The duality of sulfate-reducing bacteria: Reducing methylmercury production in rhizosphere but enhancing accumulation in rice plants.

Sulfate-reducing bacteria (SRB) are known to alter methylmercury (MeHg) production in paddy soil, but the effect of SRB on MeHg dynamics in rhizosphere and rice plants remains to be fully elucidated. The present study investigated the impact of SRB on MeHg levels in unsterilized and γ-sterilized mercury-polluted paddy soils, with the aim to close this knowledge gap. Results showed that the presence of SRB reduced MeHg production by ∼22 % and ∼17 % in the two soils, but elevated MeHg contents by approximately 55 % and 99 % in rice grains, respectively.

Physiological responses of low- and high-cadmium accumulating Robinia pseudoacacia-rhizobium symbioses to cadmium stress.

The role of rhizobia in alleviating cadmium (Cd) stress in woody legumes is still unclear. Therefore, two types of black locust (Robinia pseudoacacia L.) with high and low Cd accumulation abilities were selected from 11 genotypes in China, and the effects of rhizobium (Mesorhizobium huakuii GP1T11) inoculation on the growth, CO and HO gas exchange parameters, Cd accumulation, and the absorption of mineral elements of the high (SX) and low Cd-accumulator (HB) were compared.

Allelopathic effects of Eucalyptus extract and wood vinegar on germination and sprouting of rapeseed (Brassica rapa L.).

Eucalyptus plantations are usually characterized by low biodiversity due to allelopathy effects. Wood vinegar is considered a complex growth regulator that can promote plant growth at low concentrations. However, there is information scarcity about the co-application of eucalypt leaf water extract and wood vinegar on plants.

Biochar application improves karstic lime soil physicochemical properties and enzymes activity and enhances sweet tea seedlings physiological performance.

Karst lime soil, commonly found in rocky desert ecosystems of Southwest China, exhibits high pH, poor water retention, and intense erosion. To prevent further soil erosion and soil losses from these ecosystems, stabilization measures based on improved green infrastructure are needed. The present study aimed at elucidating the performance of sweet tea (Lithocarpus polystachyus) seedlings grown on this soil type upon biochar application.

Differences in aluminum tolerance and immobilization between two indigenous ectomycorrhizal fungi Lactarius deliciosus and Pisolithus tinctorius from Southwest China's forest stands.

Aluminum (Al) toxicity severely decreases plant growth and productivity in acidic soil globally. Ectomycorrhizal (ECM) fungi can promote host plant's Al-tolerance by acting as a physical barrier or bio-filter. However, little information is available on the role of ECM fungus on Al immobilization with respect to Al-tolerance.

Elevated CO and soil mercury stress affect photosynthetic characteristics and mercury accumulation of rice.

This is a novel study about responses of leaf photosynthetic traits and plant mercury (Hg) accumulation of rice grown in Hg polluted soils to elevated CO (ECO). The aim of this study was to provide basic information on the acclimation capacity of photosynthesis and Hg accumulation in rice grown in Hg polluted soil under ECO at day, night, and full day. For this purpose, we analyzed leaf photosynthetic traits of rice at flowering and grain filling.

Ethylenediurea (EDU) effects on Japanese larch: an one growing season experiment with simulated regenerating communities and a four growing season application to individual saplings.

Japanese larch ( (Lamb.) Carr.) and its hybrid are economically important coniferous trees widely grown in the Northern Hemisphere.

Effects of simulated nitrogen deposition on ectomycorrhizae community structure in hybrid larch and its parents grown in volcanic ash soil: The role of phosphorous.

With the rapid industrial development and modern agricultural practices, increasing nitrogen (N) deposition can cause nutrient imbalance in immature volcanic ash soil commonly found in Japan. Larch species, widely distributed in northeast Eurasia, are associated with ectomycorrhizal (ECM) fungi which play a critical role in nutrient acquisition for their hosts. In this study, we investigated species richness and diversity of ECM fungi associated with a hybrid larch (F) and its parents, Dahurian larch (Larix gmelinii var.

[Effects of Different Altitudes on Soil Microbial PLFA and Enzyme Activity in Two Kinds of Forests].

The soil microbial community is an important part in soil ecosystem, and it is sensitive to the ecological environment. Phospholipid-derived fatty acids ( PLFA ) analysis was used to examine variations in soil microbial community diversity and its influencing factors. The results showed that: there existed 48 PLFAs that were significant in the soil samples from six altitudes.

Ectomycorrhizal colonization and growth of the hybrid larch F₁ under elevated CO₂ and O₃.

We studied the colonization of ectomycorrhizal fungi and species abundance of a hybrid larch (F1) under elevated CO₂ and O₃. Two-year-old seedlings were planted in an Open-Top-Chamber system with treatments: Control (O3 < 6 nmol/mol), O₃ (60 nmol/mol), CO₂ (600 μmol/mol), and CO2 + O₃. After two growing seasons, ectomycorrhiza (ECM) colonization and root biomass increased under elevated CO₂.

Photosynthetic response of early and late leaves of white birch (Betula platyphylla var. japonica) grown under free-air ozone exposure.

Betula platyphylla var. japonica (white birch) has heterophyllous leaves (i.e.

Photosynthetic traits of Siebold's beech and oak saplings grown under free air ozone exposure in northern Japan.

We set up a free-air ozone (O(3)) exposure system for determining the photosynthetic responses of Siebold's beech (Fagus crenata) and oak (Quercus mongolica var. crispula) to O(3) under field conditions. Ten-year-old saplings of beech and oak were exposed to an elevated O(3) concentration (60 nmol mol(-1)) during daytime from 6 August to 11 November 2011.