The biotypes and host shifts of cotton-melon aphids Aphis gossypii in northern China

Aphis gossypfi is a globally distributed species and therefore has a highly variable life cycle. Populations of A. gossypii in northern China exhibit greater genotypic diversity and a broader host range, yet the details of life cycles of different biotypes is still unclear. In this study, the Cytb and 16S gene regions of A. gossypfi collected from 5 common summer hosts and 4 primary hosts were analyzed. A total of 57 haplotypes were obtained from 1 046 individual A. gossyp# sequences. The sequence included 44 variable sites, 27 of which were parsimony informative sites and 17 of which were singleton variable sites. The most frequent 3 haplotypes were found in 896 individuals, representing a total of 85.7% of all individuals and 36 haplotypes were found in 1 individual. A neighbor-joining tree was constructed using 21 haplotypes that were found in more than 2 individuals. Considering the individual host plant, 5 biotypes were identified. Type 1 corresponded exactly to the cucurbit host-race and the other 4 biotypes were found as cotton host-races. Type 3 was the most abundant biotype in cotton fields in northern China.

Comparative Analysis of Population Genetic Structure in Bemisia tabaci(Gennadius) Biotypes B and Q Based on ISSR Marker

Bemisia tabaci （Gennadius） biotypes B and Q are two invasive biotypes in the species complex. The comparison of the population genetic structure of the two biotypes is of significance to show their invasive mechanism and to their control. The intersimple sequence repeats （ISSR） marker was used to analyze the 16 B-biotype populations and 4 Q-biotype populations worldwide with a Trialeurodes vaporariorum population in Shanxi Province, China, and a B. tabaci non-B/Qbiotype population in Zhejiang Province, China, was used as control populations. The analysis of genetic diversity showed that the diversity indexes of biotype Q including Nei＇s gene diversity index, Shannon informative index, and the percentage of polymorphic loci were higher than those of biotype B. The high genetic diversity of biotype Q might provide the genetic basis for the excellent ecological adaptation. Cluster analysis suggested that the ISSR could not be used in the phylogenetic analysis though it could easily distinguish the biotypes of B. tabaci. The difference of the population genetic structure between the biotype B and the biotype Q exists based on the ISSR marker. Meanwhile, the results suggested that the molecular marker has its limitation in the phylogenetic analysis among the biotypes of B. tabaci.

Comparative Morphology and Morphometry of Six Biotypes of Bemisia tabaci (Hemiptera: Aleyrodidae) from China

Morphology and morphometry of six biotypes （B, Q, Cv, ZHJ-1, ZHJ-2 and ZHJ-3） of Bemisia tabaci （Gennadius） from China on cotton plants were studied by using microscopes. Nymphal body sizes and characters were measured and observed, especially on the 4th instar （pupal case）, including the vasiform orifice, operculum, lingula, length and thickness of anterior and posterior wax margins, width of thoracic tracheal combs. Adult characters of both sexes were investigated including the body size, compound eyes, antennal segments, vasiform orifice, hind tarsi and genitals. The results indicated that differences of some morphological characters or morphometrics were significant among the six biotypes of B. tabaci in China： （1） Pupal sizes of the exotic biotypes （B and Q） were significantly larger than the indigenous biotypes with the following order as B〉Q〉ZHJ-I〉Cv〉ZHJ-3〉ZHJ-2; （2） for both male and female adults, sizes of all characters investigated in the invading biotypes （B and Q）, especially B, were much larger than those of the indigenous ones.

Bemisia tabaci Biotype Dynamics and Resistance to Insecticides in Israel During the Years 2008-2010

The sweetpotato whitefly Bemisia tabaci（Hemiptera：Aleyrodidae）is an extremely polyphagous insect pest that causes significant crop losses in Israel and worldwide.B.tabaci is a species complex of which the B and Q biotypes are the most widespread and damaging worldwide.The change in biotype composition and resistance to insecticide in Israel was monitored during the years 2008-2010 to identify patterns in population dynamics that can be correlated with resistance outbreaks.The results show that B biotype populations dominate crops grown in open fields,while Q biotype populations gradually dominate crops grown in protected conditions such as greenhouses and nethouses,where resistance outbreaks usually develop after several insecticide applications.While in previous years,Q biotype populations were widely detected in many regions in Israel,significant domination of the B biotype across populations collected was observed during the year 2010,indicating the instability of the B.tabaci population from one year to another.Reasons for the changing dynamics and the shift in the relative abundance of B.tabaci biotype,and their resistance status,are discussed.

