MISSOURI BOT Research Articles

A Chemotaxonomic Classification of the Solanaceae

Alkaloids and steroids in the Solanaceae are reported extensively in the literature. By examining the biosynthetic routes leading to different alkaloids, the pathways can be visualized as a spiral from which the various compounds can be derived. Arrangement of the genera of Solanaceae according to their chemical contents in relationship to this spiral supports traditional classifications of the family, but the Anthocercidoideae and Atropoideae must be recognized as new subfamilies due to their biochemical synthesis syndromes. Similarly, Solaninae and Physalinae must be accepted as separate subtribes of tribe Solaneae because of their differing and exclusive steroid synthesis. Acnistus and Dunalia must be allied with Jaborosa in tribe Jaboroseae. Although solanaceous species are well known to afford an array of alkaloids and steroids, the family has not been arranged yet according to chemical features. Indeed, it is difficult to find reports of most features because, except for the occurrence of calcium oxalate crystals, only their absence is recorded. Thus Philipson (1977) concluded that a lack of iridioids characterizes the Solanaceae within the Unitegminae. Dahlgren (1975, 1980) came to similar conclusions, adding the deficiency of polyacetylenes as a characteristic. Sporne (1980) believed that absence of leucoanthocyanins and ellagitanins are chemical characteristics of the family and indicated that whether or not the seeds contain endosperm may or may not be significant. In an investigation of the cytochrome-C and plastocyanin amino acid sequence, Boulter et al. (1979) placed the Solanaceae far from the Asteraceae in their family tree, and although they related it closely to the Scrophulariaceae, they surprisingly considered the Caprifoliaceae to be the most closely related family. This biochemical statement supports the earlier view of Chadefaud & Emberger (1960) that the Solanaceae and Caprifoliaceae are closely related based on embryological characters. Nevertheless, mature solanaceous plants are typical alkaloid-accumulators, whereas mature caprifoliaceous plants have phenol-glycosides (Hegnauer, 1973). In the same publication Boulter et al. (1979) put the tomato alongside the potato and separated tobacco and the woody Solanum crispum Ruiz & Pavon, and they held Capsicum frutescens L. to be significantly different from the preceding species based on the amino acid complement. The use of active principles found in different Solanaceae to construct systematic schemes can be accepted only when it can be demonstrated that the biosynthetic routes leading to these chemical structures are homologous (Tetenyi, 1973). The valid chemical patterns are in the various biosynthetic pathways and not in the substances accumulated. Thus I have summarized the branching and relationships of biosynthetic pathways in alkaloid production in the Solanaceae in Table 1 and Figure 1. Numbers in the following paragraphs correspond to those of Table 1 and Figure 1. The first evidence supporting this scheme lies in the well-known, genetically determined chemical differentiation in infraspecific chemotaxa of Duboisia myoporoides R. Br. (Tetenyi, 1970). The characteristic active alkaloid ingredient, nicotine (1), in one chemotaxon of this species is the result of the synthesis of ornithine and tryptophan to an alkaloid. Another chemotaxon of D. myoporoides is characterized by a splicing of the aspartate pattern (lysine) and acetyl-CoA to the alkaloid biosynthesis, and the main alkaloids are then anabasine (A) and isopelletierine (B). In a third infraspecific chemotaxon, an entirely different pattern occurs: an ax-face nucleophilic attack instead of the f-face one of the N-methylAl-pyrrolinium salt (Fig. 2; Leete, 1979) leads to the pathways indicated by the solalkoid spiral (Fig. 1), that is, the linking of ornithine and acetyl-CoA to hygrine (2) and then the development I This paper was part of the Second International Symposium on the Biology and Systematics of the Solanaceae presented at the Missouri Botanical Garden on 3-6 August 1983. 2 Research Institute for Medicinal Plants, P.O. Box 11, 2011 Budakaldsz, Hungary. ANN. MissouRi BOT. GARD. 74: 600-608. 1987. This content downloaded from 157.55.39.175 on Thu, 11 Aug 2016 05:23:05 UTC All use subject to http://about.jstor.org/terms 1987] TETENYI-CHEMOTAXONOMIC CLASSIFICATION OF SOLANACEAE 601 TABLE 1. Alkaloids of Solanaceae included in and arranged conforming to the solalkoid spiral. Nicotine and its derivatives nicotine (1) anabasine (A) isopelletierine (B) CIOH14N2 CIOH14N2 C8H15NO [54-11-5] [494-52-0] [539-00-4]

Systematics of the Amphi-Atlantic Bambusoid Genus Streptogyna (Poaceae)

