PhD students' projects
1. Title: Evaluation of local fungal endophyte isolates for enhancing melon (Cucumis melo L.) plant tolerance to salinity and Fusarium Wilt.
Funded by: Deanship of Scientific Research, The University of Jordan
Status: Ongoing.
Supervisor/s: Dr. Jamal Ayyad and Dr. Kholoud M. Alananbeh
Student name: Yahia Dana
Abstract: Endophytes, including fungi and bacteria, are microorganisms that reside within plant tissues without causing harm, playing a key role in improving nutrient uptake, pathogen resistance, and stress mitigation, including salinity. Melon (Cucumis melo L), a warm-season crop of significant importance in the Jordan Valley and desert areas, faces challenges such as soil salinity and Fusarium wilt disease. In 2017, melon cultivation in the region spanned 1194 hectares, yielding over 60,000 metric tons, with a large portion directed to export markets. These areas, including Al-Karamah, Ghour Al-Safi, Wadi Araba, and others, are prone to salinity levels ranging from 4.5 to 14.1 dS m−1, which hampers water absorption by melon plants, leading to poor growth and yields. Furthermore, Fusarium wilt, caused by Fusarium oxysporum f.sp. melonis, results in severe damage to melon crops worldwide, with losses of up to 30% annually. Despite the challenges, limited research exists on the use of local fungal endophytes to enhance melon tolerance to salinity and Fusarium wilt. Exploring these endophytes offers an opportunity to improve melon growth and productivity under these stress conditions. Given the regional and local challenges, there is an urgent need to focus on such research, which could lead to sustainable agricultural practices and improved productivity in melon farming. Understanding and utilizing local endophytes could not only address these critical challenges but also contribute to ecosystem sustainability by enhancing agricultural resilience.
Publication/s: -
2. Title: A Study of Entomofauna of the Wasit Nature Reserve in Emirate of Sharjah, United Arab Emirates.
Supervisor/s: Dr. Ahmad Katbeh and Dr. Kholoud M. Alananbeh
Student name: Duaa Ramadan
Abstract: The Wasit Nature Reserve (WNR) is considered as the 'lungs of Sharjah' due to its diverse ecosystem, which includes coastal dunes (microhabitat), salt flats (variable area), ponds, and a large lake. It also provides a suitable environment for various terrestrial and aquatic insects. These insects play a vital role in maintaining the ecosystem of WNR, which is home to over 200 species of migratory birds and numerous mammals and reptiles. However, no previous studies have been conducted to classify insects within WNR in Sharjah (Wasit Nature Reserve Authority, 2022). Research on arthropod biodiversity (including insects) in UAE is urgently needed, as habitats are being degraded, fragmented, or destroyed before the baseline of arthropod species can be established and their ecological roles fully understood (Howarth. B & Gillett. M, 2009). A variety of insect species are found in WNR, and these insects play crucial roles in the food chain across different ecosystems. Moreover, they act as consumers, decomposers, predators, or parasites, and their presence can have significant direct or indirect effects on the living organisms in the reserve, and serve as research sites for scientists, providing valuable insights into the functioning of ecosystems and the impact of human activities on the environment. In addition, they provide unique opportunities for eco-tourism and educational programs, allowing tourists to discover insects' vital role in ecosystems, enhance their understanding, and foster greater environmental awareness while supporting conservation efforts. The study of insects in WNR includes identifying them and understanding their role in maintaining the balance of the ecosystem.
2. Title: Pathogenic variability of indigenous oat crown rust Puccinia coronata f. sp. avenae on different oat genotypes.
