Mating system and stigmatic behaviour during flowering of Alpinia kwangsiensis (Zingiberaceae)

 Little is known about the breeding systems of tropical perennial ginger species. In this paper, we provide information about the breeding system of Alpinia kwangsiensis in Yunnan, Southwest China, specifically self-compatibility, mechanisms promoting outcrossing, and the visitation characteristics of pollinators. Populations of A. kwangsiensis have two specific phenotypes that differ in flowering behaviour: 1) “cataflexistyle” individuals in which the stigma is held erect above the dehiscent anther when anthesis begins in the morning and becomes decurved under the anther at noon and 2) “anaflexistyle” individuals in which the receptive stigma is decurved under the indehiscent anther first and moves into a reflexed superior position above the anther as it begins to shed pollen at mid-day. The stigmatic movements in the two floral phenotypes, which occur in a ratio of 1:1 in natural populations, are synchronous and correlate with the foraging behaviour of floral visitors; pollination is effected only between floral forms. Field experiments indicate that A. kwangsiensis is self-compatible and dependent upon insects for fertilization. This newly reported floral mechanism, which we have named “flexistyly,” adds to the repertoire of devices that have evolved in flowering plants to insure outcrossing. Received November 29, 2001 Accepted January 8, 2002     

Ribulose-1,5-bisphosphate carboxylase/oxygenase from thermophilic cyanobacterium Thermosynechococcus elongatus

Ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) can be divided into two branches: the “red-like type” of marine algae and the “green-like type” of cyanobacteria, green algae, and higher plants. We found that the “green-like type” rubisco from the thermophilic cyanobacterium Thermosynechococcus elongatus has an almost 2-fold higher specificity factor compared with rubiscos of mesophilic cyanobacteria, reaching the values of higher plants, and simultaneously revealing an improvement in enzyme thermostability. The difference in the activation energies at the transition stages between the oxygenase and carboxylase reactions for Thermosynechococcus elongatus rubisco is very close to that of Galdieria partita and significantly higher than that of spinach. This is the first characterization of a “green-like type” rubisco from thermophilic organism.     

Expression of phytoene synthase gene (Psy) is enhanced during fruit ripening of Cara Cara navel orange (Citrus sinensis Osbeck)

Citrus is an important fruit crop as regards accumulation of carotenoids. In plant carotenoid biosynthesis, phytoene synthase gene (Psy) plays a key role in catalyzing the head-to-head condensation of geranylgeranyl diphosphate molecules to produce colorless phytoene. In the present paper, we reported the phytoene contents determination and characterization of Psy during fruit ripening of “Washington” navel orange and its red-fleshed mutant “Cara Cara”. Results showed that phytoene was exclusively accumulated in peel and pulp of “Cara Cara”. Although phytoene was observed accumulating with fruit ripening of “Cara Cara”, the contents in pulp were 10 times higher than those in peel. The isolated two Psy cDNAs were both 1520 bp in full length, containing 436 deduced amino acid residues, with a different amino acid at 412th. Genomic hybridization results showed that one or two copies might be present in “Cara Cara” and “Washington” genomes. During “Cara Cara” and “Washington” fruit coloration, expression of Psy was observed to be up-regulated, as revealed by tissue specific profiles in the flavedo, albedo, segment membrane and juice sacs. However, Psy expression in albedo of “Cara Cara” was higher than that in “Washington”, as evidenced by phytoene accumulation in the peel.     

Validation of the <Emphasis Type="Italic">VRN-H2</Emphasis>/<Emphasis Type="Italic">VRN-H1</Emphasis> epistatic model in barley reveals that intron length variation in <Emphasis Type="Italic">VRN-H1</Emphasis> may account for a continuum of vernalization sensitivity

