. Although pretreating seeds with Si solutions accelerated emergence, it did not significantly influence any other traits measured in the sugar beet. Sugar beets that received Si through irrigation exhibited better protection against field dodder than those that were sprayed; furthermore, K₂SiO₃ proved to be more effective than Na₂SiO₃. Irrigating or spraying sugar beet with K₂SiO₃ reduced field dodder biomass by 60%-65%, while the reduction ranged from 20% to 35% with Na₂SiO₃. The highest lignin content was observed by watering and spraying dodder-parasitized sugar beet with K₂SiO₃, resulting in a 4.2-fold increase through watering and a 3.8-fold increase through spraying. Field dodder infection led to increased activity of enzymes involved in scavenging reactive oxygen species, including catalase, guaiacol peroxidase, superoxide dismutase, and lipoxygenase in sugar beet. The application of Si further increased the activities of superoxide dismutase and lipoxygenase. This preliminary study suggests that irrigating with K₂SiO₃ can help reduce damage caused by field dodder in sugar beet. However, additional research is necessary to evaluate the crop's response at the field level.

The use of high plant density tolerant maize hybrids was one of the most successful interventions that boosted maize yield in the developed world. However, very little research has been conducted in the improvement of maize for high plant density tolerance in West and Central Africa (WCA). This study aimed to identify high plant density-tolerant maize hybrids adapted to multiple environments. Forty-eight maize hybrids were evaluated under three plant densities (low = 53,333, medium = 66,666, and high = 88, 888 plants ha^-1). The experiment was conducted in four different environments in Ghana using 8 × 6 alpha lattice design with split plot arrangement. Plant density was the main plot and hybrids arranged in incomplete blocks within each plant density. The results revealed that the relative grain yield performance of the genotypes was dependent on plant density. Optimum plant density for the hybrids varied with growing environments. The highest grain yield of 9.5, 9.2, and 8.6 t ha^-1 were obtained from the high plant density in Legon (minor season), Fumesua, and Legon (off-season), respectively, and it was 26.7%, 22.7%, and 30% increase in comparison to the respective yield under the low density. F₁ hybrids M131 × CML16, CML16 × TZEI1, CML16 × 87,036, TZEI387 × CML16, and ENT11 × 87,036 are good candidates for high-density planting in high-yielding environments. Grain yield performance of the maize hybrids was highest under high plant density for most of the growing environments. Thus, implementing high-density planting for maize hybrids could be one of the options for increasing maize yield in West and Central Africa.

Melatonin, a multifunctional, non-toxic regulatory molecule, plays a crucial role in enhancing tolerance to abiotic stress, which is tightly linked to S metabolism. Despite the proven efficacy of sulfur (S) in enhancing abiotic stress tolerance, the combined effect of S and melatonin in stress mitigation remains to be elucidated. This is particularly relevant in the context of climate change, where the increased occurrence of waterlogging stress increases the risk of reduced S availability, leading to reduced yield and quality in rapeseed. The objective of this study is to examine the impact of a combination of foliar melatonin and sulfur, when administered to soil or leaves, on the response of plants to waterlogging stress. The experimental design involved the supplementation of rapeseed (Brassica napus L.) plants with sulfur (S) to either the soil (0.2 g kg^-1) or the leaves (300 ppm) 5 days prior to stress induction. The plants were subjected to waterlogging at BBCH-31 for a period of 7 days, preceded by a pretreatment 2 days prior to the stress with melatonin (200 μM). In comparison, untreated plants subjected to waterlogging showed a significant reduction in growth, nutrient uptake, photosynthetic activity, and sugar content but an increase in the antioxidant defense system. However, the application of melatonin significantly mitigated the adverse effects of waterlogging stress. In comparison with the control, soil-S application exhibited higher efficacy than foliar S application in increasing plant resistance, as reflected by improved dry weight (+50%), photosynthesis (+12%), stomatal conductance (+40%), sulfur (+40%), magnesium (+59%), and reduced hydrogen peroxide (-22%) and lipid peroxidase (-26%). This combination also increased antioxidant defense by increasing catalase (+43%), glutathione reductase (+17%), ascorbate peroxidase (+47%), ascorbate (+39%), and glutathione (+40%) contents, in contrast to untreated waterlogged plants. The study underlines the potential of melatonin and sulfur as effective agents to alleviate waterlogging stress.

