Identification of a major QTL for Hessian fly resistance in wheat cultivar‘Chokwang’

The Hessian fly(HF,Mayetiola destructor)is one of the destructive pests of wheat(Triticum aestivum L.)worldwide.Resistant cultivars can effectively minimize wheat damage due to this insect pest.To identify new quantitative trait loci(QTL)for HF resistance,a population of recombinant inbred lines(RILs)was developed from a cross between the HF-resistant wheat cultivar‘Chokwang’and susceptible wheat‘Ning 7840’,and phenotyped for responses to HF attack.A linkage map was constructed using 1147 single nucleotide polymorphism(SNP)markers generated from genotyping-by-sequencing(GBS).One major QTL,QHf.hwwg-6 BS,for HF-resistance was identified on chromosome arm 6 BS,which explained up to84.0%of the phenotypic variation and was contributed by Chokwang.Two RILs showed recombination in the candidate interval of QHf.hwwg-6 BS,which delimited QHf.hwwg-6 BS to a 4.75 Mb physical interval between 6,028,601 bp and 10,779,424 bp on chromosome arm 6 BS of IWGSC Chinese Spring reference genome Ref Seq v2.0.Seven GBS-SNPs in the candidate interval were converted into Kompetitive allele specific polymerase chain reaction(KASP)markers.Two of them,KASP-6 B112698 and KASP-6 B7901215,were validated in a U.S.winter wheat panel.KASP-6 B112698 was nearly diagnostic,thus can be used to screen QHf.hwwg-6 BS and pyramid it with other resistance genes in breeding programs.

Performance of parasitoid Aphidius giftiensis Ashmead parasitizing Myzus persicae fed on artificial media

Aphidius gifuensis Ashmead is an economically important aphid parasitoid,particularly for pest Myzus persicae.The aim of the study was to feed M.persicae using a formulated artificial medium instead of tobacco to maintain parasitoid A.gifuensis in winter.The development,survival and reproduction of M.persicae fed with four artificial media(AM1-AM4),as well as the parasitism,emergence and longevity of A.gifuensis when reared on F3 M.persicae fed with AMI,were assessed.Over 15 days of the study,the survival rates of A.gifuensis for the AM1 and AM2 treatments were significantly greater than those for the AM3 and AM4 treatments.The highest fecundity of F,A.gifuensis females was observed on AM1 feeding.No differences were noted in survival rate,development or nymph production between F:and F,M.persicae fed with AM1.No differences were recorded in the number of mummies,parasitism rate,adult Iongevity or proportion of A.gifuensis females between Treatment I(4.gifuensis parasitizing AM1-reared M.persicae)and the control.However,the emergence rate of Treatment I was lower than that of the control.The rearing of.A.gifuensis on M.persicae fed with an artificial medium was found to be a feasible proposition.This could save time,space and cost compared with traditional production methods.

Puccinia triticina effector protein Pt_21 interacts with wheat thaumatin-like protein TaTLP1 to inhibit its antifungal activity and suppress wheat apoplast immunity

Puccinia triticina(Pt), as the causal agent of wheat leaf rust, employs a plethora of effector proteins to modulate wheat immunity for successful colonization. Understanding the molecular mechanisms underlying Pt effector-mediated wheat susceptibility remains largely unexplored. In this study, an effector Pt_21 was identified to interact with the apoplast-localized wheat thaumatin-like protein TaTLP1 using a yeast two-hybrid assay and the Pt_21-TaTLP1 interaction was characterized. The interaction between Pt_21 and TaTLP1 was validated by in vivo co-immunoprecipitation assay. A TaTLP1 variant,TaTLP1C71A, that was identified by the site-directed mutagenesis failed to interact with Pt_21. Pt_21was able to suppress Bax-mediated cell death in leaves of Nicotiana benthamiana and inhibit TaTLP1-mediated antifungal activity. Furthermore, infiltration of recombinant protein Pt_21 into leaves of transgenic wheat line overexpressing TaTLP1 enhanced the disease development of leaf rust compared to that in wild-type leaves. These findings demonstrate that Pt_21 suppresses host defense response by directly targeting wheat TaTLP1 and inhibiting its antifungal activity, which broadens our understanding of the molecular mechanisms underlying Pt effector-mediated susceptibility in wheat.

