Germination and development of the soma in Boschniakia hookeri (Orobanchaceae)

Germination of the holoparasitic angiosperm Boschniakia hookeri differs from the usual pattern among the Orobanchaceae. In most members of the family, the germinating seed develops a radix which establishes contact with the host root; in contrast, in B. hookeri the host root makes contact with the parasite seed, penetrates its testa, and association between host root and parasite embryo tissues is then established inside the testa.
The germination and development of the perennial vegetative body, the soma, can be divided into ten stages, with characteristic changes from stage to stage. The first four stages range from the pre–germination through the germination proper, including physical contact between parasite and host root; formation of the soma, through development of the first stem bud, occurs in stages five to ten. The processes for the first six stages occur completely within the testa.
The mature soma apparently produces flowers when it reaches a size around 15 mm in diameter and continues to grow. Maximum seems to be around 50–60 mm, where dense clusters of 10–12 inflorescences can occur.     

Parasites of fishes in the Colorado River and selected tributaries in Grand Canyon, Arizona

As part of the endangered humpback chub (HBC; Gila cypha ) Adaptive Management Program, a parasite survey was conducted from 28 June to 17 July 2006 in 8 tributaries and 7 adjacent sections of the main stem of the Colorado River, U.S.A. In total, 717 fish were caught, including 24 HBC. Field necropsies yielded 19 parasite species, 5 of which (Achtheres sp., Kathlaniidae gen. sp., Caryophyllaidae gen. sp., Myxidium sp., and Octomacrum sp.) are new records for Grand Canyon, Arizona, U.S.A. Spearman's correlation coefficient analyses showed no correlations between parasite burden and fork length for various combinations of fish and parasite species. Regression analyses suggest that no parasite species had a strong effect on fish length. The most diverse parasite community (n = 14) was at river kilometer (Rkm) 230, near the confluence of Kanab Creek. The most diverse parasite infracommunity (n = 12) was found in the non-native channel catfish (CCF; Ictaluris punctatus). Overall parasite prevalence was highest in CCF (85%) followed by that in HBC (58%). The parasite fauna of humpback chub was mainly composed of Bothriocephalus acheilognathi and Ornithodiplostomum sp. metacercariae.     

Gel electrophoresis studies of proteins from leaves of photoperiodically induced and vegetative cocklebur plants

Comparisons of proteins synthesized in photoperiodically-sensitiveleaves of induced and vegetative cocklebur plants were made.Fifteen or more protein bands could be separated by polyacrylamidegel electrophoresis when polyvinylpyrrolidone was used in theextracting buffer to remove phenolics. As contrasted to resultsof others with Pharbilis nil, no differences in stained bandingpatterns could be detected in vegetative and induced plants.Radioactive leucine, lysine and phenylalanine were incorporatedinto similar leaf proteins during the last half of an inductivedark period. These experiments and dual-labeling studies with³H- and ¹⁴C-phenylalanine indicated no consistent differencesin the types of extracted proteins synthesized by leaves ofvegetative and induced plants. ¹Present address: Plant Science Dept., Utah State University,Logan 84321, U.S.A. (Received October 26, 1970; )     

SOME EFFECTS OF KINETIN ON THE GROWTH AND FLOWERING OF INTACT GREEN PLANTS

Wittwer , S. H., and R. R. Dedolph . (Michigan State U., E. Lansing.) Some effects of kinotin on the growth and flowering of intact green plants. Amer. Jour. Bot. 50(4): 330–336. Illus. 1963.—Dry matter accumulation of aerial parts, and heights of tomato, cucumber, and pea plants were markedly reduced when kinetin was incorporated into the culture solution root medium in concentrations ranging from 10^–5 to 10^–7 M. Concentrations which suppressed top growth (height, dry weight) generally had lesser effects on root growth and, in some instances, enhanced it. Thus top/root ratios were greatly reduced and approached unity in kinetin-treated peas and tomatoes. Flowering was inhibited in tomatoes and accelerated in peas. There were marked changes in root morphology, including the formation of pseudonodules. Kinetin had an effect which was opposite to that of gibberellin on internode elongation, root extension, top/root ratios and flowering of dwarf peas. N⁶-benzyladenine was more active than kinetin in suppressing the growth of intact green plants. The data show that kinetin can markedly alter the behavior of intact plants when absorbed by the roots from culture solutions in which the concentrations are comparable to those which are biologically active on explants.     

