Planting under plastic-film mulches is widely used in spring maize production in arid-cold regions for water conservation and warming the soil.  To ameliorate the associated issues such as plastic-film residues and additional labor during the “seedling release” in spring maize production, we have developed a plastic-film-side seeding (PSS) technology with the supporting machinery.  In the semi-arid regions of Northwest China, a 7-year trial demonstrated that PSS increased plant number per hectare by 6 547 and maize yield by 1 686 kg ha^–1 compared with the traditional method of seeding under plastic-film mulch (PM).  Two-year experiments were conducted in two semi-arid regions to further understand the effects of PSS on three important aspects of production: (i) the moisture and temperature of soil, (ii) maize development, yield output, and water use efficiency (WUE), and (iii) the revenue and plastic-film residuals in comparison with that of flat planting (CK) and PM.  Continuous monitoring of the soil status demonstrated that, compared with CK, the PSS treatment significantly increased the temperature and moisture of the 0–20 cm soil in the seeding row at the early stage of maize development, and it also promoted grain yield (at 884–1 089 kg ha^–1) and WUE, achieving a similar effect as the PM treatment.  Economically, the labor inputs of PSS were equal to CK, whereas the PM cost an additional 960 CNY ha^–1 in labor for releasing the seedlings from below the film.  Overall, the PSS system increased profits by 5.83% (547 CNY ha^–1 yr^–1) and 8.16% (748 CNY ha^–1 yr^–1) compared with CK and PM, respectively.  Environmentally, PSS achieved a residual film recovery rate of nearly 100% and eliminated 96 to 130 kg ha^–1 of residual plastic-film in PM in 3–5 years of maize production.  Collectively, these results show that PSS is an eco-friendly technique for improving yield stability and incomes for the sustainable production of maize in semi-arid regions.

Huanglongbing (HLB, or citrus greening) is the most destructive disease of citrus, which is associated with Candidatus Liberibacter asiaticus (Las). Few management options are available, aside from preventive measures such as removing infected plants, planting disease-free seedlings, and managing the insect vector. In this study, we assessed the efficacy of thermotherapy against HLB under controlled greenhouse conditions. A total of 60 two-year-old, graft-infected Citrus reticulata Blanco plants were used. The plants were randomly divided into three groups (45°C, 48°C, and untreated control), with five plants/replicate (rep) and four reps/treatment. The treated plants were placed in phytotrons for a 4-h treatment session, repeated once per week for three consecutive weeks. Disease remission was observed eight weeks post-treatment. Real-time PCR assays revealed that Las titers in HLB-affected seedlings were significantly reduced in both 45 and 48°C treatments four weeks after treatment, with the exception of eight plants. In contrast, Las titers in the untreated control plants increased significantly during the same period, with a maximum increase of 28-fold. Except for seven plants, Las titers in the new flushes of treated plants decreased more than 90% eight weeks after treatment. Las titers in mature leaves of treated plants decreased 56 and 60% in average at 45 and 48°C, respectively, eight weeks after treatment. The HLB symptoms and Las titer of seedings were markedly alleviated eight weeks after treatment in both 45 and 48°C treatments. Our results laid a good foundation for the further development of citrus free-disease seedling cultivation and Huanglongbing control in the field. The whole plants were replaced for scion or branch in previous as the research object in this study, and the expression of Huanglongbing symptoms combined with real-time polymerase chain reaction (PCR) were used to evaluate the effect of heat treatment in the greenhouse.

Two Klebsiella pneumoniae isolates (Kpc1 and Kpc2) were obtained from liver samples of seven dead chickens and identified with Vitek-32 automated identification system. Antimicrobial susceptibilities were determined by the microdilution broth method. Detection of genes encoding class A b-lactamases was performed by PCR amplification, and cloning of the ESBL gene was by plasmid restriction and fragments ligation. Conjugation assay, transformation experiments and plasmid profile analysis were performed. The incompatibility group of ESBL-carrying plasmid was determined by the PCR-based replicon typing method. Lastly, the genetic environment was analysed by direct sequencing of the DNA surrounding the ESBL gene. The genes associated with tetracycline and gentamicin resistance were also sought by PCR. The results revealed that the ESBL phenotype-negative strain Kpc2 only showed resistance to ampicillin, amoxicillin, tetracycline, and doxycycline and carried blaTEM-1 and tet(A) genes. The ESBL-producing strain Kpc1 exhibited multidrug resistant phenotype and harbored blaTEM-1, blaCTX-M-14, tet(A), tet(B), and rmtB genes. K. pneumoniae Kpc1 contained four plasmids with molecular sizes of approximately 59, 6.9, 2.8, and 1.6 kb, but only a 59-kb plasmid, carried blaTEM-1 and blaCTX-M-14 genes, was observed in its transconjugant. The incompatibility group of plasmid carrying blaCTX-M-14 gene could not be determined. The blaCTX-M-14 gene was flanked upstream by an ISEcp1 insertion sequence and downstream by an IS903 element. This work shows that CTX-M-14 is present in K. pneumoniae isolates from chickens in China. The blaCTX-M-14 gene was associated with an upstream ISEcp1 insertion sequence. Our results underline the need for continuous surveillance of the prevalence and evolution of this CTX-M-type b-lactamase in China.