Effect of Different Nitrogen Forms and Concentrations on Yield and Quality of Fritillaria thunbergii / 中国实验方剂学杂志

Objective:To investigate the effect of different nitrogen forms and concentrations on yield and quality in Fritillaria thunbergii，and provide basis for improving scientific utilization of nitrogenous fertilizer and its introduction to Chongqing area. Method:The pot culture experiment was conducted to investigate the changes in growth，physiological and biochemical characteristics，soil factors，alkaloid content and yield of Fritillaria thunbergii under the ratio of nitrate nitrogen（NO3--N） to ammonium nitrogen（NH4+-N）of 15∶0（N1），12∶3（N2），7.5∶7.5（N3），3∶12（N4） and 0∶15（N5）. Result:As compared with no-nitrogen（CK） treatment group，the growth and quality of F. thunbergii were significantly improved by different nitrogen nutrition treatments，with differences among them.With the increase of ammonium nitrogen concentration：①plant height and the activity of superoxide dismutase（SOD） reached the maximum when the ratio of NO3--N to NH4+-N was 3∶12，increased by 9.27% and 206.62% respectively compared with the CK group，② the length and width of leaf，stem diameter，chlorophyll a，chlorophyll b，total chlorophyll content，the content of available P and organic matter，total alkaloid content and yield reach the maximum when the ratio of NO3--N to NH4+-N was 0∶15，increased by 14.02%，16.44%，13.68%，40.75%，45.31%，41.72%，77.70%，14.70%，24.61%/47.39% respectively compared with the CK group，with the increase of nitrate nitrogen concentration，③the leaf index，soluble protein content，peimisine content/yield，yield of peiminine and dry weight of bulbs reached the maximum when the ratio of NO3--N to NH4+-N was 7.5∶7.5，increased by 2.54%，5.92%，21.76%/54.55%，60.61% and 26.93%，respectively compared with the CK group，④the content of carotenoids，pigment and peiminine，the activity of peroxidase（POD） and catalase（CAT），the content/yield of peimine，both peimine and peiminine，both peimine，peiminine and peimisine，dry weight of bulbs reached the maximum when the ratio of NO3--N to NH4+-N was 12∶3，increased by 45.39%，45.31%，36.01%，271.38%，67.45%，39.82%/64.87%，38.90%/63.80%，37.03%/61.57%，20.29% respectively compared with the CK group. Conclusion:All the results indicated that a higher proportion of NH4+-N is beneficial to the growth of F. thunbergii，while NO3--N is beneficial to the accumulation of alkaloids and the growth of bulbs.Therefore，the combined application of ammonium and nitrate（NO3--N to NH4+-N ratio of 12∶3） is more effective than pure nitrate or pure ammonium applications to improve the yield and quality of F. thunbergii．

Correlation Analysis Between Bulb Quality and Rhizosphere Soil Factors of Fritillaria taibaiensis / 中国实验方剂学杂志

Objective::To explore the correlation between bulb quality and rhizosphere soil factors of Fritillaria taibaiensis of different origins and years, in order to provide theoretical basis for the high quality and safe production of F. taibaiensis. Method::Totally 11 samples of bulb and rhizospheric soil of F. taipaiensis of different origins and years were taken as the research objects. Available N, available P, available K, organic matter, pH and six soil enzyme activities in rhizosphere soils were determined by soil agrochemical analysis method. Peimisine and nine nucleosides in F. taibaiensis bulbs were determined by HPLC, and total alkaloid content was determined by UV. SPSS 22.0 software was used to analyze the correlation of the measured data. Result::There were significant differences in rhizosphere soil factors and bulb quality between F. taibaiensis of different origins and years (P<0.05). In terms of soil factors, the contents of available N, available K, organic matter and six soil enzyme activities in rhizosphere soil of wild varieties were higher than those of cultivated varieties, while the contents of available P and pH were lower than those of cultivated varieties. With the increase of growth years, the soil nutrient index of cultivated varieties showed different change trends, while that of wild varieties did not change significantly. However, most of the soil enzymes in both groups decreased in varying degrees. In terms of bulb quality, the contents of nine nucleosides and alkaloids in F. taibaiensis bulbs decreased with the increase of growth years, with larger change trends of cultivated varieties, while that of wild varieties was not significant. The contents of nucleosides and alkaloids in most cultivated varieties were higher than those in wild varieties. The correlation analysis showed certain correlations between soil factors in rhizosphere as well as soil factors and bulb quality. In general, soil nutrient status and bulb quality decreased with the increase of years. Conclusion::The quality of F. taibaiensis is mainly affected by its rhizosphere soil factors. In the process of field conservation and artificial cultivation, attention shall be paid to increase or decrease of the content of soil nutrients and their proportional relationship according to actual situations, so as to ensure the quality of F. taibaiensis.