Intraspecific differentiation of Pleurospermum hookeri (Apiaceae), and its interspecific relationships with two close relatives in the genus Pleurospermum

In order to clarify the interspecific relationships of a lineage in Pleurospermum, P. hookeri C. B. Clarke, P. yunnanense Franch., and P. giraldii Diels, and to understand intraspecific divergence of P. hookeri, a phylogeographic study was carried out based on 198 individuals from 24 populations. Three chloroplast DNA regions, ndhF-rpl32, trnL-trnF, and trnQ-rps16, were sequenced in the present study. The genetic relationship between P. hookeri and P. giraldii is not as close as previously assumed. Pleurospermum hookeri and P. giraldii may originate from an unknown ancestor located in the Qinling region. Pleurospermum yunnanensewas found to be the closest relative of P. hookeri in all the species included in the phylogenetic analysis. The two haplotypes identified from P. yunnanense are shared with P. hookeri, which is potentially a result of both incomplete linkage sorting and introgression. Three large divergences within P. hookeri were identified, located at the northeastern edge, southeastern edge, and platform of the Qinghai–Tibet Plateau (QTP), respectively. Long-term history can explain the deep intraspecific divergence of P. hookeri. The uplift of the QTP played a key role in that divergence, and then were the climatic changes in the Quaternary. In addition, we found one refugium at the northeastern edge of the QTP, one at the southeastern edge, and at least one in the Hengduan Mountains region on the platform of the QTP.     

PARTHENOGENESIS IN TETRAPLOID LILIUM LONGIFLORUM

Emsweller , S. L., and Joseph Uhring . (U.S.D.A., Beltsville, Md.) Parthenogenesis in tetraploid Lilium longiflorum. Amer. Jour. Bot. 49(9): 978–984. Illus. 1962.—Nine maternal polyhaploids from 1 capsule and 1 tetraploid from another were produced following pollination of 2 tetraploid Lilium longiflorum plants with pollen from diploids of the same species. One of the 9 plants had 25 chromosomes; the extra chromosome was identified as a modified D. Two other plants had 2 new chromosomes each and the remaining 6 had 24 unmodified chromosomes. Translocations in meiosis of the tetraploid produced the new chromosomes. One plant obtained from a second capsule had 48 chromosomes. The 9 plants were smaller than diploids and the 48-chromosome plant was considered a diploid until mitosis was observed. The 9 plants originated from unfertilized eggs of the tetraploid, and the 48-chromosome plant presumably from chromosome doubling of an egg cell.     

Haligena salina: a new marine pyrenomycete

EARRANT, C. A. & JONES, E. B. G., 1986. Haligena salina: a new marine pyrenomycete. Haligena salina sp. Nova (Ascomycotina, Sphaeriales, Halosphaeriaceae) collected on wood from San Juan Island, Washington State, U.S.A., and on reeds from Pisa, Italy is described. The species is compared with Haligena elaterophoraj. Kohlmeyer and species in the genus Remispora Linder.     

Vacuolar protein in apical and flower-petal cells

Summary Vegetative apices, floral apices and flower petals of five Solanaceae (potato, tomato, tobacco, petunia and nightshade) and of corn and Nigella were examined with an electron microscope for the presence of protein bodies in the cell vacuoles. Electron-dense bodies were found in vacuoles of all plants investigated but not in every tissue examined. The bodies observed in the apices are similar to the protein bodies previously found in tomato leaves where they appear to be related to the presence of chymotrypsin inhibitor I protein (Shumway et al., 1970). The bodies appeared in very young cells in small vacuoles, disappearing as the cell matured. They are apparently related to the growth and development of the new cells. The results suggest that plants may regulate specific proteins within the apical region through selective synthesis and degradation of proteins accompanied by compartmentalization in the vacuole.Scientific Paper No. 3822, College of Agriculture, Washington State University, Pullman, Project 1791. This investigation was supported in part by the State of Washington Initiative Measure 171 funds, the Graduate School Research funds, by the U.S. Department of Agriculture, Cooperative State Research Service Grant 915-15-29, and U.S. Public Health Service Grant 2K3-GM-17059.Program in Genetics and Department of Botany.Program in Genetics.     