Transgenic expression of TaTLP1, a thaumatin-like protein gene, reduces susceptibility to common root rot and leaf rust in wheat

Thaumatin-like protein (TLP) plays an important role in combating plant pathogen infection.Common root rot caused by Bipolaris sorokiniana and leaf rust caused by Puccinia triticina (Pt) are major fungal diseases in wheat.The disease responses of TaTLP1-overexpressing transgenic lines (TaTLP1-OE) were evaluated after inoculation with each pathogen.The TaTLP1-OE lines had no apparent differences in tiller number and 1000-kernel weight from the wild type Jinan Wheat No.1 (JW1),whereas resistance to leaf rust and common root rot was improved,resulting from activated peroxidase and b-1,3-glucanase after B.sorokiniana infection,and reactive oxygen species-related genes were upregulated in Ta TLP1-OE lines after Pt infection.These results indicated that stable expression of TaTLP1 increased resistance against both diseases.

Imported parasitic diseases in China's Mainland:current status and perspectives for better control and prevention

Background:The high prevalence of parasitic diseases leads to millions of deaths and disabilities each year in developing countries.China has also been greatly affected by parasitic infections,including filariasis,leishmaniasis,malaria,schistosomiasis,and soil-transmitted nematodosis.However,the situation in China improved dramatically after comprehensive parasitic disease control efforts were strengthened,leading to the elimination of filariasis in 2006 and to significant control over other diseases.However,imported parasitic disease cases are inevitable,and such cases have increasingly been reported as a result of enhanced globalization and international or regional cooperation.These imported diseases represent a major obstacle to the elimination of several parasitoses,such as malaria.Main text:This paper reviews imported cases of parasitic diseases in China's Mainland,particularly malaria and schistosomiasis,based on data reported separately by the Chinese annual reports and from other published papers.We summarize the new challenges that face parasitic disease control efforts in China's Mainland and perspectives regarding better control.We argue that both the provision of professional education and updated training for medical care personnel and the management and surveillance of people entering China are essential.We recommend that Chinese migrant workers should be considered a priority group for health education and that public awareness of imported diseases should be emphasized.Furthermore,we underscore the importance of investigating the distribution of introduced/potential vectors,parasite susceptibility,and improvements in diagnostic techniques and drug stocks.Conclusions:Imported cases have become the main challenge to the elimination of several parasitoses,such as malaria and schistosomiasis,in China's Mainland.China should act to meet these challenges,which are closely associated with national biological safety.

Insecticidal Activity of Crystals and Spores of Purified Bacillus thuringiensis 00-50-5 Strain against Trichoplusia ni Hubner

[ Objective] The paper was to study pathogenic mechanism and action mode of Bacillus thuringiensis （Bt） 00-50-5 strain against Trichoplusia ni Hub- ner. [Method] The crystals and spores of B. thuringiensis 00-50-5 strain were first isolated and purified, and their insecticidal activities against T. ni were com- pared. [ Result] Either the mixture of pure crystals and pure spores of 00-50-5 strain, or only pure crystals could kill T. n/larvae under the concentration of 100 p.g/mL after 48 h, and the mortality rate reached 100% ; pure spores could not kill the larvae. Determination results of median lethal concentration showed that in- secticidal activity of pure crystal of Bt 00-50-5 strain （LGs0 =0.32 p~/mL） was higher than the mixture of crystals and spores （LCs0 =0.48）, but the insecticidal acti^ty of pure spores was very low （LC50 〉 500.00）. Therefore, the crystals were primarily responsible for causing death of larvae. [ Conclusion] The paper provides theoretical basis for application of Bt 00-50-5 strain.

