Biotic interactions involving exotic plants in their introduced ranges may differ from those of co‐occurring plant species and from interactions in their native ranges. When interactions are less negative, or more positive compared to native plant species, this may increase invasion success, and differences among ranges may cause changes in exotic plant traits. Here, we investigated arbuscular mycorrhizae (AM) associated with Triadica sebifera seedlings from populations in native (China) and introduced ranges (US) and with seedlings from US and China species within three co‐occurring genera (Liquidambar, Ulmus, Celtis) grown in multiple common gardens in both ranges. No general pattern of higher or lower AM colonization was found in the introduced range for China and US Celtis, Liquidambar, or Ulmus species. However, AM colonization was significantly higher for Triadica than for other genera, particularly in the introduced range, suggesting AM may improve Triadica's invasion success. Triadica AM colonization was higher in US than China gardens, decreased with increasing soil nitrogen in China, but was independent of soil nitrogen in the US. This might reflect a different effect of soil fertility on this mutualism among ranges. Introduced Triadica populations had higher AM colonization than native populations, particularly in US gardens, implying a possible advantage from greater AM association in the introduced range. This is the first field study demonstrating post‐introduction changes in mycorrhizal colonization of an invasive species. It indicates that there are ecological and evolutionary components to the effect of positive interactions on plant invasions.

Whether global changes impact native and exotic species differently is unclear, because the changes may favour both native and exotic species over competitors. Previous studies have mainly focused on the separate effects of different environmental changes, but plant communities are influenced by the changes in multiple environmental factors, and it is still unclear whether native and exotic species respond similar to the combined effects of these factors. We hypothesized that differences in interspecific trade‐offs between native and exotic species can lead to the dominance of exotic species when the species are simultaneously subjected to multiple environmental changes. Using coastal saltmarsh plant communities as the study system, we experimentally manipulated flooding and nutrient enrichment, examined the interspecific trade‐offs between competitiveness and stress tolerance for two native and one exotic species, and explored the combined effect of the two environmental changes on both native–native and native–exotic species interactions. We found that flooding and nutrient enrichment oppositely affected native–native species interactions but additively affected native–exotic species interactions. The two factors together resulted in no net change in the relative advantages between the two native species but enhanced the dominance of the exotic species over the native species. This disparity occurred because the exotic species was not subject to the interspecific trade‐off between competitiveness and stress tolerance that constrained the native species. Synthesis. Our results suggest that changes in multiple environmental factors favour exotic species because of evolutionary novel trade‐off patterns. Mechanisms underlying species coexistence in the invaded community such as interspecific trade‐offs need to be considered when future attempts are made to predict the effects of global changes on biological invasions.

Under global warming, shifts in phenological synchrony between insects and host plants (i.e., changes in the relative timing of the interaction) may reduce resource availability to specialist insects. Some specialists, however, can flexibly track the shifts in host-plant phenology, allowing them to obtain sufficient resources and therefore to benefit from rising temperatures. Here, we investigated the effects of experimental warming on the life history of an invasive, specialist lace bug (Corythucha ciliata) and on the leaf expansion of its host plant (Platanus × acerifolia) in two spring seasons under field conditions in Shanghai, China. We found that a 2 °C increase in mean air temperature advanced the timing of the expansion of host leaves and of the activities of overwintering adult insects in both years but did not disrupt their synchrony. Warming also directly increased the reproduction of overwintering adults and enhanced the development and survival of their offspring. These results indicate that C. ciliata can well track the earlier emergence of available resources in response to springtime warming. Such plasticity, combined with the direct effects of rising temperatures, may increase the insect’s population size and outbreak potential in eastern China under climate warming.

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1. Coastal wetlands are large reservoirs of soil carbon (C) and have been invaded globally by the exotic species Spartina alterniflora. However, the effects of these invasions on soil C content remain unclear.2. We performed a meta-analysis of 2479 soil organic C (SOC) content observations collected from 91 field studies conducted in coastal China, the world's largest introduced range for S. alterniflora.3. Spartina alterniflora invasions had no significant effect on the SOC content in vegetated native wetlands in coastal China. S. alterniflora increased the SOC content in the top 30 cm of salt marshes after invading only one of the nine marsh types, which was dominated by a dwarf succulent species, Suaeda salsa in the northern subtropics and decreased the SOC content in the top 60 cm of mangroves dominated by Kandelia obovata and mixed communities after invasion in the southern subtropics. S. alterniflora invasions did not significantly affect the SOC content in the other salt marsh or mangrove ecosystems. Moreover, the SOC content in S. alterniflora-invaded ecosystems increased only on a decadal scale and then decreased, rather than increasing monotonically. 4. Synthesis and applications. Our findings reveal that the SOC content of S. alterniflora-invaded ecosystems is similar to or lower than that of most native ecosystems. As soil bulk density is often reduced by S. alterniflora invasions, the C storage capabilities of vegetated native ecosystems might be substantially reduced after S. alterniflora invasions. Moreover, the SOC content in these invaded ecosystems gradually decreased after long-term S. alterniflora invasions (>20 years). Therefore, the displacement of native salt marsh or mangrove species by S. alterniflora may not be considered a natural climate solution to increase the C sink in coastal China. Future efforts are required to control S. alterniflora preferentially in coastal wetlands where S. alterniflora invasions do not increase

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Summary Protective efficiency of a combination of four recombinant Brucella abortus (B. abortus) proteins, namely, ribosomal protein L7/L12, outer membrane protein (OMP) 22, OMP25 and OMP31, was evaluated as a combined subunit vaccine (CSV) against B. abortus infection in RAW 264.7 cell line and murine model. Four proteins were cloned, expressed and purified, and their immunocompetence was analysed. BALB/c mice were immunized subcutaneously with single subunit vaccines (SSVs) or CSV. Cellular and humoral immune responses were determined by ELISA. Results of immunoreactivity showed that these four recombinant proteins reacted with Brucella‐positive serum individually but not with Brucella‐negative serum. A massive production of IFN‐γ and IL‐2 but low degree of IL‐10 was observed in mice immunized with SSVs or CSV. In addition, the titres of IgG2a were heightened compared with IgG1 in SSV‐ or CSV‐immunized mice, which indicated that SSVs and CSV induced a typical T‐helper‐1‐dominated immune response in vivo. Further investigation of the CSV showed a superior protective effect in mice against brucellosis. The protection level induced by CSV was significantly higher than that induced by SSVs, which was not significantly different compared with a group immunized with RB51. Collectively, these antigens of Brucella could be potential candidates to develop subunit vaccines, and the CSV used in this study could be a potential candidate therapy for the prevention of brucellosis.

China is a rapidly developing country with the largest share of the world's population. The extent of human activity, combined with diverse climates and landscapes, may allow for greater risk of biological invasions. To date, at least 529 invasive species have been identified, including 270 species of higher plants, 198 species of animals and 61 species of microbes, resulting in an estimated annual economic loss of US$18.9 billion. Evidence to date suggests that different components of climate change (i.e. temperature, altered precipitation, extreme weather events and rising CO2 concentration) have already influenced the biology of invasive species in China. The influence of climate change may increase the negative economic or environmental consequences of some invasives; however, others may become disadvantaged. Although we are still at the earliest stages of understanding the consequences of climate change on invasive species biology, China is one of the countries that may be affected most dramatically by invasive species. Overall, understanding the interactions between climate change and invasive species biology is an important scientific challenge, but one in which Chinese scientists can make significant contributions. The inclusion of the invasive species issue in some of China's ongoing projects on global change could begin to address critical research needs in this area.