Streptogyna is the only herbaceous bamboo genus with an amphi-Atlantic distribution. Streptogyna crinita occurs in tropical Africa, Sri Lanka, and India, and S. americana is found throughout the Neotropics. Although marked differences in habit and in morphology of lodicules and starch grains suggest segregation at the generic level, they are here retained in a single genus because they are quite similar in spikelet morphology and leaf anatomy. Multicellular microhairs are present on the lodicules of S. crinita and mark the first report of microhairs in the genus. Multicellular microhairs are otherwise well developed in the grasses only in the African herbaceous bamboo Guaduella, and they may be a primitive feature in the family as they are common in its putative outgroup, the Joinvilleaceae. Streptogyna shows strong bambusoid affinities in its ligule and leaf anatomy, spikelet structure, caryopsis and embryo morphology, and chromosome number, but differs from the core group of the subfamily in its seedling morphology and lack of epidermal papillae. Autapomorphies in the two species suggest that neither could have been derived directly from the other. The genus Streptogyna was first brought to the attention of Western botanists in the late 18th century, when British and Swedish collectors brought back specimens of rat-catching grass from the forests of West Africa. A gathering from Nigeria by Palisot de Beauvois was used as the basis for Streptogyna in 1812, which he based on the only species known to him, S. crinita. The narrow leaves and many-flowered spikelets of Streptogyna were long taken as indications of pooid (festucoid) affinities. Thus, Bentham (1883), Hackel (1887), and Hubbard (1936) all considered that the proper disposition of this genus from the tropical rainforest lay with this large, temperate-region group. But there were dissenters, and Nees von Esenbeck (1835) and Steudel (1855), for example, suspected the bambusoid affinities of the genus. Streptogyna was briefly revised by Hubbard (1956), who indicated that the group deserved tribal status, but it was not until Tateoka (1958a) and Metcalfe (1960) examined its leaf anatomy that the bambusoid affinities of Streptogyna became clear. Recent workers agree that Streptogyna should be placed in its own tribe in the Bambusoideae (Calderon & Soderstrom, 1980; Clayton & Renvoize, 1986). In a treatment of the herbaceous bamboos of Sri Lanka, Soderstrom et al. (1987) offered a detailed descriptive account of the leafblade anatomy in the two taxa. The present study provides a revision of the genus and attempts to clarify the relationships of the two species by examining characters that have not yet been studied in detail, such as morphology of lodicules, starch grains, and embryos. MATERIALS AND METHODS Specimens of Streptogyna were examined from the following herbaria: AAU, B, BM, BR, CAY, CEPEC, F, G, ISC, K, M, MO, NA, NY, P, PDA, RB, S, US, W, and WIS. For anatomical studies, spikelets, leaves, and embryos (Table 1) were dehydrated in dimethoxypropane, infiltrated with tertiary butanol, embedded in wax, sectioned using a rotary microtome, and stained in chlorazol black E. Lodicules were rehydrated with AerosolOT before examination. Starch grains from caryopses were cut on a freezing microtome and stained with l2KI. Observations of living plants of Streptogyna were made by Soderstrom in Brazil (March 1972, and May 1976) and by Jud1 We are grateful to Alice R. Tangerini for the illustrations, to Stanley Yankowski for the floret sections, to the curators of the herbaria that lent us specimens for study, and to Gerrit Davidse, Lynn G. Clark, and Mary Sangrey. Part of the research leading to this paper was performed while the second author was a predoctoral fellow at the Smithsonian Institution. 2 Department of Botany, Smithsonian Institution, Washington, D.C. 20560, U.S.A. Died on September 1, 1987. 3Department of Botany, Smithsonian Institution, Washington, D.C. -20560, U.S.A. ANN. MISSOURI BOT. GARD. 74: 871-888. 1987. This content downloaded from 157.55.39.179 on Tue, 12 Apr 2016 09:52:13 UTC All use subject to http://about.jstor.org/terms 872 ANNALS OF THE MISSOURI BOTANICAL GARDEN [VOL. 74 TABLE 1. Specimens of Streptogyna for which embryos (e), floret bases (using the scanning electron microscope) (f), lodicules (1), and starch grains (s) were examined.

Flower Longevity and Protandry in Two Species of Gentiana (Gentianaceae)

Both Gentiana saxosa and G. serotina are protandrous. When flowers open, pollen is presented extrorsely around the closed stigma for one to six days. As the stigma opens, the stamens curve toward the corolla lobes. The length of the female phase, and therefore reproductive flower life, is determined by pollination, although in both species the corolla may remain fresh for longer than one month. Fresh female-phase flowers close at night and fail to reopen on the day following pollination. After five days in the female phase, flowers reacted less quickly to pollination and seed production was reduced; flowers pollinated on their tenth day of stigma presentation produced no seed although they appeared fresh. Senescence of unpollinated flowers differed between species: in G. saxosa the flowers remained open and gradually deteriorated, but in G. serotina the flowers eventually closed before full senescence. Pollination-induced flower senescence has been demonstrated for a number of other angiosperms, and the usual reactions to pollination are corolla abscission, color change, or wilting. In Gentiana, the closed corolla enfolds the large superior ovary and may serve to protect it from predators as well as prevent further pollinator visits. Pollination-induced flower senescence probably also minimizes flower maintenance costs by ensuring that the flower functions no longer than necessary. One correlate of this phenomenon in hermaphroditic flowers is protandry, which ensures pollen dispatch before flower closure. Floral senescence may be either time-dependent (endogenous) or exogenous (usually pollination-induced). However, there have been few detailed investigations of the factors that determine floral senescence, and hence, floral longevity (Primack, 1985). Most such studies have concentrated on corolla color changes or other physiological reactions that follow pollination and signal senescence (e.g., Arditti et al., 1973; Arditti, 1976; Gottsberger, 1971; Gori, 1983; Strauss & Arditti, 1984; Casper & La Pine, 1984; Halevy, 1984), and less attention has been afforded structural changes such as wilting, flower closure, and corolla abscission (Mayak & Halevy, 1980). Most of this research is concerned with the proximate determinants of floral longevity rather than the evolution of particular responses (but see Stead & Moore, 1979; Gori, 1983; Casper & La Pine, 1984; Devlin & Stephenson, 1984). The paucity of research on the evolutionary aspect of flower senescence is somewhat surprising, because pollination-induced senescence in particular may have important consequences for the pollination system and ultimately for the plant's overall reproductive strategy. For instance, in hermaphrodite flowers pollination-induced flower senescence will limit the duration of pollen and stigma presentation and so may influence or be influenced by the extent and nature of dichogamy (Lloyd & Webb, 1986). New Zealand species of Gentiana (in the southern group of Philipson, 1972) are protandrous (Thomson, 1881; Simpson & Webb, 1980; Webb, 1 984a). Their large, relatively simple flowers make them particularly suitable subjects for experimental studies of flower function. This paper describes the response of flowers of two species to pollination and reports the results of experiments to determine the functional duration of male and female phases in terms of pollen presentation and seed production. MATERIALS AND METHODS The two species of Gentiana selected were those that grew best in cultivation. Gentiana saxosa Forster f. grows naturally in coastal sites of southern South Island and Stewart Island, New Zealand; plants were collected from Curio Bay, Southland. Gentiana serotina Cockayne occurs in grassland in inland central South Island; plants were collected from Lake Lyndon, Canterbury. The plants were grown in clay pots in an insectproof cage in greenhouses at Lincoln, Canter1 We thank I. C. Brown and garden staff at Lincoln, Canterbury, for maintaining the plants in cultivation, J. Miles for assistance with photographs, and P. Brooke for drawing Figures 2 and 3. We are grateful to L. F. Delph-Lively, E. Edgar, and D. G. Lloyd for comments on a draft of the manuscript. 2 Botany Division, Department of Scientific and Industrial Research, Private Bag, Christchurch, New Zealand. ANN. MISSOURI BOT. GARD. 74: 51-57. 1987. This content downloaded from 157.55.39.144 on Mon, 25 Jul 2016 04:48:36 UTC All use subject to http://about.jstor.org/terms 52 ANNALS OF THE MISSOURI BOTANICAL GARDEN [VOL. 74 TABLE 1. Results of controlled pollinations to determine self-compatibility in Gentiana saxosa and G.

