Do Native Parasitic Plants Cause More Damage to Exotic Invasive Hosts Than Native Non-Invasive Hosts? An Implication for Biocontrol

Field studies have shown that native, parasitic plants grow vigorously on invasive plants and can cause more damage to invasive plants than native plants. However, no empirical test has been conducted and the mechanism is still unknown. We conducted a completely randomized greenhouse experiment using 3 congeneric pairs of exotic, invasive and native, non-invasive herbaceous plant species to quantify the damage caused by parasitic plants to hosts and its correlation with the hosts' growth rate and resource use efficiency. The biomass of the parasitic plants on exotic, invasive hosts was significantly higher than on congeneric native, non-invasive hosts. Parasites caused more damage to exotic, invasive hosts than to congeneric, native, non-invasive hosts. The damage caused by parasites to hosts was significantly positively correlated with the biomass of parasitic plants. The damage of parasites to hosts was significantly positively correlated with the relative growth rate and the resource use efficiency of its host plants. It may be the mechanism by which parasitic plants grow more vigorously on invasive hosts and cause more damage to exotic, invasive hosts than to native, non-invasive hosts. These results suggest a potential biological control effect of native, parasitic plants on invasive species by reducing the dominance of invasive species in the invaded community

Interactive Effects of Arbuscular Mycorrhizal Fungi and Copper Stress on Flowering Phenology and Reproduction of Elsholtzia splendens.

Plant responses to heavy metal contamination may depend on the presence of arbuscular mycorrhizal fungi (AMF). Elsholtzia splendens is an indicator species for the presence of copper (Cu) mines because both its flowering phenology and reproduction are tolerant to heavy metals. To test whether effects of Cu on the flowering phenology and reproduction of E. splendens depend on the presence of AMF, we conducted a factorial experiment with two Cu treatments (with or without Cu addition) crossed with two AMF treatments (with or without AMF inoculation). Without AMF, Cu addition significantly delayed the onset dates, ending dates and peak dates of flowering and decreased flowering duration. However, AMF inoculation reversed the effects of Cu stress, with recovered flowering onset and ending dates and increased the flowering duration. Cu addition significantly decreased inflorescence width and number, inflorescence biomass, vegetative biomass and total seed number, but significantly increased 1000-seed weight. AMF inoculation significantly increased vegetative biomass. Two-way ANOVA results showed that the interactive effects between Cu addition and AMF inoculation were significant on the inflorescence number, vegetative biomass and total seed number. These results indicate that AMF can alleviate the Cu stress on the flowering phenology and reproduction of E. splendens

Optimal Layout and Overheat Monitoring for Components of Highly Reliable Relay Protection Equipment

Effective thermal management measures are of great significance for improving the reliability of relay protection equipment. Firstly, the paper establishes a temperature calculation function for components based on the thermal superposition model, calculates the minimum heat dissipation distance between components, and converts the functional coordination of components into coordinate constraints. An optimised layout scheme for components is obtained quickly based on the minimum heat dissipation distance and coordinate constraints. The finite element simulation results show that the optimized layout significantly improves the temperature of the components, with a maximum temperature reduction of 8.6%. Then a component overheating warning strategy is proposed based on state recognition. The life-accelerated decay ratio of the components is calculated by monitoring the operating temperature, and the allowable operating time and alarm signal of the components at a specific temperature are combined to reflect the components’ status accurately

Hotspot Temperature Prediction of Relay Protection Equipment Based on a Physical-Model-Aided Data-Driven Method

Relay protection equipment (RPE) is a type of automation equipment aiming to protect power systems from further damage caused by local faults. It is thus important to ensure the normal operation of RPE. As the power density of electronic components continuously increases, the overheating problem of RPE cannot be neglected. Given the difficulties in implementing direct measurement and predicting development trends of RPE temperature, a novel hotspot temperature monitoring method for RPE was proposed, which is a data-driven method. The generative adversarial network, aided by a physical model, is used to address small samples. Afterwards, a stacked ensemble model established based on random forests was used to predict the hotspot temperature of the RPE. Experiment results show that the proposed method can effectively predict hotspot temperature of RPE with the predictive error lower than 2%. And comparative results demonstrate the superiority of the proposed method compared to other methods

Photosynthesis, Nitrogen Allocation, Non-Structural Carbohydrate Allocation, and C:N:P Stoichiometry of <i>Ulmus elongata</i> Seedlings Exposed to Different Light Intensities

The leaf photosynthetic capacity, leaf N partitioning, non-structural carbohydrate content, C, N, and P contents of endangered U. elongata seedlings exposed to different light intensities were compared in this study. The most favorable light condition for the survival and growth of U. elongata seedlings in the present study was 100% full sunlight, as this induced higher Pn, PNUE, PC, PR, PB, and NSC content relative to shade-treated seedlings. PNUE, PR, PC, and PB in U. elongata seedling leaves decreased under 40% and 10% full sunlight, while PL increased, indicating that shade increased the light capture efficiency of photosystem (PS) II but decreased electron transfer from PSII to PSI. Furthermore, leaf N content increased with shade intensity, revealing an adaptive strategy for poor light environments. Additionally, the smallest leaf biomass, Pn, WUE, and CE values and C:N and C:P ratios in stems and leaves were observed under 10% full sunlight. These results indicate that seedlings growing under 40% full sunlight will benefit U. elongata conservation

Effects of Cu addition and AMF inoculation on the biomass of flowers (a), seeds (b), and vegetative tissues (c).

<p>-Cu-AMF indicates no AMF and no Cu, +Cu-AMF indicates Cu addition, -Cu+AMF indicates AMF inoculation, +Cu+AMF indicates Cu addition and AMF inoculation.</p

Mean flowering amplitudes for <i>E</i>. <i>splendens</i> under different treatments.

<p>Census intervals were 2 days. Amplitude shown is the mean number of flowers per day. -Cu-AMF indicates no AMF and no Cu, +Cu-AMF indicates Cu addition, -Cu+AMF indicates AMF inoculation, +Cu+AMF indicates Cu addition and AMF inoculation.</p

Correlation between the deleterious effect of parasites on hosts and the relative growth rate (RGR) of host with parasite (a) and without parasite (b), parasitism response of RGR of hosts (c).

<p>Pearson correlation coefficient (<i>r</i>) and <i>p</i>-values are given and values in bold are statistically significant at <i>p</i><0.05.</p

Salinity-induced changes in the rhizosphere microbiome improve salt tolerance of Hibiscus hamabo

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