Biological diversity of Salix taxa in Cu,Pb and Zn phytoextraction from soil

The aim of the study was to estimate the efficiency of copper (Cu), lead (Pb) and zinc (Zn) phytoextraction by 145 Salix taxa cultivated in an area affected by industrial activity. Survivability and biomass of plants were also analyzed. The highest Cu, Pb and Zn content in shoots was 33.38 ± 2.91 (S. purpurea × viminalis 8), 24.64 ± 1.97 (S. fragilis 1) and 58.99 ± 4.30 (S. eriocephala 7) mg kg^?1 dry weight, respectively. In the case of unwashed leaves, the highest content of these metals was 135.06 ± 8.14 (S. purpurea 26), 67.98 ± 5.27 (S. purpurea 45) and 142.56 ± 12.69 (S. alba × triandra 2) mg kg^?1 dw, while in washed leaves it was 106.02 ± 11.12 (S. purpurea 45), 55.06 ± 5.75 (S. purpurea 45) and 122.87 ± 12.33 (S. alba × triandra 2) mg kg^?1 dw, respectively. The differences between the highest and lowest values for Cu, Pb and Zn were 545%, 20500% and 535% in shoots; 2692%, 2560% and 7500% in unwashed leaves; and 3286%, 2221% and 6950% in washed leaves, respectively. S. acutifolia was able to effectively accumulate all three metals jointly, producing shoots that were well developed in both length and diameter when compared with the other tested willows—an ability that would suggest its high suitability for practical application.     

Susceptibility of willow clones (Salix spp.) to herbivory by Phyllodecta vulgatissima (L.) and Galerucella lineola (Fab.) (Coleoptera, Chrysomelidae)

Levels of damage by mixed natural infestations of the leaf-feeding chrysomelid beetles, Phyllodecta vulgatissima (L.) (the blue willow beetle) and Galerucella lineola (Fab.) (the brown willow beetle), were determined in replicated field plots of 24 Salix clones at Long Ashton (Bristol, UK) during 1993–94. Over the same period, the host plant preferences of both chrysomelids were investigated in a standard multiple-choice laboratory procedure, where beetles were enclosed in Petri dishes with leaf discs cut from young pot-grown trees propagated from shoot cuttings taken from 20 of the 24 willow clones represented in the field study. The laboratory experiments indicated that P. vulgatissima and G. lineola had similar host plant preferences in the range of willows examined (r >0.85). In both field and laboratory, the least preferred Salix clones and hybrids were those of 5. eriocephala, followed by S. purpurea, S. burjatica, S. dasyclados and S. triandra. Clones of S. eriocephala and S. purpurea were frequently rejected altogether in laboratory tests. Most preferred were clones of S. viminalis and several hybrids of S. viminalis, S. aurita, S. caprea and S. cinerea. These results substantiate the reports that P. vulgatissima and G. lineola are deterred from feeding on willows which have relatively high concentrations of phenolic (salicylate) glucosides in the leaves. The least preferred willows, particularly S. eriocephala, S. purpurea and S. burjatica, could be of great potential value in plant breeding for resistance to these willow beetle pests.     

Biotransformation of hydroquinone to arbutin in plant <Emphasis Type="Italic">in vitro</Emphasis> cultures — preliminary results

Cells from Echinacea purpurea (L.) Moench. (Asteraceae), Exacum affine Balf. f. (Gentianaceae), Melittis melissophyllum L. (Lamiaceae), Ruta graveolens L. and Ruta graveolens ssp. divaricata (Tenore) Gams. (Rutaceae) agitating cultures perform a biotransformation reaction on exogenously supplied hydroquinone into its β-D-glucoside — arbutin, product with valuable medicinal and cosmetic properties. The maximum content of arbutin (determined by HPLC) in the biomass from investigated cultures is 4.01; 3.44; 1.79; 2.48 and 5.07 g/100 g d.w., respectively. Nothing but Ammi majus L. (Apiaceae) cultures contain trace amounts of the product. Arbutin is accumulated in cells; it is occasionally found in media only in vestigial amounts. In most of the investigated cultures the efficiency of the biotransformation process is about 60 %.     

