Lytic and Molecular Evidence of the Widespread Coriander Leaf Spot Disease Caused by Alternaria dauci.

Coriandrum sativum L. is a globally significant economic herb with medicinal and aromatic properties. While coriander leaf blight disease was previously confined to India and the USA, this study presents new evidence of its outbreak in Africa and the Middle East caused by Alternaria dauci. Infected leaves display irregular chlorotic to dark brown necrotic lesions along their edges, resulting in leaf discoloration, collapse, and eventual death. The disease also impacts inflorescences and seeds, significantly reducing seed quality. Koch's postulates confirmed the pathogenicity of the fungus through the re-isolation of A. dauci from artificially infected leaves, and its morphology aligns with typical A. dauci features. Notably, this study identified strong lytic activity (cellulase: 23.76 U, xylanase: 12.83 U, pectinase: 51.84 U, amylase: 9.12 U, and proteinase: 5.73 U), suggesting a correlation with pathogenicity. Molecular characterization using ITS (ON171224) and the specific Alt-a-1 gene (OR236142) supports the fungal morphology. This research provides the first comprehensive documentation of the pathological, lytic, and molecular evidence of A. dauci leaf blight disease on coriander. Future investigations should prioritize the development of resistant coriander varieties and sustainable disease management strategies, including the use of advanced molecular techniques for swift and accurate disease diagnosis to protect coriander from the devastating impact of A. dauci.

Fingerprinting Chemical Markers in the Mediterranean Orange Blossom Honey: UHPLC-HRMS Metabolomics Study Integrating Melissopalynological Analysis, GC-MS and HPLC-PDA-ESI/MS.

(1) Background: Citrus honey constitutes a unique monofloral honey characterized by a distinctive aroma and unique taste. The non-targeted chemical analysis can provide pivotal information on chemical markers that differentiate honey based on its geographical and botanical origin. (2) Methods: Within the PRIMA project "PLANT-B", a metabolomics workflow was established to unveil potential chemical markers of orange blossom honey produced in case study areas of Egypt, Italy, and Greece. In some of these areas, aromatic medicinal plants were cultivated to enhance biodiversity and attract pollinators. The non-targeted chemical analysis and metabolomics were conducted using ultra-high-performance liquid chromatography high-resolution mass spectrometry (UHPLC-HRMS). (3) Results: Forty compounds were disclosed as potential chemical markers, enabling the differentiation of the three orange blossom honeys according to geographical origin. Italian honey showed a preponderance of flavonoids, while in Greek honey, terpenoids and iridoids were more abundant than flavonoids, except for hesperidin. In Egyptian honey, suberic acid and a fatty acid ester derivative emerged as chemical markers. New, for honey, furan derivatives were identified using GC-MS in Greek samples. (4) Conclusions: The application of UHPLC-HRMS metabolomics combined with an elaborate melissopalynological analysis managed to unveil several potential markers of Mediterranean citrus honey potentially associated with citrus crop varieties and the local indigenous flora.

Potential Role of Biochar and Silicon in Improving Physio-Biochemical and Yield Characteristics of Borage Plants under Different Irrigation Regimes.

Silicon (Si) and biochar (Bc) are key signaling conditioners that improve plant metabolic processes and promote drought tolerance. However, the specific role of their integrative application under water restrictions on economical plants is not yet well understood. Two field experiments throughout 2018/2019 and 2019/2020 were conducted to examine the physio-biochemical modifications and yield attributes of borage plants mediated by Bc (9.52 tons ha-1) and/or Si (300 mg L-1) under different irrigation regimes (100, 75, and 50% of crop evapotranspiration). Catalase (CAT) and peroxidase (POD) activity; relative water content, water, and osmotic potential; leaf area per plant and yield attributes; and chlorophyll (Chl) content, Chla/chlorophyllidea (Chlida), and Chlb/Chlidb were considerably reduced within the drought condition. On the other hand, oxidative biomarkers, as well as organic and antioxidant solutes, were increased under drought, associated with membrane dysfunction, superoxide dismutase (SOD) activation, and osmotic adjustment (OA) capacity as well as a hyperaccumulation of porphyrin intermediates. Supplementation of Bc and Si lessens the detrimental impacts of drought on several plant metabolic processes associated with increasing leaf area and yield attributes. Their application under normal or drought conditions significantly elicited the accumulation of organic and antioxidant solutes as well as the activation of antioxidant enzymes, followed by lessening the formation of free radical oxygen and mitigating oxidative injuries. Moreover, their application maintained water status and OA capacity. Si and/or Bc treatment reduced protoporphyrin, magnesium-protoporphyrin, and protochlorophyllide while increasing Chla and Chlb assimilation and boosting the ratio of Chla/Chlida and Chlb/Chlidb, resulting in a rise in leaf area per plant and yield components following these modifications. These findings highlight the significance of Si and/or Bc as (a) stress-signaling molecule(s) in regulating defensive systems in drought-affected borage plants by boosting antioxidant aptitude, regulating water status, and accelerating chlorophyll assimilation, thus leading to increasing leaf area and productivity.