9 research outputs found
Use of GGEbiplot methodology and Griffing's diallel method for genetic analysis of partial resistance to phoma black stem disease in sunflower
The objectives of the present study were to estimate the general combining ability (GCA) and specific combining ability (SCA) for partial resistance to phoma black stem and to identify the most promising combination for the selection of improved breeding lines. The response of five parental genotypes and their F1 hybrids to a phoma black stem isolate (MA6) were evaluated in a diallel programme under controlled growth chamber conditions. Significant GCA and SCA indicate that both additive and non-additive gene effects contributed in the inheritance of partial resistance to phoma black stem, however, the Baker ratio showed that the additive genetic effects were more important than nonadditive ones. It is recommended that the GGEbiplot methodology could be an excellent tool for visualizing entry by tester (diallel) data. By using this technique to analyse black stem severity data, interaction among the sunflower genotypes in providing partial resistance to phoma black stem was clearly identified. Based on GGEbiplot presentation and Griffing's diallel analysis, the mutant line âM6-54-1â showed the largest GCA, indicating contribution towards partial resistance, and the genotype B454/03 presented the smallest GCA, indicating contribution towards susceptibility. Our results show that the F1 hybrids âSDR18ĂB454/03â and âM6-54-1ĂB454/03â showing heterosis for partial resistance to phoma black stem come from the crosses between a susceptible genotype âB454/03â and two partially resistant genotypes (SDR18 and M6-54-1), originated from different breeding programmes. We conclude therefore that these genotypes possess at least some different resistance genes, which were expressed in the hybrids and led to the observed effects
Quantitative trait loci associated with isolate specific and isolate nonspecific partial resistance to Phoma macdonaldii in sunflower
Black stem, caused by Phoma macdonaldii, is one of the most important diseases of sunflower in the world. Quantitative trait loci (QTLs) implicated in partial resistance to two single pycnidiospore isolates of P. macdonaldii (MP8 and MP10) were investigated using 99 recombinant inbred lines (RILs) from the cross between sunflower parental lines PAC2 and RHA266. The experimental design was a randomized complete block with three replications. High genetic variability and transgressive segregation were observed among RILs for partial resistance to P. macdonaldii isolates. QTLâmapping was performed using a recently developed highâdensity SSR/AFLP sunflower linkage map. A total of 10 QTLs were detected for black stem resistance. The phenotypic variance explained by each QTL (R2) was moderate, ranging from 6 to 20%. Four QTLs were common between two isolates on linkage group 5 and 15 whereas the others were specific for each isolate. Regarding isolateâspecific and isolateânonspecific QTLs detected for partial resistance, it is evident that both genetic effects control partial resistance to the disease isolates. This confirms the need to consider different isolates in the black stem resistance breeding programmes. The four SSR markers HA3700, SSU25, ORS1097 and ORS523_1 encompassing the QTLs for partial resistance to black stem isolates could be good candidates for marker assisted selection
QTL mapping of partial resistance to Phoma basal stem and root necrosis in sunflower (Helianthus annuus L.)
Phoma macdonaldii infects different tissues of sunflower and causes reduction in yield and oil content. The aim of present research was to identify genomic regions involved in partial resistance of sunflower to four Phoma macdonaldii basal stem and root necrosis isolates using our improved map constructed with 191 SSR and 304 AFLP markers. The experiment was conducted using F9 recombinant inbred lines (RILs) from a cross between âPAC2â and âRHA266â. Results showed that âPAC2â was more resistant than âRHA266â to basal stem necrosis isolate âTA6â and root necrosis isolate âTA4â. By contrast âRHA266â was more resistant than âPAC2â to basal stem necrosis isolate âTA9â and root necrosis isolate âTA2â. Transgressive segregation was observed for partial resistance to all four isolates. Some recombinant lines presented partial resistance or susceptibility to all isolates. Twenty-seven QTL with phenotypic variance ranging from 7 to 29% were detected. Among them 13 were âisolate-specificâ and others were common for partial resistance to different isolates (isolate-non-specific). Most of the QTLs in common have major effects for resistance to each isolate. The âisolate-non-specificâ QTLs were located on linkage groups (LG) 5, 6, 8, 12, 13 and 15. The markers âHA3555â on LG12 and âE33M48_26â on LG6 as well as âE33M48_20â on LG13, which are each linked to QTLs of different basal stem and root necrosis isolates, could be used in marker-assisted selection to introduce tolerance to four Phoma macdonaldii isolates into elite sunflower breeding lines
Social Phobia in Persian Adults with Stuttering
Background: Stuttering is a communication disorder. It is expected that
stuttering may have negative impact on individualsâ mental and emotional
health, which may affect their quality of life. Therefore, this paper aims to study
components of social phobia inventory in Persian adults with stuttering and
compare the likelihood (odds) of social phobia in the stuttering group to that in
the control group.
Methods: Using social phobia inventory, this case-control study compared
social phobia in 33 adults with stuttering and 33 age-gender-education matched
subjects with fluent speech. All the participants were 18 years or above.
Results: Independent t-test showed that the total score of the social phobia
inventory. Its fear component has significant statistical differences between
group of adults with and without stuttering. Moreover, the adults with stuttering
have over two times more social phobia symptoms than that in ones who donât.
Conclusion: Our results suggest that social phobia should be considered in
therapy programs for adults with stuttering. In addition to restructuring speech,
a part of the treatment program should address peopleâs social phobia, especially
their feeling of fear, in order to curtail some of the negative consequences
associated with stuttering
QTL analysis of yield-related traits in sunflower under different water treatments
A set of sunflower recombinant inbred lines (RILs) was used to study agronomical traits under greenhouse and field conditions each with two water treatments and three replications. The difference among RILs was significant for all the traits studied in all conditions; and water treatmentâĂâRILs interaction was also observed for most of the traits in both field and greenhouse conditions. Because of the low rate of drought stress, this part of field data are not informative. Several quantitative trait loci (QTLs) were identified for yieldârelated traits with the percentage of phenotypic variance explained by QTLs (R 2) ranging from 4% to 40%. Several QTLs for grain yield per plant (GYP) under four water treatments were identified on different linkage groups, among which two were specific to a single treatment (GYPN.4.1 , GYPI.7.1 ). Three QTLs for GYP were overlapped with several QTLs for droughtâadaptative traits detected in our previous study (Poormohammad Kiani et al. 2007b). The whole results do highlight interesting genomic regions for markerâbased breeding programmes for drought tolerance in sunflower
Analyse génétique des réponses physiologiques du tournesol (Helianthus annuus L.) soumis à la sécheresse