Anthocyanins in Salix species: A new anthocyanin in salix purpurea bark

Cyanidin 3-glucoside and delphinidin 3-glucoside (minor component) occurred in the bark of Salix purpurea (29 cultivars examined), S. fragilis (3 cvs), S. americana (4 cvs), S. rubra (1 cv.), S. incana (1 cv.), S. aegyptica (1 cv.) and S. alba (3 cvs) and several hybrids. A previously unrecorded anthocyanin was also present in appreciable amounts in the bark of eleven S. purpurea cultivars, notably those with small leaves. In other large-leaved cultivars of S. purpurea (18) it occurred only in traces or was not detected with certainty. A trace was found in one purpurea hybrid, but it was not detected in four others. Small amounts of the new anthocyanin were also found in S. incana (1 cv.), S. fragilis cv. Basfordiana, S. americana cv. Cordata and one hybrid, but were absent from other cultivars of S. fragilis (2) and S. americana (2), and also from S. alba (3), S. aegyptica (1), S. daphnoides (1), S. rubra (1), S. triandra (1), S. viminalis (1) and three hybrids. The new anthocyanin is unique in containing fructose as well as glucose and is based upon a previously undescribed anthocyanidin, possibly dimeric in nature, which is provisionally named purpurinidin.     

Asymbiotic germination of ornamental <Emphasis Type="Italic">Vanda:</Emphasis> in vitro germination and development of three hybrids

The majority of potted flowering orchids sold in the United States are Phalaenopsis hybrids. However, demand for other genera will undoubtedly increase as consumers become accustomed to growing orchids in the home. The objective of this study was to compare the germination and development of three Vanda hybrids, a genus with mass market potential. Specifically, we evaluated whether hybrids with different pedigrees have significantly different culture requirements. After 12 weeks culture, differences in germination and development were found among the three hybrids screened. Generally, seeds of Vanda Motes Primrose × Ascocenda Tavivat (hybrid S014) showed higher germination (82.0–95.3%) than seeds of V. Paki × (V. tessellata × V. cristata; hybrid S005) or (V. Joan Warne × V. Paki) × V. Loke (hybrid S013) when cultured on Knudson C, half-strength Murashige & Skoog, or PhytoTechnology Orchid Seed Sowing Medium under three photoperiods (8/16 h, 12/12 h, 16/12 h; light/dark). Protocorms of S005 and S013 did not develop beyond Stage 3 (first leaf present) under any of the conditions tested, while S014 seeds cultured on PhytoTechnology Orchid Seed Sowing Medium developed to Stage 4 (one leaf and ≥1 roots present; 0.5–0.6%) and 5 (two leaves and ≥1 roots present; 2.7–5.6%) under all photoperiods tested. All hybrids appeared to undergo similar early development (Stages 0–3). Limited advanced development of Hybrids S005 and S013 may be due either to inadequate culture conditions or low vigor of these hybrids. These data indicate that commercial production of some Vanda hybrids may be limited by slow growth and development. Efforts to breed hybrids which germinate and develop rapidly may be required to improve the mass market potential of Vanda hybrids.     

Contribution to the occurrence and former distribution of Tephroseris palustris (Compositae) in the Central Europe

Tephroseris palustris (syn. Senecio palustris) is a circumboreal species with large distribution range. The European part of the recent distribution area extends southwards to central France, Germany, Poland, and Ukraine, while in Great Britain, Czech Republic, Hungary, Slovakia, and Romania, T. palustris has been treated as extinct species. The southern boundary of its distribution in Poland does not reach the Carpathian territory. Herbarium specimens, formerly collected in Czech Republic, were found, however, all Czech localities are extinct. No herbarium specimens confirming the old literature data from Slovakia, Hungary, and Romania have been found. Some herbarium specimens coming from this area, and declared as T. palustris (S. palustris), in fact, refer to Senecio paludosus L. Contrary to previous nomenclature review (Jeffrey & Chen 1984), the name Tephroseris palustris (L.) Rchb. seems to be correct (Reichenbach Fl. Saxon.: 146, 1842).     

