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[Display omitted] • Ca. 830 Ma alkaline mafic dykes are identified in the southern Yangtze Block. • These dykes are geochemically comparable to intraplate basaltic rocks. • They were likely from a previously metasomatized asthenosphere mantle. • Rifting occurred in the Yangtze Block during ca.830 Ma. The Neoproterozoic alkaline mafic rocks in the Yangtze Block are critical to investigate the magmatic and tectonic evolution of South China. However, these rocks are rarely exposed. We here present a detailed study of ca. 830 Ma alkaline mafic dykes newly identified from a drilled borehole at the Nage area in the southern Yangtze Block. The dykes have SIMS zircon U-Pb ages of 827 ± 8 Ma. They show coherent variations in major and trace elements, characterized by enrichment in LREE and incompatible elements and no significant Nb-Ta and Zr-Hf anomalies, suggesting that their parental magmas have experienced varying degrees of fractionation crystallization with negligible crustal contamination. Modeling calculations based on their ε Nd (T) values (-0.55–3.23), SiO 2 contents (48.38–53.61 wt%) and elemental ratios (e.g., La/Ta and Nb/La) suggest that the Nage mafic dykes were probably generated from an asthenospheric mantle with previously input of a plume-derived enrich component occurred within the source region rather than during ascent. Rocks from the Nage dykes exhibit OIB-like trace element and REE patterns as well as trace elemental compositions, which are different from arc-related igneous rocks but similar to alkaline basalts and mafic dykes formed in mantle plume related rifting systems around the world. In combination with tectonostratigraphic evidences, the Nage dykes in this study are suggested to have been generated in an intraplate rift which was probably induced by a mantle plume beneath the Yangtze Block. [ABSTRACT FROM AUTHOR]

• The appearance and nutritional quality of leaf mustard cultivars varied greatly. • Most phytochemicals content and antioxidant capacity decreased by fermentation. • The odor of Guizhou suancai was correlated with gluconapin. • The taste of Guizhou suancai was correlated with sinigrin. The flavor of Guizhou suancai fermented by the emerging varieties Zhuchang–2 (ZC–2) and Zhuchang Red (ZC Red) is superior to that of ZC–1, a typical local variety of leaf mustard in Guizhou Province, China. Here, changes in phytochemical qualities during the fermentation of three Guizhou suancai were characterized to identify the causes underlying differences in flavor. The content of pigments, antioxidants, gluconapin, gluconasturtiin, and total isothiocyanates, and antioxidant capacity were highest in fresh ZC Red. The content of sinigrin, indolic glucosinolates, and total glucosinolate breakdown products was highest in fresh ZC–2. The content of phytochemicals, with the exception of carotenoids, was significantly decreased after fermentation. Odor was correlated with gluconapin, while taste was correlated with sinigrin. These findings provide detailed insights into the sensory and phytochemical properties of three Guizhou suancai that could facilitate the selection of raw material varieties. [ABSTRACT FROM AUTHOR]