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Bacterial leaf streak of small-grain cereals is an economically important disease of wheat and barley crops. The disease occurs in many countries across the globe, with a particular importance in regions characterized by high precipitations or the areas where sprinkler irrigation is used. Three genetically distinct lineages of the Gram-negative bacterium Xanthomonas translucens i.e. X. translucens pv. undulosa, X. translucens pv. translucens, and X. translucens pv. cerealis are responsible for most of the bacterial leaf streak infections on wheat and barley crops. Considering the seed-borne nature of the pathogens, they are included in the A2 (high-risk) list of quarantine organisms for some European countries; hence, they are under strict quarantine control and zero tolerance. Due to the taxonomic complexities within X. translucens, the exact geographic distribution of each pathovar has not yet been determined. In this mini-review, we provide an updated overview on the detection and diagnosis of the bacterial leaf streak pathogens. First, a short history of the leaf streak pathogens is provided, followed by symptomology and host range of the causal agents. Then, the utility of conventional methods and high throughput molecular approaches in the precise detection and identification of the pathogens is explained. Finally, we highlight the role of quarantine inspections and early detection of the pathogen in combating the risk of bacterial leaf streak in the 21st century’s small-grains cereals’ industry.

Mycopathogenic bacteria play a pivotal role in the productivity of edible mushrooms grown under controlled conditions. In this study, we carried out a comprehensive farm survey and sampling (2018 to 2021) on button mushroom ( Agaricus bisporus) farms in 15 provinces in Iran to monitor the status of bacterial pathogens infecting the crop. Mycopathogenic bacterial strains were isolated from pins, stems, and caps, as well as the casing layer on 38 mushroom farms. The bacterial strains incited symptoms on mushroom caps ranging from faint discoloration to dark brown and blotch of the inoculated surfaces. Among the bacterial strains inciting disease symptoms on bottom mushroom, 40 were identified as Ewingella americana based on biochemical assays and phylogeny of 16S rRNA and the gyrB gene. E. americana strains differed in their aggressiveness on mushroom caps and stipes, where the corresponding symptoms ranged from deep yellow to dark brown. In the phylogenetic analyses, all E. americana strains isolated in this study were clustered in a monophyletic clade closely related to the nonpathogenic and environmental strains of the species. BOX-PCR-based fingerprinting revealed intraspecific diversity. Using the cutoff level of 73 to 76% similarity, the strains formed six clusters. A chronological pattern was observed, where the strains isolated in 2018 were differentiated from those isolated in 2020 and 2021. Taken together, due to the multifaceted nature of the pathogen, such a widespread occurrence of E. americana on mushroom farms in Iran could be an emerging threat for the mushroom industry in the country.

Goss's bacterial wilt and leaf blight of maize (Zea mays) caused by the gram-positive coryneform bacterium Clavibacter nebraskensis is an economically important disease in North America. C. nebraskensis is included within the high-risk list of quarantine pathogens by several plant protection organizations (EPPO code: CORBMI), hence it is under strict quarantine control around the world. The causal agent was reported for the first time on maize in Nebraska (USA) in 1969. After an outbreak during the 1970s, prevalence of the disease decreased in the 1980s to the early 2000s, before the disease resurged causing a serious threat to maize production in North America. The re-emergence of Goss's wilt in the corn belt of the United States led to several novel achievements in understanding the pathogen biology and disease control. In this review, we provide an updated overview of the pathogen taxonomy, biology, and epidemiology as well as management strategies of Goss's wilt disease. First, a taxonomic history of the pathogen is provided followed by symptomology and host range, genetic diversity, and pathogenicity mechanisms of the bacterium. Then, utility of high-throughput molecular approaches in the precise detection and identification of the pathogen and the management strategies of the disease are explained. Finally, we highlight the role of integrated pest management strategies to combat the risk of Goss's wilt in the 21st century maize industry.Large (2-15 cm) tan to grey elongated oval lesions with wavy, irregular water-soaked margins on the leaves. The lesions often start at the leaf tip or are associated with wounding caused by hail or wind damage. Small (1 mm in diameter), dark, discontinuous water-soaked spots, known as "freckles", can be observed in the periphery of lesions. When backlit, the freckles appear translucent. Early infection (prior to growth stage V6) may become systemic and cause seedlings to wilt, wither, and die. Coalescence of lesions results in leaf blighting.Maize (Zea mays) is the only economic host of the pathogen. A number of Poaceae species are reported to act as secondary hosts for C. nebraskensis.Class: Actinobacteria; Order: Micrococcales; Family: Microbacteriaceae; Genus: Clavibacter; Species: Clavibacter nebraskensis.Corynebacterium nebraskense (Schuster, 1970) VidaverMandel 1974; Corynebacterium michiganense pv. nebraskense (VidaverMandel 1974) DyeKemp 1977; Corynebacterium michiganense subsp. nebraskense (VidaverMandel 1974) CarlsonVidaver 1982; Clavibacter michiganense subsp. nebraskense (VidaverMandel 1974) Davis et al. 1984; Clavibacter michiganensis subsp. nebraskensis (VidaverMandel 1974) Davis et al. 1984.ATCC 27794Cells are gram-positive, orange-pigmented, pleomorphic club- or rod-shaped, nonspore-forming, nonmotile, and without flagella, approximately 0.5 × 1-2.0 μm.The pathogen is restricted to Canada and the United States.EPPO code CORBNE.