Tissue culture of the alternate hosts of wheat,rye and oat rusts and their response to in vitro inoculation with the rust pathogens

Alternate host plants of cereal rust fungi are necessary for studying the rust sexual cycle and pathogenicity. These plants are usually difficult to propagate through cloning, while seed-propagated plants may have variable responses to the pathogen. To overcome these obstacles, tissue culture, under controlled and aseptic conditions, was utilized for clonal propagation and in vitro inoculation of the following species: Rhamnus palaestinus Boiss., the alternate host of oat (Avena spp.) crown rust (Puccinia coronata Corda); Thalictrum speciosissimum L., the alternate host of brown leaf rust of wheat (Puccinia recondita f. sp. tritici Eriks. & Henn.); and Lycopsis arvensis L., the alternate host of rye (Secala spp.) leaf rust (Puccinia recondita f. sp. recondita Rob. & Desm.). Shoot culture procedures for initial establishment and proliferation were developed for all three alternate host species. Shoot cultures were multiplied at rates ranging from 0.3 to 1.7 shoots/week. Successful infection following inoculation with teliospores of the corresponding rust fungi was obtained for R. palaestinus and T. speciosissimum but not for L. arvensis. The hardening and acclimatization efficiency of rooted T. speciosissimum and L. arvensis was of 80–90%. The propagation efficiency for R. palaestinus was not successful because of the low rate and poor quality of its rooting. It is concluded that the in vitro system might be used as an alternative method for inoculation and multiplication of alternate hosts of cereal rusts, although more experimentation is needed to define accurately the appropriate conditions for the proper infection response. This revised version was published online in June 2006 with corrections to the Cover Date.     

Thidiazuron-induced regeneration of <Emphasis Type="Italic">Echinacea purpurea</Emphasis> L.: Micropropagation in solid and liquid culture systems

The goals of this study were to investigate thidiazuron (TDZ)-induced morphogenesis of Echinacea purpurea L. and to assess the possibility of developing a liquid-based protocol for rapid micropropagation. Callus development and root organogenesis were observed on leaf explants cultured on media containing 2,4-dicholorophenoxyacetic acid or dicamba, but no plantlets were regenerated. Addition of TDZ to the culture medium as the sole growth regulator resulted in the production of regenerable callus cultures. The highest rate of regeneration was observed for explants cultured on medium with TDZ at 2.5 μM or higher. Tissue derived from 1.0 μM TDZ treatments was used to initiate liquid cultures. All liquid treatments produced a similar number of regenerants but significantly more healthy plants were obtained from cultures grown in the presence of 0.1 and 1.0 μM TDZ. This TDZ-based micropropagation system is the first liquid, large-scale propagation protocol developed for the mass production of E. purpurea plants.     

The Effect of Lr19-Translocation on in Vitro Androgenesis and Inheritance of Leaf-Rust Resistance in DH3 Lines and F2 Hybrids of Common Wheat

Leaf-rust resistance and androgenesis were studied in the anther cultures of Triticum aestivum L., which included Saratovskaya 29 cultivar, the isogenic line Ps29, and three F₁ hybrids (L503/S55, L504/S58, ATS7/L1063) with 7DS-7DL-7Ae#1L translocation of Lr19 gene (Lr19 translocation) from Agropyron elongatum (Host.) P.B. The Lr19 translocation was shown to affect the induction of embryogenesis and green plant regeneration. The frequencies of Lr19 translocation differed in F₂ hybrids obtained by traditional hybridization and in sets of DH₃ lines obtained in F₁ anther cultures derived from the same combinations of T. aestivum parental forms. The number of leaf-rust resistant genotypes tended to decrease. The frequency of Lr19 translocation in the set of DH₃ lines derived from F₁ L504/S58 was significantly lower than in other sets of DH₃ lines and F₂ hybrid populations.     

