Salsoloideae

Abstract: A first comprehensive phylogenetic analysis of tribe Salsoleae s.l. (Salsoloideae: Chenopodiaceae) is presented based on maximum parsimony and maximum likelihood analysis of nuclear ribosomal internal transcribed spacer and chloroplast psbB‐psbH DNA sequences. Our data strongly support (1) the sister relationship of Camphorosmeae to the Salsoleae s.l.; (2) splitting of Salsoleae s.l. into two monophyletic tribes, Salsoleae s.s. and Caroxyloneae tribus nova; (3) the current status of most monotypic or oligotypic genera in Salsoleae; and (4) polyphyly of the Botschantzev and Freitag (among others) circumscriptions of Salsola, which falls into 10 (on average) monophyletic genera/lineages. Three well‐supported genera are described as new (Pyankovia, Kaviria, and Turania), and four previously described genera are resurrected (Caroxylon, Climacoptera, Kali, and Xylosalsola). Salsola s.s. include a group of central and southwest Asian and north African species that consists of Salsola sect. Salsola s.s., Salsola...

Abstract: Photosynthetic pathways are reported for 305 species ofChenopodiaceae from Africa, Asia and Europe. Ecological characteristics, phytogeography and life forms of all species are given, and their correlation with relevant CO2-fixation types are discussed. 205 species (67.2%) exhibit the C4-pathway and 100 species (32.8%) the C3-pathway of CO2-fixation. Most of the C4 species are of Irano-Turanian origin. The diversity of C4 species of the Irano-Turanian phytochoria, with very harsh winters, are interpreted by the active period of Chenopods in summer. There is a close relationship between some special morphotypes and respective photosynthetic type. Halophytes and xerophytes with articulated stems and stem succulents ofAnabasis-type are exclusively C4. Leaf succulent halophytes and xerohalophytes are predominantly C4. Hygrohalophytes with leaf or stem succulence are often C3. Probably many C4Salsoleae have been evolved in the Afroasiatic arid zone after the climatic changes of the Miocene. Among them there is a high proportion of annuals that have a younger origin. There is some evidence that the present Chenopods of the subfamily “Salsoloideae” may have their ancient stock in NW Africa. We found close taxonomic relationships between photosynthetic pathways and infrageneric classification in genera with both types of C3 and C4, likeAtriplex andSuaeda.

Abstract: Somewhat understandably, interest in pollination biology of members of the Chenopodiaceae has been scant (see Percival, 1965, who made no mention of the family), or else has focused on the "allergic reaction" caused by some members of the family (see Homan, 1963, discussion of Chenopodium album as a secondary factor during the ragweed season). Mode of pollination in chenopods is, we believe, open to question in many instances. The general supposition has apparently been that the family is more or less uniformly anemophilous (e.g., Wodehouse, 1935, 1945, 1971), this in association with an abundant, weedy habit. In accordance, Proctor and Yeo (1972) alluded to the significant presence of chenopodiaceous pollen in the "pollen rain." Perhaps the general impression is that chenopods are simply "uninteresting" in terms of pollination biology. However, if some literature is retraced, a rather different perspective may be gained. Volkens (1893) offered the proposition that most members of the family may actually be entomophilous. Knuth (1909) presented what remains as probably the most detailed account of pollination in the Chenopodiaceae, not to mention a number of other families. From his work one is left with the understanding that chenopods are generally either anemophilous or self-pollinated; however, Knuth did not exclude the possibility of insect visits to such taxa as Salsola kali L. More recently, Ponomarev and Lykova (1960) credited M. Iljin with the suggestion that entomophily is characteristic of the subfamily Spirolobeae (=Salsoloideae, cf. Blackwell, 1977), admitting, however, that the situation had not been adequately studied. Ponomarev and Lykova further credited Z. P. Bochantseva and T. Vitovich with establishing self-pollination in several taxa of chenopods, including certain species of Salsola in Asiatic desert-steppe areas. Ponomarev and Lykova themselves reported the existence of cleistogamy in Petrosimonia triandra (Pallas) Simonk and Salsola brachiata Pallas. However, they stated that cleistogamous flowers were actually no different structurally from chasmogamous ones, but rather, that the stamens in cleistogamous flowers simply did not become exserted (and consequently would shed pollen internally within the flower). They believed that cleistogamy could be quantified (on a percentage basis) merely by counting the number of flowers with included versus exserted stamens. From the preceding brief account, it is obvious that pollination biology in the Chenopodiaceae is much in need of investigation, or reinvestigation as the case may be. Such studies might well result in views of pollination mechanisms in the family substantially different from those currently held. Whereas it is probably true that certain major segments of the family, e.g., a number of species of Atriplex, are predominantly wind-pollinated systems, anemophily may in fact not prove to be the overpowering rule for the Chenopodiaceae as a whole. Entomophily unquestionably plays a role in some genera. Although entomophily may