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The development of leaf blotch epidemics was studied in a range of spring barley cultivars at Aberystwyth, and infection rates were calculated to permit comparison both between cultivars and with other experiments. In 1972, infection rates ranged from 0.120 (cv. Proctor) to 0.208 (cv. Berac), and in 1973 from, 0.034 (cv. Proctor) to 0.084 (cv. Cambrinus). It is suggested on the basis of disease incidence and meteorological data, that resistance equivalent to that of cv. Proctor will provide adequate control of leaf blotch in most areas of Britain. It may, however, be difficult to detect such resistance in glasshouse experiments or other small-scale tests. [ABSTRACT FROM AUTHOR]

The ability to directly modify native and established biofilms has enormous potential in understanding microbial ecology and application of biofilm in 'real-world' systems. However, efficient genetic transformation of established biofilms at any scale remains challenging. In this study, we applied an ultrasound-mediated DNA delivery (UDD) technique to introduce plasmid to established non-competent biofilms in situ. Two different plasmids containing genes coding for superfolder green fluorescent protein (sfGFP) and the flavin synthesis pathway were introduced into established bacterial biofilms in microfluidic flow (transformation efficiency of 3.9 ± 0.3 × 10 -7 cells in biofilm) and microbial fuel cells (MFCs), respectively, both employing UDD. Gene expression and functional effects of genetically modified bacterial biofilms were observed, where some cells in UDD-treated Pseudomonas putida UWC1 biofilms expressed sfGFP in flow cells and UDD-treated Shewanella oneidensis MR-1 biofilms generated significantly (P < 0.05) greater (61%) bioelectricity production (21.9 ± 1.2 µA cm -2 ) in MFC than a wild-type control group (~ 13.6 ± 1.6 µA cm -2 ). The effects of UDD were amplified in subsequent growth under selection pressure due to antibiotic resistance and metabolism enhancement. UDD-induced gene transfer on biofilms grown in both microbial flow cells and MFC systems was successfully demonstrated, with working volumes of 0.16 cm 3 and 300 cm 3 , respectively, demonstrating a significant scale-up in operating volume. This is the first study to report on a potentially scalable direct genetic engineering method for established non-competent biofilms, which can be exploited in enhancing their capability towards environmental, industrial and medical applications., (© 2021 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

The precision and repeatability of in vivo biological studies is predicated upon methods for isolating a targeted subsystem from external sources of noise and variability. However, in many experimental frameworks, this is made challenging by nonstatic environments during host cell growth, as well as variability introduced by manual sampling and measurement protocols. To address these challenges, we developed Chi.Bio, a parallelised open-source platform that represents a new experimental paradigm in which all measurement and control actions can be applied to a bulk culture in situ. In addition to continuous-culturing capabilities, it incorporates tunable light outputs, spectrometry, and advanced automation features. We demonstrate its application to studies of cell growth and biofilm formation, automated in silico control of optogenetic systems, and readout of multiple orthogonal fluorescent proteins in situ. By integrating precise measurement and actuation hardware into a single low-cost platform, Chi.Bio facilitates novel experimental methods for synthetic, systems, and evolutionary biology and broadens access to cutting-edge research capabilities., Competing Interests: The authors have declared that no competing interests exist.

A type of chromosome-free cell called SimCells (simple cells) has been generated from Escherichia coli , Pseudomonas putida , and Ralstonia eutropha. The removal of the native chromosomes of these bacteria was achieved by double-stranded breaks made by heterologous I-CeuI endonuclease and the degradation activity of endogenous nucleases. We have shown that the cellular machinery remained functional in these chromosome-free SimCells and was able to process various genetic circuits. This includes the glycolysis pathway (composed of 10 genes) and inducible genetic circuits. It was found that the glycolysis pathway significantly extended longevity of SimCells due to its ability to regenerate ATP and NADH/NADPH. The SimCells were able to continuously express synthetic genetic circuits for 10 d after chromosome removal. As a proof of principle, we demonstrated that SimCells can be used as a safe agent (as they cannot replicate) for bacterial therapy. SimCells were used to synthesize catechol (a potent anticancer drug) from salicylic acid to inhibit lung, brain, and soft-tissue cancer cells. SimCells represent a simplified synthetic biology chassis that can be programmed to manufacture and deliver products safely without interference from the host genome., Competing Interests: Competing interest statement: C.F., I.P.T., H.Y., Z.C., and W.E.H. have filed a provisional patent application with the UK Patent Office related to this work., (Copyright © 2020 the Author(s). Published by PNAS.)

Background: The fungal genus Aspergillus is of critical importance to humankind. Species include those with industrial applications, important pathogens of humans, animals and crops, a source of potent carcinogenic contaminants of food, and an important genetic model. The genome sequences of eight aspergilli have already been explored to investigate aspects of fungal biology, raising questions about evolution and specialization within this genus., Results: We have generated genome sequences for ten novel, highly diverse Aspergillus species and compared these in detail to sister and more distant genera. Comparative studies of key aspects of fungal biology, including primary and secondary metabolism, stress response, biomass degradation, and signal transduction, revealed both conservation and diversity among the species. Observed genomic differences were validated with experimental studies. This revealed several highlights, such as the potential for sex in asexual species, organic acid production genes being a key feature of black aspergilli, alternative approaches for degrading plant biomass, and indications for the genetic basis of stress response. A genome-wide phylogenetic analysis demonstrated in detail the relationship of the newly genome sequenced species with other aspergilli., Conclusions: Many aspects of biological differences between fungal species cannot be explained by current knowledge obtained from genome sequences. The comparative genomics and experimental study, presented here, allows for the first time a genus-wide view of the biological diversity of the aspergilli and in many, but not all, cases linked genome differences to phenotype. Insights gained could be exploited for biotechnological and medical applications of fungi.

Parallel questionnaires that enquired into the beliefs and behaviours which related to the acquired immunodeficiency syndrome (AIDS) were administered by postal survey during August and September 1987 to two separate samples of students. Each sample comprised 300 students who were selected at random, were aged up to 30 years, and at the time were enrolled at The University of Sydney; the response rate was 70%. Results showed a high level of "correctness" of belief about AIDS and safer sexual practices. More than half the population had experienced sexual intercourse during 1987, 25% of whom had experienced sexual intercourse on a casual basis. A marked discrepancy was found between the knowledge of and the performance of safer sexual behaviours, as measured by two sets of key questions, which covered condom use in casual vaginal encounters and enquiry into a casual partner's history with regard to sexual experience, abuse of intravenous drugs and history of blood transfusions. A log-linear regression analysis showed no correlation between scores on the two sets of key questions on knowledge of safer sexual practices and the demographic variables of age, sex, sexual experience or religious commitment. It is suggested that an educational campaign that is directed at the problem of behavioural change will fail to be productive if it is focused narrowly on the knowledge of safer sexual techniques; in addition, it should take into account other attitudinal components, such as the perception of social pressures from peer-groups. Within this particular student population, the most-effective immediate stratagem may be to restructure the perceived personal and peer-group risks.