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The inoculation response of single arbuscular mycorrhiza fungi (AMF) or rhizobia (Rh) in relation to nitrogen (N) acquisition of plants is well established, while the combined effect of both AMF and Rh is poorly known with regard to N assimilation for changes in amino acids of white clover (Trifolium repens). A pot study was carried out to evaluate the effect of single versus dual inoculation of AMF (Rhizophagus intraradices) and rhizobium (Rhizobium trifolii) on plant growth, leaf and root N contents, root amino acid contents, and root N-related enzyme activities in white clover. One hundred days after inoculations, Rh inoculation significantly stimulated the root colonization by R. intraradices. A single inoculation of AMF or Rh improved the plant growth (biomass production, root projected area, and root volume), root N acquisition, and dual inoculation of AMF and Rh further expanded some of these positive effects on root projected area and root N contents than single inoculation. All the inoculations notably increased activities of root asparagines synthase, nitrate reductase, and glutamate synthase, whilst dual inoculation displayed a much stronger effect in asparagine synthase activity than single inoculation. Single Rh treatment increased root glutamate and proline content, single AMF inoculation induced an increase in glutamate, aspartate, arginine, and ornithine content, while dual inoculation stimulated the accumulation of aspartate and proline. These results suggested the cooperation between the AMF and Rh inoculations, which magnified the positive effect on partly N metabolites and N-assimilation relevant enzymes of white clover.

The demand for ornamental plants is increasing due to urban greening and rural construction, while the growing environment of plants, especially the soil environment, is deteriorating. Hence, sustainable methods of ornamental plant cultivation need to be developed quickly. The application of arbuscular mycorrhizal fungi (AMF) to ornamental plants can be one of the eco-friendly ways to achieve the objective. Soil AMF establish mycorrhizal symbiosis with roots of ornamental plants, which can develop a marvelous mycorrhizal mycelium network in the rhizosphere to stimulate nutrient and water acquisition of host plants. Numerous researches have proven that AMF improved the quality of ornamental plants, like fruit yield, height, biomass, seed quality, the size and number of flowers, leaf, and root. In addition, mycorrhizal fungi also improve nutrient uptake and endogenous hormone balance of host plants. Another important function of AMF is to regulate the physiological, biochemical, and molecular responses of host plants to adversity, including drought stress, temperature stress, heavy-metal stress, and insect and disease stress. From the perspective of the ecological garden landscape, AMF richness would maintain plant abundance, nutrient and energy balance, and higher productivity in normal and soil environment stress, thus, establishing a friendly-environmental ecosystem. This review also provides the basis to exploit and improve the commercial application of AMF in ornamental plants in the future.

Citrus canker is a quarantined disease, severely harming citrus plants. Soil beneficial arbuscular mycorrhizal fungi (AMF) can provide a biological control pathway to resist pathogens. This work was to test changes of signal substances including hydrogen peroxide (H2O2), nitric oxide (NO), calmodulin (CaM), salicylic acid (SA) and jasmonic acid (JA) and the pathogen defense gene expression in roots of AMF (Paraglomus occultum) and non-AMF trifoliate orange (Poncirus trifoliata) seedlings after infected by a expressions citrus canker pathogen (Xanthomonas axonopodis pv. Citri, Xac). AMF inoculation significantly improved plant height, stem diameter and leaf number. Xac infection dramatically decreased root H2O2, NO, and SA levels, but increased root CaM and JA concentrations in non-AMF seedlings. There were higher H2O2 and CaM levels and lower JA levels in Xac-infected seedlings than in non-Xac-infected seedlings under mycorrhization. Under non-Xac infection, mycorrhizal treatment reduced root H2O2, NO, and SA but increased CaM and JA levels. However, under Xac infection, mycorrhizal inoculation distinctly accelerated root H2O2, NO, CaM, and SA accumulation, accompanied with up-regulated expression levels of root PtEPS1 (enhance pseudomonas susceptibility 1) and PtPR4 (pathogenesis related gene 4), indicating that Xac stimulated mycorrhizal roles in enhancing resistance of citrus canker. Such results imply that citrus plants with pre-inoculated AMF had stronger resistance to Xac infection through increasing signal substrate accumulation and pathogen defense gene expressions. ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

