Effect of Mirabilis jalapa (Linn.) Growth on Microbial Community in Bioremediation of Petroleum-contaminated Saline-alkali Soil

Microbial biomass and species in the rhizosphere soil of Mirabilis jalapa（Linn.）（the saline-alkali soil contaminated by total petroleum hydrocarbon（TPH））were studied with the technology of phospholipid fatty acids（PLFAs） analysis,to explore the effects of Mirabilis jalapa（Linn.） growth on the structure characteristics of microbial communities and degradation of TPH in the petroleum-contaminated salinealkali soil.The result showed that compared with the CK soil without Mirabilis jalapa（Linn.）,the kind change rates of PLFAs were 71.4%,69.2% and 33.3% in spring,summer and autumn,respectively,and the degradation of TPH increased by 47.6%,28.3%,and 18.9% in the rhizosphere soil in spring,summer and autumn,respectively.Correlation analysis was used to determine the correlation between the degradation of TPH and the soil microbial communities：77.8% of the microbial PLFAs showed positive correlation（the correlation coefficient r﹥0） with the degradation of TPH,and 55.6% of the PLFAs had high positive correlation with the degradation of TPH with a correlation coefficient r ≥0.8.In addition,the relative contents of SAT and MONO had high correlation with the degradation of TPH in the CK soil,and the correlation coefficients were 0.92 and 0.60,respectively;but in the rhizosphere soil,42.1% of the PLFAs had positive correlation with it,and only21.1% had high positive correlation with the degradation of TPH,the relative contents of TBSAT,MONO and CYCLO had moderate or low positive correlation with the degradation of TPH,and the correlation coefficients were 0.56,0.50 and 0.07 respectively.It was shown that the growth of mirabilis jalapa（Linn.） highly affected the microbial community structure and TPH degradation speed in the rhizosphere soil,providing a theoretical basis for the research on phytoremediation of petroleumcontaminated saline-alkali soil.

β-Islet cell regeneration potential of Mirabilis jalapa in hyperglycemic rats

Objective:To investigate the role of Mirabilis jalapa root extracts in restoration of glucose homeostasis in alloxan-induced hyperglycemic Wistar albino rats.Methods:Experimental hyperglycemic rats were treated daily with 200 and 400 mg/kg of Mirabilis jalapa extracts after initial fasting for 6 h.Two-hour postprandial glucose and changes in body weight were monitored during treatment.After 14 d,the rats were sacrificed and blood was collected for biochemical assessment of serum glucose and insulin levels,lipid profile,and oxidative stress markers.Histopathological examinations of harvested pancreas were also carried out.Results:Mirabilis jalapa root extracts at 200 and 400 mg/kg increased the body weight of hyperglycemic rats.Postprandial glucose levels of the extract-treated hyperglycemic groups progressively declined during treatment compared with the untreated hyperglycemic control group(P<0.05).The lipid profile indices of the untreated negative control group were significantly elevated(P<0.05),which were reversed by treatment with Mirabilis jalapa extracts.The remarkable increases in antioxidant enzyme activities and a significant decrease in malondialdehyde levels were observed in the hyperglycemic group treated with Mirabilis jalapa extracts.Mirabilis jalapa extracts also significantly increased serum insulin levels(P<0.05).In addition,histopathological examinations of the pancreas revealed a significant cell population within the islet nests of the extract-treated hyperglycemic groups.Conclusions:Mirabilis jalapa extract can restore glucose homeostasis and show hypoglycemic and hypolipidemic effects in hyperglycemic rats.Further studies are needed to verify the active components of the plant and the underlying mechanism of action in the future.

入侵植物紫茉莉的传粉生态学

入侵植物的繁殖策略是理解物种入侵机制的重要组成部分。紫茉莉(Mirabilis jalapa)是中国常见的外来入侵植物,在北方城市园林中广泛应用。以河北省张家口市为例,对紫茉莉的花部性状、开花动态、杂交指数、花粉-胚珠比、传粉生物、套袋试验等方面开展研究。结果表明,紫茉莉的交配方式为自交和异交共存,具有自交亲和性,偶尔需要传粉者。较高的环境温度可能影响紫茉莉的结实率。当前入侵阶段紫茉莉以自交为主,但交配系统是否发生转变受物种的入侵阶段和所处环境影响,紫茉莉的灵活交配机制可能是其在北方城市入侵成功的重要因素。这为从传粉生态学角度研究紫茉莉入侵机制和控制方法提供了参考。

不同有机肥料对紫茉莉生长及生理指标的影响

为了解不同有机肥料对紫茉莉(Mirabilis jalapa L.)生长发育的影响,选用不同有机肥处理对一年生紫茉莉进行试验研究,分析土壤养分含量与紫茉莉的生长发育指标在不同有机肥处理下的变化规律。结果表明,施加不同有机肥料均明显提高了土壤的养分含量,不同处理下土壤各养分含量整体变化趋势相同;施加有机肥料对植物长势及根系活力有明显的促进作用;施加有机肥料能提高紫茉莉的光合速率、降低蒸腾速率,有助于增强植物的抗逆性。