Background: Bacterial ring rot of potato (Solanum tuberosum) caused by the gram- positive coryneform bacterium Clavibacter sepedonicus is an important quarantine dis-ease threatening the potato industry around the globe. Since its original description in 1906 in Germany, management of ring rot has been a major problem due to the seed-borne nature (via seed tubers not true seeds) of the pathogen allowing the bacterium to be transmitted long distances via infected tubers.Disease symptoms: On growing potato plants: interveinal chlorosis on leaflets leading to necrotic areas and systemic wilt. On infected tubers: vascular tissues become yel-lowish brown with a cheesy texture due to bacterial colonization and decay.Host range: Potato is the main host of the pathogen, but natural infection also occurs on eggplant, tomato, and sugar beet.Taxonomic status of the pathogen: Class: Actinobacteria; Order: Actinomycetales; Family: Microbacteriaceae; Genus: Clavibacter; Species: Clavibacter sepedonicus(Spieckermann and Kotthoff 1914) Li et al. 2018.Synonyms (nonpreferred scientific names): Aplanobacter sepedonicus; Bacterium sepe-donicum; Corynebacterium sepedonicum; Corynebacterium michiganense pv. sepedoni-cum; Clavibacter michiganensis subsp. sepedonicus.Microbiological properties: Gram- positive, club-shaped cells with creamy to yellowish-cream colonies for which the optimal growth temperature is 20–23°C.Distribution: Asia (China, Japan, Kazakhstan, Nepal, North Korea, Pakistan, South Korea, Uzbekistan, the Asian part of Russia), Europe (Belarus, Bulgaria, Czech Republic, Estonia, Finland, Georgia, Germany, Greece, Hungary, Latvia, Lithuania, Norway, Poland, Romania, European part of Russia, Slovakia, Spain, Sweden, Turkey, Ukraine), and North America (Canada, Mexico, USA).Phytosanitary categorization: CORBSE: EPPO A2 list no. 51. EU; Annex designation I/A2.

Data security, complete system control, and missed storage and computing opportunities in personal portable devices are some of the major limitations of the centralized cloud environment. Among these limitations, security is a prime concern due to potential unauthorized access to private data. Biometrics, in particular, is considered sensitive data, and its usage is subject to the privacy protection law. To address this issue, a multimodal authentication system using encrypted biometrics for the edge-centric cloud environment is proposed in this study. Personal portable devices are utilized for encrypting biometrics in the proposed system, which optimizes the use of resources and tackles another limitation of the cloud environment. Biometrics is encrypted using a new method. In the proposed system, the edges transmit the encrypted speech and face for processing in the cloud. The cloud then decrypts the biometrics and performs authentication to confirm the identity of an individual. The model for speech authentication is based on two types of features, namely, Mel-frequency cepstral coefficients and perceptual linear prediction coefficients. The model for face authentication is implemented by determining the eigenfaces. The final decision about the identity of a user is based on majority voting. Experimental results show that the new encryption method can reliably hide the identity of an individual and accurately decrypt the biometrics, which is vital for errorless authentication.

This paper addresses the notion of the impact of mobile learning technology from the learner's as well as educator's point of view. The authors have outlined the application of the e-learning in smart classes, which is followed by a similar argument with regard to the m-learning technology. This is followed by a statistical evaluation of the m-learning which through multiple surveys is conducted among the undergraduate and postgraduate students as well as the academics. In conclusion, the outcomes of these surveys are presented in graphical forms that highlight the merits and demerits of the m-learning technology.

In todays advanced technology environment, we come across a number of research areas that require extensive data processing. These areas include but not limited to, modeling and simulation of accuracy, safety and reliability of nuclear weapons, global warming, weather forecasting, DNA computing, nanotechnology, immune cell system, optical computing. Since we constantly continue to explore new avenues in our research program, hence the demand for improvements in other scientific and engineering parameters are continuously on the rise. These scientific and engineering requirements include but not limited to speed, reliability, fault tolerance, availability, compatibility, scalability, flexibility, cost to name a few. In todays environment, utilisation of parallel processing not only satisfies increasing demand for extensive data processing, yet it relatively fulfils deficiencies that one would experience in these scientific and engineering requirements. To this effect the authors have introduced architectures based on Master-Slave Multi-Super-Hypercube DX-Tree architecture and Master-Slave Multi-Super- Hypercube Star Ring Architecture. For these architectures and the current message passing architectures, the total system costs are developed and through mathematical modeling and simulation are compared. In this comparison the merit and demerits of these architectures from the cost point of view are highlighted to enable the user to select an appropriate Message-Passing architecture which would best satisfy ones scientific requirements.

The main objective of this work is to design and construct a small multiple microprocessor system based on the cross-bar switch architecture. The motives behind this are twofold; firstly there seems to be great potential in the architecture, and secondly, few previous constructional projects employing this architecture have been reported. A system is presented employing three Z80 microprocessors in a master-slave configuration with a floppy disc based support system. The various design decisions are outlined, and an estimate is made of the reliability of the hardware. This work, in particular, has highlighted the flexibility and simplicity of the architecture, in addition to the obvious potential of high speed of operation. It is also found that parallel programs can easily map onto the system, though this is not dealt with here.