Typification of Pallas’ names in <Emphasis Type="Italic">Salix</Emphasis>

Summary  The original collections of Salix species described by Pallas are discussed. Eight names validated by Pallas and one by Nasarov are typified. The use of six currently accepted names, S. arbutifolia Pall., S. arctica Pall., S. berberifolia Pall., S. caspica Pall., S. divaricata Pall. and S. rhamnifolia Pall., is confirmed. Salix serotina Pall. retains its place as a synonym of S. viminalis L. Salix gmelinii Pall. is resurrected and proposed as the correct name for the taxon previously known as S. dasyclados Wimm. S. burjatica Nasarow and S. jacutica Nasarow, the old synonyms of S. dasyclados, therefore are now also synonyms of S. gmelinii. A new combination S. rosmarinifolia L. subsp. sibirica is proposed.     

Regeneration of Echinacea purpurea: Induction of root organogenesis from hypocotyl and cotyledon explants

An in vitro propagation system was developed for Echinacea purpureaL. (purple coneflower), a medicinal plant commonly used in the treatment of colds, flu and related ailments. Root organogenesis from Echinacea purpurea hypocotyl explants was effectively induced by indolebutyric acid. Indoleacetic acid was found to be less effective than indolebutyric acid while treatments with naphthaleneacetic acid were ineffective for induction of root organogenesis. The results of this study have established a micropropagation system for Echinacea purpurea that will provide axenic plant material for further investigations into medicinally active biochemicals and the mass production of high-quality Echinacea purpurea root tissues for the commercial market. This revised version was published online in June 2006 with corrections to the Cover Date.     

Genetic distance as a predictor of heterosis and hybrid performance within and between heterotic groups in sunflower

Heterosis is significant for seed yield and is one of the driving forces behind the hybrid seed industry in cultivated sunflower (Helianthus annuus L). Heterotic groups in sunflower, if any other than the female and male inbred-line groups exist, have not been well studied or described. The primary aims of this study were to assess the utility and validity of a series of proposed heterotic groups and estimate correlations between genetic distance, heterosis, and hybrid performance for seed yield in sunflower. Fortytwo female by male heterotic group (A × R) and 81 female by female heterotic group (A × B) single-cross hybrids were grown in Corvallis, Ore., and Casselton, N.D., in 1996 and 1997. Heterosis was significant for seed yield and plant height but not for seed oil concentration and days to flowering. Genetic distances were significantly correlated with hybrid seed yield when estimated from AFLP fingerprints (G _D) (r = 0.63 for A × R and 0.79 for A × B hybrids), but not from coancestries (G _C) (r = -0.02 for A × R and 0.54 for A × B hybrids). G _D (R ² = 0.4) was a poor predictor of hybrid seed yield. The proposed heterotic groups in sunflower seem to have utility, but do not seem to be as strongly differentiated as those in corn (Zea mays L.). The highest-yielding hybrids were from the B_C× R_B heterotic pattern; however, several B_C× B_C hybrids (within-group hybrids) were among the top-yielding hybrids. The outstanding performance of certain B_C× B_C hybrids casts some doubt on the validity of the B_C group. Substantial genetic diversity seems to be present within and between heterotic groups in sunflower. Received: 1 September 1998 / Accepted: 14 September 1999     

Morphometric and population genetic analyses elucidate the origin,evolutionary significance and conservation implications of Orchis × angusticruris (O. purpurea × O. simia), a hybrid orchid new to Britain