The epistatic interaction of alleles at the VRN-H1 and VRN-H2 loci determines vernalization sensitivity in barley. To validate the current molecular model for the two-locus epistasis, we crossed homozygous vernalization-insensitive plants harboring a predicted “winter type” allele at either VRN-H1 (Dicktoo) or VRN-H2 (Oregon Wolfe Barley Dominant), or at both VRN-H (Calicuchima-sib) loci and measured the flowering time of unvernalized F₂ progeny under long-day photoperiod. We assessed whether the spring growth habit of Calicuchima-sib is an exception to the two-locus epistatic model or contains novel “spring” alleles at VRN-H1 (HvBM5A) and/or VRN-H2 (ZCCT-H) by determining allele sequence variants at these loci and their effects relative to growth habit. We found that (a) progeny with predicted “winter type” alleles at both VRN-H1 and VRN-H2 alleles exhibited an extremely delayed flowering (i.e. vernalization-sensitive) phenotype in two out of the three F₂ populations, (b) sequence flanking the vernalization critical region of HvBM5A intron 1 likely influences degree of vernalization sensitivity, (c) a winter habit is retained when ZCCT-Ha has been deleted, and (d) the ZCCT-H genes have higher levels of allelic polymorphism than other winterhardiness regulatory genes. Our results validate the model explaining the epistatic interaction of VRN-H2 and VRN-H1 under long-day conditions, demonstrate recovery of vernalization-sensitive progeny from crosses of vernalization-insensitive genotypes, show that intron length variation in VRN-H1 may account for a continuum of vernalization sensitivity, and provide molecular markers that are accurate predictors of “winter vs spring type” alleles at the VRN-H loci.     

Chemotaxonomic studies onArachniodes (dryopteridaceae) III. Phloroglucinol derivatives of putative hybrids

Phenetic variation found in JapaneseArachniodes was compared with phloroglucinol composition. The differences in this chemotaxonomic feature were not found very useful in defining the taxa inArachniodes. The phloroglucinol compositions of the putative hybrids were determined and compared with those of the presumed parent species. It was concluded that, in general, the hybrids combine the phloroglucinols found in their parent species. Hybridization among the Japanese species ofArachniodes should, however, be confirmed by cytological investigations. Five species of Kalimantan (Bornean) ferns were also studied for their phloroglucinol contents.Arachniodes tripinnata was compared with Philippine materials of the same species with the result that they differed to some extent. In addition, four species belonging to Tectarioideae were examined:Heterogonium is devoid of phloroglucinols, andPleocnemia irregularis contains a great deal of a “yellow compound” of unknown structure.     

The expression of floral organ identity genes in contrasting water lily cultivars

The floral organs of typical eudicots such as Arabidopsis thaliana are arranged in four characteristic whorls, namely the sepal, petal, stamen and carpel, and the “ABC” floral organ identity model has been based on this arrangement. However, the floral organs in most basal angiosperms are spirally arranged with a gradual transition from the inside to outside, and an alternative model referred to as “fading borders” was developed to take account of this. The flower morphology of the water lily was tested against the “fading borders” model by determining the expression profile of the six primary floral organ identity genes AP2, AGL6, AP3, PI, AG and SEP1 in two cultivars showing contrasting floral morphology. In addition, to get accurate floatation of the genes expression level from outer to inner, we divided the floral organs into eight whorls according to morphological features. All these genes were expressed throughout all whorls of the flower, but their expression level changed gradually from the outside of the flower to its inside. This pattern was consistent with the “fading borders” model.     

A “Nonsterile” Method for Selecting and Growing <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> Transformants (T<Subscript>2</Subscript> Transgenic Lines) Resistant to Kanamycin

A breakthrough in transgenic Arabidopsis thaliana research was the development of the floral dip transformation protocol, a simple and reliable method of obtaining transformants, T₁ transgenic lines, at high efficiency while avoiding the use of tissue culture. However, the traditional protocol (a “sterile” method) of obtaining T₂ transgenic lines has not evolved along with improvements in transformation technology as it continues to be laborious and time-consuming. In this study, we report on the development of an improved protocol (a “nonsterile” method) for selecting and growing A. thaliana transformants (T₂ transgenic lines) resistant to kanamycin under nonsterile conditions. This protocol involves the use of a simple yet specialized device that will aid in solium selection of T₂ transgenic lines that can be rapidly grown in a hydroponic system. The “nonsterile” method reduces labor and time involved as compared to the “sterile” method; moreover, it is easy to set up and maintain. This method may also be applicable to other selecting agents, and perhaps to other plants.     

Floral and pollinator behaviour of flexistylous Bornean ginger, Alpinia nieuwenhuizii (Zingiberaceae)

Flexistyly is a unique floral mechanism involving extreme curving of the style. It was first described in Chinese ginger (Amomum, Zingiberaceae). This is a pioneer report on flexistylous gingers of Malesia, where most species of this family grow. We observed the floral behaviour and flower visitors in Alpinia nieuwenhuizii Val., a Bornean endemic. Although the floral behaviour and effective pollinators (carpenter bees, Xylocopa) were similar between the Bornean species and the previously reported flexistylous Alpinia, the pollinator behaviour between them strikingly differed with regard to the visit frequency of the pollinators showing a bimodal pattern during the day. This was a better match for the floral behaviour of the flexistylous Alpinia. Some gender differentiation observed between the two types of morphs is also discussed in the present study.     

