河北中国种子植物特有属初步研究

河北植物区系自然分布中国种子植物特有属18属,含17种2变种,归13科.对河北种子植物特有属分析表明:河北种子植物特有属以残存的古特有属为主,温带性质显著,热带渊源明显;草本属(尤其多年生草本属)占显著优势,占总属数的61.1％,而木本属仅占27.8％.单种属和双种属占明显优势,占总属数的84,2％.中国特有属种无毛独根草(Orestitrophe rupifraga Bunge var.glabrescens W.T.Wang)、缘毛太行花(Taihangia rupestris Yu et Li vat.ciliata Yu et Li)(河北无原变种)和长裂太行菊(Opisthopappus longilobumShih)仅在河北分布.

Genetic Relationships Among Soluble Carbohydrates, Anthocyanins and Growth Characteristics in Leymus (Gramineae) Detected with Molecular Markers

Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization requirement, growth, and soluble carbohydrate accumulations of the winter-annual Triticeae species. Two hundred and four unmapped AFLP markers and genome-specific DNA markers genetically linked to the vrn-1 gene were used to detect QTL controlling soluble carbohydrate accumulations, anthocyanin coloration and growth characteristics in a segregating population derived from open pollinated Leymus cinereus x L. triticoides hybrids. These perennial Triticeae grasses are distinguished by adaptation and growth habit. As expected, positive trait correlations and pleiotropic gene effects were detected for soluble carbohydrate accumulations and anthocyanin coloration. Likewise, positive trait correlations and pleiotropic gene effects were detected for tillering, leaf development, leaf growth, regrowth and rhizome spread. However, soluble carbohydrate accumulations were not associated with attenuated growth. In fact, several DNA marker alleles, including one near vrn-Ns1, had positive effects on soluble leaf carbohydrate concentrations and low temperature growth. The corresponding DNA marker near vrn-Ns1 had more specific effects on tillering. We speculate that vrn-1 exerts quantitative effects on low-temperature soluble leaf carbohydrate accumulations and growth habit of the perennial Leymus. However, a number of other DNA markers displayed highly significant effects on soluble carbohydrate accumulations and various growth characteristics. Findings indicate that anthocyanin coloration may be a useful phenotypic marker for soluble carbohydrate accumulation. Although variation for soluble carbohydrates was not associated with attenuated growth in this population, this trait was under genetic control.

Comparing Ecological Functions of Eastern and Southern Slopes of a Rangeland Ecosystem in Chaharbagh Region, Golestan Province, Iran

Getting aware of one kind of soil surface attributs is very important. Assessment of important attributes of soil and vegetation can help us to be aware of rangeland potential and help us to determine its situation. The goal of this research is to determine some plant and soil indicators of hilly winter rangelands of Eastern and Southern slopes of Chaharbagh region in Golestan province. By considering plant cover and soil surface attributes, it used the SSCC （soil surface classification） method to assess soil surface attributes. The length and width of ecological patches were measured in the forms of lichen, lichen-Grass, forbs, shrub and bare soil inter patches with litter. Also in this research, it measured the 11 soil surface parameters. These parameters are belonging to three main soil attributes stability, infiltration and nutrient cycles. These three indicators were measured in east and west of Eastern and Southern slopes of this ecosystem and showed significance differences （p 〈 0.05） in shrub, forbs and lichen-grass. In southern and especially in west aspect, these indicators in shrub were more than Eastern. But, in lossy hill of Eastern, lichen-grass patch is more significant. The most important ecological indicators of east landscapes of this region are forbs and lichen-grass.

烟草的家族

烟草是当今世界五大作物(稻、麦、棉、豆、烟)之一,外貌与内涵都有其特殊之处,尤其是最具使用价值的红花烟,株高叶大,婷婷玉立,花红叶绿,令人赏心悦目。十五世纪末。