We report the first confirmed occurrence in Britain of Orchis × angusticruris Franch. ex Rouy, a hybrid between two closely related orchid species of anthropomorphic Orchis (O. purpurea Huds. × O. simia Lam.) that hybridize frequently in Continental Europe. Seven individual hybrids, most likely F1 plants representing a single interspecific pollination event, first flowered with both parents in May 2006 at a nature reserve in the Chiltern Hills near Goring, Oxfordshire. Univariate and multivariate morphometric analyses (43 characters plus 12 indices), internal transcribed spacer sequencing, plastid microsatellites and amplified fragment length polymorphism (AFLP) analyses together readily separate the parents and confirm that O. purpurea was the ovule parent and O. simia the pollen parent, presumably reflecting the greater frequency and/or later flowering period of the latter at the site. This study reinforces a more general observation that, in most orchids, the ovule parent contributes substantially more to the hybrid phenotype than does the pollen parent, perhaps reflecting cytoplasmic inheritance. In contrast, the hybrids are placed closer to O. simia than to O. purpurea in the AFLP tree. Apparently recent arrivals, the few O. purpurea plants at Goring contrast genetically with the two other small populations of this species known in the Chilterns, but rather are consistent with relatively uncommon Continental populations. This suggests that the plants may have been deliberately introduced at Goring by man, although transport from the Continent in high‐level air currents cannot be ruled out. The Goring population of O. simia is likely to have become genetically impoverished through (1) preferential removal of many relatively fit plants to herbaria in the 19^th century and/or (2) a catastrophic population crash in the first half of the 20^th century. However, both our re‐examination of herbarium specimens and our population genetic data indicate past hybridization among anthropomorphic Orchis species occurring naturally in the Chilterns. Thus, we tentatively recommend retention of the hybrid plants at Goring, despite their likely anthropogenic origin from Continental material and the partial viability of their pollen and seeds, which offers opportunities for future introgression. Although the Goring hybrids broadly resemble morphologically O. militaris, another anthropomorphic Orchis still found at two Chiltern localities, sufficient morphological and molecular differences were observed to strongly refute our initial hypothesis that O. militaris could have originated through hybridization between ancestors that resembled O. purpurea and O. simia. The comparatively complex genetic properties evident in both O. simia and O. purpurea merit further study. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 687–711.     

Fitness of natural willow hybrids in a pioneer mosaic hybrid zone

Hybrid fitness is an important parameter to predict the evolutionary consequences of a hybridization event and to characterize hybrid zones. We studied fitness parameters of F₁ and later‐generation hybrids between the lowland species Salix purpurea and the alpine S. helvetica that have recently emerged during colonization of an alpine glacier forefield. Fruit production (number of capsules per catkin and fruit set) did not differ between hybrids and parents, but the number of seeds per capsule of F₁ hybrids was slightly lower than that of later‐generation hybrids and of the parents. Germination rates and seedling growth were tested on three substrates (pH 4.5, 7.0, and 8.0). Germination rates of seeds collected from F₁ hybrids were lower on acid and neutral substrates, but equal at pH 8.0 compared to all other groups, while the seeds from later‐generation hybrids performed as well as the parents on all three substrates. In seedling growth, the colonizer S. purpurea performed better than all other taxa on all three substrates, while hybrids resembled the subalpine species S. helvetica. Results suggest that endogenous selection acts against F₁ hybrids, but favors fitter genotypes in later‐generation hybrids. Exogenous selection via soil pH appears to be weak during seedling establishment. The pioneer vegetation on the glacier forefield may offer sufficient niche space for hybrid seedlings. Owing to the relatively high fitness of the hybrids and the scattered distribution of hybrids and parental individuals on the glacier forefield, this hybrid zone can be assigned to a mosaic model, probably facilitating gene flow and introgression between the parental species. As establishment of the hybrid zone appears to be linked to a colonization process, we propose to call it a pioneer mosaic hybrid zone.     

Entre Ríos Seedeater (Sporophila zelichi): a species that never was

ABSTRACT Entre Ríos Seedeaters (Sporophila zelichi), also called Zelich's Seedeaters, White‐collared Seedeaters, and Narosky's Seedeaters, are one of the rarest birds in the Neotropics. However, doubts have been raised about the validity of this species. Therefore, I evaluated the systematic status of Entre Ríos Seedeaters based on analysis of previously unpublished vocal and habitat data. I tested four hypotheses regarding the systematic status of S. zelichi: Good Species Hypothesis (valid species), Hybridization Hypothesis (hybrid S. palustris×S. cinnamomea), Color Morph Hypothesis I (morph of S. cinnamomea), and Color Morph Hypothesis II (morph of S. palustris). The songs and preferred habitat of S. zelichi are indistinguishable from those of Marsh Seedeaters (S. palustris), and the songs of both forms have exhibited similar changes from the early 1990s to 2003–2007. In contrast, the songs and preferred habitat of Chestnut Seedeaters (S. cinnamomea) differ from those of S. zelichi. Therefore, the Good Species Hypothesis is rejected by vocalization and habitat data, the Hybrid Hypothesis is undermined by the absence of shared vocal characters and limited habitat overlap of the proposed parental forms S. cinnamomea/S. palustris, and Color Morph Hypothesis I is rejected by both song and habitat data. However, Color Morph Hypothesis II is supported by both song and habitat data. Thus, I propose that S. zelichi be considered a color morph of S. palustris.     