Variation Pattern of Rhizospheric Soil Nutrient for Fritillaria taipaiensis / 中国实验方剂学杂志

Objective: To study the variation patterns of rhizospheric soil nutrient and the content of nutrient elements for Fritillaria taipaiensis,in order to provide the theoretical base for the soil improvement and balanced fertilization during the artificial cultivation. Method: Totally 14 samples of rhizospheric soil of Fritillaria taipaiensis from different origins and years were taken as the research objects. Total N,available N,total P,available P,total K,available K,organic matter,pH and 7 nutrient element contents (Ca,Mg,Na,Mn,Zn,Cu and Ni) were analyzed by the soil agrochemical analysis method combined with the atomic absorption spectrophotometry. SPSS 22.0 software was applied for data multiple comparison and correlation analysis. Result: The all results showed significant differences (PF. taipaiensis. The content of total N,available N,total P,available P and organic matter of rhizospheric soil collected from cultivated varieties decreased with the increase of years,and the content of total K,available K and pH decreased first and then increased. However,the soil physical and chemical properties of wild varieties had no obvious change with the increase of years. The content of Ca,Mg,Na and Cu of soil from cultivated varieties decreased with the increase of years,while the content of Mn decreased first and then increased. And Zn and Ni showed no significant change with the increase of years. Compared with cultivated varieties,the content of Ca,Mg,Na,Mn and Cu increased first and then decreased. The content of Zn and Ni showed no obvious change. In general,the rhizospheric soil nutrient and the content of nutrient elements for wild F. taipaiensis were superior to those of cultivated varieties. Conclusion: The third year is the turning point of F. taipaiensis growth. The rhizospheric soil nutrient and the content of nutrient elements decreased obviously after three years. Attention shall be given to the balanced fertilization,the improvement of soil quality and the prevention of the cropping during cultivation of F. taipaiensis.

Correlation between rhizospheric microorganisms distribution and alkaloid content of Fritillaria taipaiensis / 中国中药杂志

In order to reveal the relationship between the amount of soil microorganisms and the quality of Fritillaria taipaiensis, both cultivated and wild F. taipaiensis were collected from Chongqing, Wuxi at different stages of their growth as objects of the research. The mycorrhizal infection rate and colonization intensity, peimisine and total alkaloid content in bulbs, the amount of microorganisms and biomass carbon content in rhizospheric soil were all determined using common methods. The results showed that the typical arbuscular-vesicle roots were formed after the AM fungi infected the F. taipaiensis roots which were collected from different origins. The mycorrhizal infection rates were ranged from 78.74% to 98.68% and the colonization intensities were ranged from 13.29% to 37.06%. The rhizospheric microorganisms of F. taipaiensis showed abundant resources. The distribution rule of them in the rhizospheric soil was as follows: the amount of bacteria>the amount of actinomycetes>the amount of fungi. The rhizospheric bacteria, decomposition inorganic phosphorus bacteria, decomposition organic phosphorus bacteria, actinomycetes amount and the total number of microbes increased first and then decreased with the increase of years, while decomposition potassium bacteria showed decreasing trend and fungi showed gradual increasing trend. The soil microbial flora content in the soil changed from "bacterial type" with a high fertility to "fungal type" with a low fertility. The mass fraction of peimisine and total alkaloid content increased first and then decreased with the increase of over the years, the same trend of culturable rhizosphere soil bacteria and actinomycetes indicated that the growth years affected the quality of soil and medicinal materials on different levels. Therefore, the diversity of microbial communities in rhizosphere soil reduced with the increase of years leading to the continuous cropping obstacles and the destruction of medicinal quality of F. taipaiensis.

A comparative study of two methods of intruding overerupted upper molars / 口腔疾病防治

Objective@# To compare the clinical effects of the two methods of intruding overerupted molars by microscrews.@*Methods @#21 overerupted molars were selected and ramdomly divided into group A and group B. Group A was implanted with one microscrew anchorage at the side of the buccolingual tongue, and the force was produced by the tension spring. Group B was implanted with two microscrews combined with nickel - titanium fragments to lower the molars. The distances, velocities and microscrew anchorage failure rates were measured and compared between the two groups. @*Results @#Two methods can achieve significant depressing effect, however, the failure rate of micro-screws was different in the two methods. The failure rates of group A and group B were 27.3% and 5.0%, respectively. The average speed of group A was 0.37 mm / month, and group B was 0.33 mm / month.@*Conclusion@#Both microscrew anchorage methods can effectively intrude overerupted upper molars. The speed of intrusion with microscrews directly is faster than NiTi Segmental arch and microscrews, but the implant failure of microscrews is higher.