Microorganisms of Striga hermonthica in Northern Ghana with Potential as Biocontrol Agents

A survey of microorganisms of Striga hermonthica Del. Benth., a root parasite of graminaceous crops, was conducted in northern Ghana in 1992. Thirteen fungal species were isolated from infected S. hermonthica plants. Fusarium spp. were the most prevalent, and were isolated from more than 90% of the S. hermonthica samples collected. Other fungi isolated were Alternaria alternata, Bipolaris specifera, Cladosporium oxysporum, Curvularia falax, Macrophomina phaseolina, Nodulisporium gregarium, Phoma sorghina and Sclerotium rolfsii.     

A plastid gene phylogeny of the non-photosynthetic parasitic <Emphasis Type="Italic">Orobanche</Emphasis> (Orobanchaceae) and related genera

The phylogenetic relationships of the non-photosynthetic Orobanche sensu lato (Orobanchaceae), which includes some of the economically most important parasitic weeds, remain insufficiently understood and controversial. This concerns both the phylogenetic relationships within the genus, in particular its monophyly or lack thereof, and the relationships to other holoparasitic genera such as Cistanche or Conopholis. Here we present the first comprehensive phylogenetic study of this group based on a region from the plastid genome (rps2 gene). Although substitution rates appear to be elevated compared to the photosynthetic members of Orobanchaceae, relationships among the major lineages Cistanche, Conopholis plus Epifagus, Boschniakia rossica (Cham. & Schltdl.) B. Fedtsch., B. himalaica Hook. f. & Thomson, B. hookeri Walp. plus B. strobilacea A. Gray, and Orobanche s. l. remain unresolved. Resolution within Orobanche, however, is much better. In agreement with morphological, cytological and other molecular phylogenetic evidence, five lineages, corresponding to the four traditionally recognised sections (Gymnocaulis, Myzorrhiza, Orobanche, Trionychon) and O. latisquama Reut. ex Boiss. (of sect. Orobanche), can be distinguished. A combined analysis of plastid rps2 and nuclear ITS sequences of the holoparasitic genera results in more resolved and better supported trees, although the relationships among Orobanche s. l., Cistanche, and the clade including the remaining genera is unresolved. Therefore, rps2 is a marker from the plastid genome that is well-suited to be used in combination with other already established nuclear markers for resolving generic relationships of Orobanche and related genera.     

New and remarkable microfungi in North Rhine Westphalia, Germany

During our investigation on microfungi in North Rhine Westphalia in the years 2002 and 2003 we were able to collect and identify some new and rare species of microfungi as parasites and saprophytes on wild and ornamental plants. Some of these like Erysiphe elevata (BURILL.) U. BRAUN & S. TAKAMATSU COMB. NOV. [=Microsphaera elevata BURILL.] on Catalpa bignonioides WALT., Erysiphe syringae-japonicae (U. BRAUN) U. BRAUN & S. TAKAMATSU [= Microsphaera syringae-japonicae U. BRAUN, M. aceris BUNKINA. KOMAROVSKIE CHTENIYA, Erysiphe acerina U. BRAUN & S. TAKAMATSU] on Acer campestre L. and Acer barinerve L., Mycosphaerella iridis (DESM.) SCHROET., Ectostroma iridis FR. and Volutella melaloma BERK. & BR on Iris pseudacorus L., Puccinia doronicella P. SYD. & SYD. on Doronicum columnae TEN., Ascochyta lamiorum SACC. S.L. I=A. phlomidis BUB. & WROB.) on Phlomis tuberosa L., Colletotrichum gloeosporides (PENZ.) SACC. on Passiflora coerulea L., Oidium hortensiae JOERST on Hydrangea macrophylla (THUNB.) SER., Puccinia horiana P. HENN. on Chrysanthemum vulgare (L.) BERNH., Lophodermium pinastri (SCHRAD.) CHEV., Leptostroma pinorum SACC., Sclerophoma pythiophila (CDA) HOHN., Lichenoconium boreale (KARST.) PETRAK. & SYD., Anthostomella formosa KIRSCHST. and Sphaeropsis sapinae (FR.) DYKO & SUTTON on Pinus nigra L. are new for Germany. All samples are located in the Herbarium ESS Mycotheca Parva, Collection G.B. Feige/N. Ale-Agha.     