Studies on the Host Biotypes and Its Cause of Cotton Aphidin Nanjing,China

The fitness of cotton aphid, Aphis gossypii Glover, on different host plants was studied. The results showed that the cotton aphid population in Nanjing formed host preference bio-types on cucumber and cotton. The aphids from cotton and cucumber could not inter-transplant successfully between the two host plants. The apterous and alate offspring of stem mother from hibiscus could not survive, reproduce and form population normally when they were transplanted to cucumber and water melon, but they could form normally when transplanted to cotton and muskmelon. There was no significant difference between the stylet length of cotton aphids from cucumber and cotton, so the stylet length was not the cause of the host preference. When the aphids originated on hibiscus were transplanted to cotton, water melon and muskmelon, the stylet could reach host phloem to absorb host plant’s nutrients, but it couldn’t when transplanted to cucumber. Cotton aphid can feed on muskmelon without secretion of water-soluble saliv

Species and Biotype Analysis of Brucella Strains Isolated from Cattle and Sheep in Xinjiang

[ Objective] The paper aimed to understand the epidemiological characteristics of Brucella strains in Xinjiang and then provide an available integrated measure to prevent and control brucellosis. [ Method ] Eleven suspected Brucella strains were isolated by traditional methods, which were further identified by AMOS-PCR assay. Conventional biochemical tests were carried out to identify the biological subtype of sheep Brucella. [ Result] Nine strains were all B. meliten- s/s, and biological test indicated that all of them were B. melitensis biotype 3. [ Conclusion] B. melitensis biotype 3 was the predominant strain of Brucella in Xin- jiang, and AMOS-PCR assay could be applied safely and quickly as an assistant tool to detect Brucella. The results of molecular epidemiology laid a foundation for updating prevention and control strategy against brucellosis in Xinjiang.

Impact of Rice Stem Borers and Identification of <i>Orseolia oryzivora</i>Harris &Gagné, 1982 (Diptera: Cecidomyiidae) Biotypes in the Southern Cameroon

The study compares the impact due to rice stem borers in two sites (Yaoundé and Ntui). It also shows the diversity of the African Rice Gall Midge (AfRGM) biotypes in southern Cameroon (Santchou, Ndop, Tonga, Ebolowa, Ba?gom, Yaoundé and Ntui). The New Rice for Africa (NERICA) varieties 3, 8, 9 and 13 sown in Ntui were less attacked than those sown in Yaoundé. At both sites, damages ranged from 0.78% to 2.7%. In terms of diversity, the main stem-borer species were O. oryzivora, Diopsis apicalis, D. longiconis and Chilo zacconius. Molecular analyses of Orseolia oryzivora larvae collected in the localities of Santchou, Ndop, Tonga, Ebolowa, Ba?gom and Yaoundé showed the existence of more than one O. oryzivora biotype in southern Cameroon’s rice basins.

Gingival biotype: The probe test utility

Purpose: To evaluate the relevance of the probe test in classifying the gingival biotype and to determine if differences exist between maxillary and mandibular gingival biotypes in the same patient. Materials and Methods: 53 subjects were included. The gingival thickness was evaluated as thick or thin. This evaluation was based on the transparency of the periodontal probe through the gingival margin while probing the sulcus. In another hand, 124 clinicians were asked to identify the gingival biotype in the same 53 subjects based on visual inspection on pictures. For each examiner, the accuracy in identifying the gingival biotype was assessed using the percentage of cases correctly identified. Results: the percentile of agreement is greater than 70% in maxilla as well as in mandible. An imbalance was observed on the maxillary pictures concerning the gingival biotype and on the thin biotype between maxilla and mandible despite there being no statistical difference (p < 0.0001). The percentile of agreement is quite similar in the mandible for both thin (74%) and thick (70%) gingival biotypes. Agreement between mandibular probe and maxilla probe results demonstrates a weak percentile of agreement of gingival biotypes between maxillary and mandibular anterior teeth (57%). Conclusion: The use of probe transparency through the gingival margin is an accurate and simple method for gingival biotype diagnosis to discriminate a thin gingival from a thick gingival. Furthermore, individualizing the gingival biotype for each of the arches appears to be a new outcome that needs further investigation.