Associations between floral specialization and species diversity: cause, effect, or correlation?

It has been proposed frequently, from Darwin’s time onwards, that specialized pollination increases speciation rates and thus the diversity of plant species (i.e. clade species richness). We suggest here that the correlation between clade species richness and floral specialization is real, but that clade species richness is frequently the cause, not the result of floral specialization. We urge a broader, variance-partitioning perspective for assessing the causes of this correlation by suggesting four models of how the diversity-specialization correlation might come about: (1) floral specialization promotes initial reproductive isolation (“Initial-RI” model), (2) floral specialization promotes reinforcement of reproductive isolation upon secondary contact (“Reinforcement” model), (3) floral specialization reduces the extinction rate by promoting tighter species packing (“Extinction” model), (4) floral specialization is the result of high clade species richness, which increases the number of related species in communities, and thus selects for floral character displacement (“Character-Displacement” model). These hypotheses are evaluated by comparing the relationships between species richness, speciation mechanisms, and pollination precision, accuracy, and specialization in the broader literature and, more specifically, in four study systems: Dalechampia (Euphorbiaceae), Collinsia (Plantaginaceae), Burmeistera (Campanulaceae), and Stylidium (Stylidiaceae). These systems provide stronger support for the character-displacement hypothesis, wherein local species diversity drives the evolution of specialized pollination. Although the two reproductive-isolation hypotheses may hold for plants like orchids, with extremely precise pollination systems, the reproductive character-displacement hypothesis seems likely to be more important for plant groups with less precise pollination systems.     

Development of SCAR markers linked to powdery mildew (<Emphasis Type="Italic">Uncinula necator</Emphasis>) resistance in grapevine (<Emphasis Type="Italic">Vitis vinifera</Emphasis> L. and <Emphasis Type="Italic">Vitis</Emphasis> sp.)

Sequence-characterized amplified regions markers (SCARs) were developed from six randomly amplified polymorphic DNA (RAPD) markers linked to the major QTL region for powdery mildew (Uncinula necator) resistance in a test population derived from the cross of grapevine cultivars “Regent” (resistant) × “Lemberger”(susceptible). RAPD products were cloned and sequenced. Primer pairs with at least 21 nucleotides primer length were designed. All pairs were tested in the F1 progeny of “Regent” × “Lemberger”. The SCAR primers resulted in the amplification of specific bands of expected sizes and were tested in additional genetic resources of resistant and susceptible germplasm. All SCAR primer pairs resulted in the amplification of specific fragments. Two of the SCAR markers named ScORA7-760 and ScORN3-R produced amplification products predominantly in resistant individuals and were found to correlate to disease resistance. ScORA7-760, in particular, is suitable for marker-assisted selection for powdery mildew resistance and to facilitate pyramiding powdery mildew resistance genes from various sources.     

Variation in stigma morphology – How does it contribute¶to pollination adaptation in Pedicularis (Orobanchaceae)?

 Stigma morphology in Pedicularis and its role in pollination have not been evaluated. This paper reports for the first time the relationship between stigma morphology and other aspects of floral design. 17 species of Pedicularis representing all the different types of corolla structure in the genus were studied in the field and in the laboratory. Results indicate that the stigmatic surface morphology of Pedicularis species is related to the type of corolla structure occurring in the species. Pollination studies in eight Pedicularis species demonstrated adaptation between stigmatic surface morphology and other aspects of floral biology. Species with larger, more corrugated stigmatic surfaces always possess a subsidiary construction (“tooth” or “beak”) on the galea. In addition, they have relatively longer flower tubes, higher stigmatic pollen loads, bigger pollen size and a shorter blooming period for individual flowers. Finally, the authors discuss the evolutionary significance of floral design in genus Pedicularis. Received April 8, 2002; accepted June 11, 2002 Published online: December 11, 2002     

Foliage consumption and larval development of parasitized and unparasitized soybean looper,Pseudoplusia includens [Lep.: Noctuidae], reared on a resistant soybean genotype and effects on an associated parasitoid,Compidosoma truncatellum [Hym.: Encyrtidae]