Pathogenicity of Cell Wall Degrading Enzymes Produced by Botryodiplodia theobromae Pat. against Mangoes

[ Objective ] This study aimed to confirm the roles of cell wall degrading enzymes （CWDEs） produced by Botryodiplodia theobromae Pat. in the infec- tion of mango fruits. [ Method] Change of activities of five types of CWDEs produced by B. theobromae Pat. were studied under both in vitro culture and inocula- tion conditions, along with the pathogenicity and the ability of producing CWDEs of four post-harvest fangal pathogens（B, theobromae Pat. , Colletotrichum gloeos- porioides Penz. , Phomopsis mangiferae Ahmad and Dothiorella dominicana Pet. et Cif. ） which cause stem-end rot of mangoes. [ Result] B. theobromae Pat. was a- ble to produce polygalacturonase（PG）, pectinmethylgalacturonase（PMG）, polygalacturonic acid trans-eliminase （PGTE）, pectin methyltrans-eliminase （PMTE） and cellulase （ Cx. ） under both in vitro culture and inoculation conditions, of which activities of PG, Cx and PMG were significantly higher in than that in either PGTE or PMTE. Among three primary CWDEs, the peak of activities of PG and Cx appeared earlier and that of PMG occured later. The pathogenicity of B. theo- bromae Pat. was significantly higher than that of any other three pathogens; it is the same with the abilities of producing pectinase. [ Conclusion] This paper pro- vides theoretical bases for further exploring the mechanism of host-pathogen interaction and decreasing the post-harvest loss of mango fruits.

Snail-borne parasitic diseases:an update on global epidemiological distribution,transmission interruption and control methods

Background:Snail-borne parasitic diseases,such as angiostrongyliasis,clonorchiasis,fascioliasis,fasciolopsiasis,opisthorchiasis,paragonimiasis and schistosomiasis,pose risks to human health and cause major socioeconomic problems in many tropical and sub-tropical countries.In this review we summarize the core roles of snails in the life cycles of the parasites they host,their clinical manifestations and disease distributions,as well as snail control methods.Main body:Snails have four roles in the life cycles of the parasites they host:as an intermediate host infected by the first-stage larvae,as the only intermediate host infected by miracidia,as the first intermediate host that ingests the parasite eggs are ingested,and as the first intermediate host penetrated by miracidia with or without the second intermediate host being an aquatic animal.Snail-borne parasitic diseases target many organs,such as the lungs,liver,biliary tract,intestines,brain and kidneys,leading to overactive immune responses,cancers,organ failure,infertility and even death.Developing countries in Africa,Asia and Latin America have the highest incidences of these diseases,while some endemic parasites have developed into worldwide epidemics through the global spread of snails.Physical,chemical and biological methods have been introduced to control the host snail populations to prevent disease.Conclusions:In this review,we summarize the roles of snails in the life cycles of the parasites they host,the worldwide distribution of parasite-transmitting snails,the epidemiology and pathogenesis of snail-transmitted parasitic diseases,and the existing snail control measures,which will contribute to further understanding the snail-parasite relationship and new strategies for controlling snail-borne parasitic diseases.

Design of a highly potent GLP-1R and GCGR dual-agonist for recovering hepatic fibrosis

Currently, there is still no effective curative treatment for the development of late-stage liver fibrosis. Here, we have illustrated that TB001, a dual glucagon-like peptide-1 receptor/glucagon receptor(GLP-1 R/GCGR) agonist with higher affinity towards GCGR, could retard the progression of liver fibrosis in various rodent models, with remarkable potency, selectivity, extended half-life and low toxicity. Four types of liver fibrosis animal models which were induced by CCl_(4), a-naphthyl-isothiocyanate(ANIT), bile duct ligation(BDL) and Schistosoma japonicum were used in our study. We found that TB001 treatment dose-dependently significantly attenuated liver injury and collagen accumulation in these animal models. In addition to decreased levels of extracellular matrix(ECM) accumulation during hepatic injury, activation of hepatic stellate cells was also inhibited via suppression of TGF-β expression as well as downstream Smad signaling pathways particularly in CCl_(4)-and S. japonicum-induced liver fibrosis. Moreover, TB001 attenuated liver fibrosis through blocking downstream activation of proinflammatory nuclear factor kappa B/NF-kappa-B inhibitor alpha(NFκB/IKBa) pathways as well as cJun N-terminal kinase(JNK)-dependent induction of hepatocyte apoptosis. Furthermore, GLP-1 R and/or GCGR knock-down results represented GCGR played an important role in ameliorating CCl_(4)-induced hepatic fibrosis. Therefore, TB001 can be used as a promising therapeutic candidate for the treatment of multiple causes of hepatic fibrosis demonstrated by our extensive pre-clinical evaluation of TB001.

