摘要:

Scanning electron microscopy was used to examine stem, leaf, staminal and stylar hairs on species belonging toSolanumL. sectionSolanum. The surface morphology of these hairs is illustrated. Simple, uniseriate hairs characterize the sectionSolanum, and these may have eglandular or glandular heads; they are usually multicellular, but in some species the stylar hairs appear to be unicellular. In addition, stalked glands, described here as spherical, four‐celled glands, are universally present in species belonging to the sectionSolanu

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1982.tb02583.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Leaf surfaces of the nativeHeracleum sphondylium, the alienHeracleum mantegazzianumand the interspecific hybrid were examined using SEM and light microscopy. The surfaces differed in hairiness, especially in the length of the hairs, although the hairs did not differ in general form, or distribution on the leaf surface. Stomata differed little in length, width or frequency, but there were differences in the sort of stomata in relation to the surrounding epidermal cells. The hybrid material was intermediate between the parental species, and sometimes displayed aberrant trichomes that were contorted in contiguous pairs.The results are discussed in relation to other work on the epidermal features of the Umbelliferae: as a means of discriminating the three taxa, and in relation to the ecological distributions of the species.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1982.tb02584.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

British Umbelliferae form a natural cohesive taxon, having patterns of habitat distribution, reproductive biology and life‐history that distinguish them from other British dicotyledons. They are usually found in open sites, and are local or rare in distribution.Almost half of British species have the andromonoecious sex habit. Perfect flowers are usually protandrous. The floral composition of umbels, and the pattern of opening of the inflorescence combine to produce a protogynous effect. These have been interpreted as mechanisms which decrease competition for resources between male and female functions in the plant, such that separate maternal and paternal fitness can become optimal.Seeds often require a chilling treatment, alternating temperatures, or a period of after‐ripening before they are capable of germination. Schizocarps are of low weight. This seems to relate to the relative openness of habitat wherein unbellifers are found. Patterns of dry matter distribution reflect the life‐history strategies of various umbellifer species. Agromyzid leaf miners parasitize the more widespread species, and those which are found in a greater number of different hab

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1982.tb02585.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

All previously reported chromosome counts for Umbelliferae of tropical and southern Africa are summarized, two from Socotra are included. New counts on 35 taxa in 14 genera are provided, mostly from Malawi or South Africa.Alepidea, Baumiella, Diplolophium, Lefebvrea, andLichtensteiniaare included for the first time.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1982.tb02586.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Lens montbretiihas a diploid chromosome number of 2n = 12 whereas the remainder of the genus has 2n = 14. In addition there are marked karyotype differences. These, combined with morphological characteristics which distinguish it from other species ofLens, are considered to be an adequate basis for the returning of the taxon to the genusViciaasV. montbretiiFisch.&Mey.

ISSN:0024-4074    

DOI:10.1111/j.1095-8339.1982.tb02587.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY