The main aim of this study was to improve fungal resistance in bread wheat via transgenesis. Transgenic wheat plants harboring barley chitinase (chi26) gene, driven by maize ubi promoter, were obtained using biolistic bombardment, whereas the herbicide resistance gene, bar, driven by the CaMV 35S promoter was used as a selectable marker. Molecular analysis confirmed the integration, copy number, and the level of expression of the chi26 gene in four independent transgenic events. Chitinase enzyme activity was detected using a standard enzymatic assay. The expression levels of chi26 gene in the different transgenic lines, compared to their respective controls, were determined using qRT-PCR. The transgene was silenced in some transgenic families across generations. Gene silencing in the present study seemed to be random and irreversible. The homozygous transgenic plants of T4, T5, T6, T8, and T9 generations were tested in the field for five growing seasons to evaluate their resistance against rusts and powdery mildew. The results indicated high chitinase activity at T0 and high transgene expression levels in few transgenic families. This resulted in high resistance against wheat rusts and powdery mildew under field conditions. It was indicated by proximate and chemical analyses that one of the transgenic families and the non-transgenic line were substantially equivalent. Transgenic wheat with barley chi26 was found to be resistant even after five generations under artificial fungal infection conditions. One transgenic line was proved to be substantially equivalent as compared to the non-transgenic control.

This work aimed to evaluate one hundred and fifty-five commercial wheat fields included six varieties to yellow rust (stripe rust) epidemics caused by Puccinia striiformis f. sp. tritici, in Gharbia governorate during the 2019 to 2021 seasons. Also, study weather variables associated with yellow rust outbreaks in wheat. Temperature, relative humidity, and rain variables were obtained from the regional climate model imeto2 (http//meto.at/farmview/) as well as the World Climate Research Programme (WCRP) Global Energy and Water Cycle Experiment's (GEWEX) Surface Radiation Budget (NASA/GEWEX SRB) during the infection period from January to March. Results revealed that the high disease epidemic linked to rain precipitation and number of precipitation days combined with the minimum temperatures (5−10°C) and relative humidity (RH) at least 60%. Levels of yellow rust severity varied according to the studied year, and wheat variety. Gemmeiza-11, Sids-12, Misr-1, and Misr-2 were the most susceptible varieties, while both of Gemmeiza12 and Sakha95 were resistance to yellow rust disease along the studied period. In 2021 season all the wheat varieties showed resistance response. The loss % ranged between 36.00, 40.00 %(Gemmeiza-11); 36.00, 37.25% (Sids-12); 25.00, 33.33% (Misr1) and 21.21, 24.84% (Misr-2) in 2019 and 2020 growing seasons, respectively compared to the grain yield in 2021 season. Low disease severities were detected ranging from zero to trace infection (2.00%) in the 2021 season. High and positive correlation coefficient (R2) was found between disease severity % and loss in grain yield of he tested wheat varieties.

Ten stem rust monogenic lines and 14 commercial wheat cultivars were estimated under natural infection of stem rust disease for adult plant resistance (APR) during the 2019 – 2021 growing seasons at Gemmeiza Agricultural Research Station, ARC. Obtained results showed that Sr46, Sr47, and Sr51 were completely resistant along the three seasons, however, Sr50 showed zero to trace % resistance. The rest of the Srs tended to have a susceptibility ranging between 20% and 80%. The genes Sr54 and Sr45 had the highest mean values of area under disease progress curve (AUDPC) and rate of disease increases (r-value) followed by Sr49, Sr52, Sr48, and Sr53, respectively. Local wheat cultivars Gemmeiza-9, Gemmeiza-10, Gemmeiza-11, Gemmeiza-12, Giza-171, Sakha-94, Sakha-95, Sids-14, and Shandweel-1 showed different resistance values ranging from (immune) zero to 10 moderately resistance (MR). While, Giza-168, Sids-12, Misr-3, Misr-2, and Misr-1 cultivars respectively displayed susceptibility ranging between moderately susceptible Tr-MS to susceptible 60S. Six simple sequence repeat (SSR) markers linked to stem rust resistance genes i.e. Sr45, Sr46, Sr47, Sr49, Sr50, and Sr52, respectively were selected to test their presence/absence in fourteen Egyptian wheat cultivars. The SSR results indicated the presence of Sr45, Sr46, and Sr49 in the tested Egyptian cultivars. Sr47 was positive in all cultivars except in Misr-2, while Sr50 was present only in Gemmeiza-12, Gemmeiza-9, Gemmeiza-11, Gemmeiza-10, Shandweel-1, and Sakha-94 cultivars. However, Sr52 is present in all tested cultivars except Gemmeiza-11. Sr49, Sr50, and Sr52 displayed high levels of polymorphism (75, 100, and 100%, respectively) as analyzed the iMEC software.