Beneficial fungi - including difficult - to - culture arbuscular mycorrhizal fungi (AMF) and the culturable endophytic fungus Piriformospora indica - play positive roles in hosts under controlled conditions, whereas information regarding the application of these fungi in field citrus (a mycorrhizal - dependent plant) is scarce. The present study aims to analyze the effects of two AMF species (Diversispora spurca and D. versiformis) and an endophytic fungus (P. indica) on the fruit quality and soil properties of Newhall navel oranges (Citrus sinensis Osbeck cv. Newhall) grafted on trifoliate oranges in the field. The results showed the improvement of root fungal colonization following fungal inoculation. The fungal inoculations increased the soil's acid, neutral, alkaline, and total phosphatase activity, as well as soil Bray-P content; increased the distribution of water-stable aggregates, mainly in the size range of 2–4 mm; and stimulated the production of easily extractable, difficultly extractable, and total glomalin-related soil proteins in a fungal-species-dependent manner, which was positively correlated with soil aggregate stability. Fungal inoculations, to some extent, improved external fruit quality, depending on the fungal species. Among the three fungi, only D. versiformis significantly increased the fruits' soluble solid content, but all three together promoted fruit glucose, fructose, and sucrose content. The two AMF species dramatically increased fruit phosphorus (P) content, while P. indica distinctly reduced it. D. versiformis also significantly elevated fruit potassium (K), magnesium (Mg), and manganese (Mn) content, D. spurca improved fruit copper (Cu), zinc (Zn), K, and Mg content, and P. indica increased fruit iron (Fe) and Zn content, compared with non-inoculated controls. Our results indicate that the field inoculation of citrus with AMF and P. indica partially improved fruit quality and soil properties, providing a pathway for P. indica to partially replace AMF in field citrus applications.

Poly(e-caprolactone) (PCL) composites filled by multi-walled carbon nanotubes (MWCNTs) which was non-covalently modified by the combined surfactants of poly(sodium 4-styrenesulfonate) and cetyltrim...

The aim of the present study was to analyze the effects of two arbuscular mycorrhizal fungi (AMF), Funneliformis mosseae and Paraglomus occultum, on leaf water status, root morphology, root sugar accumulation, root abscisic acid (ABA) levels, root malondialdehyde (MDA) content, and root antioxidant enzyme activities in white clover (Trifolium repens L.) exposed to well-watered (WW) and drought stress (DS) conditions. The results showed that root colonization by F. mosseae and P. occultum was significantly decreased by 7-week soil drought treatment. Under drought stress conditions, mycorrhizal fungal treatment considerably stimulated root total length, surface area and volume, as compared with non-mycorrhizal controls. In addition, inoculation with arbuscular mycorrhizal fungi also increased leaf relative water content and accelerated the accumulation of root glucose and fructose under drought stress. Mycorrhizal plants under drought stress registered higher activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) and ABA levels in roots, while lower MDA contents, relative to non-mycorrhizal plants. As a result, mycorrhiza-inoculated plants represented better physiological activities (e.g. antioxidant defense systems, root morphology, and sugar accumulation) than non-inoculated plants in response to soil drought, whilst P. occultum had superior effects than F. mosseae.

Monsanto’s Bt-cotton NC 33B, planted in northern China for more than one decade, effectively controls cotton bollworms; however the understanding of its potential effects on soil microorganisms is limited. The dynamics of eubacterial, fungal and actinomycetes population sizes in rhizosphere soil of the Bt cotton were analysed by realtime PCR (qPCR) at the different growth stages under field conditions during 2009 to 2011. Results showed that the population sizes (microbial rDNA gene copies) of eubacteria, fungi and actinomycetes in rhizosphere soil were markedly affected by natural variations in the environment related to the year, cotton growth and cultivar. However, there was no significant difference in eubacterial, fungal and actinomycetes population size in rhizosphere soil be tween the Bt-cotton NC 33B and its near-isogenic comparator DP 5415. In general, the Bt-cotton NC 33B did not show evident effects on the population sizes of eubacteria, fungi and actinomycetes in rhizosphere soil under field conditions after three-year cultivation.

Polymer composites of low-density polyethylene/polypropylene/ graphite/vanadium dioxide (LDPE0.8/PP0.2/Gr0.4/VO2) are prepared by classical melt-mixing technology and show a notable double positive temperature coefficient of electric resistivity (PTC), which originates from the combined effect of highly conductive Gr and VO2 with a thermal phase transition. When the weight ratio of VO2 is 8 wt %, the positive temperature coefficient intensity (PTCI) for the composites reaches 3.85 orders of magnitude. The model system demonstrates the reason for the improvement in the PTC performance of the polymer composites by analyzing the construction of the conductive networks. Therefore, the addition of phase-transition compounds may be a promising path to improving PTC materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 133, 44876.