Field grown foliage from the resistant soybean [Glycine max (L.) Merrill] breeding line GAT “81–327” and the susceptible cultivar “Ransom” was used to rear unparasitized larvae of the soybean looper (SBL),Pseudoplusia includens (Walker), and larvae parasitized byCopidosoma truncatellum (Dalman). SBL larvae, whether parasitized or not, consumed more foliage when fed “Ransom”. Unparasitized larvae reared on “81–327” had longer developmental times and suffered greater mortality than unparasitized larvae reared on “Ransom”. Parasitization of SBL larvae byC. truncatellum increased total foliage consumption of both soybean lines. Parasitized larvae reared on the resistant “81–327” weighed less and yielded fewer parasitoid adults.

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Résumé Des larves dePseudoplusia includens (Walker) parasitées ou non parCopidosoma truncatellum (Dalman) ont été nourries des feuilles de deux lignées de soja [Glycine max (L.) Merrill] l'une, GAT “81–327” résistante et l'autre, “Ransom” sensible. Les larves deP. includens qu'elles soient parasitées ou non consommaient plus de feuillage lorsqu'elles étaient nourries de la lignée “Ransom”. Les larves non parasitées élevées sur “81–327” avaient un cycle de développement beaucoup plus long et un taux de mortalité beaucoup plus élevé que les larves non parasitées élevées comparativement sur feuilles de “Ransom”. Par contre, les larves parasitées manifestaient une consommation accrue du feuillage des deux lignées de soja. Les larves parasitées élevées sur les feuilles de la variété résistante GAT “81–327” pesaient moins et produisaient moins également de parasites adultes.

     

Traditional Knowledge and Management of <Emphasis Type="Italic">Feijoa (Acca sellowiana)</Emphasis> in Southern Brazil

Traditional Knowledge and Management of Feijoa (Acca sellowiana) in Southern Brazil. This paper investigates traditional knowledge of the use and management of Acca sellowiana in southern Brazil. Fifty-six informants from three rural communities were assigned to one of four subgroups (“maintainers,” “managers,” “cultivators,” or “users”) based on their responses regarding management and use of A. sellowiana. Traditional knowledge related to use of this species is widespread among rural residents, but traditional knowledge related to management is fragmented depending on whether one uses, manages, or cultivates the species. Knowledge held in rural communities suggests that A. sellowiana could play an expanded role in local economies as well as biodiversity conservation. We suggest that participatory research could stimulate greater local use as well as on-farm conservation of A. sellowiana.     

Observations on Flattened Species of Gracilaria (Gracilariaceae, Rhodophyta) from Taiwan

Four flattened Gracilaria species have been reported from Taiwan: G. spinulosa, G. vieillardii, G. textorii and G. punctata, identified based on branching pattern, the presence or absence of spines, and characters that often vary seasonally. Gracilaria spinulosa was originally described from the type locality, Tainan. Species with toothed margins are usually referred to G. “vieillardii”; those with smooth margins to G. “textorii”, and those with smooth margins and dark spots scattered over the blade to G. “punctata”. Molecular analyses show that specimens with marginal teeth cluster in three different groups: a G. “vieillardii” clade, a G. spinulosa clade, and a clade sister to G. spinulosa. An undescribed species comprises the third clade, which is distinguished by its relatively large gonimoblast cells and weakly developed tubular nutritive cells. The three clades can be separated by the character of the tubular nutritive cells, the size of gonimoblast cells and certain vegetative features. Plants with entire margins form a single clade characterized by cystocarps with basal tubular nutritive cells and their absence in the cystocarp cavity. They are nested in the Hydropuntia complex and are referred to as Gracilaria “punctata” here. The records of G. textorii and G. punctata from Taiwan require reinvestigation in comparison with the Japanese species.     

