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Aly A.A.,Egyptian Plant Pathology Research Institute | Hussein E.M.,Egyptian Plant Pathology Research Institute | Asran A.A.,Egyptian Plant Pathology Research Institute | Asran A.A.,Unit of Excellence in Nano Molecular Plant Pathology Research ARC | And 3 more authors.
Icelandic Agricultural Sciences | Year: 2013

The pathogenicity of 24 isolates of Rhizoctonia solani (7 isolates from anastomosis group AG-2 and 17 from AG-4) was evaluated on 10 flax cultivars under greenhouse conditions. Survival, plant height, and dry weight were used as criteria to evaluate pathogenicity. Analysis of variance (ANOVA) showed that the cultivar was a highly significant source of variation in all the tested parameters (P < 0.0002). Isolate was always a highly significant source of variation in all the tested parameters (P = 0.0000). Cultivar x isolate interaction was always a nonsignificant source of variation. The results of the ANOVA in the present study suggest that physiologic specialization did not occur within R. solani isolates pathogenic on flax. They also imply that resistance of the tested cultivars was only horizontal, and there were significant differences among cultivars in this type of resistance. Similarly, pathogenicity of the tested isolates was only aggressiveness, and the isolates significantly differed in this type of pathogenicity. A hierarchical cluster analysis was conducted in order to group the isolates according to disease variables measured on the tested cultivars. Cluster analysis divided the isolates into groups; however, grouping the isolates was not related to their geographic origin nor the AG.


Aly A.A.,Egyptian Plant Pathology Research Institute | Hussein E.M.,Egyptian Plant Pathology Research Institute | El-Awamri A.A.,Ain Shams University | Habeb M.M.,Ain Shams University | And 2 more authors.
Romanian Agricultural Research | Year: 2014

Trichoderma spp. were isolated from roots of cotton plants showing the typical symptoms of seedling damping-off or adult plants root rot. Identification of 15 randomly selected isolates of Trichoderma to species level revealed that eight isolates (53.3%) were belonging to T. longibrachiatum, while seven isolates (46.7%) were belonging to T. harzianum. Geographic origins of T. harzianum in the sample were restricted to the Nile Delta, while isolates of T. longibrachiatum were isolated from widely separated geographic origins in the Nile Delta, Middle Egypt, and Upper Egypt. The beneficial and deleterious effects of Trichoderma isolates on growth of cotton seedlings were evaluated by planting cotton seeds in autoclaved soil infested with Trichoderma isolates. Each of T. longibrachiatum and T. harzianum included both beneficial and deleterious isolates. Moreover, the same isolate may exhibit both the beneficial and deleterious effects depending on the variable under consideration. Biocontrol capacity of Trichoderma spp. against soil-borne fungi involved in cotton seedling damping-off was evaluated by planting cotton seeds in autoclaved soil infested with a mixture of the soilborne fungi commonly involved in the disease. Before planting, seeds were treated with a fine powder consisted of a mixture of sorghum and Trichoderma spp. Grouping the isolates by cluster analysis, based on their beneficial effects, deleterious effects, and biocontrol capacity, was neither related to their geographic origin nor their species.


Khiyami M.A.,King Abdulaziz City for Science and Technology | Almoammar H.,King Abdulaziz City for Science and Technology | Awad Y.M.,Suez Canal University | Alghuthaymi M.A.,Shaqra University | And 2 more authors.
Biotechnology and Biotechnological Equipment | Year: 2014

Plant diseases are among the major factors limiting crop productivity. A first step towards managing a plant disease under greenhouse and field conditions is to correctly identify the pathogen. Current technologies, such as quantitative polymerase chain reaction (Q-PCR), require a relatively large amount of target tissue and rely on multiple assays to accurately identify distinct plant pathogens. The common disadvantage of the traditional diagnostic methods is that they are time consuming and lack high sensitivity. Consequently, developing low-cost methods to improve the accuracy and rapidity of plant pathogens diagnosis is needed. Nanotechnology, nano particles and quantum dots (QDs) have emerged as essential tools for fast detection of a particular biological marker with extreme accuracy. Biosensor, QDs, nanostructured platforms, nanoimaging and nanopore DNA sequencing tools have the potential to raise sensitivity, specificity and speed of the pathogen detection, facilitate high-throughput analysis, and to be used for high-quality monitoring and crop protection. Furthermore, nanodiagnostic kit equipment can easily and quickly detect potential serious plant pathogens, allowing experts to help farmers in the prevention of epidemic diseases. The current review deals with the application of nanotechnology for quicker, more cost-effective and precise diagnostic procedures of plant diseases. Such an accurate technology may help to design a proper integrated disease management system which may modify crop environments to adversely affect crop pathogens. © 2014 The Author(s).


