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Ezra, D.

Publications and source records attributed to Ezra, D..

3 recordsLinked to original sources

Expansion and Comprehensive Evaluation of the Peacock Eye Disease Management (PedMan) System across Olive Cultivars Differing in Susceptibility to Venturia oleaginea

Peacock eye disease, caused by Venturia oleaginea , is an important foliar disease of olive that is primarily managed through fungicide applications. Integrating host resistance into disease-warning systems could improve spray timing and reduce unnecessary fungicide use. PedMan (Peacock eye disease Manager) was previously developed and validated for highly susceptible olive cultivars. The objectives of the present study were to expand PedMan to cultivars differing in susceptibility to V. oleaginea and to evaluate the expanded system under commercial grove conditions. A sensitivity analysis of the rainfall and temperature criteria used for highly susceptible cultivars was conducted to establish criteria for moderately susceptible and moderately resistant cultivars. The rainfall threshold of [≥]15 mm was retained, whereas the temperature range triggering an infection alert was narrowed from 12-18 {degrees}C for highly susceptible cultivars to 13-17 {degrees}C for moderately susceptible and 14-16 {degrees}C for moderately resistant cultivars. The expanded system was subsequently evaluated in 33 field trials and observations under natural infection conditions. PedMan recommendations were classified as correct or incorrect based on statistical comparisons of leaf abscission between fungicide-treated and untreated trees. Overall, 30 of 33 recommendations were correct, resulting in an accuracy of 90.9%. Sensitivity was 87.0%, while specificity and positive predictive value were both 100%. These results demonstrate that incorporating cultivar susceptibility into PedMan broadens its applicability and provides reliable cultivar-specific fungicide recommendations. The system has potential to reduce unnecessary fungicide applications while maintaining effective management of peacock eye disease across olive cultivars differing in susceptibility.

plant biology↗

Peacock Eye Disease Management (PedMan) System: Validation and Implementation in Addressing Key Biological Questions

Peacock eye disease, caused by Venturia oleaginea, is a major foliar disease of olive (Olea europaea) in Mediterranean regions, resulting in defoliation, reduced tree vigor, and yield losses. Effective disease management relies on precise fungicide timing. In this study, we validated a decision support system (DSS) named PedMan (Peacock eye disease Manager), designed to predict infection events and optimize fungicide application timing in highly susceptible olive cultivars based on rainfall and temperature conditions. The system was validated in seven independent grove experiments conducted during the 2023/24 and 2024/25 growing seasons in commercial olive orchards in Israel. In addition, simulation analyses were performed using weather data from 11 meteorological stations representing diverse climatic regions. Field validation showed that fungicide applications timed according to PedMan significantly reduced leaf abscission by approximately 60% compared with untreated controls. Applications made contrary to system recommendations did not improve disease control, confirming the reliability of both positive and negative predictions. Multi-season analyses indicated cumulative disease suppression, with up to 85% reduction in leaf abscission after three consecutive years of correctly timed applications. The system was implemented by olive growers in 2025/6 with applicable success. Simulation results showed that most infection events occurred in autumn and early winter, with rainfall as the primary driver in autumn and temperature as the main limiting factor in winter and spring. Across all regions and seasons, PedMan recommended 0-3 fungicide applications per season, comparable to or fewer than conventional spray programs. These findings demonstrate that PedMan is a robust, field-validated DSS that improves fungicide timing, enhances disease control efficiency, and supports sustainable management of peacock eye disease without increasing spray frequency under Mediterranean conditions.

plant biology↗

Autotrophic growth of E. coli is achieved by a small number of genetic changes

Synthetic autotrophy is a promising avenue to sustainable bioproduction from CO2. Here, we use iterative laboratory evolution to generate several distinct autotrophic strains. Utilising this genetic diversity, we identify that just three mutations are sufficient for E. coli to grow autotrophically, when introduced alongside non-native energy (formate dehydrogenase) and carbon-fixing (RuBisCO, phosphoribulokinase, carbonic anhydrase) modules. The mutated genes are involved in glycolysis (pgi), central-carbon regulation (crp), and RNA transcription (rpoB). The pgi mutation reduces the enzymes activity, thereby stabilising the carbon-fixing cycle by capping a major branching flux. For the other two mutations, we observe down-regulation of several metabolic pathways and increased expression of native genes associated with the carbon-fixing module (rpiB) and the energy module (fdoGH), as well as an increased ratio of NADH/NAD+ - the cycles electron-donor. This study demonstrates the malleability of metabolism and its capacity to switch trophic modes using only a small number of genetic changes and could facilitate transforming other heterotrophic organisms into autotrophs.

synthetic biology↗