Siphocampylus oscitans (Campanulaceae: Lobelioideae), A New Name for Burmeistera Weberbaueri from Peru

Burmeistera weberbaueri is transferred to the genus Siphocampylus under the new name Siphocampylus oscitans. The species is noteworthy in being one of only three species of Siphocampylus known to have a dilated anther-tube orifice. As part of a reassessment of the Peruvian members of Burmeistera (Stein, 1987), it has become apparent that B. weberbaueri Zahlbr. actually belongs to the large Andean genus Siphocampylus. This paper makes the appropriate generic transfer and proposes a new name to accommodate this unusual species. Generic delimitations in Campanulaceae subfamily Lobelioideae have long been recognized as problematic (Gleason, 1925; McVaugh, 1940). Traditional systems, such as those of Presl (1836) and Wimmer (1943), rely heavily on fruit morphology for classification at the tribal level. In particular, capsular versus baccate fruit is a fundamental character used to define and align genera. Strict reliance on this dichotomy in the classification ofthe subfamily has separated close relatives, for example, capsular-fruited Siphocampylus and baccate-fruited Centropogon. Although fruit type in conjunction with other features can be reliable for clustering related groups of species, probable convergence in fruit characters suggests caution in its application. Among neotropical Lobelioideae the emphasis on fruit type, and to a lesser degree on the presence or extent of a dorsal slit in the corolla (another seemingly labile character), has yielded _genera .of convenience. -aOze of-the most natural groupings, however, appears to be the genus Burmeistera, which is characterized by baccate fruits, oblong or linear seeds, mostly nonbracteolate pedicels, entire corolla tubes, and distally open and oblique anther tubes often with little or no apical pubescence. The distally open anther tube of Burmeistera is one of its most distinctive features. In most genera of Lobelioideae the three dorsal anthers are longer than the two ventral ones and curve downward at the apex, effectively closing the mouth of the anther tube. This allows the internally released pollen to build up pressure as the style and stigma elongate, pushing pistonlike through the anther tube. The characteristic tuft of stiff hairs at the tip of the ventral anthers functions as a lever that opens the orifice slightly and allows the pressurized pollen to discharge. Presumably tripped by flower visitors, this action has been elegantly documented in Isotoma petraea by Brantjes (1983) and has been observed in the neotropical genera Centropogon and Siphocampylus (Stein, in prep.). Since the dorsal anthers in Burmeistera do not curve downward closing the anther tube, this type of regulated pollen discharge does not occur. This difference in pollen presentation probably explains the correlated feature of glabrous or only sparsely pilose anther apices in Burmeistera sect. Imberbes F. Wimmer: apical hairs there have no function as trip mechanisms. Whether the densely villous tuft at the tip of the ventral anthers in Burmeistera sect. Barbatae F. Wimmer has a functional role -in.pollen d-ischarge is not clear. Burmeistera weberbaueri was included in this genus by Zahlbruckner (1906) on the basis of floral features alone, as he had no mature fruit. This decision was probably based upon his observation of a naked and dilated anther-tube orifice, the absence of bracteoles, and the somewhat I I am grateful to Carlos Reynal for locating the type specimen at MOL and to B. E. Leuenberger for searching for type material at B. Dan H. Nicolson kindly provided advice regarding lectotypification, and Porter P. Lowry II and Peter Goldblatt made useful suggestions on-an earlier draft. Fieldwork in Peru was supported by National Science Foundation Doctoral Dissertation Improvement Grant BSR84-13912 and by a Garden Club of America Award in Tropical Botany. 2 Missouri Botanical Garden and Washington University. P.O. Box 299, St. Louis, Missouri 63166-0299, U.S.A. ANN. MissouRI BOT. GARD. 74: 491-493. 1987. This content downloaded from 207.46.13.43 on Wed, 25 May 2016 04:52:59 UTC All use subject to http://about.jstor.org/terms 492 ANNALS OF THE MISSOURI BOTANICAL GARDEN [VOL. 74 burmeisteroid corolla morphology (a short, straight tube with an abruptly ampliate throat and falcate lobes). The strongly turbinate hypanthium visible in the Field Museum type photograph suggests the mature fruit of this species to be capsular rather than baccate. Furthermore, the coriaceous and rugose texture of the leaves characterizes many members of Siphocampylus but is unknown in Burmeistera. An open anthertube orifice of the kind described by Zahlbruckner is, however, extremely rare in Siphocampylus.