Almoammar H.,King Saud University | Almoammar H.,King Abdulaziz City for Science and Technology | Bahkali A.H.,King Saud University | Abd-Elsalam K.A.,Egyptian Plant Pathology Research Institute | Abd-Elsalam K.A.,Unit of Excellence in Nano Molecular Plant Pathology Research ARC
Australian Journal of Crop Science | Year: 2013

The main goal of our study was to identify Aspergillius spp. isolates by polyphasic taxonomic techniques. Differential culture media, biochemical and molecular characterization were applied to 21 isolates of Aspergillus flavus and Aspergillus niger from Saudi Arabia camel feeds. Six aflatoxin producing culture media were used for characterizing and identifying aflatoxigenic isolates. The blue fluorescent ring visible under UV light which indicates the ability to produce aflatoxin, by aflatoxinogenic strains was not observed for any of the tested non aflatoxigenic isolates. Biochemical characterization involving the screening of the isolates for five aflatoxins was also performed. As found, most isolates were capable of producing detectable levels of both B and G type's aflatoxins (AFs) and maltoryzine, although 4 of the 7 A. niger isolates failed to produce any detectable amount of AFs. PCR was performed using one set of primers that specifically targets the aflatoxin regulatory gene (aflR) involved in aflatoxin biosynthetic pathway as well as four specific primers for A. flavus and A. niger. The presence of the aflR gene did not correlate with aflatoxigenicity. Most of the fungi belonging to A. flavus group reacted positively with aflR primers that cover the region from 540 to 1338 of aflatoxin regulatory gene with product size of 798 base pairs (bp). All A. flavus isolates had positive PCR results using the primer pair FLA1-FLA. A unique DNA fragment of the expected 500-bp size was amplified in all A. flavus isolates, while no PCR products were visualized in other Aspergillus species or members belong to other fungal genera. Using the primer pairs OMt1R-OMt1F, a single fragment of about 1232 bp A. niger isolates was amplified but did not amplify with DNA extracted from other Aspergillus species or species belonging to other fungal genera. Detection and quantification of these two important aflatoxin-producing Aspergilli could provide important information to predict the aflatoxin profiles which may be present in the feed matrix. © 2013.


Rai M.,Sant Gadge Baba Amravati University | Rai M.,University of Campinas | Ingle A.P.,Sant Gadge Baba Amravati University | Ingle A.P.,Badrinarayan Barwale College | And 5 more authors.
Current Nanoscience | Year: 2013

Nanotechnology is essentially related with the synthesis of nanoparticles of varying size and shapes. with the search of environment- friendly protocols for the synthesis of nanoparticles a diverse group of biological agents have been emerged. These biological agents are safe, eco-friendly and lead to green synthesis of nanoparticles. The present review focuses on the role of biological agent(s) towards the development of green nanotechnology, the applications of nanoparticles in different fields of science and technology, and also the toxicological effects of nanoparticles. © 2013 Bentham Science Publishers.


Rai M.,Sant Gadge Baba Amravati University | Birla S.,Sant Gadge Baba Amravati University | Ingle A.P.,Sant Gadge Baba Amravati University | Gupta I.,Sant Gadge Baba Amravati University | And 4 more authors.
Nanotechnology Reviews | Year: 2014

Bionanotechnology is the field dealing with the synthesis and application of different nanomaterials. Nanoparticles usually form the core of nanobiomaterials. For the past decade, a variety of inorganic nanoparticles have been newly created to provide superior material properties. Nowadays, synthesis of nanoparticles is the area of interest due to their physical, chemical, optical, electronic properties, and most importantly their larger surface area-to-volume ratio. Synthesis of inorganic nanoparticles is done by various physical and chemical processes, but biological route of synthesis is gaining more importance due to their eco-friendly nature. Bioactivity of nanoparticles broadly involves the wide range of nanoparticles and their biological application. They have been used as new tools not only for investigation of biological processes but also for sensing and treating diseases. In this respect, they are appearing to be novel antimicrobial agents even against drug-resistant microorganisms. On the other side at higher concentration, they show toxicity to the humans and ecosystem. Therefore, in the present review, we have briefly described the synthesis of different metal nanoparticles by different approaches mainly paying attention to their biosynthesis, antimicrobial activity, and cytotoxicity. As silver nanoparticles are finding many applications among all of the inorganic nanoparticles, we paid special attention to them, too.


Nagi M.A.,King Saud University | Abd-Elsalam K.A.,Egyptian Plant Pathology Research Institute | Abd-Elsalam K.A.,Unit of Excellence in Nano Molecular Plant Pathology Research ARC | Bahkali A.H.,King Saud University | And 2 more authors.
Romanian Agricultural Research | Year: 2012

In the current study, we describe a DNA isolation method that is based on an easy, quick polyvinylpolypyrrolidone-precipitation to release phytofungi from the soil, combined with lysozyme- RNase and -SDS lysis of the fungal population. DNA extracts were subjected to different techniques, including gel electrophoresis, restriction enzyme digestion, RAPD and ITS-PCR amplification. The proposed method yielded high-quality DNA, which was transparent, non-viscous and lacked visible contamination of RNA. Isolated DNA was efficiently digested with restriction enzymes. DNA extracted from soil was pure enough to be utilized at high concentrations for PCR amplifications. The extracted DNA was of high quality and allowed direct detection of specific genes by the polymerase chain reaction (PCR). The amplicon length of the fragment ITS4/ITS5, ranged in size from 550 to 680 bp. A polymerase chain reaction method used to detect soil-borne plant pathogens such as Fusarium spp., Rhizoctonia solani and Macrophomina phaseolina in the soil was developed and used with a range of soil textures. A direct method for the extraction of DNA from soil samples, which can be used for PCR-mediated diagnostics without a need for further DNA purification, was developed. The developed protocol seemed adequate to the range of soil textures that were artificially infested by a variety of soil-borne pathogens.

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