Conservation genetics and evolutionary history of Gleditsia caspica: Inferences from allozyme diversity in populations from Azerbaijan

Gleditsia caspica is an endemic treespecies found in the endangered lowlandHyrcanian forests near the Caspian Sea insoutheastern Azerbaijan and northwestern Iran. Phylogenetic analyses show that G.caspica is a derivative of G. japonica,a widely distributed species of eastern Asia. Using allozyme markers to investigate geneticdiversity within two populations fromAzerbaijan, we discovered that a populationfrom a protected nature reserve was composedlargely of first-generation hybrids betweenG. caspica and G. triacanthos,which is native to eastern North America but isplanted as an ornamental shade tree inAzerbaijan. Hybrids exhibited higher levels ofself-fertilization and lower seed productionthan either parental species. In the secondpopulation, composed of pure G. caspica,11 of 31 loci scored were polymorphic, theaverage number of alleles per locus was 1.39,and gene diversity was 0.105. All diversityestimates were substantially lower than thosewe obtained from a small sample of G.japonica from South Korea and than estimatesfrom more extensive samples of South KoreanG. japonica and North American G.triacanthos published by other workers. Weconclude that (i) in addition to ongoingthreats from habitat conversion andfragmentation, G. caspica may also bethreatened in Azerbaijan by hybridization withG. triacanthos; and (ii) low variabilityin G. caspica populations is most likelynot a consequence of recent habitat loss andreductions in population size, but insteadreflects a long history of range contractionand endemism following isolation from G.japonica during the Pliocene or Pleistocene.     

Response of <Emphasis Type="Italic">Camptotheca acuminata</Emphasis> calli stimulated by mechanical vibration

Plants in their natural environment are usually affected by mechanical stress because of their sessile growth habit. This work was aimed at determining the effects of mechanical vibration on the growth rate, physiological indexes, and secondary metabolite biosynthesis of Camptotheca acuminata calli. In this study, mechanical vibrations of 1–4 Hz in frequency were applied to stimulate the C. acuminata calli; we found that a mechanical vibration of moderate frequency (2 Hz) can clearly promote the growth rate and increase the soluble protein content and superoxide dismutase (SOD) activity. Under a mechanical vibration of a 2 Hz frequency, camptothecin (CPT), the main secondary metabolite produced by C. acuminata, was increased by about fourfold compared to the control group, In contrast, the increased accumulation disappears at higher frequencies. The optimal vibration time for obtaining the highest levels of biomass and CPT was 60 min. This study showed that there are neutral frequencies and optimal periods of mechanical vibration on C. acuminata calli.     

The past and present occurrence of <Emphasis Type="Italic">Elatine</Emphasis> and implications for palaeoenvironmental reconstructions

The past and present occurrence of Elatine hydropiper L. (eight-stamened waterwort), E. hexandra (Lapierre) DC. (six-stamened waterwort) and E. triandra Schkuhr (three-stamened waterwort) in the Netherlands is discussed. It has proved possible to distinguish the slightly curved seeds of E. hexandra and E. triandra in subfossil material on morphological grounds. E. hexandra is the most common species at present, but subfossil finds are confined to Late-glacial and Pre-boreal sediments of one lake in the Pleistocene area of the Netherlands. Living plants of E. triandra have only been found in the Netherlands in 1838–1839, but there are 17 records from five archaeological sites, all located in the western Dutch estuarine area. Several of these sites also yielded E. hydropiper, archaeobotanically the most common species. The occurrence of E. triandra and E. hydropiper in the Netherlands seems to have been favoured by high summer temperatures. The ecological amplitude of this combination of species gives firm clues for the reconstruction of the environment, which must have been a freshwater tidal area. Since this type of environment is strongly threatened on a worldwide scale, the presence of these species in the past may also provide interesting information for present nature development projects in the Dutch estuarine area.     