Systematics and genetic variation in commercial shape Kappaphycus and shape Eucheuma (Solieriaceae, Rhodophyta)

The systematics and taxonomy of Kappaphycus and Eucheuma (Solieriaceae) is confused and difficult due to morphological plasticity, lack of adequate characters to identify species and commercial names of convenience. These taxa are geographically widely dispersed through cultivation. Commercial, wild and herbarium sources were analysed; molecular markers provided insights into taxonomy and genetic variation, and where sources of genetic variation may be located. The mitochondrial cox2-3 and plastidal RuBisCo spacers were sequenced. There is a clear genetic distinction between K. alvarezii (“cottonii”) and K. striatum (“sacol”) samples. Kappaphycus alvarezii from Hawaii and some samples from Africa are also genetically distinct. Our data also show that all currently cultivated K. alvarezii from all over the world have a similar mitochondrial haplotype. Within Eucheuma denticulatum (“spinosum”) most African samples are again genetically distinct. Our data also suggest that currently cultivated E. denticulatum may have been “domesticated” several times, whereas this is not evident for the cultivated K. alvarezii. The present markers used do not distinguish all the morpho-types known in cultivation (e.g. var. tambalang, “giant” type) but do suggest that these markers may be useful to assess introductions and species identification in samples.     

The taxonomy of Vaccinium section Myrtillus (Ericaceae)

Phenetic analyses of 218 OTUs belonging toVaccinium sectionMyrtillus and scored for 13 characters generated five robust clusters.Vaccinium parvifolium is the most distinct cluster, followed by the “myrtillus-scoparium” complex, thenV. membranaceum, V. caespitosum, and the “ovalifolium-deliciosum” complex. Biosystematic studies suggest that the five clusters comprise seven taxa that possess many of the properties that define biological species. Indeed, the recognition of the seven taxa as species is supported by cytological, phenological, biogeographical and ecological as well as chemical data. A detailed taxonomic treatment for all these taxa is presented.     

<Emphasis Type="Italic">Mesopithecus</Emphasis> (Primates,Cercopithecidae) from the turolian locality of Vathylakkos 2 (Macedonia,Greece)

Two skulls, two mandibles and some postcranials ofMesopithecus from the locality “Vathylakkos 2” of Axios Valley (Macedonia, Greece) enlarge our knowledge about the genus and its differentiation. The new material together with an old skull from the same locality is compared with the Pikermi, “Ravin des Zouaves 5” (Axios Valley), and Maramena (Serres basin) samples. It is concluded that the VathylakkosMesopithecus resemblesM. pentelicus from Pikermi, as wellM. delsoni from “Ravin des Zouaves 5” and it is referred asMesopithecus sp. aff.M. pentelicus. The biochronological age of “Vathylakkos 2” has been considered as MN 12, while recent magnetostratigraphic data indicate an age of about 7.5 Ma. This age confirms the position of the VathylakkosMesopithecus between Pikermi and “Ravin des Zouaves 5”. Some dental indices compared with those of the RecentCercopithecus suggest that the Vathylakkos sample is monospecific.      

Variability and structure of natural populations of Elymus caninus (L.) L. and their possible relationship with Hordelymus europaeus (L.) Jess. ex Harz as revealed by AFLP analysis

The AFLP method was used to study the inter-population variability of eight populations of Elymus caninus (L.) L. as well as three populations of Hordelymus europaeus (L.) Jess. ex Harz. In these studies a clear distinction was found between two phenotypes of E. caninus collected in the same locality. It also appeared that two populations of E. caninus representing the “pauciflorum” morphotype were clustered together, similarly as two populations of E. caninus exhibiting morphotype “caninus”. Additionally, the populations of the “pauciflorum” type were clustered together with all samples of H. europaeus. Furthermore, the same approach was applied to analyze the intra-population variability of E. caninus. The populations ranged from nearly uniform to as diverse as the samples collected from different localities. In some populations of this species the presence of off-type plants was revealed. Our data indicate the predominantly self-pollinating character of E. caninus and the possible genetic relationship between of E. caninus and H. europaeus. It is the second paper from the series: Biodiversity of wild Triticeae (Poaceae) in Poland, the first is: Mizianty M. 2005. Variability and structure of natural populations of Elymus caninus (l.) L. based on morphology. Pl. Syst. Evol. 251: 199–216.     

Upper limits of temperature for growth inChlorella (Chlorophyceae)

The upper limit of temperature for growth is a species-specific character in the genusChlorella. The limits of 14Chlorella species range from 26–30°C (C. saccharophila) to 38–42°C (C. sorokiniana), withC. fusca var.vacuolata (34°C) andC. kessleri (34–36°C) assuming an intermediate position. Thus, there is no wide gap in the temperature limits between the normal (“low-temperature”) species ofChlorella and the “high-temperature” species,C. sorokiniana.     

Lagomorphs from the Miocene of Sandelzhausen (southern Germany)

Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.