ABSTRACT
To ensure the safety of medications, it is vital to accurately authenticate species of the Apocynaceae family, which is rich in poisonous medicinal plants. We identified Apocynaceae species by using nuclear internal transcribed spacer 2 (ITS2) and psbA-trnH based on experimental data. The identification ability of ITS2 and psbA-trnH was assessed using specific genetic divergence, BLAST1, and neighbor-joining trees. For DNA barcoding, ITS2 and psbA-trnH regions of 122 plant samples of 31 species from 19 genera in the Apocynaceae family were amplified. The PCR amplification for ITS2 and psbA-trnH sequences was 100%. The sequencing success rates for ITS2 and psbA-trnH sequences were 81% and 61%, respectively. Additional data involved 53 sequences of the ITS2 region and 38 sequences of the psbA-trnH region were downloaded from GenBank. Moreover, the analysis showed that the inter-specific divergence of Apocynaceae species was greater than its intra-specific variations. The results indicated that, using the BLAST1 method, ITS2 showed a high identification efficiency of 97% and 100% of the samples at the species and genus levels, respectively, via BLAST1, and psbA-trnH successfully identified 95% and 100% of the samples at the species and genus levels, respectively. The barcode combination of ITS2/psbA-trnH successfully identified 98% and 100% of samples at the species and genus levels, respectively. Subsequently, the neighbor joining tree method also showed that barcode ITS2 and psbA-trnH could distinguish among the species within the Apocynaceae family. ITS2 is a core barcode and psbA-trnH is a supplementary barcode for identifying species in the Apocynaceae family. These results will help to improve DNA barcoding reference databases for herbal drugs and other herbal raw materials.
ABSTRACT
In order to study the effect elements of anthers opening-closing movement of Paris polyphylla var. yunnanensis, and its cell morphology regulatory mechanism. Anthers daily opening in the morning and closing in the evening and its corresponding ecological elements changes were recorded. Different light, temperature, humidity experiment and artificial rainfall experiment were designed to observe the effect on anthers opening-closing movement, paraffin sections were made to observe the cell morphology change when the anthers daily opening and closing. The result showed that the movement of anthers daily opening and closing was regulated by ecological elements. The overall trend was high temperature and strong light, low humidity was favorable for anther opening, and low temperature, weak light, high humidity was favorable for anther closing. In this experiment, the effect of these ecological elements on the movement of anthers opening from strong to weak was humidity, temperature, light. The effect of these ecological elements on the movement of anthers closing from strong to weak was light, humidity, temperature. The direct contact of the raindrops causes the rapid closing of the anthers in the rain. Observing the cell morphology change when anthers opening and closing, it was a pollen sac dehydration and water-absorption process, different light, temperature and humidity conditions induce different physiological activities in the cell, which caused the cell osmotic pressure change, eventually resulting in anther opening and closing movement. But anthers closing caused by the rain was a simple physical adjustment process, the raindrops fell on the anthers directly, which caused anthers soaked water and change of the cell osmotic pressure, then resulting in anther closing.
ABSTRACT
Objective: To investigate the genetic polymorphism of wild Anoectochilus roxburghii and its allied species by molecular marker and find out the genetic differences between them. Methods: Direct amplification of length polymorphism (DALP) was applied to evaluate the genetic variation of 18 populations of A. roxburghii and its allied species from different places. Results: Six pairs of primers were selected to detect 355 polymorphic loci in 18 populations, the percentage of polymorphic bands (PPB) was 100%, and the amplified average polymorphic locus by each pair of primers was 59.2. The percentage of PPB of 14 populations of A. roxburghii was 95.77%, its observed number of alleles (Na) was 1.2734, effective number of alleles (Ne) was 1.074, Nei's gene diversity (H) was 0.0562, Shannon's information index (I) was 0.0969, coefficient of gene differentiation (Gst) was 0.4230, and estimated gene flow (Nm) was 0.6819. Conclusion: The results indicate that A. roxburghii has larger genetic differentiation and lower gene flow among populations. Geographic isolation and wild resource loss may be the major causes of the limited gene flow.