Transgenic CrylAc and CpTI insect-resistant cotton SGK321 is widely adopted for many years in several regions of China, however the understanding of its potential effects on soil enzyme activities is not studied. The impacts of transgenic cotton SGK321 on dehydrogenase, urease and phosphatase activities in rhizosphere soil were investigated in a two-year field study in Northern China. Rhizosphere soil enzyme activities between transgenic cotton SGK321 and its non-transgenic parental cotton Shiyuan 321 were found to differ at senescence. However compared to the plant growth stages and cotton cultivar, the impacts of the transgenic trait were minor or transient. The principal component analysis also showed no significant or minor difference in the activities of dehydrogenase, urease and phosphatase in the rhizosphere soil of transgenic cotton SGK321 and its counterpart. Our results indicated that the transgenic cotton SGK321 has no apparent impact on dehydrogenase, urease and phosphatase activities in rhizosphere soil.

Transgenic CrylAc and CpTI insect-resistant cotton SGK321 has been widely adopted for many years in several regions of China, however the understanding of its potential effects on soil microorganisms is limited. The impact of transgenic cotton SGK321 on microorganism populations in rhizosphere soil was investigated. The numbers of bacteria, fungi, and actinomycetes were measured by counting colony-forming units after incubation on appropriate medium in a two-year field study in the northern China. Rhizosphere soil microorganism populations between transgenic cotton SGK321 and its non-transgenic parental cotton or conventional cotton were different at some plant growth stages and/or in some years. However compared to the plant growth stage and cotton cultivar, the impacts of the transgenic trait were slight or transient. The principal component analysis also showed no significant or minor difference in the numbers of bacteria, fungi, and actinomycetes in rhizosphere soil between transgenic cotton SGK321 and its non-transgenic parental cotton. These results suggest that the transgenic cotton SGK321 has no apparent impact on microorganism populations in rhizosphere soil.

Prepared a electrode with high concentration and strong active oxidizing property which used titanium as anode’s substrate material, used gradient method the anode surface was coated with a definite ratio RuO2、TiO2、IrO2、SnO2、Ga and Ce in order to extend the operational life span. Use scanning electron microscope to present the surface property, the result shows that the surface coat of self-made titanium positive plate is densification and well-distributed which has good catalytic activity and reaction stability, meanwhile the surface coated with metallic oxides has less and short cracks which can extend the useful life. Through the electrochemistry property detection by electrochemistry workstation, Tafel curve shows that the chlorine precipitation potential is 1.41V which is just a little higher than the standard potential 1.36v of Cl- reacting to form Cl2, meanwhile lower than the oxygen precipitation potential, these shows that the plate has good electro-catalysis property and selectivity. The self-made experimental setup includes four parts as direct supply, reactive tank, electrode, collecting bottle. Prepared solution with deionized water and analytical pure agents with NH4Cl and NaCl, with draining water method collecting the electro-catalysis gas and gas chromatographic analysis shows the main component includes N2 62.73%, O2 21.47%，H2 13.95%，Cl2 1.85%, meanwhile analysis the trends of nitrogen forms concentration, chloridion concentration and pH by electrolysis time, concluding that the indirect oxidation is dominant process during electrochemistry, active substrate OCl- is the principal oxidation. The electrolyte pH keeps range between 7.5 and 9.5 which is favorable to free ammonia forming that can be directly electrochemical oxidized, meanwhile is disadvantage of free chlorine forming that can keep cyclic utilization in solution.

In this paper, the relationships between landscape pattern and water quality at western reservoir area in Shenzhen City were studied with grey connection method, and the influences of source' and 'sink' landscape patterns on non-point pollution were probed. The results showed that the dominance, adjacency, and fragmentation of 'source' and 'sink' landscapes could markedly influence the water quality. From 2000 to 2001, due to the changes of the 'source' and 'sink' landscape patterns in research areas, the output of pollutants increased and the reduction of pollution decreased, resulting in the deterioration of water quality of three reservoirs. According to the spatial distribution of 'source' and 'sink' landscapes, it was found that the distribution of 'sink' landscapes at the middle-lower reaches of the watersheds had close relationships with the changes of reservoir water quality, suggesting that 'sink' landscape pattern was of significance in the management of non-point pollution.