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Background Date palm ((Phoenix doctylifera L.) suffers from several fungal diseases. The endophytic microorganisms present in higher plants generally offer protection to their host plants against invading phytopathogenic fungi and bacteria. In the present study, endophytic bacteria associated with date palm leaves were isolated and their in vitro antagonistic potential against fungal pathogens causing leaf spots in date palm was demonstrated. Results Endophytic bacteria were isolated from date palm leaves of 3 different cultivars viz., Nighal, Khalas and Khinaizi and evaluated for their inhibitory activity against leaf spot pathogens of date palm viz., Fusarium solani, Alternaria sp., Nigrospora sp., Thieloviopsis sp., Curvularia subpapendrofii and Tilletiopsis minor using an in vitro dual culture assay. Of the 24 endophytic bacterial strains tested, the endophytes designated B1, B7, B8 and B9 obtained from cv. Nighal showed inhibitory activities (more than 55% mycelial growth inhibition) against F. solani and Alternaria sp. None of the bacterial endophytes inhibited the growth of other fungal pathogens tested. These antagonistic bacterial strains were identified as Pantoea septica on the basis of 16S rRNA gene sequence analysis. The hyphae of F. solani and Alternaria sp. exhibited morphological abnormalities such as shrinkage and disintegration when grown in the presence of antagonistic bacterial endophytes. The cell-free culture filtrates of the bacterial endophytes caused inhibition of mycelial growth and induced leakage of electrolytes from the mycelia of F. solani and Alternaria sp. This is the first study that describes inhibition of the date palm pathogens F. solani and Alternaria sp. by P. septica. Conclusion Endophytic Pantoea septica strains isolated from date palm leaves inhibited the mycelial growth of F. solani and Alternaria sp. and induced morphological changes in their mycelia. The culture filtrates of these bacterial strains also inhibited the mycelial growth and caused leakage of electrolytes from the mycelia of F. solani and Alternaria sp. These promising bacterial strains can be exploited as biocontrol agents to control F. solani and Alternaria sp.-induced leaf spot diseases of date palm.

Date palm is the most important crop in Oman, occupying approximately 50% of the area devoted to agriculture. Little information is available on leaf spot diseases of date palm in Oman and in the w...

This paper aims to discuss the difficulties of using videoconferencing technology in supervisory practices, from an educational supervisory perspective. Whereas, although video conferencing technology is important; The number of educational supervisors who use it is not commensurate with its value and significance, as studies have reported on this technology, perhaps as a new technology. Therefore, the study aimed: to discuss the technical challenges, and the human challenges facing the use of videoconferencing technology in supervision. The researcher used the descriptive and analytical method, whereby a questionnaire was designed consisting of two axes: The first for technical difficulties consists of (11) phrases, and the second for human difficulties consists of (9) phrases. It was applied to a sample of (322) educational supervisors. The study found the following results: The existence of material obstacles that came to a large extent about the use of videoconferencing technology in supervisory operations, as the weakness of the Internet in some remote areas came in first place with the highest arithmetic average of (4.19), followed by “weak infrastructure of schools and directorates. Educational governorates "with an average of (4.08). Followed by the presence of human obstacles that came with a moderate degree regarding the use of video conferencing technology in supervisory operations. Lack of training in employing videoconferencing technology" came in first place with the highest arithmetic average of (3.96). The study includes a set of recommendations, including preparing an integrated guide to explain the mechanism of activating video conferencing in supervisory work. It includes analyzing and studying the psychological, technical and material factors facing the activation of video conferencing.

A study was conducted to evaluate genetic relatedness of 27 citrus cultivars and 6 wild citrus accessions using AFLP fingerprinting. The 27 citrus cultivars belonged to Citrus sinensis, C. aurantifolia, C. aurantium, C. paradise, C. reticulata, C. limon, C. latifolia, C. maxima, C. limettoides, C. limetta, C. medica and C. Jambhiri. The wild cultivars were obtained from Oman while the other cultivars originated from Oman and other countries. AFLP analysis using 4 primer pair combinations resolved 910 polymorphic alleles. All citrus cultivars and accessions had low genetic diversity (H = 0.0281 to 0.1300), with the percent polymorphic loci ranging from 8 to 35%. Populations of the six wild citrus accessions showed a very low level of genetic diversity (< 0.0700). Cluster analysis of the 33 cultivars and accessions showed that they share a high level of genetic similarity (81‒99%; mean = 92%). The six wild accessions clustered into two main clusters, with the analysis indicating that the six wild accessions may make up six distinct cultivars. The study provides information on the phylogeny of citrus cultivars and citrus diversity in Oman, a country through which citrus moved in the past from Asia to different African and European countries. In addition, it shows that some distinct citrus cultivars are present in this part of the world.