Recombinant inbred lines (RILs) coming from the cross "PAC2.RHA266" were used to develop an integrated and high density genetic-linkage map using SSR and AFLP markers. QTLs involved in the genetic control of water status traits (RWC, Yw, Ys, Yt and YsFT) and osmotic adjustment (OA) under well-watered and water-stressed conditions were identified. Among 24 QTLs detected under wellwatered conditions, 5 (about 21%) were also detected in the water-stressed treatment (stable QTLs) and the rests were specific. A major QTL for OA on linkage group 5 is overlapped with the QTLs for several water status traits. In order to understand the response of yield and related agronomic traits to different water treatments and growth conditions, RILs and their parents were phenotyped at greenhouse and fieldcondition with two water treatments. Using our saturated linkage map, the QTLs controlling agronomical traits were identified and their co-location with QTLs for plant water status and osmotic adjustment were investigated. Genotypic variation for water status and gas exchange parameters under different water treatments were studied and the differential expression of four water-stress associated genes were investigated. The expression level of aquaporin genes in leaves of four RILs and their parents was down regulated by water stress and was associated with relative water content (RWC). Down-regulation was also associated with genomic regions having alleles with negative effects on plant water status. Net photosynthesis rate (Pn) and the fructose-1,6 bisphosphatase gene expression levels were associated mainly after rehydration. The genomic regions involved in genetic variability for chlorophyll fluorescence parameters were mapped in RILs and the differential expression of various antioxidant genes were investigated by quantitative real-time RT-PCR in four selected RILs and their parental lines. Significant higher level of POD (66-fold) was observed. The putatively drought-tolerant genotype (C100) showed the highest transcript level for SOD, CAT, PSI P700 and PSII 32 Kda Protein resulting in the maintenance of photosynthesis under water stress. QTL mapping and graphical genotyping showed that the positive or negative alleles of some QTLs such as "NPQD.11.1" and "1-qPD.2.1" could be associated with the transcript abundance of SOD and CAT in the putatively drought-tolerant genotype (C100). Molecular markers associated with osmotic adjustment-related traits as well as with different agronomical traits were identified in well-watered and water-stressed plants for a population of M6 mutant linesAfin de progresser dans la comprĂ©hension des caractĂšres clĂ©s impliquĂ©s dans les processus de tolĂ©rance Ă la sĂ©cheresse chez le tournesol, nous avons rĂ©alisĂ© plusieurs expĂ©rimentations, en conditions contrĂŽlĂ©es et au champ sur des populations de tournesol exprimant diverses sources de variabilitĂ© gĂ©nĂ©tique : des lignĂ©es recombinantes (RILs) et des mutants. La variabilitĂ© gĂ©nĂ©tique pour la tolĂ©rance Ă la sĂ©cheresse, Ă travers l'Ă©tude des relations hydriques et de caractĂšres agronomiques, a Ă©tĂ© Ă©tudiĂ©e. Dans un premier temps, nous avons construit une carte gĂ©nĂ©tique intĂ©grĂ©e et Ă haute densitĂ© en utilisant une population de LIRs issue du croisement entre deux gĂ©notypes PAC2.RHA266. Les QTLs contrĂŽlant les caractĂšres associĂ©s Ă l'Ă©tat hydrique des plantes (teneur en eau relative, potentiel hydrique et ses composantes) et Ă l'ajustement osmotique (AO) dans des conditions irriguĂ©es' et de contraintes hydriques' ont Ă©tĂ© identifiĂ©s. Parmi 24 QTLs dĂ©tectĂ©s dans des conditions irriguĂ©es, cinq (environ 21%), ont Ă©tĂ© Ă©galement dĂ©tectĂ©s dans la condition contrainte hydrique. Ces QTLs sont considĂ©rĂ©s comme stables comparativement Ă ceux spĂ©cifiques aux diffĂ©rentes conditions hydriques. Un QTL majeur pour l'AO sur le groupe de liaison 5 est co-localisĂ© avec les QTLs contrĂŽlant plusieurs caractĂšres de l'Ă©tat hydrique des plantes. Ce QTL pourrait ĂȘtre utilisĂ© pour la sĂ©lection assistĂ©e par marqueurs. Les LIRs et leurs parents ont Ă©tĂ© phenotypĂ©s en serre et au champ avec deux traitements hydriques (irriguĂ© et sĂ©cheresse). Le phĂ©notypage a portĂ© sur des caractĂšres agronomiques (phĂ©nologie, surface foliaire