Rumex alpinus L. (R. alpinus) is a non-native invasive plant in Czech mountain regions, altering ecosystem structure and function in protected areas. Rumex obtusifolius L. (R. obtusifolius) is a native species and a problematic weed in Czech meadows, while Rumex longifolius DC. (R. longifolius) is characteristic of Fennoscandia and widespread in northern and central Europe. This study explores temperature-driven germination patterns in R. alpinus, R. obtusifolius, and R. longifolius and also focuses on potential differences across populations of R. alpinus. The hypothesis suggests that R. alpinus is not established in lowland areas due to temperature limitations during germination. A second experiment evaluates the influence of native and non-native localities on R. alpinus seed germination. The primary experiment was conducted at 6°C, 12°C, 18°C, 24°C, 29°C, and 35°C in a climate chamber, while the second experiment was performed at 24°C for 14 days. Contrary to expectations, R. alpinus exhibited the highest germination rate across all temperatures. In the second experiment, germination rates varied significantly, with a positive correlation between germination success and transition from Alpine to Czech localities. The highest and fastest germination was observed in seeds from the Krkonoše Mountains, where R. alpinus is an invasive plant species.

The effect of artificial light at night (ALAN) on plants is a less explored area within light pollution research. This is especially true for the physiological parameters of photosynthesis of woody plants. The physiological and morphological values of nineteen deciduous urban tree species illuminated by street lamps with a color temperature of 3000 K were examined for light-polluted and non-light-polluted leaves. The morphological studies covered leaf macromorphology (leaf length, leaf width, and biomass production) and histological development (height of the dorsal epidermis and palisade parenchyma, width of photosynthesizing ground tissue and the leaf). The fluorescence yield of the photochemical system II and the net photosynthesis and transpiration of the leaves exposed to different light conditions were determined in the photosynthetic physiology studies. The species included in the research react differently to artificial light, some are able to utilize the extra lighting at night, while others are negatively affected. In this way, the species can be grouped according to their sensitivity to light pollution. The impact of street lights on vegetation can be easily detected by the combined treatment of micromorphological and photosynthetic physiology tests, macromorphological values are not suitable parameters.

In 2016, a National Academies of Sciences, Engineering, and Medicine advisory committee proposed omics technologies as one possible adequate response to the regulatory challenges posed by gene editing and synthetic biology. This paper presents a set of questions that would need to be answered to integrate omics experiments and data into crop regulatory systems. These questions concern both experimental practice and how omics-experimental and regulatory systems intersect. We anticipate that the chosen answers to these questions will impact the scientific validity, regulatory burden, and usefulness for forecasting risk in nuanced ways. In doing so, we conclude that the integration of omics technologies into regulatory systems poses an array of more-than-technical dilemmas whose management will require cross-sector collaboration and innovative approaches to socio-technical decision-making.

