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Recent Submissions

Defining Soilborne Pathogen Complexes Provides a New Foundation for the Effective Management of Faba Bean Root Diseases in Ethiopia
Date: 2025-07-14
Status: Open access
Soilborne diseases cause losses of 45–70% in faba bean in Ethiopia. Studies were undertaken to define soilborne pathogens and their complexes in Ethiopia. First, the severity of root rot was assessed in 150 field sites across seven Ethiopian regions. Soil samples were collected, and the DNA of 29 pests and pathogens was quantified using a commercial quantitative PCR (qPCR) soil testing service. There was a very high incidence rate of Macrophomina phaseolina, as well as Pythium clades F and I. The other detected species in order of incidence included Fusarium redolens, Rhizoctonia solani, Aphanomyces euteiches, Phytophthora megasperma, Sclerotinia sclerotiorum and S. minor, and Verticillium dahliae, as well as low levels of Thielaviopsis basicola. Five anastomosis groups (AG) of R. solani, namely AG2.1, AG2.2, AG3, AG4, and AG5, were detected, of which AG2.2 and AG4 were most prevalent. We believe this is the first report of occurrence for Ethiopia of A. euteiches, Ph. megasperma, T. basicola, and the five AGs for R. solani. There were very high incidence rates of the foliar pathogens Botrytis cinerea, B. fabae, Didymella pinodes, and Phoma pinodella and of the nematode Pratylenchus thornei, followed by P. neglectus and P. penetrans. The root rot severity and distribution varied significantly across regions, as well as with soil types, soil pH, and soil drainage. Subsequently, metabarcoding of the soil DNA was undertaken using three primer pairs targeting fungi (ITS2), Fusarium species (TEF1 α), and Oomycetes (ITS1Oo). The ITS2 and TEF1α primers emphasized F. oxysporum as the most abundant soilborne fungal pathogen and highlighted F. ananatum, F. brachygibbosum, F. brevicaudatum, F. clavum, F. flagelliforme, F. keratoplasticum, F. napiforme, F. nelsonii, F. neocosmosporiellum, F. torulosum, and F. vanettenii as first reports of occurrence for Ethiopia. The ITS1Oo primer confirmed Pythium spp. as the most prevalent of all Oomycetes.
Spermidine alleviates drought-induced wheat floret degeneration by mitigating oxidative damage and maintaining energy homeostasis
Date: 2024-12-25
Status: Open access
Drought stress at the booting stage causes severe floret degeneration and a decrease in grain number. Polyamines are involved in wheat floret development under drought stress, but the underlying physiological mechanisms are unclear. This study showed that drought-induced accumulation of reactive oxygen species led to wheat spikelet cell apoptosis and floret degeneration. Drought induced stomatal closure to reduce photosynthesis, then inhibited the activities of sucrose phosphate synthase, sucrose synthetase (cleavage direction) and ADP-glucose pyrophosphorylase in spikes and leaves, and soluble vacuolar invertase and cell wall invertase in spikes, thus providing a poor nutrient base for floret development. Exogenous spermidine application increased antioxidant enzyme activities and polyamine metabolism, promoted starch and sucrose metabolism, amino acid utilization and increased the levels of glycolytic and tricarboxylic acid cycle intermediates to mitigate oxidative damage and maintain energy homeostasis in the spike, thereby reducing floret degeneration and increasing grain number.
Biochar induced trade-offs and synergies between ecosystem services and crop productivity
Date: 2024-10-17
Status: Open access
Biochar amendment offers a chance for sustainable agriculture. However, the effectiveness of biochar relies on its physical and chemical properties, which are heavily affected by biochar production conditions and management practices. Therefore, substantial uncertainties regarding the use of biochar exist in agricultural systems globally. This study provides the first quantitative evaluation of the impacts of biochar characteristics and management practices on key ecosystem services by performing a second-order meta-analysis based on 34,628 paired observations in biochar-amended and unamended systems. Overall, biochar enhances phytotoxicity alleviation, physiology regulation, soil remediation and carbon sequestration, and microbial functional gene abundance. However, some prominent trade-offs exist between crop productivity and ecosystem service deliveries including for nutrient cycling, microbial function, climate change mitigation, and the soil microbial community. The adoption of low C:N biochar produced at high pyrolysis temperatures from sewage sludge-derived feedstock, in combination with a moderate application rate and inorganic fertilizer input, shows potential for achieving synergistic promotion of crop productivity and ecosystem services. These outcomes highlight the need for judicious implementation of biochar-based solutions to site-specific soil constraints. The quantified synergy and tradeoff relationships will aid the establishment of a sustainable biochar development framework that strengthens necessary ecosystem services commensurate with food security assurance.
Making use of synergies from integrated land-climate-biodiversity action pays off
Author(s): Mirzabaev, Alisher; Bisom, Nina; Akramkhanov, Akmal; Ingabire, Chantal (DLG-Verlag GmbH Frankfurt, 2024-12-11)
Date: 2024-12-11
Status: Open access
Collaboration between the Rio Conventions and coordinated action both at international and national level could offer considerable benefits. Drawing on their research in Rwanda and Central Asia, our authors demonstrate the economic potential integrated approaches hold especially for land restoration.
Интегрированные действия по земле-биоразнообразию-климату: использование синергии посредством восстановления экосистем в Узбекистане
Author(s): Mirzabaev, Alisher; Akramkhanov, Akmal (Economics of Land Degradation Initiative (ELD), 2025-02-28)
Date: 2025-07-04
Status: Open access
Данное исследование по Узбекистану описывает методологические шаги, оценку затрат и выгод, потребности в институциональной координации и соответствие национальных стратегий целям Рио-конвенций.