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The aims of current study are to asses the levels of heavy metals (Cr, Cu, Ni, Fe, Zn, Co, Pb, and Cd) in sediments of lakes in Yangtze wetland and discuss the relationships between the sources and human activities. A total of 54 samples covering seven lakes along the Yangtze route in Anqing were selected. The concentrations of metals in lake sediments were (mg-kg-1): Cr, 4.08-12.58; Cu, 22.40-74.36; Ni, 29.89~142.17; Fe, 22899.20~50956.40; Zn, 102.31~242.04; Co, 8.35~26.89; Pb, 23.38~88.77; and Cd, 0.29~2.95. The situation of Xizi Lake was the most serious among the seven lakes investigated. Geoaccumulation index (Igeo) analysis showed that overall risk of heavy metals in sediments was approximately in the order: Cd > Pb = Zn = Cu = Ni > Fe > Co = Cr. The results of principal component analysis (PCA) suggested the main sources of Cd, Cu, Zn, Ni, and Pb on PC 1 were fuel combustion, metal smelting, industrial manufacturing, and other human activities, while Fe on PC 2 originated from rock weathering and other geochemical processes. [ABSTRACT FROM AUTHOR]

To determine the age of oil-tea camellia trees, regression equations including Logistic, Mitscherlich, Gompertz, Korf, and Richards were used to calculate accumulative growth rate using basal trunk disc and investigate the relations between the age of oil-tea camellia trees and their growth rate of secondary trunk. The Gompertz equation Y =71.296 lexp (-3.874 4exp (-0.0064t)) was the most optimal equation to simulate the accumulative growth rate of basal trunk disc. This equation could be used to estimate the age of oil-tea camellia trees that grow under similar environmental conditions. The Korf equation Y = 576. 900 lexp (-4.153 0x-0.3142) was the best equation to describe the relation between the age and growth rate of different secondary trunks. With the adjustment coefficient and average growth of different secondary trunk discs, it is possible to predict the age of ancient oil-tea camellia trees that grow under similar environmental conditions. In addition, taking three or more discs from the same diameter group and calculating their average growth rate could lead to more accurate results. For trees that grow in different areas, environmental conditions should be carefully considered when using the above two equations to predict the age of ancient oil-tea camellia trees. [ABSTRACT FROM AUTHOR]

An rooting experiment of tissue culture plantlets was carried out with sterile plantlets obtained from the stem segments of a good clone of Camellia oleifera as materials. The results showed that basic medium and illumination condition are factors crucial to rooting of C. oleifera. With 1/4MS as basic medium, the treatment with the addition of 0. 5 mg/L NAA and soaking in 2 000 mg/L KIBA, containing 30 mg/L sucrose and subjected to dark culture of 20 d was the optimal treatment, achieving a rooting rate of 86.7%. [ABSTRACT FROM AUTHOR]

A new species, Polygonatum praecox Y.F.Hu & J. W.Shao (Asparagaceae), is described and illustrated. This species is similar to P. cyrtonema, P. odoratum and P. caulialatum, but can be distinguished from P. cyrtonema by its racemose inflorescence, cylindrical hairless filaments and apex without a retrorse spur; from P. odoratum by its stout moniliform rhizome, straight stem and longer (1.7-2.2 cm long) floral tube; and from P. caulialatum by its upper part straight stem, yellowish-green corolla, lobes excurved and earlier flowering. The complete chloroplast genome of this new species is 155,115-155,256 bp in length. Phylogenetic analysis revealed that P. praecox is not genetically related to the above three morphological similar species, but is closely related to the two European species (P. multiforum and P. latifolium). This species is relatively common in mid-eastern China and has previously been confused with P. cyrtonema. As its wild resources have decreased in recent years due to over-exploitation for medicinal or edible purposes, we classify it as Near Threatened (NT) according to the IUCN Red List Criteria. [ABSTRACT FROM AUTHOR]

This paper studied effects of different picking time and different geographical provenances on oil content of Camellia oleifera. The results showed that different picking time had significant effects on the oil content of cold dew seeds and frost’s descent seeds. With the delay of picking time, the oil content of cold dew seeds, frost’s descent seeds, dry seeds and oil content of seed kernels were significantly increased. There was a significantly positive correlation between the oil content of fresh fruit of cold dew seeds and frost’s descent seeds and the dry seed yield of fresh seeds and the oil content of fresh fruit (P < 0. 05), and the correlation coefficient was greater than 0. 85. Besides, the oil content of seed kernels of cold dew seeds was closely correlated with the seed yield of fresh seeds, oil content of fresh fruit, and oil content of fresh seeds. In the process of C. oleifera breeding, the thin coat, high seed yield and high oil content can be taken as the key research directions for future breeding. The oil content of ordinary C. oleifera seeds in 18 counties (cities) was 36. 42%-63. 33%, indicating that there were significant differences in the oil content of C. oleifera in different geographical provenances. In conclusion, according to the study of different picking time, the recommended picking time of cold dew seeds in Hunan area is around October 10, while the best picking time of frost’s descent seeds is about October 30. The oil content of C. oleifera fruit in different geographical provenances is quite different. During the development of C. oleifera fruit, the cultivation and management of C. oleifera should be strengthened to increase the oil content of C. oleifera. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: The purpose of the study was to observe the effects of fenvalerate exposure on the semen quality of occupational workers. Materials and Methods: Thirty-two male workers who were exposed to fenvalerate and 46 male administrators in the office in the same pesticide factory were selected as the exposure group and internal control group, respectively, and 22 male administrators in a center for disease control served as the external control group. In order to evaluate the exposure levels, the concentration of fenvalerate, toluene and xylene in the ambient air of the work place in these three groups were monitored simultaneously for 3 consecutive days. Moreover, the amount of fenvalerate in individual sampling and dermal contamination were evaluated in the exposure group and external control group. After the semen was collected according to the standard method, the workers'' semen qualities were analyzed. Results: Concentration of fenvalerate in the exposure areas was 21.55×10−4 mg/m3. The fenvalerate concentration in individual samplings in the exposure areas was 0.11 mg/m3. The dermal contamination for workers in the fenvalerate exposure area was 0.05 mg/m3. Fenvalerate was not detected in individual samplings collected in external areas. Sperm motion parameters through routine semen analysis in the exposure group were decreased significantly, and the abnormality rate of viscidity and coagulation was increased significantly as compared with the internal and the external control groups (p<.05 or p<.01). Furthermore, sperm progression and beat cross frequency (BCF) (4.20±1.68 Hz) in the exposure group were also significantly lower than those in the external control group by computer-assisted sperm motility analysis (CASA) (p<.05). Conclusion: Occupational exposure to fenvalerate could affect the semen quality of the workers, but the conclusion warrants further complete investigation due to various limitations of the study. [Copyright &y& Elsevier]

This paper studied the effects of liquid-solid ratio, temperature, time and pH value on the extraction rate of tea saponin from the cake of Camellia oleifera seeds by using single factor experiment with the cake of Camellia oleifera seeds as the raw materials, and water as the extraction solvent, and orthogonal test was used to determine the optimal extraction process conditions. The results showed that the extraction ratio of tea saponin could reach up to 95.50% when the liquid-solid ratio was 11:1, extracting temperature of 80°C, extraction time of 6 h, and pH value of 9. [ABSTRACT FROM AUTHOR]