Intercropping enhances plant growth, increases yield, and boosts the accumulation of secondary metabolites. Platycodon grandiflorus (P. grandiflorus), a traditional Chinese medicinal herb, has limited research available regarding its intercropping practices. We aimed to (1) examine the changes in the physiological and biochemical indicators of plant growth during the intercropping process of P. grandiflorus, (2) assess the quality of P. grandiflorus when intercropped with different crops, and (3) evaluate the optimal intercropping mode for P. grandiflorus. This study utilized the two-year seedlings of P. grandiflorus as the test material in a field study. The intercropping treatments included P. grandiflorus monoculture (JG-JG), intercropping with Achyranthes bidentata (JG-NX), Saposhnikovia divaricata (JG-FF), Adenophora stricta (JG-SS), Zea mays (JG-YM), Setaria italica (JG-GZ), and Glycine max (JG-DD). We investigated the effects of these different intercropping modes on the growth, physiological and biochemical indicators, and the accumulation of five saponins in P. grandiflorus at various growth and development stages. Compared with JG-JG, the chlorophyll and the MDA contents significantly increased and decreased, respectively, in the JG-YM, JG-DD, and JG-NX treatments. All the three treatments enhanced the biomass and exhibited the higher levels of antioxidant enzyme activity and osmoregulatory substance content. JG-YM and JG-SS significantly (p < 0.05) improved the quality of P. grandiflorus, with JG-SS intercropping notably maintaining a high content of platycodin D. The results of this study provide a scientific basis for optimizing intercropping planting systems and advancing the sustainable development of the traditional Chinese medicine industry.

Over millions of years of interactions, plants have developed complex defense mechanisms to counteract diverse insect herbivory strategies. These defenses encompass morphological, biochemical, and molecular adaptations that mitigate the impacts of herbivore attacks. Physical barriers, such as spines, trichomes, and cuticle layers, deter herbivores, while biochemical defenses include the production of secondary metabolites and volatile organic compounds (VOCs). The initial step in the plant's defense involves sensing mechanical damage and chemical cues, including herbivore oral secretions and herbivore-induced VOCs. This triggers changes in plasma membrane potential driven by ion fluxes across plant cell membranes, activating complex signal transduction pathways. Key hormonal mediators, such as jasmonic acid, salicylic acid, and ethylene, orchestrate downstream defense responses, including VOC release and secondary metabolites biosynthesis. This review provides a comprehensive analysis of plant responses to herbivory, emphasizing early and late defense mechanisms, encompassing physical barriers, signal transduction cascades, secondary metabolites synthesis, phytohormone signaling, and epigenetic regulation.

In Senegal, the average rice consumed is 100 kg per capita per year. The objective was to evaluate and select the well-adapted high-yielding lines in Ndiaye and Fanaye growth conditions in Senegal River Valley. One hundred and twelve advanced lines were evaluated in consecutive wet and dry seasons at AfricaRice Fanaye and Ndiaye sites challenged by drought and high temperatures. Unlike Fanaye, Ndiaye faces severe water scarcity and extreme heat. An alpha-lattice design was used with three replications. The number of tillers and plant height at 30 days after sowing, plant height at maturity, days to 50% heading, and grain yield; physiological: leaves chlorophyll content at 50% heading stage, yield grain, thousand grain weight, and number of panicles per plant were recorded to evaluate the increasing of rice productivity. Results showed significant variation among the advanced lines and the test "Kruskal-Wallis medians" was used for the mean comparison for the five descriptors during growth and development stages. Path analysis revealed that Ndiaye's harsh conditions negatively impacted NT30, PH30, PHmat, PNP, Dmat, and GY, with negative effects on NT30 (ρ = -0.63), PH30 (ρ = -0.67), and PNP (ρ = -0.15). However, SH (ρ = 0.71) and TGW (ρ = 0.37) had positive direct effects. Cluster analysis generated four groups showing the characteristics of 112 advanced lines. Most of the advanced lines were outperforming local elite varieties. The lines WAC 18-WAT15-3-1, WAC 18-WAT65-1-1, WAC 13-WAT32-2-1, and WAB 2150-TGR1-WAT3-1 produced the highest yields for Ndiaye, with 4752, 5589, 5589, 5644, and 6943 kg/ha. For Fanaye, the best genotypes were IR 09 N523, CT18919-4-2-2-2SR-1P, CT18494-4-4-3-3-1SR, WAB 2125-WACB-1-TGR1-WAT1-1, and CT19541-13-3-1-2P-3P, with 8824, 8984, 9014, 9639, and 8496 kg/ha, respectively. The authors recommend that these lines be released or used as donors in breeding programs, and further studies can consider stability analysis using the best adapted varieties.