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Herbicidal residues of imazamox are hazardous to some sensitive rotational aftercrops. The aim of the study was to isolate and identify a microbial strain capable of degrading imazamox. The strain IB5, capable of efficiently degrading imazamox, was isolated from an imazamox-contaminated soybean field in Heilongjiang Province, China. It was found to degrade 98.61% of 400 mg L−1 imazamox within 48 h by high-performance liquid chromatograph. Through morphological, physiological and biochemical characterization, and the 16S rDNA sequencing, the strain was identified as Acinetobacter baumannii. An optimal degradation condition was obtained and verified: 400 mg L−1 imazamox, 0.1% (volume ratio) initial inoculum, 37°C and pH 7.0. Four main products were captured in the liquid chromatograms and mass spectra, and a pathway for imazamox degradation by IB5 was proposed. This work provides a new suitable candidate for imazamox biodegradation and theoretical evidence for imazamox residue bioremediation. A. baumannii is a common clinical bacteria, but its imazamox-degrading feature has not been reported previously.

The production of sugar beet and maize as energy crops were investigated in saline alkali soil in China during three growing seasons. A dramatically decreases of yield of grains and starch of maize was found in both medium and heavy saline-alkali soil in the three years. But there were no decreases of yield of root and sucrose of sugar beet in medium saline-alkali soil and reduction of yield of root and sucrose of sugar beet in heavy medium saline-alkali were faintly. The results indicate that sugar beet is more tolerant to salt stress and maintains higher production of sugar may be a major bioethanol crops in saline-alkali soil in China.

Background Jasmonic acid (JA) and methyl jasmonate (MeJA) regulate plant development, resistance to stress, and insect attack by inducing specific gene expression. However, little is known about the mechanism of plant defense against herbivore attack at a protein level. Using a high-resolution 2-D gel, we identified 62 MeJA-responsive proteins and measured protein expression level changes. Results Among these 62 proteins, 43 proteins levels were increased while 11 proteins were decreased. We also found eight proteins uniquely expressed in response to MeJA treatment. Data are available via ProteomeXchange with identifier PXD001793. The proteins identified in this study have important biological functions including photosynthesis and energy related proteins (38.4%), protein folding, degradation and regulated proteins (15.0%), stress and defense regulated proteins (11.7%), and redox-responsive proteins (8.3%). The expression levels of four important genes were determined by qRT-PCR analysis. The expression levels of these proteins did not correlate well with their translation levels. To test the defense functions of the differentially expressed proteins, expression vectors of four protein coding genes were constructed to express in-fusion proteins in E. coli. The expressed proteins were used to feed Ostrinia furnacalis, the Asian corn borer (ACB). Our results demonstrated that the recombinant proteins of pathogenesis-related protein 1 (PR1) and thioredoxin M-type, chloroplastic precursor (TRXM) showed the significant inhibition on the development of larvae and pupae. Conclusions We found MeJA could not only induce plant defense mechanisms to insects, it also enhanced toxic protein production that potentially can be used for bio-control of ACB. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1363-1) contains supplementary material, which is available to authorized users.

An allele of the cytochrome P450 gene, CYP6AE14, named CYP6AE25 (GenBank accession no. EU807990) was isolated from the Asian com borer, Ostrinia fumacalis (Guenée) (Lepidoptera: Pyralidae) by RT-PCR. The cDNA sequence of CYP6AE25 is 2315 bp in length and contains a 1569 nucleotides open reading frame encoding a putative protein with 523 amino acid residues and a predicted molecular weight of 59.95 kDa and a theoretical pI of 8.31. The putative protein contains the classic heme-binding sequence motif F××G×××C×G (residues 451-460) conserved among all P450 enzymes as well as other characteristic motifs of all cytochrome P450s. It shares 52% identity with the previously published sequence of CYP6AE14 (GenBank accession no. DQ986461) from Helicoverpa armigera. Phylogenetic analysis of amino acid sequences from members of various P450 families indicated that CYP6AE25 has a closer phylogenetic relationship with CYP6AE14 and CYP6B1 that are related to metabolism of plant allelochemicals, CYP6D1 which is related to pyrethroid resistance and has a more distant relationship to CYP302A1 and CYP307A1 which are related to synthesis of the insect molting hormones. The expression level of the gene in the adults and immature stages of O. furnacalis by quantitative real-time PCR revealed that CYP6AE25 was expressed in all life stages investigated. The mRNA expression level in 3(rd) instar larvae was 12.8- and 2.97-fold higher than those in pupae and adults, respectively. The tissue specific expression level of CYP6AE25 was in the order of midgut, malpighian tube and fatty body from high to low but was absent in ovary and brain. The analysis of the CYP6AB25 gene using bioinformatic software is discussed.