Prevalence of Gingival Biotype in a Syrian Population and Its Relation to Tooth Shapes: A Cross-Sectional Study

Background: Gingival biotype is one of the most important factors that impede success in dental treatments;it affects the outcomes of periodontal surgery, and restorative treatments. Researchers classified gingival biotypes into thin biotype and thick biotype. It is crucial to identify tissue biotype before treatment. Aim of Study: To determine the prevalence of gingival biotypes in a Syrian population, in addition, to study the distribution of gingival biotypes according to gender and tooth shape. Material and Methods: This cross sectional study included 500 volunteers (300 males and 200 females) from the patients who had visited the department of periodontology-dental faculty at Damascus University. Gingival thickness was assessed to determine the gingival biotype for the maxillary central incisors using the direct measurement technique (Trans-gingival probing). Shapes of the maxillary incisors were recorded. A written informed consent was taken from each patient. Statistical analysis was done using test k2 p < 0.05. Results: The mean age was 26.8 ± 4.4 years. Thick gingival biotype was detected in 58.4% of the sample and most of patients are men while the prevalence of thin gingival biotype was 41.6% of the sample. It was also observed that patients with thin gingival biotype had triangular tooth shape in 99.5% (p < 0.05). Conclusion: Thick gingival biotype was observed to be more prevalent in a Syrian population than thin biotype. Most Syrian males had thick gingival biotype with square tooth shape while females had thinner biotype and triangular tooth shape.

Effects of Crown Lengthening on Bi, PLI and PD Levels in Patients with Different Periodontal Biotypes

Objective:To investigate the effect of crown lengthening on patients with different periodontal biological types.Methods:60 patients with different periodontal biotypes treated in our hospital from May 2017 to February 2019 were retrospectively analyzed.According to the different periodontal biotypes,the above-mentioned patients were further divided into control group(thin fan type,30 cases)and observation group(thick flat type,30 cases).The periodontal probing depth(PD),plaque index(PLI),bleeding index(BI)and gingival margin position at 1 week,1 month,2 months and 3 months after operation were compared between the two groups.Results:The PD,Bi and PLI values of the two groups after treatment were lower than those before treatment(P<0.05);There was no significant difference in gingival margin position between the two groups after 1 week to 1 month and 1 month to 2 months(P>0.05);After 2 months to 3 months of treatment,the gingival margin distance of the observation group was larger than that of the control group,and the difference was statistically significant(P<0.05).Conclusion:Crown lengthening can effectively improve the periodontal indexes of different periodontal biotypes,and the gingival margin of thick and flat type patients moves more toward the crown.

Measurement and Clinical Significance of Gingival Biotype in Anterior Teeth

The morphological characteristics of periodontal tissue and tooth tissue in gingival biotype are one of the indicators reflecting the individual differences of periodontal tissue in patients.Gingival biotypes of anterior teeth are often related to the prognosis of smile aesthetic treatment,which is one of the reference indexes for predicting the success rate of aesthetic treatment such as restoration,implant,periodontal,orthodontic and so on.Gingival biotypes have individual differences,so different gingival biotypes have different responses to different external stimuli.In the current clinical work,the correct evaluation of gingival biotype,especially the accurate measurement of gingival thickness,is the basis of reasonable choice of treatment and prognosis evaluation.

国产MALDI-TOF MS系统Smart MS 5020对临床微生物的鉴定性能评估

目的评估珠海迪尔Smart MS 5020型基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)系统及其2630种数据库(以下简称Smart MS 5020系统)对临床微生物的鉴定能力。方法共纳入2016—2020年浙江大学医学院附属第二医院留存的临床分离菌株913株,覆盖18个属52个种或复合群。采用直接涂抹法进行鉴定,比对仪器为德国布鲁克Biotyper MS系统及其DB2969数据库(以下简称Biotyper MS),对于两台质谱仪不一致的鉴定结果,采用16S rRNA扩增测序作为判定的金标准。针对复合群(鲍曼不动杆菌复合群、阴沟肠杆菌复合群以及肺炎克雷伯菌复合群),采用二代测序的鉴定结果作为金标准,统计学方法采用卡方检验。选取13株室内质控菌株作为重复性评估的检测样本,每株菌在Smart MS 5020系统上平行检测3次,判断其鉴定结果的一致性。结果对913株临床菌株,Biotyper MS系统种水平鉴定准确率为100%(913/913,95%CI:99.48%~99.58%),Smart MS 5020系统种水平鉴定准确率为99.78%(911/913,95%CI:99.12%~99.20%),2株表皮葡萄球菌鉴定为柯氏葡萄球菌;在临床微生物的鉴定能力方面,2种方法差异无统计学意义(P>0.05)。重复性评估结果显示,Smart MS 5020系统对13株室内质控菌株的鉴定结果完全一致。结论Smart MS 5020系统对临床常见微生物有很好的鉴定能力,包括复合群的鉴定能准确鉴定到复合群,对一些难区分菌如嗜血杆菌、链球菌等均能准确鉴定,但对复合群内具体种的细分能力有限,需要结合分子生物学、血清学或其他补充实验来准确鉴定。