This study was carried out in the 2023/2024 wheat-growing season to identify the pathogen that infected the durum wheat cultivar Beni-Sweif-5 grown in the production sector, Sids agricultural research station. The stems and spike holders of the wheat cultivar showed dark browning ring symptoms. Initial infection symptoms appeared as brown discoloration then turned into dark brownish, then followed by drooping of the spikes to the ground. This cultivar was sown in 200 feddans (83.36 hectares) grown on Sids Agricultural Research Station farm (Agric. Res. Stn.), Beni-Sweif governorate. Disease incidence ranged from 10-15 % in all the growing areas. The isolated fungus characterized morphologically as Cladosporium cladosporioides in the Mycology Dept., Plant Pathology Research Institute (PPATHRI), ARC. The internal transcribed sequence (ITS) region of isolated fungus amplified by ITS1 and ITS4 primers pair, morphological and molecular studies confirmed that the causal fungus is Cladosporium cladosporioides. Phylogenetic relationships showed high homology 100 % with other Cladosporium isolates on the Gen Bank database.This isolate is released with accession number OM722086 in the NCBI/Gene Bank database. To our knowledge, this is the first record of the fungus Cladosporium cladosporioides ondurum wheat in Egypt.

Ensuring sustainable wheat production is crucial for food security, particularly in regions facing plant diseases and environmental challenges. In the Middle East, wheat powdery mildew, caused by Blumeria graminis f. sp. tritici, significantly threatens yields and quality, making it essential to comprehend local pathotype virulence and resistance genes for effective disease management. Therefore, 252 infected leaves were sampled from cultivated bread wheat genotypes in Egypt Delta region during 2024–2025 growing seasons. Forty-one powdery mildew monogenic lines (Pm) and twelve new bread wheat genotypes were evaluated at seedling and adult stages. Pathotype analysis identified six pathotypes in 2024 (IOEE most common, 22.91%) and four in 2025 (POKE dominant, 34.25%). Virulence diversity declined significantly: Shannon diversity decreased from 5.90 to 3.73, and Simpson diversity decreased from 5.81 to 3.58, indicating reduced pathotype complexity. No virulence was detected against Pm11, Pm13, Pm24, Pm25, Pm29, Pm32, Pm34, Pm35, Pm36, Pm37, Pm43, NCA9, and MIAB10 genes. PERMANOVA analysis showed no significant compositional difference between seasons (R² = 0.112, p = 0.481), with low genetic differentiation (mean character difference = 0.1894; Roger’s distance = 0.1914). Sakha96 wheat genotype displayed complete resistance at both growth stages, while Misr4, Misr5, Sakha95, Sids15, and Gemmeiza13 showed adult-stage resistance only in both seasons. Molecular analysis revealed that Pm24, Pm35 and Pm37 were absent in all genotypes. Pedigree analysis demonstrated Pm35 and Pm37 share common ancestral origins across Egyptian wheat germplasm. So, these resistant genotypes and broadly effective resistance genes provide valuable resources for breeding durable powdery mildew resistance in Egyptian wheat.