Fossil Evidence Regarding the Evolution of Nothofagus Blume

Information on fossil Nothofagus, and related genera, is reviewed based on pollen grains, leaves, woods, and flowers and fruits. The available data suggest that ancestors of Nothofagus and related families probably originated in West Gondwanaland. By the Santonian, Nothofagus was the only living genus already differentiated in the southern Hemisphere. Northern counterparts included several species in living genera of the Betulaceae, Myricaceae, and Ulmaceae. Rapid evolution and speciation of Nothofagus took place in the Eocene. After the pollen types and the main leaf forms were established in the Cretaceous and Eocene, respectively, the rate of morphological change was slow. More speciation was possible after the Miocene in New Guinea and also in other areas during the Plio-Pleistocene. Several lines of evidence support former suggestions of giving Nothofagus a higher taxonomic rank. Nothofagus Blume has frequently captured the interest of botanists and paleobotanists. It plays a dominant role in the temperate forests of the Southern Hemisphere, has economic importance as a timber source, and has an intriguing distribution as a vicariant of the other genera in Fagaceae. It comprises 34 species living in South America, Australia, New Zealand, New Caledonia, and New Guinea. It certainly lived in Antarctica, but perhaps never in South Africa. The Fagaceae are usually associated with the Betulaceae in the order Fagales (Thorne, 1983; Takhtajan, 1980), sometimes including also the Balanopaceae (Cronquist, 1968). Other related orders are Didymelales, Casuarinales, Myricales, and Hamamelidales, all included in the subclass Hamamelidae. Although this subclass has been subjected to considerable systematic rearrangement (Thorne, 1973), the taxa mentioned above were not very much affected. The Fagaceae have been segregated into three subfamilies since De Candolle (1864), and this classification has been supported by modern studies such as those of Forman (1966) and Hjelmqvist (1948) on the female cupule. The only objection has been the proposal to segregateNothofagus as a new family, made by Kuprianova (1965), on the basis of the pollen grains. More recent support for some kind of segregation was advanced by Crepet and Daghlian (1980), Smiley and Huggins (1981), Thorne (1983), Nixon (1984), and Jones (1984b). The classification of the species of Nothofagus into two sections and four series was suggested by van Steenis (1953) and Soepadmo (1972) on the basis of the female cupule and vegetative morphology. Recent information does not support fully such an arrangement (Elias, 1971; Philipson & Philipson, 1979; Hill, 1983), but no alternative system has been proposed. In recent years a growing body of information has accumulated about fossil materials of Nothofagus and related genera, shedding some light on its history and phylogenetical development. This information has not been fully used, and speculation about the evolution and paleobiogeography of the genera has been based mainly on the evidence of living plants (van Steenis, 1971; Darlington, 1965; Melville, 1973, 1981; Cracraft, 1975; Humphries, 1981, 1985; Heads, 1985). Therefore, it seems reasonable to review information concerning fossil forms. Modern and fossil data are reviewed first in this paper, followed by a discussion. The review of fossil data is arranged by type of fossil (pollen, leaves, woods, and flowers and fruits). In each case, a brief statement about their morphology in living plants is given. The discussion starts with the Cretaceous history of the genus, and also deals with the fossil record of related families. Then, the Paleogene account comprises the differentiation of species within the genera, so the morphology of the living ones is also considered. Finally, the Neogene part deals mainly with biogeography, and the information concerns primarily living plants. The fossil evidence was compiled by Wolfe (1973) and Muller (1981). When some information is given without menI Departamento de Ciencias Biol6gicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Intendente Guiraldes 2620, 1428 Buenos Aires, Repfiblica Argentina. Member of Consejo Nacional de Investigaciones Cientificas (CONICET). ANN. MISSOURI BOT. GARD. 73: 276-283. 1986. This content downloaded from 157.55.39.211 on Tue, 09 Aug 2016 05:15:09 UTC All use subject to http://about.jstor.org/terms 1986] ROMERO-NOTHOFAGUS EVOLUTION 277 tioning the source, it may be found in these reviews. However, in important cases the original publication is given. Other more recent papers, or ones not considered by Wolfe or Muller, are quoted as well. The references to paleogeography are based on Smith et al. (1981) and those to age are based on Harland et al. (1982).