Responses of Detoxifying, Antioxidant and Digestive Enzyme Activities to Host Shift of Bemisia tabaci (Hemiptera: Aleyrodidae)

The polyphagous B-biotype of Bemisia tabaci （Gennadius） has demonstrated a high capacity to adapt to numerous hosts from diverse plant families. To illustrate induced responses by the host plant, biochemical research on eight plant-insect interaction correlative enzymes, representing detoxifying, antioxidant and digestive pathways, were investigated. Transferring whitefly adults to Zhongmian 23 from the pre-adapted host Zhongmian 41 induced activities of carboxylesterase （by 1.80-fold）, glutathione S-transferase （by 3.79-fold）, proteinase （by 1.62-fold） and amylase （by 2.41-fold） activities, hut decreased polyphenol oxidase （by 1.89-fold） and peroxidase （by 1.88-fold）. However, transferring whitefly adults to the favorite host abutilon from Zhongmian 41 was associated with increased activities of cytochrome P450 monooxygenase （by 1.61-fold） and amylase （by 1.42-fold）, and decreased activities of polyphenol oxidase （by 2.96-fold） and peroxidase （by 2.07-fold）. Our results, together with previous studies, proved that multiple pathways are involved in coping with host shifts by polyphagous herbivores, and the taxonomic status and preference of the host transferred would affect which pathway would be induced. These results would represent a key challenge in developing long-term sustainable insect control strategies.

Sequence Analysis of mtDNA CO/Gene and Molecular Phylogeny of Different Geographical Populations of Bemisia tabaci (Gennadius)

Bemisia tabaci(Gennadius) is a serious pest in many cropping systems worldwide and occurs in different biotypes. ThemtDNA COI gene of the 12 Bemisia tabaci (Gennadius) populations from different regions and countries were analyzed.Based on mtDNA COI sequences, their biotypes were characterized and phylogenetic relationships among thesepopulations were established with the method of UPGMA. The results indicated the genetic similarity between thosepopulations from Beijing, Zhengzhou, Zaozhuang, Nanjing, Shanghai, Haikou, and the B-biotype populations fromCalifornia, Texas, Arizona reached 99.8-100%, which meant the nation-wide infested populations of B.tabaci in China inrecent years were B-biotypes. Another population collected from Kunming of Yunnan Province showed very high similaritywith Q-biotype B.tabaci from Spain and Morocco, which meant the Kunming population was Q-biotype. This is the firstreport on the invasion of Q-biotype into China.

Periodontally accelerated osteogenic orthodontics with platelet-rich fibrin in an adult patient with periodontal disease:A case report and review of literature

BACKGROUND In the clinical scenario,adult patients with periodontal diseases and dental malformation,characterized by dental crowding in lower anterior teeth with the thin biotype,often require orthodontic treatment.This case report aimed to evaluate the clinical and radiographic outcomes of periodontally accelerated osteogenic orthodontics(PAOO)combined with autologous platelet-rich fibrin(PRF)in an adult patient with class I malocclusion along with dental crowding,a thin periodontal biotype,and buccal plate deficiency.CASE SUMMARY A 32-year-old female complaining of dental crowding and gingival bleeding was referred to the orthodontic clinic.The patient underwent periodontal risk assessment prior to orthodontic treatment.She was diagnosed with a high risk of gingival recession due to dental crowding,root prominence,loss of buccal plates,and a thin gingival tissue biotype.The treatment regimen included PAOO combined with autologous PRF for alveolar augmentation and interproximal enamel reduction for moderate dental crowding.Clinically,PAOO-assisted orthodontic tooth movement in this case showed enhanced periodontium remodeling.Radiographic outcomes also showed statistically significant improvements(P<0.01)in the mandibular buccal alveolar bone.CONCLUSION This case report suggests the combination of autologous PRF with PAOO to enhance bone augmentation and long-term tissue support in adult orthodontic patients with periodontal disease.

cDNA Cloning of Heat Shock Protein Genes and Their Expression in an Indigenous Cryptic Species of the Whitefly Bemisia tabaci Complex from China

