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Water use and salinity dynamics in the soils are the crucial management factors influencing the productivity and long-term sustainability of almond and associated environment. In this study, HYDRUS-2D was calibrated and validated on measured spatial and temporal water contents and soil salinities ( EC e ) distributions under almond irrigated with different water qualities ( EC iw ) at different physiological stages. During two irrigation seasons (2014–15 and 2015–16), less saline irrigation water (average EC iw 0.78 dS/m) was substituted for recycled irrigation water (average EC iw 1.9 dS/m) in three phenologically different growth stages; pre-pit hardening, kernel growth, and post-harvest, along with no and full substitution during the entire season. Graphical and statistical comparisons (RMSE, MAE, ME, the Nash and Sutcliffe model efficiency, and the coefficient of determination) between measured and simulated values of water contents and EC e in the soil showed a close agreement in all treatments. The water balance data revealed that the seasonal crop evapotranspiration of almond ( ET c ) varied from 850 to 955 mm in different treatments over the two seasons which represented 68–79% of the water application. Trees irrigated with only less saline water through the two seasons (average EC iw 0.78 dS/m) showed 10% higher plant water uptake as compared to those irrigated with recycled water only (average EC iw 1.9 dS/m). Substituting less saline irrigation during the kernel growth phase, between pit-hardening and harvest, showed greater water uptake by almond and lower salinity buildup in the soil as compared to treatments that substituted less saline irrigation early or late in the season. For all treatments, the average daily root zone EC e (2.4–3.7 dS/m) remained above the level of the almond salinity tolerance threshold ( EC e  = 1.5 dS/m) throughout the period of investigation. Water use efficiency of almonds varied in a narrow range (0.21–0.25 kg m −3 ) for different treatments. Deep drainage below the root zone (2 m) varied from 22.4–31.1% of the total water application (Rainfall + Irrigation), which was episodic and insufficient to contain the salinity below the almond threshold. This study provided a greater understanding of soil water and salinity dynamics under almond irrigated with waters of varying qualities. [ABSTRACT FROM AUTHOR]

Exiguobacterium spp. are alkaliphilic, halotolerant, non-spore-forming Gram-positive bacilli, hitherto uncharacterised from human infections. Six isolates of Exiguobacterium aurantiacum were obtained from patients with bacteraemia, three of whom had myeloma. All isolates formed orange–yellow pigmented colonies on blood agar, were catalase- and DNase-positive, and grew on nutrient agar at pH 10 and in the presence of NaCl 6% w/v. The six isolates were susceptible to all antimicrobial agents tested and were uniform in their fatty acid and mass spectrum profiles. [ABSTRACT FROM AUTHOR]

TEM-1 and TEMpUC19β-lactamases can gain activity against ceftazidime and other expanded-spectrum cephalosporins via point mutation. The frequency of emergent resistance to ceftazidime at 4 × MIC was elevated ≥ 250-fold in hyper-mutable, MutS-deficient Escherichia coli harbouring these β-lactamase genes on high- or low-copy plasmids. Moreover, although ceftazidime-resistant mutants, or those with reduced susceptibility, were selected in both the wild-type and mutS hosts, many more mutants in the mutS host showed ceftazidimase-type extended-spectrum β-lactamase (ESBL) activity. This correlated with a G–A point mutation at position 484 in the blaTEM-1 and blaTEM-pUC19 genes, conferring the Arg164His amino-acid substitution found in the TEM-29 ESBL. Non-ESBL mutants lacked changes in blaTEM. [ABSTRACT FROM AUTHOR]