Ă la floraison, hauteur des plantes, sĂ©nescence, rendement et ). En utilisant notre carte gĂ©nĂ©tique, les QTLs liĂ©s Ă ces caractĂšres ont Ă©tĂ© identifiĂ©s et leurs colocalisations avec les QTLs contrĂŽlant l'Ă©tat hydrique des plantes et l'ajustement osmotique ont Ă©tĂ© analysĂ©es. Nous pouvons noter que certains QTLs associĂ©s Ă la tolĂ©rance au dĂ©ficit hydrique sont situĂ©s dans les mĂȘmes positions que ceux associĂ©s au rendement. Par exemple, le QTL majeur identifiĂ© pour l'AO est Ă©galement dĂ©tectĂ© pour le rendement par plante, la surface foliaire et le poids du capitule. Ceci indique une base gĂ©nĂ©tique commune pour la tolĂ©rance Ă la sĂ©cheresse et les caractĂšres associĂ©s au rendement. Dans un deuxiĂšme temps, nous nous sommes intĂ©ressĂ©s Ă l'expression de gĂšnes impliquĂ©s, d'une part dans la tolĂ©rance Ă la contrainte hydrique, et d'autre part dans les processus limitant les dommages oxydatifs, pour quatre gĂ©notypes ayant un comportement contrastĂ© en situation de contrainte hydrique. L'expression des gĂšnes Ă©tudiĂ©s a Ă©tĂ© mise en relation avec les caractĂšres physiologiques mesurĂ©s concernant l'Ă©tat hydrique, la photosynthĂšse et la photochimie Ă©tant impliquĂ©es dans les processus d'assimilation du carbone pour la croissance. Parmi les principaux rĂ©sultats, on note une diffĂ©rence notable de l'expression des gĂšnes impliquĂ©s dans l'Ă©tat hydrique des diffĂ©rents gĂ©notypes, plus particuliĂšrement de l'aquaporine. L'expression du gĂšne de l'aquaporine est corrĂ©lĂ©e au caractĂšre hydrique RWC. Pour les processus photochimiques, ce sont principalement les niveaux d'expression des gĂšnes codant pour la superoxide dismutase, la catalase et la peroxidase qui diffĂ©rencient les gĂ©notypes soumis Ă la sĂ©cheresse. Les marqueurs molĂ©culaires associĂ©s Ă l'ajustement osmotiques et Ă diffĂ©rents caractĂšres agronomiques ont Ă©tĂ© identifiĂ©s chez une population de mutants M6TOULOUSE-ENSAT-Documentation (315552324) / SudocSudocFranceF
Proactive and reactive inhibitory control are differently affected by video game addiction: An eventârelated potential study
Abstract Introduction Video game addiction (VGA) is associated with physical and mental disorders, one of which is problem in executive function, particularly inhibitory control. The present study aimed to investigate reactive and proactive inhibitory controls by eventârelated potential (ERP). Methods Thirty video game (action video games)âaddicted subjects and 30 matched healthy controls participated in the study, who were tested by the selective stopâsignal task. Results The main results revealed that the VGA group had significantly more problems in preparatory processes and proactive stop trials, showing that VGA has a negative effect on proactive inhibition. Conclusion Finding the problem in proactive inhibitory control might be helpful in developing new treatments and rehabilitation methods in these fields
EEGâbiomarker theta/beta ratio and attentional quotients in adults who stutter: An electrophysiological and behavioral study
Abstract Introduction There is increasing evidence that connects developmental stuttering to attention. However, findings have represented contradiction. Therefore, this study was conducted to investigate the possible relationship between stuttering and attention in resting and undertask conditions. Methods In a crossâsectional study, 26 rightâhanded AWS (adults who stutter) and 25 matched fluent speakers were enrolled. Demographic data were collected, and the Beck anxiety inventory (BAI) was filled out for all participants. Then, QEEG was conducted, followed by IVA2. CPT test for all subjects. Finally, data were analyzed using SPSS software version 16. Results AWS indicated significantly weaker auditory focus attention in the task (p = .02) than the control group, while a similar restingâstate EEG marker of attention was found between groups (p > .05). Moreover, attention was not correlated between the two conditions (p > .05). Conclusion The EEG marker of attention did not necessarily designate the attentional performance of AWS under the task. Furthermore, attentional skills could be considered in the assessment and therapeutic programs of at least some groups of AWS