This study was conducted to investigate the Alternaria species associated with leaf spot of date palm and wheat in Oman. Out of 98 date palm leaf samples and 146 wheat leaf samples, Alternaria was isolated from 27 and 23% of the samples developing leaf spot symptoms, respectively. Identification of Alternaria isolates using sequences of the internal transcribed spacer region of the ribosomal RNA (ITS rRNA), glyceraldehyde-3-phosphate dehydrogenase (GPDH), translation elongation factor (TEF) and RNA polymerase II subunit (RPB2) genes, showed that the isolates belong to seven Alternaria species or species complexes. A. burnsii - A. tomato and A. arborescens species complexes (58 and 4%, respectively) and A. alternata (38%) were the species recovered from the symptomatic date palm leaves. A. alternata (67%), A. burnsii - A. tomato species complex (15%), A. jacinthicola (3%), A. ventricosa (3%), A. slovaca (6%) and Alternaria caespitosa (6%) were isolated from wheat. Pathogenicity test showed that tested isolates of A. alternata (DPM19, WDK12), A. burnsii - A. tomato species complex (DPM31), A. jacinthicola (WBR4) and A. slovaca (WDK9, WDK7) were pathogenic on date palm, while A. alternata (DPM19, WDK12), A. burnsii - A. tomato species complex (DPM31, WDK11) and A. slovaca (WDK9, WDK7) were pathogenic on wheat. This is the first report of date palm and wheat as new hosts for A. burnsii - A. tomato species complex and the first reports of A. burnsii - A. tomato species complex, A. caespitosa A. slovaca, and A. ventricosa in Oman. The study shows that several species of Alternaria are associated with leaf spot in date palm and wheat in Oman, with some isolates having the ability to cause infection in both hosts.

The focus of this study was to determine people's perception and knowledge toward land degradation and management in the Al-Suwaiq Wilayat of Al-Batinah North, Sultanate of Oman. This area has been under pressure and competed for by several uses. Structured questionnaire survey with questions related to land degradation and management were used for the assessment in the beginning of the year 2016. In total, 238 households were surveyed in the Wilayat following a random sampling method. The results indicate that residents were aware of the on-going land degradation due to salinization, construction, and public work activities in the area. Residents perceive land degradation mainly by reduced yields and the most important perceived indicator is loss of soil nutrients that reduced crop yield, reduction in family income followed by increased cost for management. The study findings highlight that sustainable use and management of land resources is required in creating awareness programs to educate resi...

The purpose of this study was to determine residents’ perception, knowledge and attitude towards environmental issues and management in the Al-Suwaiq Wilayat (administrative zone) of Al-Batinah North, Sultanate of Oman. For this purpose, a questionnaire was used with questions on issues related to environment and surveyed across 109 households in the Wilayat following a random sampling method in early 2015. The results show that education, health-related infrastructure and unemployment are ranked as most important issues for government attention today and in coming 10 years besides their concern for the environment. Resident’s perceptions on most important environmental issues were concerned about solid-waste pollution, degradation of coastal areas, saltwater intrusion and land degradation. The sources for environmental information, government agencies, local media and schools were regarded as most reliable. Top environmental priorities were suggested to deal with enforcement of regulations, provi...

This paper presents an analysis of anthropogenic pressures in terms of indicators which would contribute to the relative vulnerability of coastal Wilayats (Administrative Zones) to development and related activities in the Al-Batinah North region of Oman. The main objective of this work is to rank each Wilayat based on the pressure indicators to provide inputs for local stakeholders involved in coastal management by developing a sense of understanding on the relative vulnerability of coastal Wilayats. The study of using pressure indicators would help to identify, key development pressures with the potential to affect coastal ecosystems. This would also enable to identify a Wilayat having strong driving forces for development and to determine which Wilayat’s coastal ecosystems are most affected and relatively experiencing anthropogenic pressures. Results of ranking exercise indicated that Suwaiq and Sohar Wilayats are more vulnerable, having pressures of studied drivers such as agriculture and urbanization. The identified pressure indicators presented in this study could be used to design coastal monitoring systems that can help further development of holistic environmental and socio-economic indicators for the coast.

Background Trichoderma is one of the most common fungi in soil. However, little information is available concerning the diversity of Trichoderma in soil with no previous history of cultivation. This study was conducted to investigate the most common species and the level of genetic relatedness of Trichoderma species from uncultivated soil in relation to cultivated soil and potting media. Results A total of 24, 15 and 13 Trichoderma isolates were recovered from 84 potting media samples, 45 cultivated soil samples and 65 uncultivated soil samples, respectively. Analysis based on the internal transcribed spacer region of the ribosomal RNA (rRNA) and the translation elongation factor gene (EF1) indicated the presence of 9 Trichoderma species: T. harzianum (16 isolates), T. asperellum (13), T. citrinoviride (9), T. orientalis (3), T. ghanense (3), T. hamatum (3), T. longibrachiatum (2), T. atroviride (2), and T. viride (1). All species were found to occur in potting media samples, while five Trichoderma species were recovered from the cultivated soils and four from the uncultivated soils. AFLP analysis of the 52 Trichoderma isolates produced 52 genotypes and 993 polymorphic loci. Low to moderate levels of genetic diversity were found within populations of Trichoderma species (H = 0.0780 to 0.2208). Analysis of Molecular Variance indicated the presence of very low levels of genetic differentiation (Fst = 0.0002 to 0.0139) among populations of the same Trichoderma species obtained from the potting media, cultivated soil and uncultivated soil. Conclusion The study provides evidence for occurrence of Trichoderma isolates in soil with no previous history of cultivation. The lack of genetic differentiation among Trichoderma populations from potting media, cultivated soil and uncultivated soil suggests that some factors could have been responsible for moving Trichoderma propagules among the three substrates. The study reports for the first time the presence of 4 Trichoderma species in Oman: T. asperellum, T. ghanense, T. longibrachiatum and T. orientalis.