IDENTIFICATION OF THE ANCESTRY OF AN AMPHIPLOID VIOLA WITH THE AID OF PAPER CHROMATOGRAPHY

Stebbins , G. L., B. L. Harvey , E. L. Cox , J. N. Rutger , G. Jelencovic , and E. Yagil . (U. California, Davis.) Identification of the ancestry of an amphiploid Viola with the aid of paper chromatography. Amer. Jour. Bot. 50 (8): 830–839. Illus. 1963.—Comparison of chromatograms obtained from extracts of dried leaves of various entities of the Viola purpurea complex as well as of V. pedunculata revealed the following. In respect to unidentified compounds differentially soluble in a mixture of tertiary butanol and acetic acid, with 15% acetic acid as a second solvent, the constitution of the tetraploid species V. quercetorum could be obtained by combining those of the diploid entities V. purpurea purpurea and V. aurea mohavensis. In respect to certain morphological characteristics, chiefly leaf shape and pubescence, beard hairs on lateral petals, anther appendages, and shape and hairs on styles and stigmas, V. quercetorum is intermediate between V. p. purpurea and V. a. mohavenis. The geographic distribution of V. quercetorum is likewise intermediate between those of the other 2 entities. Consequently, the origin of V. quercetorum by amphiploidy from hybrids between V. purpurea purpurea and V. aurea mohavensis is supported by 3 different lines of evidence. A possible place and time for this origin are the central Coast Ranges of California during the Pleistocene pluvial epoch. In both morphological characteristics and the chemical compounds revealed by the chromatograms, V. pedunculata subspp. pedunculata and tenuifolia show similarities and differences from members of the V. purpurea complex which are of a different nature than are the similarities and differences between the various entities of the latter complex. Consequently, the relationships between V. purpurea and V. pedunculata are probably not associated with or complicated by recent introgression or amphiploidy, and the 2 species may be rather distantly related to each other.     

MEIOTIC CHROMOSOME BEHAVIOR IN SOME INTERGENERIC HYBRIDS OF THE VANDA ALLIANCE

Tanaka , R., and H. Kamemoto . (U. Hawaii, Honolulu.) Meiotic chromosome behavior in some intergeneric hybrids of the Vanda alliance. Amer. Jour. Bot. 48(7): 573–582. Illus. 1961.—Meiotic chromosome behavior of 11 groups of diploid intergeneric hybrids (2n=38) of the Vanda alliance was investigated. Vanda Miss Joaquim × Luisia teretifolia and Ascocentrum curvifolium × Vanda lamellata usually produced 19 bivalents at metaphase I, indicating good homology of the parental chromosomes. Vanda tricolor var. sanderae × Vandopsis lissochiloides, Vandopsis lissochiloides × Vanda sanderiana, Vandopsis lissochiloides × Vanda Tatzeri and Arachnis flos-aeris × Vandopsis lissochiloides showed fair homology of parental genomes with formation of 12–15 bivalents at metaphase I. Trichoglottis brachiata × Vanda sanderiana, Vanda tricolor var. purpurea × Phalaenopsis denevei, Vanda Tatzeri × Aerides lawrenceae, Renanthera monachica × Vanda luzonica, Renanthera storiei × Vanda Clara Shipman Fisher and Aerides lawrenceae × Saccolabium giganteum, formed an average of 2–7 bivalents, thereby indicating poor homology of parental genomes. The hybrids, Renanthera monachica × Phalaenopsis sanderiana and Arachnis hookeriana × Vanda suavis, lacked chromosome pairing. On the basis of chromosome affinity at meiosis, a cytotaxonomic scheme was developed for the several genera of the Vanda alliance studied. Cytotaxonomy, evolution and breeding behavior in the Vanda tribe were briefly discussed.