云南含笑花粉萌发研究

应用离体培养和人工授粉的方法对云南含笑花粉的萌发进行了研究。栽培和野生云南含笑花粉的萌发率有很大的差异,分别为20％和90％。首次报道了云南含笑的花粉粒在离体培养基上萌发2条花粉管的现象。云南含笑花粉在灰岩含笑花柱头上的萌发率和萌发时间与离体培养基上的相同,表明灰岩含笑的柱头对云南含笑的花粉没有排异现象。     

云南西双版纳植物区系新资料

<正> 多年生草本,茎细长而匍匐,节上生根。叶片膜质,近圆形或肾形,长0.5—1.5厘米,宽0.7—2.5厘米,基部心形,5—7裂,裂片阔倒卵形,边缘有钝齿,掌状脉6—8,上面疏生明显的刺状毛,下面光滑;叶柄长0.7—3厘米,无毛;托叶小,薄膜质,近肾形,具不规则的浅裂。聚伞状伞形花序通常顶生,与叶对生,有花序2—3,花序梗纤细,两侧的花序梗长达1厘米,中间的花序梗仅长1—2毫米,小总苞披针形,长约1毫米,膜质,小伞形花宇有花2—5,花无柄,花瓣卵形,长约0.5     

Evidence for energy-dependent copper efflux as a mechanism of Cu2+ resistance in the cyanobacterium Nostoc calcicola

Wild-type Nostoc calcicola carried out oxygenic photosynthesis extremely sensitive to copper. A Cu(2+)-resistant mutant (Cu-R1) of the cyanobacterium grew normally at high concentrations of Cu2+. Its ability to grow under such conditions was found to be due to mutational acquisition of an energy-dependent efficient system of Cu(2+)-efflux, which rendered Cu(2+)-inhibited oxygenic photosynthesis fully reversible.     

Bryophytes new to Albania from the British Bryological Society field meeting in 2014

Seventy bryophytes are reported new to (or confirmed for) Albania from a meeting of the British Bryological Society in 2014, based in the Valbona Valley. The high number of new records reflects the poor state of our knowledge of the bryoflora of the country. Many of the newly recorded species have Alpine, Boreal or even Arctic affinities. However the most significant record is that of Jungermannia calcicola Konst. & Vilnet., previously known only from the Russian Caucasus.     

紫花含笑（♀）、灰岩含笑（♂）及其杂种F1代花粉萌发试验研究

对紫花含笑(Michelia crassipes)、灰岩含笑(M.calcicola)及其杂种F1代花粉生活力进行了研究,为基于紫花含笑和灰岩含笑杂种F1代的含笑属观赏植物新品种培育与种质创新提供科学数据及研究资料.研究发现,亲本(紫花含笑和灰岩含笑)新鲜花粉萌发率均可达90％以上,杂种F1代花粉萌发率从38％到79％不等,平均为57.7％,低于双亲.亲本及其杂种F1代花粉萌发的最适温度为25℃,温度过高花粉管的伸长受到抑制,并导致花粉管顶端破裂.亲本及多数杂种F1代的新鲜花粉在100 g/L和150 g/L的蔗糖浓度下萌发率都较高;经-20℃贮藏后的花粉对蔗糖浓度的敏感性要高于新鲜花粉.杂种F1代及其亲本的花粉在离体培养中均会出现双萌发管现象.番红染料对液体培养基中的花粉有致死和染色作用,有利于统计杂种F1代及其亲本的花粉萌发率.     

Variation in elemental content among and within trichomes in Nostoc calcicola 79WA01 measured by x-ray micro-analysis

Abstract: Using X-ray micro-analysis elemental content and dry weight were measured in single vegetative cells along eight trichomes from a culture of Nostoc calcicola . Nearly all of the variation in the pooled population could be attributed to the variation among trichomes, with coefficients of variation (CV) between 0.2 and 0.7. Within trichomes the CV was 0.10–0.13. Chlorine, sodium, calcium and potassium were the elements that contributed most to the dispersion of the trichomes as shown by canonical variate analysis. These results suggest that there exists an ionic or molecular exchange between cells along the trichome and that the trichome may be regarded as a counterpart to an individual cell in a binary dividing population.