The presence and introduction of new potato cultivars in Kosovo has increased the yield per unit area but reduced the cultivation of native potato population. Indigenous potato is linked to specific adaptations to loc...The presence and introduction of new potato cultivars in Kosovo has increased the yield per unit area but reduced the cultivation of native potato population. Indigenous potato is linked to specific adaptations to local fanning system and specific agro ecological conditions. This research was conducted in Prishtina region which is located in the Kosovo agro ecological region （42°38′97″ latitude and 21°08′45＂ longitude at 574 m.a.s.l ）. Plant material used in this research was 18 potato accessions with different origins. The experimental design was a randomized complete block （RCB） with three replicates, while the plot sizes were 4.20 m^2. All observation and analysis were carried out on 12 plants from each accession. All characters were measured in the field and laboratory at the normal harvest time. Morphological diversity was characterized using standard descriptors. The genetic diversity studies of the investigated potato accessions showed significant genetic variation on 17 physiological and chemical parameters, which could be largely due to that they were of different origins. The genetic diversity of potato cultivars offers a wealth of natural resources from which breeders can select the most desirable genotypes based on their favorable traits.展开更多
The Penn State Worry Questionnaire(PSWQ) is a measure of worry phenomena and has been demonstrated valid in cross-cultural populations. The present study examined the factor structure and psychometric properties of th...The Penn State Worry Questionnaire(PSWQ) is a measure of worry phenomena and has been demonstrated valid in cross-cultural populations. The present study examined the factor structure and psychometric properties of the Chinese version of PSWQ(Ch-PSWQ) in a Chinese college sample(n=1243). Exploratory factor analysis of the Ch-PSWQ revealed a two-factor solution(engagement of worry and absence of worry). Confirmatory factor analysis and model comparison supported that the model of one factor with method effect provided the best fit to the data. The Ch-PSWQ and its factors evidenced good internal consistency and both convergent and discriminate validity. The present study supports the opinion that the second factor of PSWQ not only contains the component of evaluating pathological worry,but also might represent other traits.展开更多
Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual sele...Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual selection occurs when evolution in traits and preferences within populations causes differentiation among populations, such that females in alternative populations prefer sexual signals of their own population relative to others. Differentiated traits and preferences thereby play an active role in limiting gene flow between divergent populations. The effectiveness of differentiated preferences in maintaining differentiated male signals against the homogenizing effects of gene flow across populations will be limited by both the degree to which fe- males can discriminate against non-local males, and the breeding values of traits and preferences. Populations of the Hawaiian cricket Laupala cerasina have diverged in pulse rate, a sexually selected male signal, and female acoustic preference for pulse rate. Gene flow between neighboring populations may be reduced if migrants from sexually diverged populations experience re- duced mating success. We show that females discriminate among divergent songs characteristic of neighboring populations, that differences among populations in song and preference breed true in a common environment, and that mean preferences for each population closely match the mean pulse rates. Divergence in preference was observed only between populations that also dif- fered in song. Along with a striking ability to discriminate slight differences in song, correlated evolution of song and preference within populations could be a mechanism that promotes assortative mating among populations, thereby reducing gene flow, and leading to speciation in Laupala [Current Zoology 58 （3）： 416-425, 2012].展开更多
文摘The presence and introduction of new potato cultivars in Kosovo has increased the yield per unit area but reduced the cultivation of native potato population. Indigenous potato is linked to specific adaptations to local fanning system and specific agro ecological conditions. This research was conducted in Prishtina region which is located in the Kosovo agro ecological region （42°38′97″ latitude and 21°08′45＂ longitude at 574 m.a.s.l ）. Plant material used in this research was 18 potato accessions with different origins. The experimental design was a randomized complete block （RCB） with three replicates, while the plot sizes were 4.20 m^2. All observation and analysis were carried out on 12 plants from each accession. All characters were measured in the field and laboratory at the normal harvest time. Morphological diversity was characterized using standard descriptors. The genetic diversity studies of the investigated potato accessions showed significant genetic variation on 17 physiological and chemical parameters, which could be largely due to that they were of different origins. The genetic diversity of potato cultivars offers a wealth of natural resources from which breeders can select the most desirable genotypes based on their favorable traits.
基金supported by the Soft Science Office of Beijing MunicipalScience and Technology Commission of China(No.Z000608100007110)the German Academic Exchange Service(No.2006-3139)
文摘The Penn State Worry Questionnaire(PSWQ) is a measure of worry phenomena and has been demonstrated valid in cross-cultural populations. The present study examined the factor structure and psychometric properties of the Chinese version of PSWQ(Ch-PSWQ) in a Chinese college sample(n=1243). Exploratory factor analysis of the Ch-PSWQ revealed a two-factor solution(engagement of worry and absence of worry). Confirmatory factor analysis and model comparison supported that the model of one factor with method effect provided the best fit to the data. The Ch-PSWQ and its factors evidenced good internal consistency and both convergent and discriminate validity. The present study supports the opinion that the second factor of PSWQ not only contains the component of evaluating pathological worry,but also might represent other traits.
文摘Sexual selection by female choice can shape the evolution of male traits within populations, since the most attractive males experience an increase in fitness through elevated mating success. Speciation by sexual selection occurs when evolution in traits and preferences within populations causes differentiation among populations, such that females in alternative populations prefer sexual signals of their own population relative to others. Differentiated traits and preferences thereby play an active role in limiting gene flow between divergent populations. The effectiveness of differentiated preferences in maintaining differentiated male signals against the homogenizing effects of gene flow across populations will be limited by both the degree to which fe- males can discriminate against non-local males, and the breeding values of traits and preferences. Populations of the Hawaiian cricket Laupala cerasina have diverged in pulse rate, a sexually selected male signal, and female acoustic preference for pulse rate. Gene flow between neighboring populations may be reduced if migrants from sexually diverged populations experience re- duced mating success. We show that females discriminate among divergent songs characteristic of neighboring populations, that differences among populations in song and preference breed true in a common environment, and that mean preferences for each population closely match the mean pulse rates. Divergence in preference was observed only between populations that also dif- fered in song. Along with a striking ability to discriminate slight differences in song, correlated evolution of song and preference within populations could be a mechanism that promotes assortative mating among populations, thereby reducing gene flow, and leading to speciation in Laupala [Current Zoology 58 （3）： 416-425, 2012].