Serotaxonomy of Solanum, Capsicum, Dunalia, and Other Selected Solanaceae

Serotaxonomic comparisons were made on about 50 species of Solanaceae. Immunoabsorption data were obtained from reactions of seed protein antigen systems with antibody systems absorbed by several antigen systems in numerous permutations. Relationships of the taxa were computed by newly developed methods. Twenty species of Solanum, mostly of subg. Leptostemonum, were compared using six antisera. Solanum nigrum (subg. Solanum) was serologically distinct from the others. Several groups of species belonging to different sections of Solanum were recognized. Phenetic and phyletic relationships within sect. Androceras were explored. Re-analysis of a complete cubic matrix of immunoabsorption data for eight species of Solanum rearranged relationships slightly but emphasized the divergence between different sections of this genus. A broad survey was made using an antibody system raised to Capsicum annuum. This revealed the distinctiveness of Nicandra from other Solanaceae, several possible inter-generic relationships, but also some unlikely ones. Further studies revealed closer relationships of Dunalia species to Capsicum than to Iochroma. Protein characters are valuable in plant taxonomy for assessing inter-generic and even interfamily relationships (Jensen & Fairbrothers, 1983). Within the Solanaceae several serological studies have been made by workers such as Chester, Hammond, Tucker, Gray, and Lester (see review by Lester, 1979). Because of the complex physico-chemical properties of proteins, and the even more complex phenomena of immunological reactions, many different serotaxonomic techniques have been developed (Jensen & Fairbrothers, 1983). Immunoabsorption resolves subsets of antigenic determinant sites as recognized by corresponding subsets of antibodies after the removal of common antibodies from the antibody system by absorption by other antigen systems. Recent developments in the theoretical and practical aspects of immunoabsorption techniques and the analysis of the resultant data by appropriate numerical taxonomic procedures have been discussed in detail (Lester, 1979; Lester et al., 1983). For this paper these procedures were applied to selected species of Solanaceae. MATERIALS AND METHODS Seed samples from the Birmingham University Solanaceae Collection (Tables 1-3) were used to prepare protein extracts, to induce antibody production in rabbits, and for subsequent immunological experiments using absorbed antibody systems. Procedures, especially the scoring and analysis of results, followed those described by Lester (1979) and Lester et al. (1983). Three sets of experiments were conducted. 1. Twenty accessions of Solanum, mostly of subg. Leptostemonum (Table 1) were compared using six antibody systems (data published in Lester et al., 1983). 2. Eight species from diverse sections of the genus Solanum (Table 2) were compared using eight antibody systems (data published in Lester, 1979). 3. About 25 species of Capsicum, Solanum, and other genera of Solanaceae, mostly of tribe Solaneae (Table 3) were compared using one antibody system (Lester, unpubl. data). Most of these data have now been analyzed by most of the procedures described by Lester et al. (1983), especially by using Jaccard's and similar coefficients to estimate phenetic relationships. Some of the data sets also were subjected to cladistic analysis. Many dendrograms were produced by different analyses of the various sets and subsets of data, some of which are presented herein (Figs. 1-6). I We are grateful to Sarah Marsh for growing these plants, to the Science and Engineering Research Council (U.K.) for financial support, and to Julie Brean, Barbara Klauza, and Sarah Sutton for technical assistance. 2 This paper was part of the Second International Symposium of the Biology and Systematics of the Solanaceae presented at the Missouri Botanical Garden on 3-6 August 1982. 3 Department of Plant Biology, University of Birmingham, Edgbaston, Birmingham B1 5 2TT, England. 4 Department of Nematology, University of California, Riverside, California 92521. ANN. MISSOURI BOT. GARD. 73: 128-133. 1986. This content downloaded from 207.46.13.60 on Thu, 21 Apr 2016 07:28:58 UTC All use subject to http://about.jstor.org/terms 1986] LESTER & ROBERTS-SOLANACEAE SEROTAXONOMY 129 TABLE 1. Listing and classification of the 20 accessions of Solanum species that were compared immunologically using antibody systems to CAP, ROS, SIS, QUT, TOR, and PRN.

Sudanian Elements in the Flora of Israel

In the Dead Sea Rift Valley of Israel, a northern tongue of penetration of Sudanian elements exists that has traditionally been regarded as composed of Miocene relicts. We postulate that most of these elements have penetrated the area since the end of the Pleistocene. The principal habitats harboring Sudanian elements in Israel are described, including the pseudo-savanna in wadi beds, cliffs and rock formation, oases and in the Dead Sea Rift as well as a variety of secondary habitats outside the Rift. In addition, a statistical analysis of the 116 species in the flora of Israel considered to be Sudanian elements is presented, covering growth form, phytogeographic distribution, dispersal mechanisms, and degree of endemism. Special attention is given to the arboreal elements, including 49 species of trees, shrubs, and perennial vines. A comparison is made between the habitats of these species in East Africa and in Israel: significant habitat shifts were found in some cases. Although paleo-macrofossils are almost non-existent in the area, other evidence, such as low degree of endemism, disjunctiveness, and adaptations to aridity and long-distance dispersal indicate that the great majority of the Sudanian elements in the Dead Sea Rift are of recent origin. The relationships between the typical evergreen Mediterranean elements with paleotropical origins and the extant Sudanian elements in Israel are discussed. Within the portion of the Syrian-African Rift lying between the Red Sea to the south and the watershed of the Jordan River in the Golan Heights, a large number of Sudanian elements, plants as well as animals, are found considerably farther north than anywhere else in their distribution range and in many cases growing under ecological conditions quite different from their norm. In addition, a handful of Sudanian species also occur in the low-lying coastal plain of Israel, almost entirely cut off from the Dead Sea Rift Valley and the bulk of the Sudanian region proper (Fig. 1). Climatic and geological conditions in the Dead Sea Rift Valley explain in part the presI A. Shmida wishes to express his considerable debt of gratitude to the late Prof. M. Zohary who introduced him (and dozens of other students) to the intricacies and unique attributes of the Israeli flora. We thank G. E. Wickens who reviewed the manuscript with meticulous care, helped gather information for some of the distribution maps, and made valuable suggestions for improvement of the text. J. B. Gillett and P. Quezel also kindly reviewed the manuscript and provided stimulating comments and suggestions. Our thanks also go to Sandy Greenberg, Seemah Shemesh, and Marion Milner who provided computer and typing assistance, to Nancy R. Morin and Dr. Marjorie Tiefert for patient and professional editorial guidance, and to Miri Shmida who drew the figures. The assistance of J. Dransfield in preparing Figure 5 is gratefully acknowledged. Any errors or inaccuracies therein are entirely the responsibility of the authors. Finally we thank the numerous guides of the Israeli Society for the Protection of Nature who helped us locate some of the rare and little-known populations of Sudanian plants in Israel. We gratefully acknowledge financial assistance received during the course of this research from the Bath-sheva de Rothschild Fund to A. Shmida and the Clifford M. Hardin Fund of the Fund for Higher Education to J. A. Aronson. 2 Department of Botany, The Hebrew University of Jerusalem, Jerusalem, Israel. 3Rudolf and Rhoda Boyko Institute for Agriculture and Applied Biology, Institutes for Applied Research, Ben-Gurion University of the Negev, P.O. Box 1025, Beer-Sheva 84110, Israel. ANN. MissouRi BOT. GARD. 73: 1-28. 1986. This content downloaded from 157.55.39.253 on Sat, 11 Jun 2016 07:14:14 UTC All use subject to http://about.jstor.org/terms 2 ANNALS OF THE MISSOURI BOTANICAL GARDEN [VOL. 73