Clin Microbiol Infect 2010; 16: 1111–1116 Repeat numbers at nine variable-number tandem-repeat (VNTR) loci were determined for 177 isolates of Pseudomonas aeruginosa representing 77 strains distinguished by pulsed-field gel electrophoresis (PFGE). Eight loci provided for discrimination similar to that provided by PFGE, with variation at the ninth locus (ms61) sometimes allowing discrimination within a PFGE-defined type. The Liverpool and Midlands 1 strains, which are common among patients with cystic fibrosis in the UK, could be unambiguously identified by their characteristic VNTR profiles. In rare cases, the repeat number at the ninth locus alone provided discrimination among isolates that were distinct according to PFGE. In each case, the two isolates shared the same blaOXA-50-like allele and belonged to the same oprD sequence type group, supporting the VNTR results in suggesting that they are similar. [ABSTRACT FROM AUTHOR]

Representatives ( n = 31) of outbreak strains of Acinetobacter baumannii from five countries fell into three clear groups, designated Groups 1–3, based on their ompA (outer-membrane protein A), csuE (part of a pilus assembly system required for biofilm formation) and blaOXA-51-like (the intrinsic carbapenemase gene in A. baumannii) gene sequences. With the exception of the closely related alleles within the Group 1 clonal complex, alleles at each locus were highly distinct from each other, with a minimum of 14 nucleotide differences between any two alleles. Isolates within a group shared the same combination of alleles at the three loci, providing compelling evidence that the outbreak strains investigated belonged to three clonal lineages. These corresponded to the previously identified European clones I–III. Sequence differences among the alleles were used to design multiplex PCRs to rapidly assign isolates belonging to particular genotypes to sequence groups. In the UK, genotypes belonging to the Group 1 clonal complex have been particularly successful, accounting for the vast majority of isolates referred from hospitals experiencing problems with Acinetobacter. [ABSTRACT FROM AUTHOR]

• This study evaluates the impact of recycled water (RCW) irrigation on salinity and sodicity hazards in soils. • Potential yields of horticultural crops reduced by 4-32% due to increase in the soil salinity. • RCW irrigation results in poor growing conditions due to steep increase in SAR and ESP in the soils. • Threshold SAR for the development of critical ESP (>6) varied from 3- 6 in different soils • The impact of RCW irrigation was more pronounced in calcareous and hard red brown soils. • Lon-term studies are essential to identify critical soil constraints impacting crop yields. The variably-saturated flow and multi-component transport module UNSATCHEM of HYDRUS-1D was used to evaluate the impact of the long-term (2018-2050) application of recycled water (RCW) for irrigating perennial horticulture (almonds, pistachios), viticulture (grapevines), annual horticulture (carrot, onion, and potato), and pasture crops in representative soils from the Northern Adelaide Plains (NAP), South Australia. The input parameters for soil hydraulic, soil solution, and cation exchange data were determined for 14 soil profiles from the NAP region. For a warm-up period from 1970 to 2017, the model used historical climate data and low-salinity irrigation water. In the subsequent period (2018-2050), irrigation continued with RCW and projected meteorological conditions were obtained by considering expected future climate change. The average soil water salinity (EC sw) at the end of the simulation period ranged from 2.9-10.5 dS/m across all soils and crops. Potential yields of salt-sensitive crops such as annual horticulture and almonds were reduced by 4-32% due to increased salinity in the soil. Similarly, the model predicted that the sodium adsorption ratio (SAR) and exchangeable sodium percentage (ESP) would increase above threshold values, typically considered as indicative of poor growing conditions for most crops. Relationships between SAR and ESP were developed for four representative soils, providing the threshold soil SAR that corresponds to a critical ESP (>6), which would lead to adverse soil health and crop growth impacts. Threshold SARs were derived for calcareous (SAR = 4), hard red-brown (SAR = 3.5), sand over clay (SAR = 6), and deep uniform to gradational (SAR = 3) soils. An increase in SAR and ESP in soils adversely affects soil structural stability and soil water movement, which can severely impact the sustainable crop production in the NAP region. Relationships such as those between SAR and ESP help in identifying critical soil constraints and assist in devising better guidelines for the sustainable use of recycled water for irrigated agriculture. [ABSTRACT FROM AUTHOR]