Contribution to the genome size knowledge of New World species from the Heliantheae alliance (Asteraceae)

This article contributes first genome size assessments by flow cytometry for 16 species, 12 genera, and 3 tribes from family Asteraceae, mostly belonging to the Heliantheae alliance, an assembly of 13 tribes from subfamily Asteroideae with a large majority of its species in the New World. Most genome sizes are accompanied by their own chromosome counts, confirming in most cases, although not all, previous counts for the species, and revealing possible cases of unknown dysploidy or polyploidy for certain taxa. The data contribute to the pool of knowledge on genome size and chromosome numbers in the family Asteraceae and will further allow deeper studies and a better understanding on the role of dysploidy in the evolution of the Heliantheae alliance. However, we still lack data for tribes Chaenactideae, Neurolaeneae, Polymnieae, and Feddeeae (the latter, monospecific) to complete the alliance representation.     

Revised structures for the bejarols from Santolina oblongifolia

The ¹³C NMR spectra of the bejarols isolated from Santolina oblongifolia suggest they are nerolidol derivatives with a 2,6-dialkyldihydropyranose structure.     

Two New Alkamides from Spilanthes callimorpha

Two new alkamides, 8,11-dihydroxy-dodeca-2E,4E,9E-triensaureisobutylamid （Compound 1） and 7-hydroxy-trideca-2E,8E- dien-10,12-diynoic acid isobutylamide （Compound 2）, as well as eight known compounds were isolated from the whole plants of Spilanthes callimorpha. The structures of the alkamides were characterized on the basis of their spectral data.     

毛冠菊属的花粉形态和结构及其系统学意义

对国产菊科特有属的花粉形态和结构进行了光学显微镜、扫描电镜和透射电镜的观察和研究。该属的花粉可以分为圆球形、扁球形和长球形三种类型。种之间的花粉差异主要表现在大小、形状和外壁纺饰的细微变化等方面。与紫菀族、竿里光旋和旋覆共族三个族的代表种的花粉特征进行对比分析,并结合其它生物演化证据,可得取以下结论：（１）支持ａｎｄ－Ｍａｚｚｅｔｔｉ的分类意见,毽炙属应归于紫族中;（２）毛冠菊属的花粉可划分为圆球     

后河自然保护区菊科植物区系及药用资源分析

湖北后河国家级自然保护区菊科植物种类共５５属１２４种（含变种）,其中温带区系成分共３７属８８种,热带区系成分共１１属１８种,世界分布成分６属１７种,中国特有分布成分１属１种,植物区系以温带区系成分占优势。后河菊科药用植物资源十分丰富,有５３个属１２１种有药用价值,具有很大的开发利用前景。     

Rhamnocitrin-3-glucuronid in Verbesina myricephala

The structure of a new flavonol-glycoside isolated from the herb of Verbesina myricephala Sch. Bip. has been established as the 3-O-β-d-glucopyranuronide of 3,5,4′-trihydroxy-7-methoxy-flavone (rhamnocitrin-3- glucuronide.     

Anti-inflammatory activity of a new triterpenoid saponin from carthamus tinctorius linn

A new bioactive triterpenoid saponin 3β-O-[β-D-xylopyranosyl(1 → 3)-O-β-D-galactopyranosyl]-lup-12-ene-28 oic acid-28-O-α-L-rhamnopyranosyl ester compound (A), was isolated from the methanolic fraction of the roots of this plant by various colour reactions, chemical degradations and spectral analysis. Compound (A) showed anti-inflammatory activity.     

加拿大一枝黄花根系和根际土壤水浸液对萝卜和白菜种子萌发及幼苗生长的影响

用加拿大一枝黄花根系及根际土壤水浸液对白菜和萝卜的化感作用进行了研究。结果表明,加拿大一枝黄花根系水浸液和根际土壤水浸液对白菜和萝卜种子的萌发具有抑制作用。根际土壤水浸液对白策和萝卜幼苗生长具有促进作用,而对其胚根的伸长生长则具有显著的抑制作用。0．05g／mL根系水浸液处理显著抑制萝卜幼根的伸长,但其它浓度对白菜和萝卜幼苗生长和根系伸长的影响不明显。实验还表明高浓度的根系水浸液和根际土壤水浸液明显抑制白菜和萝卜的根系脱氢酶活性和硝酸还原酶活性。     

Elemanolides from Verbesina seattonii

Two novel sesquiterpene lactones were isolated from Verbesina seattonii. Their structures were elucidated as elemanolides possessing an intramolecular hemiacetal function on the basis of an extensive spectral analysis and crystal structure determination.     

Possible significance of changes in the light requirement of Cirsium palustre seeds after dispersal in ash coppice

Abstract. It is demonstrated that after the feelling of ash coppice Cirsium palustre becomes established from seed that was produced during the previous coppice cycle and has lain underground for several years. These seeds are light-requiring and it is probable that their germination is triggered by exposure to light during coppicing in winter.
It is assumed that the seeds become light-requiring because phytochrome in the far-red absorbing form high. This facilitates their incorporation in the seed bank in summer. However, the disappearance of Pfr is inhibited at low temperatures; this means that the seeds can store the light stimulus in winter and will not germinate until they experience higher temperatures in spring. The significance of the inhibition of seed germination under a leaf canopy is that it enhances the seeds chance of being incorporated in the soil seed bank.