Thermal adaptation plays a fundamental role in shaping the distribution and abundance of insects,and heat shock proteins（Hsps）play important roles in the temperature adaptation of various organisms.To better understand the temperature tolerance of the indigenous ZHJ2-biotype of whitefly Bemisia tabaci species complex,we obtained complete cDNA sequences for hsp90,hsp70,and hsp20 and analyzed their expression profiles under different high temperature treatments by real-time quantitative polymerase chain reaction.The high temperature tolerance of B.tabaci ZHJ2-biotype was determined by survival rate after exposure to different high temperatures for 1 h.The results showed that after 41°C heat-shock treatment for 1 h,the survival rates of ZHJ2 adults declined significantly and the estimated temperature required to cause 50% mortality（LT50）is 42.85°C for 1 h.Temperatures for onset（Ton）or maximal（Tmax）induction of hsps expression in B.tabaci ZHJ2-biotype were 35 and 39°C（or 41°C）.Compared with previous studies,indigenous ZHJ2-biotype exhibits lower heat temperature stress tolerance and Ton（or Tmax）than the invasive B-biotype.

Isolation and Identification of Fusarium Wilt Pathogens from Bitter Gourd in Hainan Province

In order to isolate and identify the pathogens causing Fusarium wilt in bitter gourd in Hainan Province, China, four bitter gourd plants exhibiting symptoms of Fusarium wilt were collected from Tunchang County, Hainan Province. Four pathogen strains （HNTC-01, HNTC-02, HNTC-03 and HNTC-04） were isolated from the four plants, and identified via morphological observation and molecular techniques. The results showed that HNTC--01, HNTC-03 and HNTC-04 were F. oxysporum, while HNTC-02 was F. graminearum. The tests on pathogenicity and host specificity showed that HNTC-01, HNTC-03 and HNTC-04 were F. oxysporum Schl. f. sp. momordicae. Phylogenetic analysis revealed that HNTC-01, HNTC-03, HNTC-04 were clustered together with 14 strains of F. oxysporum, and HNTC-02 was clustered together with six strains of F. graminearum. In addition, rDNA-ITS region can be used to distinguish different Fusarium species, but can not be used to distinguish different biotypes within a Fusarium species. This study could provide a scientific basis for the diagnosis and prevention of wilt in bitter gourd.

An update on Gardneralla vaginalis associated bacterial vaginosis in Malaysia

Objective: To update the status of Gardnerella vaginalis(G. vaginalis) as a causative agent of bacterial vaginosis(BV) in Malaysia and to define its epidemiology, metronidazole resistance and virulence properties.Methods: It is a single-centre(Gynaecology clinic at the Hospital Kuala Lumpur,Malaysia) prospective study with laboratory-based microbiological follow up and analyses. Vaginal swabs collected from the patients suspected for BV were subjected to clinical BV diagnosis, isolation and identification of G. vaginalis, metronidazole susceptibility testing, vaginolysin and sialidase gene PCR, Piot's biotyping and amplified ribosomal DNA restriction analysis genotyping.Results: Among the 207 patients suspected for BV, G. vaginalis was isolated from 47 subjects. G. vaginalis coexisted with Trichomonas vaginalis and Candida albicans in 26 samples. Three G. vaginalis isolates were resistant to metronidazole. Biotyping revealed 1 and 7 as the common types. Amplified ribosomal DNA restriction analysis genotype II was found to be more common(n = 22; 46%) than I(n = 12; 25.53%) and III(n = 13;27.6%). All genotype I and III isolates carried the sialidase gene, while 91.6% and 84.6%contained the vaginolysin gene. Genotype I was significantly associated with postgynaecological surgical complications and abortions(P = 0.002).Conclusions: The existence of pathogenic G. vaginalis clones in Malaysia including drug resistant strains should not be taken lightly and needs to be monitored as these may bring more complications especially among women of child bearing age and pregnant women.

Nucleic Acid Determination and Risk Assessment of Brucella in Milk Products

Brucellosis is a worldwide zoonosis caused by Brucella, which poses great threat to human health. Totally 234 milk samples from a scale dairy farm were amplified by nested PCR, and the pathogens were further separated. The results showed that a DNA band of 419 bp was amplified from 18 out ot＂234 milk samples. Among 18 positive milk samples, nine samples amplified the DNA band of 535 bp, which were B. su/s ; one sample amplified the DNA bands of 535 bp and 285 bp, which was the mixture of B. su/s and B. bov/s. The results laid a foundation for prevention and control of brucellosis.