Status: Completed
Supervisor/s: Dr. Kholoud M. Alananbeh
Student name: Mohasad Ibrahim
Abstract: Crown rust caused by Puccinia coronata f. sp. avenae (Pca) is one of the most important diseases that infect both cultivated and wild oat plants all over the world, especially the main area of oat cultivation. Crown rust disease has two types of hosts that are needed to complete its life cycle: the primary host which is the oat plants, and the alternative host which is the buckthorn plant. The present study surveyed and identified the presence of crown rust, oat, and buckthorn plants in Jordan and the nature of their interaction under the country environmental conditions. GPS coordinates, species/subspecies identification, and the relationships of host and pathogen were observed and recorded. In the identification part both morphological and molecular ways were considered. Also, two field experiments were conducted in Deir-Alla, an area with optimum environmental conditions, to investigate the presence of resistance in wild oat against Pca under natural and artificial inoculation on two different seasons. Puccinia graminis f.sp. avena (Pga) was included in this study as an observational data and comparison purposes in this study. For the survey results, a variation in prevalence of Pca from year to another was observed, with 2023 with the highest prevalence. Identification of wild oat landraces that was based on morphological and molecular methods, showed that wild oats belonged mainly to A. sterilis (n=276) and A. barbata (n=30). Moreover, buckthorn specimens were identified mainly as Rh. lycioides with subspecies graecae (n=42) and lycioides (n=2) and few as Rh. XIV Punctata (n=2) based on morphological characters. Observations showed that there was no role for buckthorn surveyed as an alternative host of Pca infection. In the field experiment grown in Deir-Alla, promising results were found in both experiments of natural and artificial infection. For the natural infection, Pca-resistance was more profound than Pga resistance in wild oats that were naturally infected. Non-infected (0%) wild oats with Pca were 10-fold more than Pga. On the other hand, completely infected (100%) wild oats with Pga were 5-folds more than Pca. For the artificial infection, Pca-resistance was more profound in seedling stage than in adult stage. Non-infected (0%) wild oats at seedling stage were 19-folds more than adult stage. On the other hand, completely infected (100%) wild oats at adult stage were 13-folds more than seedling stage. The current research provides a foundation for future investigations that are focusing on evaluating wild oat accessions for potential resistant genes against Pca at seedling and adult stage under controlled greenhouse conditions.
Publication/s:
Master's students' projects
1. Title: Characterization of Local Trichoderma spp. for Hydrolytic Enzyme Activity, Abiotic Stress Tolerance, and Antagonism Against Fusarium oxysporum.
Status: Ongoing
Supervisor/s: Dr. Kholoud M. Alananbeh and Dr. Malik AL-Ajlouni
Student name: Suhaib Alelimat
Abstract: The vital role of Trichoderma spp. as eco-friendly biocontrol agents and plant growth promoters, offering sustainable alternatives to chemical pesticides and fertilizers in agriculture. Understanding their mechanisms of action, such as producing hydrolytic enzymes, plant growth regulators, and siderophores, provides valuable insights into their role in enhancing plant health and combating pathogens. Their ability to tolerate environmental stresses like salinity, heat, pH fluctuations, and UV exposure ensures their effectiveness under diverse field conditions. Additionally, the application of Trichoderma in crops like cucumber demonstrates its practical value in vegetables, promoting growth and reducing the need for chemical inputs. Ultimately, by enhancing plant resistance and productivity, Trichoderma spp. can significantly improve crop yields while maintaining environmental sustainability and supporting the economic well-being of farmers. This research aims to assess the production of hydrolytic enzymes and the stress tolerance (pH, heat, salinity, and UV radiation) of local Trichoderma spp.. The study will also evaluate the effectiveness of these isolates as biocontrol agents against Fusarium oxysporum, the causative agent of Fusarium wilt in cucumber, both in vitro (antagonistic assays) and in vivo (seedling experiments). This will provide a deeper understanding of their practical applications in sustainable agriculture. Trichoderma spp., particularly T. harzianum strain T22, are commonly used as seed treatments to control diseases. Under stress conditions, seeds treated with Trichoderma consistently showed faster and more uniform germination and better seedling performance compared to untreated seeds (Mastouri et al., 2010).
2. Title: Study on the Biological Control of Musca domestica in Jordan: Evaluating Entomopathogenic Fungi, Bacteria, and Parasitoids for Sustainable Pest Management.
Supervisor/s: Dr. Kholoud M. Alananbeh and Dr. Salah Araj
Student name: Khalaf Alenezi
Abstract: This study is important for developing sustainable pest management strategies in Jordan by exploring multiple biological control methods for Musca domestica, a significant pest affecting public health and agriculture. By assessing the impact of locally isolated entomopathogenic fungi and bacteria on fly larvae, the study aims to evaluate their potential for effective biological control in local environments. Additionally, examining the potential of S-Methoprene, a juvenile hormone analogue, provides an alternative control method by disrupting the development of house flies. Furthermore, the abovementioned methods will reduce the reliance on chemical pesticides.
3. Title: Evaluation of the effectiveness of local fungal isolates and comparison of their efficacy with acaricide against two-spotted spider mite (Tetranychus urticae) in vitro condition.
