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The quality of virgin olive oil is closely related to the quality of olive fruits. The primary aim of the present work was to assess the olive fruit quality of five major olive cultivars (Frantoio, Leccino, Ezhi-8, Picholine, and Coratina) cultivated in Longnan, which is an emerging region for olive plantation in China. Measurement and gravimetric methods were used to study the biological properties of olive fruits, while the biochemical constituents were analysed by colorimetry. The results of morphological and biochemical analyses showed that the olive fruits of the five cultivars had excellent quality with relatively high oil contents and bioactive components (flavonoids and phenolic compounds). The oil contents in freeze-dried sarcocarp ranged from 49.25 to 71.11%. The shape parameters, biological characteristics, and bioactive components of olive fruits varied with genetic characteristics of cultivar, ripeness, and physic- ochemical factors of soil. There was a certain negative correlation between total carbohydrate and oil content in sarcocarp, as well as between total polyphenol content and polyphenol oxidase activity. The principal component analysis (PCA) results showed that the evaluation indexes of the olive fruit quality mainly include the biological characteristic parameters (fruit size and weight, sarcocarp, and oil content) and the contents of bioactive components (saccharides, polyphenols, and flavonoids). Furthermore, the soil nutrients and physicochemical properties also affected the fruit quality. Our findings suggest that the olive fruit produced in Longnan has excellent production performance, and the fruit quality is closely correlated with the genotype of olive cultivar, growing environment, and soil conditions. [ABSTRACT FROM AUTHOR]

Lifespan of fine roots plays important roles in regulating carbon (C) cycling in terrestrial ecosystems. Determination of root lifespan and elucidation of its regulatory mechanism in different plant communities are essential for accurate prediction of C cycling from ecosystem to regional scales. Temperate steppes in Inner Mongolia grasslands have three major types, i.e., Stipa krylovii, Stipa grandis and Stipa breviflora grasslands. There have been no studies to compare the root dynamics among the three types of grasslands. In the present study, we determined root lifespan of the three grasslands using the rhizotron. We found that root lifespan differed substantially among the three types of grasslands within the temperate steppes of Inner Mongolia, such that root lifespan of Stipa breviflora > Stipa grandis > Stipa krylovii grasslands. Root lifespan across the three types of grasslands in the Inner Mongolian temperate steppes displayed a similar temporal pattern, i.e. lifespan of the roots produced in spring and autumn was shortest and longest, respectively, whereas lifespan of summer-produced roots was between that of roots produced in spring and autumn. The spatial and temporal differences in root lifespan across the three types of grasslands were mainly determined by contents of soluble sugars in roots of the dominant species. The differences in root lifespan across the major types of grasslands and different seasons highlight the necessity to take into account these differences in the prediction of C cycling within grassland ecosystem by the simulating model. [ABSTRACT FROM AUTHOR]