Augustus Fendler (1813-1883), Professional Plant Collector: Selected Correspondence with George Engelmann

Augustus Fendler (1813-1883), Professional Plant Collector: Selected Correspondence with George Engelmann

Three New Species of Solanum Section Geminata (G. Don) Walp. (Solanaceae) from Panama and Western Colombia

Three New Species of Solanum Section Geminata (G. Don) Walp. (Solanaceae) from Panama and Western Colombia

Evolution and Reproductive Biology of Inflorescences in Lithocarpus, Castanopsis, Castanea, and Quercus (Fagaceae)

Of Lithocarpus, Castanopsis, Castanea, and Quercus only Lithocarpus frequently bears branched spikes suggestive of the primitive condition in the Fagaceae; the other genera sometimes have them in some individuals. Simple and branched spikes can occur on the same tree. Evolution of the simple spike is interpreted as the loss of branching capacity in the branched spikes. The Fagaceae show various transitional stages from perfect, entomophilous to imperfect, anemophilous flowers and from mixedsex to unisexual spikes. Complete separation of staminate from pistillate function into separate spikes and catkins occurs only in Quercus, which is also the only anemophilous member of these four genera. Lithocarpus is the least specialized while Quercus is the most specialized in inflorescence structure of the four genera. Pathways of inflorescence evolution in Castanea, Castanopsis, Lithocarpus, and Quercus have been proposed that identify Lithocarpus and Quercus as possessing the least and most specialized inflorescences, respectively (Kaul & Abbe, 1984). The specialized inflorescence character states of Quercus are associated with anemophily and the less specialized states in Lithocarpus, Castanea, and Castanopsis relate to their entomophily (Kaul, 1985). Kaul et al. (1986) suggested that the evolution of anemophily in Quercus [and probably also in another fagaceous species, Trigonobalanus daichangensis (Camus) Forman] was an adaptation for successful pollination in seasons of low pollinator activity in seasonal climates, for example, spring in the temperate latitudes. In such latitudes the anemophilous Fagaceae Quercus and Fagus flower briefly in the spring whereas the entomophilous Castanea and northerly species of Castanopsis and Lithocarpus flower over a longer period in early summer. Likewise, flowering peaks in entomophilous paleotropical Fagaceae (Castanopsis, Lithocarpus) coincide with maximum insect activity (Kaul et al., 1986; cf. Fogden, 1972). Quercus, which is anemophilous throughout its range, flowers at various times in the tropics but not in the wettest seasons. Further evidence of the functional aspects of these inflorescences is scanty, and therefore definitive answers to questions about the ancestry and subsequent functional evolution of fagaceous inflorescences must be sought through comparative studies of living and fossil taxa. In these genera the spikes and catkins usually bear numerous sessile, subsessile, or, in a few instances, pedunculate flower clusters that are variously called dichasia, cymules, or partial inflorescences. They are the only structures that presumably terminate in a flower in these four genera; all other structures-branches, rachises, spikes, and catkins-apparently terminate in a vegetative bud that may or may not be capable of further growth. The dichasia are surely derived by phylogenetic condensation and the ancestral inflorescences were probably thyrse-like or panicle-like. Some modem Fagaceae, most notably some species of Lithocarpus, produce branched spikes that are themselves aggregated into manybranched inflorescences of higher orders, resulting in the most complex floral displays in the family. The ancestral fagaceous inflorescence was no doubt more complex than any modem inflorescence in the family. Fey and Endress (1983) have advanced credible evidence that the cupule of the fruit is itself a product of condensation of dichasial branching systems. Further, Hjelmqvist (1948) interpreted some staminate flowers as pseudanthia. Kaul and Abbe (1984) suggested evolutionary changes in fagaceous inflorescences that included loss of syllepsis in both vegetative and reproductive shoots and separation of staI Research supported by National Science Foundation grants DEB-7921641 and DEB-8206937. 2 School of Biological Sciences, University of Nebraska, Lincoln, Nebraska 68588-0118. ANN. MISSOURI BOT. GARD. 73: 284-296. 1986. This content downloaded from 157.55.39.17 on Fri, 02 Sep 2016 04:42:57 UTC All use subject to http://about.jstor.org/terms 1986] KAUL-FAGACEAE INFLORESCENCES 285 minate from pistillate flowers in the total inflorescence. We also suggested that the catkins of anemophilous Fagaceae were derived from spikes of entomophilous ancestors and that there is a rough gradient of decreasing inflorescence complexity with increasing latitude. In our previous papers (Kaul & Abbe, 1984; Kaul, 1985) some complex fagaceous inflorescences were described and illustrated. Here I elaborate upon our work, illustrate additional examples of complex inflorescences, and provide further evidence for their interpretation as the least specialized forms among extant Fagaceae. It must be emphasized that even the least specialized extant forms are advanced for angiosperms as a whole, as evidenced by the presence of such extreme reductions as dichasia and cupules in every species.

Convergent Evolution of the 'Homeria' Flower Type in Six New Species of Moraea (Iridaceae-Irideae) in Southern Africa

Convergent Evolution of the 'Homeria' Flower Type in Six New Species of Moraea (Iridaceae-Irideae) in Southern Africa

Morphology and Development of Pistillate Inflorescences in Extant and Fossil Cercidiphyllaceae

Morphology and Development of Pistillate Inflorescences in Extant and Fossil Cercidiphyllaceae

Cytology and Systematics of the Moraea fugax Complex (Iridaceae)

Cytology and Systematics of the Moraea fugax Complex (Iridaceae)

Notes on the Systematics of Hesperantha (Iridaceae) in Tropical Africa

Notes on the Systematics of Hesperantha (Iridaceae) in Tropical Africa

New Neotropical Species of Meliosma (Sabiaceae)

New Neotropical Species of Meliosma (Sabiaceae)

Studies in the Araliaceae of Nicaragua, and a New Widespread Species of Oreopanax

Studies in the Araliaceae of Nicaragua, and a New Widespread Species of Oreopanax

Miocene Fossil Grasses: Possible Adaptation in Reproductive Bracts (Lemma and Palea)

Fossil reproductive bracts of Berriochloa, Nassella, and Paleoeriocoma of the tribe Stipeae, Archaeoleersia of the tribe Oryzeae, and Panicum of the tribe Paniceae (Gramineae) were collected from late Oligocene-Miocene strata in central North America, examined, and compared with modem taxa. One objective of these studies was to elucidate the evolution and possible adaptive significance of bract features. Berriochloa, the oldest known grass, appears in late Oligocene-early Miocene strata, where it has an indurate, cylindrical anthoecium (lemma and palea collectively) and an elongated, pointed callus. From early Miocene forms of Berriochloa two mid-late Miocene lineages evolved, one retaining a cylindrical anthoecium and the other developing a prominently inflated anthoecium. Both lineages retained the elongated, pointed callus. Paleoeriocoma, Nassella, Archaeoleersia, and Panicum first appear in the late Miocene with anthoecia similar to those of living taxa. The indurate anthoecium of the fossil and related living grasses probably evolved primarily as an adaptation to mammals and insects that use grasses as food. Related living taxa show adaptive mechanisms similar to those of the fossils, although some features such as the strongly interlocking bracts and blunt callus of some species of Piptochaetium are a post Miocene development. The Tertiary deposits of central North American Plains have produced rich and varied floras of considerable paleobotanical interest (Stansbury, 1852; Engelmann, 1876; Cockerell, 1914; Berry, 1928; Elias, 1931, 1932, 1934, 1935, 1942; Frye et al., 1956, 1978; Leonard, 1958; Leonard F Frye L Segal, 1965, 1966a, 1966b, 1966c; Skinner et al., 1968; Galbreath, 1974; Diffendal et al., 1982; Voorhies & Thomasson, 1979). Grasses in these floras are found as silicified reproductive bracts or as remains of leaves, stems, and roots and frequently exhibit detailed epidermal features that aid in determining phylogenetic relationships of fossils and their modem counterparts (Thomasson, 1976, 1977, 1978, 1979, 1980a, 1980b, 1984). Fossils described include reproductive bracts assigned to Archaeoleersia of the tribe Oryzeae, Berriochloa, Nassella, and Paleoeriocoma of the tribe Stipeae, and Panicum of the tribe Paniceae and leaf fragments assigned to the subfamilies Festucoideae and Arundinoideae. This paper presents results of my studies of the reproductive bracts (lemma and palea) or bract (lemma) enclosing the mature grain or caryopsis of fossil grasses and their related living taxa. It reviews the geologic and paleoecologic background, summarizes the morphologic features of the fossil and living grasses, examines evolutionary trends among the fossil grasses, and speculates on the adaptive significance of features seen in fossil and living grasses. GEOLOGIC AND PALEOECOLOGIC BACKGROUND The late Tertiary (Oligocene-Pliocene) strata of the central part of North America are a widespread group of continental sediments extending from North Dakota and Wyoming to Texas and New Mexico that were deposited principally in fluvial and aeolian environments. They consist of a large variety of sediments including clays, silts, sands, conglomerates, freshwater diatomites, and volcanic ashes and vary in thickness in individual sections from more than 200 m to 1 m. Although some early studies suggested rather simple models of deposition and biostratigraphy, more recent investigations have demonstrated their depositional and biostratigraphic complexity (Bart, 1975; Breyer, 1976, 1981; Skinner et al., 1968, 1977; Swinehart, 1979; Thomasson, 1979; Diffendal, 1980, 1982). Among the most richly fossiliferous Tertiary strata in the world, they contain assemblages of 1 This paper is one result of some studies that have been supported by the National Geographic Society (188379, 2197-80) and the National Science Foundation (DEB-7809150, DEB-800228 1, DEB-820468 1, CDP-8000918, and R1 1-8213915). I thank numerous colleagues and assistants who contributed their time and expertise in the field during these studies and N. Morin, P. Palmer, and anonymous reviewers for helpful suggestions that improved this paper. 2 Department of Biological Sciences, Fort Hays State University, Hays, Kansas 67601-4099. ANN. MISSOURI BOT. GARD. 72: 843-851. 1985. This content downloaded from 157.55.39.215 on Sun, 24 Jul 2016 04:34:41 UTC All use subject to http://about.jstor.org/terms 844 ANNALS OF THE MISSOURI BOTANICAL GARDEN [VOL. 72 TABLE 1. Stratigraphic relationships and ages of late Tertiary strata and study sites in the plains of central

Adaptation of Grasses to Water Stress-Leaf Rolling and Stomate Distribution

Leaf dimension, degree of leaf rolling or folding, and stomatal densities on adaxial and abaxial leaf surfaces were measured on herbarium specimens of 39 grass species from a range of dry to wet habitats in western Canada. Stomata were counted on vinyl leaf impressions taken from the herbarium specimens. Representative surfaces also were examined using scanning electron microscopy. All species from dry habitats had narrow rolled or folded leaves (4 mm or less). The proportion of stomata on the abaxial surface of species from dry habitats ranged from 0 to 65%, but 56% of the species were strongly amphistomatous. The results were compatible with a conceptual model predicting that rolling, amphistomatous leaves would be selected for habitats in which water supply and demand fluctuate widely on seasonal or diurnal time scales. The evolutionary adaptation of grasses involves a syndrome of physiological, anatomical, and morphological characteristics. Grass leaf structure is closely coupled with major physiological processes such as photosynthesis, water relations, and energy balance. For example, vascular bundle and mesophyll cell arrangement are related to the type of photosynthetic pathway (Black et al., 1973; Hattersley & Watson, 1975), which, in turn, can influence niche separation in grasses (Monson et al., 1983). Specialized leaf tissue structure in some grasses results in leaf rolling, which strongly influences water and energy balances by changing the characteristic leaf dimension and the conductance of heat, water vapor, and carbon dioxide (Ripley & Redmann, 1976). This paper concentrates on the relationship between leaf rolling and stomatal distribution and conductance. The anatomy and mechanism of leaf rolling in grasses have been studied for over a century (Tschirch, 1882; Shields, 1951). Loss of turgor in the bulliform cells on the adaxial (upper) surface generally is considered to induce rolling. Shrinkage of the adaxial subepidermal sclerenchyma and mesophyll, due to water loss, also contributes to involution; rolling can occur in leaves that lack bulliform cells (Shields, 1951). Some grasses have permanently rolled or folded leaves. Leaves of native grasses from semi-arid grassland roll in response to increased plant water stress during dry periods (Ripley & Redmann, 1976). More mesic grasses such as cereal crops also exhibit leaf rolling when exposed to water stress (Hurd, 1976; O'Toole et al., 1979). Leaves of Sorghum bicolor roll and unroll in response to diurnal changes in plant water status, provided stress is not too severe (Begg, 1980). The early textbooks on plant ecology generally explained rolling as a xeromorphic adaptation for reducing transpiration by protecting the stomata, which were considered to be concentrated on the upper surface (Warming, 1909; Weaver & Clements, 1929; McDougall, 1949). Unfortunately, references to data supporting this explanation were not given, but the idea probably originated with early work on ecological plant anatomy. Tschirch (1882) classified grasses as meadow type, with flat leaves, or steppe type, with rolling leaves. Lewton-Brain (1904) grouped British grasses into four categories representing progressively more drought resistant types: (1) leaves with flat upper surfaces, amphistomatous, (2) leaves with ribbed upper surfaces, amphistomatous, (3) leaves with ridged upper surfaces, rolled with drying, epistomatous, and (4) leaves permanently rolled or folded, epistomatous. I was unable to find published comparative data on relative stomatal distributions on grass leaves in relation to rolling or drought resistance that would verify the generalizations described above. Parkhurst (1978) pointed out that the limited data in the literature show no clear trends 1 This research was supported by a Natural Science and Engineering Research Council of Canada grant. Thanks go to G. Shaw who did the electron microscopy work using facilities in the Department of Biology, University of Saskatchewan. V. L. Harms contributed valuable discussion regarding drought resistance classification. 2 Department of Crop Science and Plant Ecology, University of Saskatchewan, Saskatoon S7N OWO, Canada. ANN. MISSOURI BOT. GARD. 72: 833-842. 1985. This content downloaded from 207.46.13.153 on Fri, 05 Aug 2016 06:11:51 UTC All use subject to http://about.jstor.org/terms

Chromosome Numbers in Compositae, XV: Liabeae

Chromosome Numbers in Compositae, XV: Liabeae

Geological Hierarchies and Biogeographic Congruence in the Caribbean

Geological Hierarchies and Biogeographic Congruence in the Caribbean