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In order to find a more efficient, economical, and environmentally friendly chemical fertilizer alternative, we have developed a new type of microbial fertilizer. The reported types of functional microorganisms in biofertilizers are mostly single and concentrated in nitrogen-fixing bacteria and phosphate-solubilizing bacteria. Here we evaluate the effect of the compound microbial fertilizer with several kinds of functional bacteria. A field experiment was conducted with five treatments (no-fertilization control, regular fertilization 600 kg ha −1 , compound microbial fertilizer 750 kg ha −1 , compound microbial fertilizer 900 kg ha −1 , compound microbial fertilizer 1050 kg ha −1). The effects of the compound microbial fertilizer on wheat traits, grain yield, soil physical and chemical properties, and microbial community structure were investigated. The results showed that the compound microbial fertilizer as base fertilizer could not only enhance the contents of soil available phosphorus and available potassium but also enhance the grain yield markedly. The compound microbial fertilizer could affect the microbial community, and the change of the microbial community was more correlated with growth period of wheat. The results established that the compound microbial fertilizer which can reduce part of the amount of chemical fertilizer can enhance wheat yield and the recommended dose of the fertilizer is 750 kg ha −1 in the study area.

RNAi technology, known as a revolutionary technology in the history of pesticides, has been identified as a very promising novel approach for crop protection, which is of great significance for achieving the sustainable agricultural development of the United Nations Food and Agriculture Organization. Although many studies have shown that RNA biopesticides have strong application prospects, its stability seriously restricts the commercial use. As the core component of RNAi, double-stranded RNA (dsRNA) is unstable in its natural form. Therefore, how to ensure the stability of dsRNA is one of the most significant challenges in realizing the commercial use of RNA biopesticides. Nanomaterials such as cationic polymers and lipofectamine can improve the stability of dsRNA in the environment, which has been proved. This paper reviews the recent research progress of nanomaterials that can be used to improve the environmental stability of dsRNA, and discusses the advantages and limitations of different nanomaterials combined with dsRNA, which provides reference for the selection of dsRNA nanoformulations.

A Gram-stain-negative, rod-shaped, exopolysaccharide-producing, strictly aerobic bacterium with a single polar flagellum, designated strain HL22-2 T , was isolated from a phosphate mine situated in a suburb of Kunmming in Yunnan province in south-western China. The taxonomic status of this strain was evaluated by using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HL22-2 T was related to members of the genus , 2007). At the time of writing, the genus Pseudomonas comprised at least 207 species with validly published names (http://www.bacterio.net/p/pseudomonas.html). During an investigation of the diversity of cultivable micro-organisms in a phosphate mining field ecosystem, strain HL22-2 T was isolated from phosphate rock powder samples and selected for further characterization using a polyphasic approach, including analysis of genotypic, chemotaxonomic and classical phenotypic characteristics. Based on our results, we consider that strain HL 22-2 T represents a novel species of the genus Pseudomonas.Strain HL 22-2 T was isolated from phosphate rock powder samples collected at a phosphate mining field situated in a suburb of Kunmming in Yunnan province in south-western China. A sample (1 g) was suspended in 9 ml sterile distilled water and serial dilutions were made. Aliquots (0.1 ml) of appropriate dilutions were spread on Luria-Bertani (LB pH 7.2; 1 % tryptone, 1 % NaCl, 0.5 % yeast extract; w/v) agar plates and incubated at 30 u C for 4-5 days. The purity of cultures was assessed by colony morphology and microscopy. For short-term preservation, serial transfer from agar slants to an appropriate medium was performed and the agar slants were stored at 4 u C. For long-term preservation, the strain was stored at 280 u C in LB broth with 20 % glycerol (v/v). For taxonomic purposes, Pseudomonas xanthomarina KMM 1447 T and Pseudomonas stutzeri ATCC 17588 T were purchased from their respective culture collection centres and used as reference strains.Abbreviation: EPS, exopolysaccharides.The GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain HL22-2 T is JQ246444.