Towards an understanding of the Sarcostemma viminale (Asclepiadaceae) complex

LIEDE, S. & MEVE, U., 1993. Towards an understanding of the Sarcostemma viminale (Asclepiadaceae) complex. All names in Sarcostemma sensu Bullock (Asclepiadaceae, Asclepiadeae, Cynanchinae) are listed and their current status evaluated. Chromosome numbers are given for most taxa. The typification of S. viminale is clarified. A new subspecies of S. viminale is described from the Orange Free State, South Africa, and relationships of the Namaqualand/Namibia populations are discussed.     

A GLOSSOPTERIS FLORA FROM THE OHIO RANGE,ANTARCTICA

Cridland , Arthur A. (Ohio State U., Columbus.) A Glossopteris flora from the Ohio Range, Antarctica. Amer. Jour. Bot. 50(2): 186–195. Illus. 1963.—Leaves of Glossopteris indica are the commonest fossils in the Mount Glossopteris Formation on Mount Schopf. Other fossils present are: Glossopteris ampla, G. anguslifolia, G. damudica, G. browniana, detached scales, sporangia of Arberiella containing bisaccate pollen grains, seeds of Samaropsis (principally S. longii), and some obscure fossils. These remains, and associated animal fossils, suggest that the Mount Glossopteris Formation is Permian. The plants evidently grew in a seasonal but favorable climate. These growth conditions indirectly support paleomagnetic calculations which indicate that in Late Permian time, Mount Schopf lay near latitude 50°S.     

Predicting Attitudes toward Press- and Speech Freedom across the U.S.A.: A Test of Climato-Economic,Parasite Stress,and Life History Theories

National surveys reveal notable individual differences in U.S. citizens’ attitudes toward freedom of expression, including freedom of the press and speech. Recent theoretical developments and empirical findings suggest that ecological factors impact censorship attitudes in addition to individual difference variables (e.g., education, conservatism), but no research has compared the explanatory power of prominent ecological theories. This study tested climato-economic, parasite stress, and life history theories using four measures of attitudes toward censoring the press and offensive speech obtained from two national surveys in the U.S.A. Neither climate demands nor its interaction with state wealth—two key variables for climato-economic theory—predicted any of the four outcome measures. Interstate parasite stress significantly predicted two, with a marginally significant effect on the third, but the effects became non-significant when the analyses were stratified for race (as a control for extrinsic risks). Teenage birth rates (a proxy of human life history) significantly predicted attitudes toward press freedom during wartime, but the effect was the opposite of what life history theory predicted. While none of the three theories provided a fully successful explanation of individual differences in attitudes toward freedom of expression, parasite stress and life history theories do show potentials. Future research should continue examining the impact of these ecological factors on human psychology by further specifying the mechanisms and developing better measures for those theories.     

ROOT INJURY AS A FACTOR IN THE ASSESSMENT OF CHEMOTHERA-PEUTANTS BY THE TOMATO FUSARIUM WILT TEST

Studies of the tomato Fusarium wilt test for screening chemotherapeutants were made by the writer at the Connecticut Agricultural Experiment Station, U.S.A., during 1951. The test compounds were applied on ten successive days to the roots of tomato plants growing in sand. The plants were then uprooted, their roots washed and dipped in a bud-cell suspension of F. oxysporum lycopersici and the plants re-potted. A standardized assessment of wilt and vascular discoloration was made some 21 days later, by which time the control plants were usually severely diseased. Several compounds greatly reduced disease severity.     

Severe sensitivity to ultraviolet radiation in anArabidopsis mutant deficient in flavonoid accumulation