Effects of selected insecticides on Diadegma semiclausum（Hymenoptera： Ichneumonidae） and Oomyzus sokolowskii （Hymenoptera： Eulophidae）, parasitoids of Plutella xylostella （Lepidoptera： Plutellidae）

Field doses of six selected insecticides were tested against the immature(pupae) and mature (adult) stages of Diadegma semiclausum (Hellen) and Oomyzus sokolowskii(Kurdjumov), parasitoids of the diamondback moth, Plutella xylostella (L.). Effects of contacttoxicity (direct spraying) of the six insecticides on emergence of parasitoids were found negligibleon both species except permethrin which caused 37.5% mortality. All adults of both parasitoidspecies died 24 hours after exposure to chlorfenapyr, emamectin benzoate and permethrin. Incontrast, the three insect growth regulators (IGRs), chlorfluazuron, flufenoxuron and teflubenzuron,were found harmless to both species, and adult mortality of both parasitoid species was 0—16.7%.However, parasitism by the females of both parasitoid species was severely impaired when the femaleswere offered the three IGR diluted solutions for 24 hours. Effects of oral toxicities of the IGRson longevity of both parasitoids after 12 hours exposure were found to be significantly differentbetween males and females. Compatibility of tested insecticides with D. semiclausum and O.sokolowskii and integration of compatible insecticides with these parasitoids in integrated pestmanagement programs of crucifers are discussed.

Zoonotic parasites carried by invasive alien species in China

Background:The invasive alien species may lead to great environmental and economic crisis due to its strong capability of occupying the biological niche of native species and altering the ecosystem of the invaded area.However,its potential to serve as the vectors of some specific zoonotic pathogens,especially parasites,has been neglected.Thus,the damage that it may cause has been hugely underestimated in this aspect,which is actually an important public health problem.This paper aims to discuss the current status of zoonotic parasites carried by invasive alien species in China.Main body:This review summarizes the reported zoonotic parasites carried by invasive alien species in China based on the Database of Invasive Alien Species in China.We summarize their prevalence,threat to human health,related reported cases,and the roles of invasive alien species in the life cycle of these parasites,and the invasion history of some invasive alien species.Furthermore,we sum up the current state of prevention and control of invasive alien species in China,and discuss about the urgency and several feasible strategies for the prevention and control of these zoonoses under the background of booming international communications and inevitable globalization.Conclusions:Information of the zoonotic parasites carried by invasive alien species neither in China or worldwide,especially related case reports,is limited due to a long-time neglection and lack of monitoring.The underestimation of their damage requires more attention to the monitoring and control and compulsory measures should be taken to control the invasive alien species carrying zoonotic parasites.

Parasitology should not be abandoned:data from outpatient parasitological testing in Guangdong,China

Over the past six decades,the Chinese government made parasitoses with a high disease burden,including soiltransmitted nematode infections,malaria,leishmaniasis,filariasis,and schistosomiasis,a public health priority because they were seen to be crucial impediments to the development of rural areas.As a result,these debilitating parasitic diseases that used to be widely prevalent have been well controlled or eliminated.Consequently,less attention has been paid to parasitic infection during the rapid development of the economy,especially in developed areas.However,our investigations conducted in the parasitological laboratory of Sun Yat-sen University(Guangzhou,Guangdong,China)show that emerging parasitic diseases still threaten many people’s health,with 340 of 880 outpatients(38.6%)receiving a diagnosis of parasitic disease,among whom 201(59.1%)had clonorchiasis and 120(35.3%)had taeniasis/cysticercosis.Furthermore,our doctors are not equipped with sufficient parasitology knowledge because this discipline is not able to maintain attraction.Many parasitic infections that result in severe consequences are treatable and preventable,but the phenomena of misdiagnosis and missed diagnosis are common and merit attention.