Student name: Ragad Abu Libdeh
Abstract: The two-spotted spider mite (Tetranychus urticae) is a highly destructive agricultural pest that affects over 1,275 plant species, including economically important crops such as fruits, vegetables, and ornamentals, leading to substantial yield losses due to mesophyll collapse, chlorosis, and necrotic spots (Jakubowska et al., 2022). In Jordan, T. urticae was identified as a major pest in both open-field and greenhouse-grown crops, causing severe economic damage, with approximately 66,000 plastic greenhouses affected by this pest as of 2009 (Al-Mommany and Al-Antary, 2008; Al-Antary and Salim, 2013). The main challenge in controlling T. urticae lies in its rapid resistance development against synthetic acaricides, attributed to its short life cycle and high reproductive potential. The overuse of chemical acaricides led to severe resistance issues, environmental pollution, and public concerns regarding pesticide residues in food products. Consequently, alternative control strategies, such as microbial biopesticides and integrated pest management (IPM), have gained attention for sustainable and effective pest suppression (Sousa Neto et al., 2020). Among biocontrol agents, entomopathogenic fungi (Metarhizium anisopliae and Beauveria bassiana) have shown promising results in controlling T. urticae by penetrating its cuticle and causing mortality through mycosis (Elhakim et al., 2020; Mariam et al., 2016). However, the compatibility and effectiveness of these biopesticides when combined with chemical acaricides remain unclear. Additionally, certain chemical acaricides may either enhance (synergistic effect) or inhibit (antagonistic effect) the efficacy of biocontrol agents, making their selection crucial in integrated pest management programs (Hernández et al., 2012; López-Manzanares et al., 2022). Chitinase enzymes, which play a key role in microbial biocontrol by degrading arthropod exoskeletons, further contribute to pest suppression, yet their potential in IPM strategies is not fully explored (Örtücü & Albayrak İskender, 2017). Thus, this study aims to evaluate the in vitro effectiveness of local entomopathogenic fungal isolates (Beauveria bassiana and Metarhizium anisopliae) against Tetranychus urticae, and to compare their efficacy with selected chemical acaricides. Additionally, the study investigates potential synergistic or antagonistic interactions between fungal biopesticides and chemical acaricides to assess their compatibility within integrated pest management (IPM) strategies. The research also examines the presence of chitinase enzymes in the fungal isolates as a potential factor contributing to their biocontrol activity.
4.Title: Ecology (spatial distribution and genetic diversity) and biology (microbial communities) study of Syrian mesquite (Prosopis farcta (Banks & Sol.) J.F.Macbr.) in the Jordan Valley.
Status: Completed.
Supervisor/s: Dr. Kholoud M. Alananbeh and Dr. Yahia Othman
Student name: Farah Al-Amir
Abstract: This research facilitated an extensive exploration and examination of the spatial distribution, weed classification, endophytic microbial communities, soil characteristics, and genetic diversity associated with Syrian mesquites (P. farcta). By addressing various aspects of P. farcta ecology and biology, this study will enhance our understanding of its invasive behavior and ecological impact. Additionally, this study will incorporate a diverse array of methodologies, including field surveys, morphological and molecular analyses, microbial culturing and sequencing, and soil characterization techniques. This methodological integration enables us to acquire comprehensive datasets and confirm findings through multiple analytical approaches.
5. Title: Influence of Trichoderma harzinum on growth, yeild and quality of lettuce (Lactuca sativa L.) grown under hydroponic system
Supervisor/s: Dr. Yahia Othman and Dr. Kholoud M. Alananbeh
Student name: Lojain Faeq Alzyod
Abstract: Lettuce is a potential source of iron, vitamins, fibers and several other health-beneficial phenolic compounds. Therefore, increasing lettuce yield while maintain/enhancement of its phenolic compounds is critical. Two experiments were carried out to identify the proper stage (germination or seedling) to inoculate Trichoderma harzianum on lettuce (experiment 1) and to investigate the effect of using T. harzianum on growth, yield and quality (phenolic compounds) of lettuce cultivars grown under Nutrient Film Technique (NFT) hydroponic system (experiment 2). The study was conducted in the laboratories and greenhouse at the University of Jordan using one Romane type “Nebrase" and two Iceberg “Lolo Rossa" “Lolo Bionda" lettuce cultivars. During the study period, leaf physiology, yield and yield quality (phenols flavonoids and scavenging activity) were evaluated. Experiment 1 showed that the three inoculation approaches of T. harzianum; at seed stage, transplant stage (adding T. harzianum solution to root system) or directly adding T. harzianum spores to nutrient solution inside the tank had similar results in term of shoot and root growth. During the second experiment (NFT) two cycles were evaluated. The response of lettuce plants to T. harzianum in Cycle 1 which was under high temperatures (33± 3 °C) was better than cycle 2; at which plants were under unstressed condition (winter). In fact, most tested variables in cycle 2 from inoculated and non-inoculated treatments were not significantly different. Overall, our results revealed that the response of lettuce cultivar to Trichoderma inoculation under hydroponic culture can be significantly positive under stressed conditions.