A mutantArabidopsis thaliana L., which displays a dramatic increase in sensitivity to ultraviolet-B (UV-B) radiation compared with wild-type plants, has been isolated by chemical mutagenesis. This mutation appears to affect UV-tolerance specifically, since mutant plants are indistinguishable from wild type with respect to their degree of resistance to other forms of stress. The UV-sensitive mutation proved to be recessive and to segregate as a single Mendelian locus. This single gene defect was shown to lead to a block in the synthesis of a group of flavonoids which normally accumulate in developing wild-typeArabidopsis and which increase in concentration when plants are exposed to UV radiation. One of these compounds has been identified as a rhamnosylated derivative of the flavonol, kaempferol. The results suggest that one or more of the flavonoids whose production has been blocked in the UV-sensitive mutant is essential for the protection ofArabidopsis against UV-radiation damage. This constitutes further evidence that flavonoids play an important role in the protection of plants from the damaging effects of UV-B light.Abbreviations EMS ethyl methyl sulfonate - NMR nuclear magnetic resonance - uvs UV-sensitive Dedicated to Professor Hartmut K. Lichtenthaler on the occasion of his 60th birthdayThis work was supported by Cooperative State Research Service, U.S. Department of Agriculture, under Agreements Nos. 90-37280-5664 and 90-372780-5808 and by National Science Foundation Grant MCB 93-16496. We wish to thank Lola Peñarrubia, Elena del Campillo, Patrick Neil and Julie Montgomery for innumerable and fruitful discussions.     

草苁蓉属(列当科)分类的研究

本文详细比较了草苁蓉属和丁座草属(Xylanche)植物的形态特征,并在扫描电镜下观察了它们的种皮纹饰。发现G.Beck(1890)建立丁座草属时所依据的花部性状并不可靠,这些性状,尤其是花萼分裂度和心皮数目,本身就有变异。因此,作者将丁座草属归并入草苁蓉属(Boschniakia)中。     

Incidence of inhibitory pseudomonads in the Pacific Northwest

Incidence of pseudomonads inhibitory to the root growth of till and no-till seeded crops winter wheat (Triticum aestivum L.), pea (Pisum sativum), lentil (Lens culinaris), and no-till winter barley (Hordeum vulgare), top and bottom of a seeded slope, and on the weed downy brome (Bromus tectorum) was investigated. Pseudomonads on the rhizoplane of these plants ranged from 10⁶ to 10⁸ colony-forming units (cfu) per gram dry weight of root. Neither tillage management nor site on a seeded slope affected colonizing numbers. Total numbers of pseudomonads were reduced in a second sampling, particularly on winter barley roots. However, more inhibitory pseudomonads were found in the second sampling. Several of the isolates, both inhibitory and stimulatory from different host plants, were bioassayed against winter wheat seedlings. Generally, the effect was different on the winter wheat than on the host plant indicating the organisms had some specificity. Several pseudomonads were isolated that severely reduced downy brome root growth and not that of winter wheat. Contribution from Agric. Res. Serv., U S Dep. of Agric., in cooperation with the College of Agric, and Home Economics, Agric. Res. Center, Washington State Univ., Pullman, WA 99164. Scientific Paper No. 7491.     

宽叶韭及其近缘种不同居群的黄酮类化合物薄层层析研究

对宽叶韭的１３个居群及其变种木里韭和近缘种峨眉韭的叶片进行了黄酮类化合物的薄层层析（ＴＬＣ）分析,发现不同居群的木里韭、峨眉韭和具有相同生活习性的宽叶韭的层析图谱类型不受生态环境和染色体倍性的影响;依据层析图谱,宽叶韭可明显分为三个类型且与宽叶韭的生活习性相吻合,表明宽叶韭可能发生了种内分化。     

Histopathology and Host Range Studies of the Redwood Nematode Rhizonema sequoiae

Second-stage larvae of Rehizonma sequoiae Cid del Prado Vera et al. tunnel through the cortex of the redwood Sequoia sempervirens (D. Don) Endl. root to the vascular tissue where each developing female induces a single ovoid or occasionally spherical giant cell with a single ovoid to spherical nucleus containing one to four enlarged nucleoli. Nematode tunnels are filled with a gel material and often contain second-stage larvae and males. There is tissue necrosis around females, and cortical tissue is destroyed after infection by many second-stage larvae. R. sequoiae females developed to maturity on S. sempervirens, Acer macrophyllum Pursh, AInus rhombifolia Nutt., Libocedrus decurrens Torr, Pseudotsuga menziesii (Mirb.) Franco, and Sequoiadendron giganteum (Lindl.) Decne. In the Marin County, California, forest mature females were also found naturally infecting Lithocarpus densiflorus (Hook &Arn.) Rehd., Umbellularia californica (Hook &Arn.) Nutt., and Arbutus menziesii Pursh.