ABSTRACT
A survey of 420 exposures of mammography was performed with the parameters recorded. Entrance skin air kerma (ESAK) was measured and the mean glandular dose (MGD) was calculated according to the Dance's formula. Correlation analysis showed that several factors could affect the MGD level. Mann-whitney test and Non-parametric ANOVA analyses were used to compare the MGD level grouped by view type and radiographic systems. No significant difference was found in MGD between the craniocaudal (CC) group and the mediolateral oblique (MLO) group. The MGD level was higher in the CR group than in the other two groups. MGD was positively correlated with the compressed breast thickness (CBT). MGD varied with the half value layer (HVL) and increased first then decreased. The mean MGD level in China is about 1.6 mGy and is lower than the guidance level in the International Basic Safety Standards (IBSS).
Subject(s)
Female , Humans , Middle Aged , China , Mammography , Radiation DosageABSTRACT
<p><b>OBJECTIVE</b>To analyze the fungal composition in Massa Medicata Fermentata based on culture dependent method and independent PCR-SSCP technique.</p><p><b>METHOD</b>Fungi were directly isolated from Massa Medicata Fermentata samples. The obtained strains were identified according to morphology and DNA sequence. Meanwhile the total fungal DNA was extracted from Massa Medicata Fermentata samples, the cultural independent PCR-SSCP technique based on β-tubulin gene were used to identify the mycobiota.</p><p><b>RESULT</b>According to cultural method, Aspergillus flavus and Rhizopus oryzae were present in Massa Medicata Fermentata samples, while A. flavus and A. niger were present in fried Massa Medicata Fermentata samples. In contrast, 5 species were obtained by PCR-SSCP technique, A. flavus was overlapped with fungal taxa derived from culture dependent method; A. ambiguu and A. s ivoriensis were dominant with relative abundance of 57% and 35% respectively, while the relative abundance of A. flavus was as low as 4%. None species was obtained from fried Massa Medicata Fermentata samples.</p><p><b>CONCLUSION</b>PCR-SSCP based on β-tubulin gene could distinguish fungi into species, culture dependent method combined with culture independent method could better understand the fungal composition associated with Massa Medicata Fermentata fermentation.</p>
Subject(s)
Fermentation , Fungi , Medicine, Chinese Traditional , Polymerase Chain Reaction , Methods , Polymorphism, Single-Stranded Conformational , Tubulin , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To provide the basic guidance for seed breeding and cross-breeding of Paris polyphylla var. yunnanensis.</p><p><b>METHOD</b>The floral behavior and pollinators were observed; 0.5% TTC solution was used for the pollen viability test and benzidine and -H2O2 was used for estimation of the stigma receptivity. The mating systems were tested by out crossing index (OC1), and pollination experiment was carried out by bagged and emasculated test in the field.</p><p><b>RESULT</b>Commonly, stigma lobes spread slightly, and anthers started presenting the pollen from the outer ring while the flower was just beginning to open. Consequently, the distance between the stigma and its own pollen was relatively far, this "floral behavior" may be conducive to outcrossing. Then the flower entered the later period, while the stigma lobes spread widely, anthers all split, and this "floral behavior" shortened the stigma and its own pollen's distance, which may be conducive to selfing. P. polyphylla was partly protogynous. Stigma life-span was about 10-12 d. After anther dehiscence, the pollen viability maintained about 10% within 2 days, and 20% within 10 days. The value of out crossing index (OC1) was 4. By pollination experiment and pollinators observed, P. polyphylla was self-compatible, but no capacity for autonomous self-fertilization; In natural circumstances, outcrossing fructification rate was low, and mainly anemophilous. Assisted selfing-fertilization fructification rate was higher, spider was the main pollinators.</p><p><b>CONCLUSION</b>P. polyphylla has a mixed mating system with self-pollination and cross-pollination characteristics. Floral behavior has important adaptive significance in avoiding female and male interference, outcrossing, and delayed selfing. P. polyphylla is ambophily (a combination of both wind and insect pollination), pollinators changes due to environment. Pollen limitation is the main cause of low fructification rate under natural conditions.</p>