摘要:

Populations ofPolygonurn viviparurnwere investigated in the Swiss Alps at 14 sites, ranging from 450 m to 2530 m above sea level. The average length of stems and the mean number of reproductive organs (flowers + bulbils) decreased significantly with increasing altitude. On average, the ratio of flowers to bulbils per inflorescence also declined so that at high altitudes, bulbil production was more pronounced. Increased allocation to vegetative reproduction is discussed as an adaptation to cold climate. It is suggested that enhanced vegetative reproduction might be controlled by incornplete floral induction in high altitudes. In addition variability within and between populations was investigated by isozyme electrophoresis and the examination of bulbil colours. A considerable amount of variability was found in alpine populations. The demonstrated genetic variability showed that inP. viviparumit is likely that minor sexual reproduction is maintained even under alpine conditions. This is reflected in different enzyme phenotypes and different bulbil colours.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00085.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The small annual generaCrithopsis, Heteranthelium, HenrardiaandAmblyopyrumare revised, maps showing the distribution of the species are presented and the known chromosome numbers are confirmed. The phylogenetic relationships of each genus are discussed. Results of intergeneric hybridizations including the four genera are reported.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00086.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00087.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The effect of pollination on floral scent composition and production in the moth‐pollinated orchidPlatanthera bifoliawas studied. A significant decrease in scent production was detected both two and five days after pollination. The proportion of wilted flowers was higher in pollinated compared to control plants after seven days. A principal component analysis (PCA) showed how pollination reduced scent production. All scent compounds were affected by pollination, even though some compounds had larger impact on the overall scent reduction. A classification of samples offered a quantitative test of the changes found in individual plants after pollination. The induced decrease in floral scent production following pollination is suggested to be of adaptive value for both plants and pollinator

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00088.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00089.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Four new species ofChlorophyrumfrom tropical Africa are described: C.graniticolafrom Zimbabwe, C.minorandC. perfoliatumfrom Zambia, and C.velutirzumfrom Malawi, Tanzania, Zambia and Zaire.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00090.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00091.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

New information relating to structure andor wider distributional records are given for four species of Cyperaceae indigenous to Zambia and/or Zimbabwe. Three are members of tribe Cypereae (Sphaerocyperus erinaceus, Cyperus albopilosus, C. ciltochty‐socephalus);one of Ficineae (Isolepis trollii). Tribal delimitation follows that of Goetghebeur (1986

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00092.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Ruellia nocturna, a large‐ and night‐flowering shrub from Central Somalia is described and illustrated, and its relationship to other large‐flowered species occurring in the area is disc

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00093.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1993.tb00094.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY