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Tribe Fabeae consists of five genera, Lathyrus (160 spp.), Lens (4–6 spp.), Pisum (2–3 spp.), Vavilovia (monotypic), and Vicia (160 spp.), and shows a diversity in stylar features. At least six different stylar types are known in the tribe. In order to reclassify the tribe at the rank of genus, we tried to discover apomorphies in stylar features using a molecular phylogenetic study. We surveyed internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA of representative species, selected from each group having different types of styles in the tribe. We paid particular attention in sampling to members of Vicia section Vicilla, as stylar features are heterogeneous within this section. Consequently, our sample set included 15 species of section Vicilla, 23 species of other Fabeae, and two species of Trifolieae, which were used as a sister group of Fabeae. Based on our analysis, we found that a laterally compressed style and an abaxially tufted hairy style would be advanced against a dorsiventrally compressed style and an evenly hairy style, respectively, in genus Vicia. The species group, which shares the latter apomorphy, is composed of 56 species and was dispersed into 11 sections of two subgenera in the recent system of genus Vicia. We consider future revision of Fabeae should treat this species group as a single higher taxon.

Larvae of 14 species and pupae of 12 species of Palaearctic Tychius Germar, 1817 are described for the first time. Larvae and pupae of T.meliloti Stephens, 1831, T. squamulatus Gyllenhal, 1835 and T. quinquepunctatus (Linnaeus, 1758), are redescribed with addition of new characters. They belong to 10 of 22 groups of species assembled through adult morphological characters in this region and, like all other Tychius with known biology, the studied species live on Leguminosae Papilionoideae, belonging to the tribes Genisteae, Loteae, Galegeae, Trifolieae and Vicieae. Generally larvae, but not pupae, show a few characters useful to support some groupings previously postulated on adult morphology, and also suggest some phylogenetic relationships among groups although these are partly weak because of several clear parallelisms or convergences. One of the most numerous and better known group of species, the T. stephensi group living on Trifolieae, is supported by two distinctive larval character states, whereas all the other groups seem to be distinguishable from each other at least by a unique larval character state. New bionomic data concerning larval and pupal development and adult emergence are reported for all the described species. These data confirm that this genus is highly homogeneous in habits and times of development, with unique adaptive differences in adult emergence and overwintering according to the single or double seasonal flowering of the host plant. On the basis of morphological characters of immatures and adults, a possible concordance between the evolution of Tychius and that of their host plants is discussed.

Trigonella suavissima Lindl. is an Australian native legume belonging to the tribe Trifolieae. It is an ephemeral species that is widely distributed in the arid interior of the continent where it occurs, following periodic inundation, on clay soils of the watercourse country of the Channel Country (far-western Queensland, north-east South Australia and north-western New South Wales). T. suavissima is the only member of its tribe that is endemic to Australia. Likewise, its root-nodule bacteria (Sinorhizobium sp.) may be the only member of its taxonomic group (S. meliloti, S. medicae) that is an Australian native. The distribution and frequency of occurrence of T. suavissima and the size of soil populations (density) of Sinorhizobium were monitored at 64 locations along inland river systems of the Channel Country. Measurements were made of (i) the nitrogen-fixing effectiveness of the symbioses between T. suavissima and strains of its homologous Sinorhizobium and (ii) the nitrogen-fixing effectiveness of the symbioses between legumes symbiotically related to T. suavissima and diverse strains of Sinorhizobium. It was concluded that the distribution and frequency of occurrence of T. suavissima is soil related. The species is most widespread on fine-textured clay soils with deep, self-mulching surfaces and high moisture-holding capacity. By contrast, the occurrence of T. suavissima is sporadic in the upper reaches of the inland river systems where the soils are poorly structured clays with lower moisture-holding capacity. Sinorhizobium is most abundant where the plant is most common. The nitrogen-fixing symbioses between T. suavissima and strains of Sinorhizobium isolated from soils across the region were consistently effective and often highly effective. Some of these strains fixed a little nitrogen with lucerne (Medicago sativa L.). T. suavissima also had some symbiotic (nitrogen-fixing) affinity with an exotic Trigonella (T. arabica Del.). The economic value of T. suavissima (and its symbiosis with Sinorhizobium) to the beef industry in the Channel Country is discussed.

A systematic investigation of the host range of a monouredinial isolate (KR1-1) of Uromyces striatus from alfalfa (Medicago sativa) was undertaken. The extent of susceptibility to this pathogen within plant tribes closely related to alfalfa was determined. A total of 844 plant introductions, representing 345 species or subspecies from 27 genera, was tested. The plants tested included representative species from the tribe Trifolieae (which includes alfalfa) and seven additional tribes closely related according to current phylogenetic descriptions of the Leguminosae. Six of the eight tribes contained genera with susceptible species that supported urediniospore production. A total of 141 species or subspecies from 11 genera was susceptible to KR1-1. Susceptible plants from the tribes Trifolieae, Cicereae, and Vicieae generally supported profuse urediniospore production, whereas susceptible species in the tribes Genisteae, Galegeae, and Hedysareae supported sparse urediniospore production. No susceptible species were found in the tribes Coronilleae or Loteae. The distribution of degree of susceptibility followed the current proposed phylogenetic relationships of these tribes. These results indicated that an isolate of U. striatus, found as a parasite of alfalfa, is capable of surviving and reproducing on a broad range of plant species. Parasitic efficiency was decreased with increased phylogenetic distance of the host species from alfalfa. The extent of the host range probably is a significant factor in the epidemiology of this alfalfa pathogen

The fungus-inoculated leaflets of 55 Trifolium species have been examined for the presence of isoflavonoid and non-flavonoid phytoalexins. Isoflavonoid derivatives belonging to the pterocarpan (medicarpin, maackiain and 4-methoxymaackiain) and isoflavan (vestitol, isovestitol, sativan, isosativan and arvensan) classes were isolated from 50 species whilst T. campestre and T. dubium accumulated the trihydroxy stilbene, transresveratrol. Three other species ( T. badium, T. scutatum and T. spadiceum ) apparently did not produce phytoalexins in response to fungal inoculation. The distribution and biosynthetic relationship of Trifolium phytoalexins is discussed and the genus compared with others belonging to the Trifolieae and related tribes.

Using the drop-diffusate technique, a number of isoflavonoid phytoalexins have been obtained from the excised, fungus-inoculated leaflets of 41 species belonging to the legume genus Trigonella . Leaf diffusates variously contained pterocarpan (medicarpin and maackiain) and isoflavan (vestitol and sativan) derivatives previously associated with genera closely allied to Trigonella . In diffusates from T. calliceras , medicarpin was accompanied by a phytoalexin (designated TC-1) provisionally identified as a new hydroxylated pterocarpan. Most of the Trigonella species were also examined for their ability to release coumarin upon tissue maceration. The combined phytoalexin/coumarin data suggest that three major intrageneric chemical divisions occur in Trigonella ; two of these apparently link the genus to Medicado/Factorovskya and Melilotus respectively, whilst the third provides some evidence for a connection with Trifolium . The taxonomic aspects of these findings are discussed in the light of earlier morphological studies which provided evidence for a distinct floral dichotomy amongst Trigonella species.

The genus Cicer has traditionally been placed in the Vicieae, although it has a number of morphological characters which suggest that it is out of place in that tribe and that its affinities lie elsewhere. A survey of pollen morphology in Cicer, the other genera of the Vicieae, the Trifolieae and the Ononideae has been carried out to help determine the relationships of Cicer. The tribe Vicieae (without Cicer) is very homogeneous and is characterized by its long, rectangular pollen grains with small, heavily thickened endoapertures. The Trifolieae is more variable in its pollen morphology but, in general, has rather similar grains to the Vicieae although the structure of the endoaperture is different. The Ononideae and Cicer have nearly spheroidal pollen with very large, unthickened endoapertures. It therefore appears that as far as pollen characters are concerned, Cicer does not belong in the Vicieae but has much more in common with the Ononideae.

Relative pollen and ovule production in the genera of the legume tribeTrifolieae is explored particularly as to howMedicago with its explosive pollination mechanism compares with its allies.Medicago produces much larger, although much fewer pollen per ovule than the other five genera in the tribe; this is interpreted as a consequence of its highly specialized, irreversible pollination mechanism, which allows only one effective exchange of pollen with pollinators.Melilotus andTrifolium produce a comparatively large quantity of pollen; this can be related to their floral characteristics requiring abundant pollen to achieve fertilization. InMedicago andTrigonella, annuals convert a higher proportion of pollen grains and ovules into seeds than perennials.

Detached leaves of 25 annual and perennial Medicago species have been inoculated with the fungus, Helminthosporium carbonum , and examined for subsequent production of isoflavonoid phytoalexins. Hydroxylated pterocarpan (medicarpin) and isoflavan (vestitol, sativan and isosativan) phytoalexins were obtained from most of the species investigated. Although large quantities of two flavonoid derivatives, isoliquiritigenin and liquiritigenin, were isolated from leaves of M. lupulina , this species was apparently unable to produce isoflavonoid compounds. Traces of 7-hydroxy-2′,4′-dimethoxyisoflavanone (a substance not previously recorded in the tribe Trifolieae) were obtained (together with medicarpin, vestitol and sativan) from M. sativa cv Du Puits. Some taxonomic aspects of phytoalexin induction are discussed with reference to the generic location of certain controversial Medicago species including M. (Trigonella ) radiata.

Numerical taxonomic studies were conducted on 164 species, including all of Medicago and Melilotus and most of Trigonella, the three genera of subtribe Trigonellinae, in order to clarify generic circumscription. The suite of 54 traditionally employed characters studied proved to be polythetic for all groupings of interest, i.e., no subset of individually fully discriminating characters was present, although the suite could be used collectively for discrimination. Medicago proved to be quite distinctive from Melilotus, but not from Trigonella. It was recently found that 51 species traditionally placed in Medicago and 32 species commonly excluded from this genus (and often placed in Trigonella) shared without exception a number of chemical, floral and seed characters, not studied here. That is, all of these 83 species can be assigned to Medicago, which is accordingly defined monothetically. In the present study it was found that characters used traditionally to circumscribe Medicago (with 51 species) by general morphological trends (i.e., polythetically) can also be used, although somewhat less effectively, to circumscribe Medicago in the broad sense (with 83 species). Therefore, prior to the recent discovery of characters that define Medicago monothetically, this genus was defineable only by general morphological trends, and these trends favored the narrower circumscription rather than the broader one now known to be justified. Variation between Trigonella and Melilotus also proved to be gradualistic for the characters studied. Unlike the Medicago–Trigonella problem, however, there are presently no known sets of individually diagnostic characters by which the continuum of variation should be split. These two genera are (arbitrarily) distinguishable as presently circumscribed, only tradition preventing the adoption of alternative, equally defensible ways of segregating them, or indeed of combining them. The study of Trigonella produced groupings essentially identical to the 12 sections of the classical monographer, Sirjaev, and clarified the relationships of several species. The study of Melilotus separated annuals and perennials, corresponding to the subgenera of the classical treatment of Schulz, but failed to reflect his sectional taxonomy. Melilotus bicolor is much closer to what is presently conceived of as Trigonella than to Melilotus.

Examination by scanning electron and light microscopy was carried out on all genera of the legume tribe Trifolieae (Medicago, Trigonella, Factorovskya, Melilotus, Trifolium, Ononis including Passaea, and Parochetus) and on some genera of tribe Loteae (Lotus, Tetragonolobus, and Dorycnium) which have been alleged to be closely related to the former assemblage. It was found that the stigmas of Medicago, including those of problematical species often placed in other genera, were fungiliform, with a basal circumferential ring of papillae and an apex apparently free of papillar outgrowths. The monotypic genus Factorovskya, a segregate from Trigonella, possesses a stigma substantially like that of Medicago. Moreover", several of the sections of Trigonella have stigmas like that of Medicago and quite unlike those of the bulk of Trigonella species. Medicago, Factorovskya, and these sections of Trigonella appear to form a distinct phylad, separable on the basis of stigma features from all of the other genera examined.

Published descriptions of suspensors from Mimosoideae (12 genera, 21 species), Caesalpinioideae (7 genera, 9 species), and Papilionoideae (about 65 genera, 150 species) were collated and compared with the most recent classification scheme of the Leguminosae. The first two subfamilies have mostly suspensorless embryos. Suspensors of various forms are usually present in the Papilionoideae (20 of the 32 tribes have been sampled). The putatively primitive and intermediately placed tribes have mostly inconspicuous suspensors. This is also true in some advanced tribes, but some or all members of other tribes have conspicuous suspensors of differing morphology: Phaseoleae, Loteae/Coronilleae, Vicieae/Cicereae/ Trifolieae, Crotalarieae, and Genisteae. There is no discernible correlation between suspensor development with amount of endosperm produced or amount present at maturity, or with habit, although elaborate suspensors are more common in derived herbaceous groups. Suspensor morphology helps to outline broad evolutionary trends in the family and to place studies on individual species in perspective.

Gland-tipped trichomes were found to occur on the cotyledonary petioles of a number of species of Medicago, Trigonella and Melilotus. Their location, seemingly protecting the plumule, and the known insect resistance provided by glandular hairs on stems and fruits of Medicago suggest that they are defensive, and may be useful in plant breeding.Key words: Medicago, alfalfa, Trigonella, Melilotus, glandular trichomes, pest resistance (immunity)

An antiserum specific for the legumin and vicilin of Vicia faba was used to examine extracts of seeds of taxa of the Fabeae and Trifolieae for the presence of related storage proteins, Proteins related to legumin were found to be widely distributed, indicating considerable conservation of the genetic information for this protein. Only Pisum sativum contained a protein immunochemically identical with the vicilin of V. faba; the equivalent proteins of all other genera tested here were immunochemically different from vicilin.

Medicarpin and maackiain have been obtained as phytoalexins from the fungus-inoculated stems of 15 Cicer species. These compounds co-occur with the constitutive isoflavones, formononetin and biochanin A. In the stem tissues of C. cuneatum , formononetin and biochanin A are accompanied by small quantities of a third constitutive isoflavone identified as 7-hydroxy-2′-methoxy-4′,5′-methylenedioxyisoflavone (cuneatin) by comparison with synthetic material. The taxonomic relationships between Cicer and genera of the tribes Trifolieae and Vicieae are briefly discussed.

The genus Sitona Germar is associated with papilionoid legumes of the tribe Trifolieae, and Medicago spp. in particular. The larvae eat root nodules, and the adults eat the foliage. In 1975, populations of S. discoideus Gyllenhal were found in Hawke’s Bay and Canterbury. Since then they have spread through the lucerne-growing areas of New Zealand, and are often found in high densities. This study was initiated in 1976 to provide basic information (for integrated control procedures) should this species ever become a pest in New Zealand. Adult S. discoideus feeds on M. sativa L. (lucerne), annual medicks (e.g., M. polymorpha L. and M. lupulinus L.), and Trifolium striatum L. The morphometric and gravimetric characteristics of all stages are recorded. These data are extended to show that 1000 completed larval developments/m2 remove 5.7 kg N ha-1 per generation from their host crop. Larvae spend 90% of their development period in nodules. Data were collected after carrying out general observations an...

Homoglutathione (hGSH: γ-glutamyl-eysteinyl-β-alanine) was purified from seeds of Phaseolus coccineus L. cv. Preisgewinner, using anion-exchange chromatography and Cu2O precipitation. Quantitative and specific determination of this thiol is possible by high-performance liquid chromatography (HPLC) after monobromobimane derivatization. The enzymatic recycling assay based on yeast glutathione reductase (EC 1.6.4.2) can also be applied, but only to samples containing either hGSH or glutathione (GSH), since enzyme reaction with hGSH is 2.7 times faster than with GSH. Using the very sensitive HPLC method, the thiol content of leaves, roots and seeds of several legumes was investigated. Although GSH and hGSH were found in all plants analysed, the GSH/hGSH ratio varied greatly within the different tribes as well as within the different organs of plants of one species. In seeds and leaves of Vicieae, only traces of hGSH were found beside the main thiol GSH, whereas in roots the hGSH content exceeded the GSH content. The Trifolieae contained both tripeptides and in the tribe Phaseoleae, hGSH predominated by far.

Trichomes of 39 species of Trifolieae belonging to six genera have been worked out. On the basis of structure they are classified into nine types and ontogeny of only four types could be studied. The structure and organographic distribution of each type has been described. All types of trichomes have been initiated from single initial cell.

Summary The globulins extracted from a number of different species of legume seeds have been subjected to disc electrophoresis. In the limited sample surveyed, the tribes Vicieae, Phaseoleae, Diocleae, Trifolieae and Daibergieae were each characterized by a distinctive protein band pattern. When the globulins of genera from the Loteae, Galacteae and Glycineae were examined, two types of protein band patterns were obtained which were distinctive for each tribe. A wider range of protein band patterns were obtained when genera of the Cajaneae were examined. The one species of Abrus examined possessed a globulin protein band pattern which differed from the patterns found in any other genera of the tribes examined. If the findings reported here can be extended to a much greater range of genera without significant change, then for some tribes within the Leguminosae a distinctive protein band pattern can be obtained when their seed globulins are electrophorized.

Summary The albumins extracted from the seeds of a number of different species of the Fabaceae have been subjected to disc electrophoresis on acrylamide gel. Both formic and glutamic dehydrogenase activities were readily detectable on the gels for ninety of the 103 species examined and one or other of the dehydrogenases on gels of the remaining species. The mobility values of the dehydrogenases varied among the different taxa examined. The more morphologically homogeneous the taxon the less variable were the enzymic data of the species within it, thus within the Vicieae, Trifolieae, Loteae and tribal groupings of Bentham's Phaseoleae species had more nearly similar formic dehydrogenase mobilities than did species of the Podalyrieae and Genisteae (sensu lato). Before any taxonomic conclusions can be drawn a much more extensive survey is necessary; however, sufficient correlations were observed between formic dehydrogenase mobilities and the globulin data of the previous paper to indicate the potential usefulness of this method in systematic studies.

Both Bentham and Hooker, and Taubert, admit that these characters do not absolutely distinguish the genera of this subtribe from all other genera of Fabaceae, for I-seeded indehiscent pods are found elsewhere in the family and glandular-dotted plants are also found, as Glycyrrhiza. They have, however, overlooked the fact that several of the species by them included in Psoralea have dehiscent pods. This is the case with all those segregated by me as the genus Pediomelum. I also suspect that in the genus Hoita, judging from the texture and structure, the pod also is tardily dehiscent. If so it is valvate, not circumscissile as in Pediomelum. Though there remains not a single character that absolutely distinguishes the genera of this tribe from all others in the family, the group is rather natural and in my opinion it should be regarded as a tribe rather than a subtribe of Galegeae. It shows, for instance, just as much affinity to Hedysareae or Trifolieae, in which tribes I-seeded indehiscent pods are found. In Cullen (a segregate from Psoralea), the leaflets are toothed and the pod much like that found in the latter tribe, while in Asphalthium the pod is practically a loment of 2 internodes, the lower closely investing the seed and the upper (the beak) empty and breaking off. The tribe shows many variations, and the genera show more abnormalities than in any other tribe as far as I know. The tribe includes herbs, shrubs, and trees, usually with gland-dotted foliage. In some cases the gland-dots are confined to the calyx or fruit alone. In one case, Or

From the n -hexane extract of the whole aerial part of flowering Ononis natrix , besides homopterocarpin and some known terpenoids and sterols, three new compounds: 8-hydroxy-6-methoxy-3-undecyl-3,4-dihydroisocoumarin, 5-(2-acetoxytridecyl)-3-methoxyphenol and 5-(2-hydroxytridecyl)-3-methoxyphenol have been isolated.

The subject of this note is a fragmentary collection on a herbarium sheet at W bearing the following information: "K. H. Rechinger 27934B, 15.4.1965, W. Pakistan, Baluchistan: Makran: Ras Nuh prope Gwadar, 25009'N, 62021'E, 50-150 m". This was annotated "Medicago n. sp." by S. I. Ali in 1971. Heyn (1984) described the new species M. makranica on the basis of this material. On further consideration, it has become evident that the collection is not related to tribe Trifolieae, as indicated by the following characteristics, which have never been found in the tribe: mature leaves bifoliolate, leaves with pulvini (in addition to the pulvinules of the leaflets), hairs biramous, and vexillum abaxially pubescent. Given this very distinctive assemblage of characters, as well as others of the collection, we have identified it as Indigofera nephrocarpa Balf. f. recognized by Balfour (1882; note Gillett's (1958) segregate, I. nephrocarpoides). This species of Pakistan, Oman, and the island of Socotra is included in Ali (1977) and Rechinger (1984). Duplicate herbarium sheets of the identical collection (Rechinger 27934B) are cited under I. nephrocarpa in these works, and in the latter, where the name M. makranica was coined, the same collection is thus listed for two "species"! The sheet of Rechinger 27934B at KUH and the second (additional to the holotype) sheet of this collection at W are accordingly isotypes of M. makranica Heyn. Rechinger 27934B and another collection from the same site (Jennifer Lamond 486, at K, cited by Ali, 1977) are the only recorded collections of I. nephrocarpa from Pakistan. Balfour (1888) stated that I. nephrocarpa of Socotra developed compact, tufted, depressed plants on the harder, limestone plains, but much more luxuriant plants under more favorable conditions. Ali (1977) recorded the information from Lamond 486, that is for the locus classicus of Medicago makranica Heyn, that the collection site was a "rocky top of cliff promontory"; this environment is consistent with the compact, depressed appearance of the holotype. Figure 1 illustrates characteristics of the collection more accurately than shown previously (Tab. 159, Heyn, 1984). The mature leaves of the holotype are all bifoliolate, not trifoliolate as in Medicago. (Indigofera nephrocarpa develops unifoliolate, conjugate, and trifoliolate leaves. Balfour (1882, 1888) noted that the trifoliolate leaves have alternate leaflets, not as in Medicago with a basal pair of opposite leaflets.) The fruit does not tend to coil, but consistent with the specific epithet, nephrocarpa, is reniform (however, coiling of the style may give the fruit an appearance reminiscent of that of Medicago lupulina L.). The calyx is not bilabiate, but rather the lobes are subequal. Flower structure was not previously studied, as very little floral material is present, and only a flower bud was available for analysis. A study of this bud showed that the nine stamens of the staminal column were arranged in a group of five with relatively large, dorsifixed anthers on short filaments, and an alternating group of four with somewhat smaller basifixed anthers on longer filaments (Fig. 1). This feature has apparently not been recorded for I. nephrocarpa, and its assumed absence by certain keys (e.g., in Rechinger, 1984) prevents identification. However, we emphasize that the observations are of a flower bud, and the differences between the stamens are obscure at maturity (see Tab. 18A, Balfour, 1888).

The analyses of immunological reactions obtained from extracts of seed storage proteins have provided a substantial contribution to our understanding of the systematics and classifications of the Leguminosae. The Mimosoideae subfamily is rather isolated, while the two other subfamilies, Caesalpinioideae and Faboideae are more closely related to each other. Within the subfamily Faboideae, Phaseolus and Vigna are extremely isolated from all other genera, these two genera are also isolated from all members of the family Leguminosae tested. The tribes Robinieae, Abreae, Aeschynomeneae, and Amorpheae constitute a natural group with about equal similarity to each other, and as a cluster they are distant from all other groupings tested. Galegeae, Vicieae, and Trifolieae were determined to be a homogeneous group of tribes based upon immunological similarity. The correct position of the tribe Loteae in respect to the above three tribes was not possible to ascertain. The Loteae seem to be partially related to the Bossiaeeae and Crotalarieae. Sophoreae, Thermopsideae, and Genisteae form a strong coherent group with high similarity detected between the three tribes. The serological data verify most aspects of the recent systems of classification of the Leguminosae, and indicate various questionable taxa and groupings (genera and/or tribes) requiring additional data to clarify proper relationships.

The genus Cicer, earlier classified in the tribe Vicieae of the legume family, along with vetches, lentils, and faba beans, is now classified in its own tribe, the Cicereae Alef.. Kupicha (1977) found that pollen morphology and vascular anatomy set Cicer species further apart from the other members of Vicieae (Lathyrus, Lens, Vicia, Pisum, and Vavilovia) and closer to the tribe Trifolieae, which differs from the Cicereae only in having hypogeal germination, tendrils, stipules free from the petiole and nonpapillate unicellular hairs.

Publisher Summary Galactomannans are reserve carbohydrates found in the endosperm cell walls of some legume seeds. They consist of a (1→4)-linked β-Dmannan backbone to which is attached single α-D-galactosyl residues at 0-6 of some of the D-mannosyl residues. The extent of D-galactosyl substitution of the D-mannan backbone varies from 0 to 10% in the “mannans” from palm seeds to almost complete substitution in the polymers from seed of some of the Trifolieae. The average ratio of D-galactose to D-mannose and the pattern of distribution of the D-galactosyl groups along the mannan backbone appear to be species specific. These parameters also dictate the ease of dissolution of the polysaccharide and the degree of self-association and the extent of synergestic interaction with agarose, xanthan, and K-carrageenan. This chapter describes the procedures for the quantitative extraction of hot and cold water-soluble fractions of carob galactomannan and of guar galactomannan. The chapter presents information on the fine structure and the solution properties.

In the common bean, Phaseolus vulgaris, two loci encode cytosolic glucosephosphate isomerase (GPI) subunits, whereas in the garden pea, Pisum sativum, only one locus is expressed. As a working model, we proposed that this change in isozyme number was produced by a gene-duplication event in the lineage leading to Phaseolus after divergence from that leading to Pisum. This model was tested by analyzing the GPI phenotypes in 119 legume genera, representing all three subfamilies and 23 of the 30 tribes of the Papilionoideae. The duplication was detected in 13 of the 20 papilionoid tribes surveyed, including several members of the putatively primitive tribe Sophoreae. Thus, the duplication appears to be an ancient event, a finding incompatible with the initial hypothesis. Instead, gene silencing is postulated to account for the absence of the duplicated phenotype in many tribes, including such advanced groups as Vicieae, Trifolieae, and Cicereae. Furthermore, silencing has occurred numerous times at lower taxonomic levels, including the subtribe Phaseolinae (Phaseoleae), a monophyletic group in which ten genera were found to have duplicated phenotypes and only one (Strophostyles) appeared to have an unduplicated phenotype. Analysis of GPI phenotypes also revealed numerous cases of partial silencing of duplicate loci as well as nearly equal expression of both loci in many, taxonomically widely scattered species. If our revised hypothesis is correct, this latter result implies that most of the subtribes had formed before significant divergence between the GPI isozymes occurred and, thus, that the radiation of the Papilionoideae was rapid relative to the rate of gene silencing.

Rhizobia are symbiotic bacteria that synthesize lipochitooligosaccharide Nod factors (NFs), which act as signal molecules in the nodulation of specific legume hosts. Based on the structure of their N-acyl chain, NFs can be classified into two categories: (i) those that are acylated with fatty acids from the general lipid metabolism; and (ii) those (= alphaU-NFs) that are acylated by specific alpha,beta-unsaturated fatty acids (containing carbonyl-conjugated unsaturation(s)). Previous work has described how rhizobia that nodulate legumes of the Trifolieae and Vicieae tribes produce alphaU-NFs. Here, we have studied the structure of NFs from two rhizobial species that nodulate important genera of the Galegeae tribe, related to Trifolieae and Vicieae. Three strains of Mesorhizobium huakuii, symbionts of Astragalus sinicus, produced as major NFs, pentameric lipochitooligosaccharides O-sulphated and partially N-glycolylated at the reducing end and N-acylated, at the non-reducing end, by a C18:4 fatty acid. Two strains of Rhizobium galegae, symbionts of Galega sp., produced as major NFs, tetrameric O-carbamoylated NFs that could be O-acetylated on the glucosamine residue next to the non-reducing terminal glucosamine and were N-acylated by C18 and C20 alpha,beta-unsaturated fatty acids. These results suggest that legumes nodulated by rhizobia synthesizing alphaU-NFs constitute a phylogenetic cluster in the Galegoid phylum.

Bacterial strains isolated from the nodules, tissues, and root surface of wild legumes growing in the Southern Urals related to the tribes Galegeae, Hedysareae, Genisteae, Trifolieae, and Loteae were examined for the presence in their genomes of symbiotic (sym) genes. It was found that the sym-genes are present in microorganisms isolated only from the nodules of the analyzed plants (sym+ -strains). Phylogenetic analysis of sym+ -strains on the basis of a comparative analysis of 16S rRNA gene sequences showed that sym+ -strains belong to five families of nodule bacteria: Mesorhizobium, Bradyrhizobium, Sinorhizobium, Rhizobium, and Phyllobacterium. A study the phylogeny of the sym-genes showed that the nodule bacteria of leguminous plants of the Southern Urals at the genus level are mainly characterized by a parallel evolution of symbiotic genes and the 16S rRNA gene. Thus, cases of horizontal transfer of sym genes, which sometimes leads to the formation of certain types of atypical rhizobial strains ofleguminous plants, are detected in nodule bacteria populations.

A total of 787 lines or ecotypes representing 179 species were tested for the presence or absence of tannins in their leaves using the vanillin/HCI spot test. Of the 11 3 species of Trifolium included in the survey, only five were found to contain tannins in their leaves and there was no evidence of tannin production in the 530 ecotypes of T. subterraneum tested. Our results, in agreement with previously published surveys, indicate that species with tannins in their leaves are very common in the tribe Hedysareae, less common in the tribe Loteae and rare in the other tribes of the Leguminosae, particularly the Trifolieae, which contains most of the important temperate pasture legumes. These findings are discussed in relation to the problem of developing, by interspecific hybridization or by induced mutation, low bloat risk pastures for temperate Australia.

The 19th century transfer of Cicer (Fabaceae) from the Vicieae to the monotypic Cicereae was recently reiterated by Kupicha. We present evidence to support this transfer based on seed morphology and testa topography as shown by scanning electron microscopy. Examination of 11 of the 40 species (a 28% sample) reveals five characteristics not found in most Vicieae seeds: 1) triangular to pyriform seed shape because of prominent beak bearing the hilum, 2) usually elaborate lens, 3) testa surface usually composed of large plates often conspicuously elevated to conical or spinose protuberances, 4) almost circular hilum with more or less con- spicuous hilar rim, 5) deltoid micropyle. Cicer microphyllum Benth. and C. montbretii Jaubert & Spach have an incpnspicuous lens and a papillose surface, suggesting a link with Vicieae. Cicer L. contains 40 species of annual or perennial herbs or shrublets. The natural range of the genus extends from Central Asia and the Hi- malayas to the eastern Mediterranean and Turkey, with isolated occur- rences farther west in Greece, Crete, Ethiopia, and Morocco. The best known spedies is C. arietinum L., chickpea or garbanzo, one of the oldest and most widely grown pulses in the Middle and Far East and in Spanish- speaking countries. This species, evidently a cultigen, is not known to occur in nature (van der Maesen 1972). Cicer traditionally has been placed in the Vicieae (Hutchinson 1964; Gunn 1969; Clarke and Kupicha 1976) although Alefeld (1859) had recognized it as a tribe. Kupicha (1977, 1981) provided an impressive array of evidence that Cicer again should be segregated from Vicieae as the independent tribe Cicereae Alefeld. She concluded that Cicereae was intermediate between Vicieae and Trifolieae. Ramanujam (1976) briefly reviewed chromosome number data for Vicieae, Trifolieae, and Cicer, and on that basis concluded that Cicer does not fit in either tribe. We present here information from seed morphology and surface topogra- phy that supports tribal status for Cicer.

When impermeable legume seeds are made permeable to water by mechanical treatments that make strophioles conductive, it is not known whether the strophioles themselves must be acted on directly. To investigate this question the testas of individual seeds from the genera Medicago, Stylosanthes and Trifolium were either broken through completely by cutting, filing or piercing, or stressed by squeezing or striking, at sites remote from the strophioles. As determined by serial photography, 30-90 % of the previously impermeable seeds became conductive at the strophiole. These results indicate that the strophiole can become conductive without being acted on directly. They also suggest that the strophiole and general testa should be regarded as an integrated system in which both water-repellency and mechanical properties of the testa are important in the control of water absorption.

The structure of stomata and hairs and stornatal ontogeny are described in 12 species of the tribe Trifolieae. Stomata may be paracytic, anisocytic, diacytic, haplocytic, and of transitional forms between diacytic and paracytic types. The most frequent types are paracytic, anisocytic, anomocytic and haplocytic. In any one species the most frequent type varies with the organ, and the pattern throughout the plant is not the same in every species. In general anomocytic stomata are most frequent on both surfaces of leaflets, and paracytic on stems.and petioles. On this basis the members of this tribe seem to have some uniformity. The ontogeny of stomata with subsidiary cells is mesogenous or meso- perigenous, or rarely perigenous. Anomocytic stomata are perigenous. The number of subsidiary cells is increased by (i) wall formation in the subsidiary cells, (ii) neighbouring perigenes assuming the form of subsidiary cells, or (iii) both processes operating in the same stoma simultaneously. Abnormalities such as contiguous stomata, stomata with one guard cell, and arrested development of stomata are occasionally met with. Hairs may be glandular or eglandular ; both types are present in all organs, except in a few cases. Some uniformity in the members of the tribe is also observed in the structure of glandular and eglandular hairs.

The leaves of the Trifolieae are trifoliolate except for the first which usually is single (unifoliolate). Hereditary deviations from this pattern have recently been described by Bingham (1966).t He described Medicago 8ativa L. plants in which all leaves were unifoliolate, and others in which all leaves, including the first, were trifoliolate. This communication reports some observations on fenugreek, Trigonella foenum-graecum L., which bear on the physiological conditions favouring one or the other developmental pathway.

A type of ineffective nodulation is described in which the bacteroids in the nodule cells fail to mature, and in which the infected host cells accumulate watersoluble polysaccharide between protoplast and cell wall. Ineffectiveness of this kind is characteristic of nodules� on Trifolium ambiguum M. Bieb. produced by unadapted strains of bacteria, or produced by adapted strains on a small proportion of plants. It is also found when strains effective with T. ambiguum nodulate subterranean or white clover. The polysaccharide in the peripheries of infected cells is readily seen by phase-contrast observation, provided the sections are not hydrated after removal of wax, but it is not visible by ordinary staining procedures.