摘要:

An investigation of cytological, palynological, and taxometric variation inLimonium binervosum(G. E. Sm.) C. E. Salmon has revealed an extensive pattern of hierarchical relationships within this agamospermous group in the British Isles. The group is either triploid (2n = 27) or aneuploid tetraploid (usually 2n = 35) with a highly jumbled karyotype. Pollen is either not produced or of very low stainability (in the range 0–38%). Well stained pollen grains are usually abnormally large resulting from a failure of a meiotic division. These facts as well as the presence of only a single self‐incompatible polledstigma morph in the majority of the group suggest that it is obligately agamospermic. The very strong correlation of taxometric relationship and geographical distance between variants suggests that evolution in the group has occurred by the gradual accumulation of mutations giving rise to morphologically and geographically related seed clones. The hierarchical pattern of variation as revealed by cluster analysis has been used as the basis of a hierarchical classification of the gr

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02081.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Material consisting of 157 accessions of 69 FinnishTaraxacumagamospecies, representing 7 sections, was grown in an experimental field for comparison of certain botanical and nutritional characteristics. This paper gives the collecting data as well as cytological and reproductive characteristics of the material. The largest sectionTaraxacum (Vulgariu) was represented by 60 agamospecies, 59 of them triploid (2n = 24) and one tetraploid (T.penicilliforme, 2n = 32). The tetraploid and 37 triploids were chromosome counted for the first time. The diploid sexual speciesT. obtusilobumfrom Sweden was included for comparison. Other sections consisted of 3 triploids and 6 tetraploids, 3 tetraploid species of the sectionErythrospermabeing chromosome counted for the first time. Seedlings with deviating numbers were occasionally found. A banding technique of the chromosomes was developed but it did not allow the exact identification of other than the satellite chromosomes. Species‐specific features were found in the flowering phenology and in several pollen characteristics (stainability, mean and variability of the size). There were indications of genetic variation within certain agamospecies in pollen characteristics. Isolated and emasculated (mostly only isolated) flower heads gave mostly a full seed set, which indicates obligate, autonomous agamospermy. Lower seed sets ofT. adami, T. dahlstedtiiandT. hamatiformein isolation may be a sign of facultative apomixis in these species, requiring further stud

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02082.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

A new section ofPlantagobelonging to subgen.Plantagois proposed. It includes two species,P. rigidaH.B.K. andP. tubulosaDecne., both small plants from moist habitats in the highest parts of the Central and Northern Andes, the last also from a single place in Mexico and Guatemala. Geographic variation within both species is studied. This is the final paper in a series of revisions ofPlantagoin South and Central America.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02083.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Pavonia melhanioides Thulin is described from the Sidamo Region in S Ethiopia.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02084.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The present paper contains further additions and corrections to earlier papers on the orchid flora of Thailand. Five new species are proposed, three species are new records for Thailand, and three earlier established taxa are reduced to synonyms.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02085.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The genusIphionaCass. emend. A. Anderb. (Compositae‐Inuleae‐Inulinae) is revised and considerably amended. The former generaGrantiaBoiss. (=Perralde‐riopsisRauschert) andHirschiaBaker are included as well as the major part ofIphionaCass. s.str. and the speciesInula grantioidesBoiss., andPulicaria phillipsiaeS. Moore. Five new combinations are made: I.anthemidifolia(Baker) A. Anderb., I.arachnoidea(Boiss.) A. Anderb.,I. grantioides(Boiss.) A. Anderb.,I. phillipsiae(S. Moore) A. Anderb., andI. senecionoides(Baker) A. Anderb. The new speciesI. teretifoliaA. Anderb. is described. A discussion of the phylogeny of the group and a cladogram, involving reticulation, of theIphionaspecies are presented. The 11 species are distributed in Egypt, Israel, Jordan, Sudan, Ethiopia, Somalia, Saudi Arabia, Peoples Democratic Republic Yemen, Oman, Iran and Pak

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02086.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

An amended description ofGymnostachyum knoxiifoliumC. B. Clarke is given. Reasons for its transfer toCosmianthemumBrem. are discussed and the new combination published.Pseuderanthemum parviflorumRidl.,Ptyssiglottis parviflora(Ridl.) Ridl., andSphinctacanthus malayanusRidl. are sunk into its synonymy.

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02087.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Two collections ofCyathus costatusfrom Venezuela form a corroborating basis for a validating decription of Lloyd's species which has not heretofore been published legitimately. Lloyd's specific epithet is retained. Comparison with Lloyd's “type” material is made and illustrations of the latter are provided, as well as a new and emended description embracing the original and the recently‐recognized spec

ISSN:0107-055X    

DOI:10.1111/j.1756-1051.1985.tb02088.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY