bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF PLANT GROWTH REGULATORS ON THE INFECTIVITY OF TOBACCO MOSAIC VIRUS
Authors: Weeraratne Victor , Rich Avery E.
Published: August 2008

A naturally occurring growth regulator, coconut meat extract, was tested for the inhibition of tobacco mosaic (TMV) virus infection. Coconut meat extract inhibited infection by 97%. The inhibitor in coconut meat extract was effective when the virus inoculation took place 8 days after the application of the inhibitor, but the inhibitor was ineffective when applied after inoculation with the virus. Aging in vitro for 64 days at 4 °C and at room temperature did not reduce the inhibitory effect of coconut meat extract, but dilution markedly reduced its inhibitory effect. Three commercially available growth regulators, indoleacetic acid, indolebutyric acid, and p-chlorophenoxyacetic acid, were tested at a concentration of 100 p.p.m., but their inhibiting activity was very low.
EFFECT OF GIBBERELLIC ACID ON WATER-SOLUBLE MACROMOLECULAR COMPONENTS OF LEAVES FROM DWARF-1 MUTANT OF CORN (ZEA MAYS L.)
Authors: Srivastava B. I. Sahai
Published: August 2008

The water-soluble macromolecular components of control and gibberellic acid treated leaves of dwarf-1 mutant of corn were analyzed by moving-boundary electrophoresis. Altogether, seven peaks were produced which represented the groupings of macromolecules with similar electrophoretic mobilities. Gibberellic acid changed the concentration and the composition of the macromolecular components, which indicated changes principally in the components of nucleic acids or proteins or both.
FURTHER EVIDENCE ON THE EFFECTS OF LIGHT ON RESPIRATION DURING PHOTOSYNTHESIS
Authors: Tregunna E. B. , Krotkov G. , Nelson C. D.
Published: August 2008

Chlorophyll-rich and chlorophyll-deficient leaves of soybean, peperomia, and corn were compared for the effects of previous illumination on the rate of carbon dioxide evolution in the subsequent dark period. An infrared carbon dioxide analyzer was used to measure these rates. It was found that the initial rate of carbon dioxide production in the dark was affected by previous illumination in proportion to the capacity of the leaves for photosynthesis. Light accelerated carbon dioxide production in green soybean and perperomia leaves, but inhibited it in green corn leaves.Using a Geiger tube to follow changes in the concentration of C14O2 around detached tobacco leaves, it was concluded that some recent product of photosynthesis was the substrate for the initial postillumination production of carbon dioxide. All above results indicated that there was a close relationship between the photosynthetic apparatus of the leaves and the production of carbon dioxide both during and immediately following a period of illumination.
LYSOPINE IN NORMAL AND IN CROWN-GALL TUMOR TISSUE OF TOMATO AND TOBACCO
Authors: Seitz E. W. , Hochster R. M.
Published: August 2008

The amino acid lysopine was found in the free state in both primary normal and crown-gall tumor tissue of growing tobacco (Nicotianatabacum) and tomato (Lycopersiconesculentum) plants. Identification was made by means of co-chromatography with synthesized lysopine, electrophoresis, and column chromatography. Quantitative analysis showed that tumor tissue contained about 24 times as much lysopine as normal tissue.
A NEW LEPTOSPHAERIA SPECIES, AN AGENT IN THE BIOLOGICAL CONTROL OF CERTAIN HYPODERMATACEAE
Authors: Darker Grant D.
Published: August 2008

Following the destruction of conifer needles by certain members of the Hypodermataceae, a number of secondary invaders find entry to the needles and compete for the food supply. These secondary fungi are beneficial in that they serve to prevent the maturation of the parasitic organisms and thus provide a natural biological control of the latter. Leptosphaeria faullii, sp. nov., and its presumed conidial state, Coniothyrium faullii, sp. nov., are secondary after Hypodermella mirabilis and Bifusella faullii.
THE INITIATION AND EARLY DEVELOPMENT OF THE SEED CONE OF DOUGLAS FIR
Authors: Owens John N. , Smith Frank H.
Published: August 2008

The initiation and early development of lateral vegetative, megasporangiate, and microsporangiate buds is described. The subsequent development of the megasporangiate cone prior to dormancy is described in detail. Initiation of lateral buds from cortical cells above the leaf axil occurs early in April and is similar in the three bud types. Apical zonation becomes apparent by mid-May but is less distinct in the microsporangiate primordium because of its smaller size. The microsporangiate bud remains distinctly smaller until microsporophyll initiation. Apical enlargement occurs in mid-July, at the end of the period of cataphyll initiation, and marks the onset of subsequent foliar initiation (leaves, bracts, and microsporophylls). Like the cataphylls, these foliar organs are presaged by procambial differentiation from the peripheral zone outward to the base of the presumptive primordium. No distinct apical initials appear in any of the foliar organs. A group of subapical initials is active during early development but they soon differentiate and further elongation occurs by intercalary growth. Bract initiation ends early in October. The apices of the three bud types show a similar growth periodicity and become greatly reduced in size and distinctness of zonation during foliar initiation. Scale initiation in the megasporangiate bud begins early in September and continues until the cones become dormant early in November. Scales are initiated from axillary cells at the base of the bracts. Apical zonation similar to other lateral shoots is present during early development but the organization changes to a type of submarginal growth.
SCLEROTINIA ARCTICA N. SP. ON CAREX FROM NORTHERN CANADA
Authors: Elliott Mary E.
Published: August 2008

A new species of Sclerotinia on Carex aquatilis var stans, S. arctica, is described. Large, black sclerotia produced in the culm bases of the host give rise to apothecia with discs 6–11 mm in diameter. It is compared with S. vahliana and S. dennisii on Eriophorum spp.
THE UTILIZATION OF NITROGEN COMPOUNDS, ESPECIALLY AMMONIA, BY A LOW-TEMPERATURE BASIDIOMYCETE
Authors: Ward E. W. B.
Published: August 2008

The nitrogen nutrition of a low-temperature basidiomycete, a cause of snow mold in Western Canada, was studied in submerged culture. L-Glutamine, L-asparagine, a number of amino acids, and urea supported excellent growth in a glucose – mineral salts medium supplemented with thiamine and pyridoxine, while several amino acids, acetamide, ethylamine, and methylamine were not utilized. D-Asparagine was not utilized, D-aspartic acid was utilized to a limited extent, while D-alanine supported as much growth as L-alanine. Nitrate and nitrite were not utilized and in initial experiments ammonium salts supported only limited growth, their utilization being accompanied by a rapid fall in the pH of the medium to inhibitory levels. Subsequently ammonium salts were found to be excellent sources of nitrogen provided the pH was controlled either by titration or by the inclusion of organic acids in the medium. A number of organic acids were found to be effective and, in general, their effectiveness was correlated with their buffering capacity within the pH range 3 to 6. Although pyruvic and α-ketoglutaric acids were taken up during growth it seemed improbable that they participated directly in ammonia utilization. With ammonium chloride as nitrogen source, changes in the pH, ammonia, total, and amino nitrogen levels were followed throughout growth when pyruvic acid, α-ketoglutaric acid, L-alanine, or L-glutamic acid were added to the medium. The results again indicated that pH was the main factor controlling growth. They also demonstrated that amino nitrogen is utilized for growth far more efficiently than ammonia nitrogen.
STUDIES ON THE EFFECT OF PSEUDOMONAS GLYCINEA ON SEPTORIA GLYCINES DEVELOPMENT ON FOLIAGE OF THE HAROSOY SOYBEAN GROWN UNDER CONTROLLED ENVIRONMENTAL CONDITIONS
Authors: Benedict W. G.
Published: August 2008

Conditions are described for growing soybeans in a plant growth chamber and for the development and study of bacterial blight, Pseudomonas glycinea (Coerper) Stapp, and of brown spot, Septoria glycines Hemmi. An investigation of a possible interrelationship between these two organisms during disease development revealed a marked increase in brown spot infection in the presence of bacterial blight. This resulted from a synergistic bacteria–fungus association of the two pathogens in doubly inoculated foliage of the soybean grown in the plant growth chambers.
HYPHODONTIA ALUTACEA IN NORTH AMERICA
Authors: Larsen Michael J.
Published: August 2008

Hyphodontia alutacea (Fries) Erikss. is a wood-rotting fungus found associated with a white rot of dead wood of conifers and angiosperms over a wide range in North America. The macroscopic and microscopic characters of the basidiocarp are described in detail and illustrated. Geographic distribution and substratum relationships are elucidated. Because of their macroscopic and microscopic similarities, Hyphodontia floccosa (Bourd. & Galz.) Erikss. and Hyphodontia subalutacea (Karst.) Erikss. are compared to H. alutacea. Distinguishing characters are given for these three species.
FACTORS AND PROCESSES IN THE GERMINATION OF DATURA FEROX L.
Authors: Soriano A. , Sánchez R. A. , Eilberg B. A. de
Published: August 2008

The germination of Datura ferox seeds is blocked immediately after ripeness by an inhibitor. The decoating of the seeds and certain storage conditions promote germination by favoring the diffusion of the inhibitor or its destruction.Seeds in which the germination blockage due to the inhibitor had been overcome behave as photoblastically positive, responding to the R–FR mechanism. During afterripening, the capacity of the skotomechanism increases as the inhibitor level decreases. The skotomechanism blockage does not disappear with low temperature or with alternating temperatures. On the other hand, high temperature reimposes this blockage.Gibberellic acid replaces the effect of red light, whereas thiourea is not effective.It is postulated, on the basis of the results obtained with this species, and the results of other authors, that the quantity of an oxidation product present, resulting from metabolic processes during storage or the action of red light, controls both germination and the possibility of germination being produced in conditions of light or darkness.
NEW OR LITTLE KNOWN NORTH AMERICAN STIPITATE HYDNUMS
Authors: Harrison K. A.
Published: August 2008

The following species new to science are described; Steccherinum crassiusculum K. Harrison sp. nov., Phellodon atratus K. Harrison sp. nov., Hydnum rimosum K. Harrison sp. nov., H. fuscoindicum K. Harrison sp. nov., H. cyanellum K. Harrison sp. nov., H. ustale K. Harrison sp. nov., H. calvatum K. Harrison sp. nov., H. calvatum var. odoratum K. Harrison var. nov., Hydnellum scleropodium K. Harrison sp. nov., H. cyanopodium K. Harrison sp. nov., H. cyanodon K. Harrison sp. nov., H. chrysinum K. Harrison sp. nov., H. septentrionale K. Harrison sp. nov., H. cumulatum K. Harrison sp. nov., H. pineticola K. Harrison sp. nov., H. subsuccosum K. Harrison sp. nov., H. nigellum K. Harrison sp. nov., H. regium K. Harrison sp. nov. Hericium abietis (Weir ex Hubert) K. Harrison comb. nov. is described in detail. Also included are detailed descriptions from fresh material of Hydnum fuligineo-violaceum Kalch. and Hydnellum humidum Banker recently collected by Dr. A. H. Smith in Michigan, together with additional details of microscopic comparisons and chemical reactions for eight recently described species from Nova Scotia.A peculiar reaction of certain hyphae in the stipitate hydnums to Melzer's solution is described and referred to as "apparent amyloid". It has been found to be associated with a blue-green reaction to a 3% KOH solution and has been used as a quick test for separating certain species.
CRITICAL OBSERVATIONS ON THE PARASITISM OF NEW WORLD MISTLETOES
Authors: Kuijt Job
Published: August 2008

The parasitism of the mistletoes of the Americas is surveyed and integrated with recent observations on haustorial structure and mode of attack of the mistletoes of Central America and California. The occurrence and behavior of epicortical roots is traced in the genera Struthanthus, Phthirusa, and Antidaphne. Special consideration is given to the gross structure and development of the primary haustorial contact. A final section deals with the parasitism of mistletoes on leaves, on other mistletoes, and on themselves.
THE LEPTOGRAPHIUM COMPLEX. HANTZSCHIA AUERSWALD
Authors: Kendrick W. Bryce
Published: August 2008

Leptographium phycomyces (Auersw.) Grosm. is transferred to Phialocephala Kendrick because its sporogenous cells are phialides. It is illustrated and re-described from the host and in culture.
CONIDIAL STATES OF SOME BOTRYOSPHAERIA SPECIES ON VITIS AND QUERCUS
Authors: Shoemaker R. A.
Published: August 2008

Botryosphaeria obtusa (Schw.) n. comb, and B. stevensii n. nom. occurring on cultivated grapes, and B. quercuum (Schw.) Sacc. and B. melanops (Tul.) Wint. on Quercus spp. are distinguished primarily by characteristics of their conidial states which are illustrated, described, and separated by a key. Canadian collections in the National Mycological Herbarium support the following host range and geographic distribution: B. quercuum on Quercus spp. in Nova Scotia, Quebec, and Ontario; B. melanops on Quercus spp. in Ontario; B. obtusa on Amelanchier, Crataegus, Juglans, Malus, Ribes, Sorbus, and Vitis spp. in Nova Scotia, Quebec, Ontario, and Saskatchewan; B. stevensii on Vitis sp. in Ontario.
BARK MOISTURE RELATIONSHIPS IN WESTERN HEMLOCK BRANCHES INFECTED BY DWARF MISTLETOE
Authors: Baranyay J. A.
Published: August 2008

Investigations of bark moisture in branches of western hemlock, Tsuga heterophylla (Raf.) Sargent, infected by western dwarf mistletoe, Arceuthobium campylopodum Engelm. forma tsugensis Gill, were carried out in good and poor growing sites on the Campus Forest and Research Forest, respectively, of the University of British Columbia. Bark moisture was determined in terms of relative turgidity.Major changes in the moisture content of non-invaded bark occurred in both sites, but the changes were more pronounced in the poor site than in the good site. The relative turgidities of non-invaded bark were less than 80% for 5.9% of the sampling period, June to February inclusive, in the good site, and for 33.3% of the time in the poor site. Bark moistures were more sensitive to changes of precipitation and temperature in the poor site than in the good site, because of the shallow rooting habit of trees and the propensity of the soil in this site to drought.Dwarf mistletoe did not affect bark moisture in the non-invaded portions of branches, but the moisture content of invaded bark was variously affected depending upon the season of year and the age of the infection. When bark moistures were generally low, for example, in April in the good site and June in the poor site, the moisture content of bark that had been invaded for less than 10 years was highest at the centers of infections and lowest at the periphery. At the same time of year but in bark that had been invaded for more than 10 years, the moisture content was highest at the periphery of infections while at the centers it was similarly low to that of the non-invaded bark of the same branches. When bark moistures were generally high, for example, in July in the good site and early August in the poor site, the moisture content of bark in the young infections remained high throughout the entire invaded area. At the same time of year but in the old infections, bark moisture was lowest at the center of infections, and at these times the only portion of an infected branch having a bark moisture content of less than 80% relative turgidity was the center of infection. This may explain the successful establishment of parasitic fungi at these locations.
CHROMOSOME NUMBERS OF FERNS IN ONTARIO
Authors: Britton Donald M.
Published: August 2008

Chromosome numbers are given for 17 species of ferns. Most of the determinations of chromosome number confirm reports for these species from other countries or other localities. New determinations are given for Cheilanthes lanosa (Michx.) D. C. Eaton (n = 30) and Cryptogramma stelleri (S. G. Gmel.) Prantl (n = 30).
FURTHER STUDIES ON THE PHYSIOLOGY OF CLADOSPORIUM FULVUM CKE. AND RESISTANCE IN TOMATO
Authors: Lowther Ruth L.
Published: August 2008

Some host–parasite interactions of the C. fulvum – tomato leaf complex have been correlated with degrees of utilization in vitro by races of the pathogen of metabolites which have been shown to occur in different amounts in some tomato hosts which react differentially to them. Similarities and differences in the behavior of three pathogenic races were noted when the plants were grown in a number of amino nitrogen and sugar carbon sources. Similarities are interpreted as representing species characteristics; on the other hand, differences, including colony colors in glutamine and γ-aminobutyric acid, appear to be racial characteristics. Further evidence suggesting that certain host metabolites modify or condition the pathogenic expression was obtained from studies of the effect on pathogenicity of culture media differing in amino nitrogen content. From a comparison of the metabolites of host–pathogen complexes of differing reaction types, some insight was gained into probable nutritional requirements for a race 1 susceptible response. Conversely, where these differed in other reaction-type complexes, clues were obtained regarding possible reasons for resistance to this race.
SOME CHROMOSOME NUMBERS OF GAREX SPECIES OF CANADA AND ALASKA
Authors: Moore R. J. , Calder J. A.
Published: August 2008

Chromosome counts of 36 taxa and two hybrids of Carex are presented: 18 are new, 11 verify previous counts, 5 differ by 2 from previous counts, and 2 differ more widely from reported counts. Taxonomic notes relating to a few species arc included.
PHYSIOLOGICAL AND CYTOLOGICAL STUDIES OF BASIDIOSPORE REPETITION IN RHIZOCTONIA SOLANI KÜHN
Authors: Whitney H. S.
Published: August 2008

Mycelium of a clone of Thanatephorus cucumeris (Frank) Donk (Rhizoctonia solani Kühn) produced ether-soluble substances which, when incorporated into water agar, caused basidiospores to shift from germ tube development to repetition. Repetition activity was localized in chromatograms by bioassay. Germ tubes less than 48 hours old produced ballistospores when transferred from water agar to fruiting cultures. Cells of older hyphae had apparently lost this capacity. Repetition spores, and ballistospores produced by germ tubes, were uninucleate and gave rise to cultures typical of the parent fungus. The relevance of repetition to survival and to phylogeny was discussed.
STUDIES OF MULTIPLE ALLELISM IN THE MYXOMYCETE DIDYMIUM IRIDIS
Authors: Mukherjee K. L. , Zabka George G.
Published: August 2008

Heterothallism in three physiological races of Didymium iridis collected from Honduras (Mexico), Hawaii, and Australia are reported. Pure clone matings of these races are found to be governed by multiple alleles of incompatibility factors, heterozygosity of which leads to zygote formation. Two of these races behave identically in their mating reactions although their plasmodia are non-fusable. Existence of a two-locus system with linkage of parental alleles is suggested to explain the mating behavior of the pure clones handled and the absence of tetrapolarity. Because of aging and artificial culture, intraracial sterility develops in the pure clones. These clones retain their interracial fertility. Sporadic Plasmodia occasionally form in some of the pure clones probably because of a localized mutation. Zygote formation with the mutated cell apparently leaves the remaining clone population uncontaminated.
A NEW SPECIES OF FUSARIELLA FROM ISRAEL
Authors: Chabelska-Frydman Chaja
Published: August 2008

Fusariella hughesii sp. n. is described and illustrated. The fungus was isolated from the dispersal units of Phalaris minor Retz. and Trigonella arabica Del.
FINE STRUCTURE OF WHEAT STEM RUST UREDOSPORES
Authors: Williams P. G. , Ledingham G. A.
Published: August 2008

The fine structure of uredospores and germ tubes of Puccinia graminis f. sp. trilici is described from electron micrographs of cells fixed in KMnO4. In terms of their principal cytoplasmic structures (nuclei, mitochondria, endoplasmic reticulum, and protoplasmic and vacuolar membranes) these cells bear a general resemblance to other fungi and higher plants but differences between resting cells and germ tubes were noted in the size of oil bodies and the structure and extent of the endoplasmic reticulum.
CHROMOSOME NUMBERS OF THE FAMILY CRUCIFERAE. I
Authors: Mulligan Gerald A.
Published: August 2008

Chromosome numbers are given for 69 collections of 24 species of Cruciferae in the genera Alyssum, Arabidopsis, Arabis, Barbarea, Cakile, Eutrema, Hali-molobos, Nasturtium, Rorippa, Thellungiella, and Turritis. The following chromosome numbers are reported for the first time: Alyssum desertorum, n = 16; Arabis canadensis, 2n = 14; A. divaricarpa, 2n = 13 + 2B, 14, 20 + 2B, 21, 28; A. drummondii, 2n = 20; A. holboellii, 2n = 13 + 2B, 20 + 2B; A. lemmonii, 2n = 14; A. lyallii, 2n = 21; A. lyrata, 2n = 32; A. pendulocarpa, 2n = 14; Barbarea orthoceras, 2n = 16; Cakile edentula, 2n = 18; Rorippa curvisiliqua, 2n = 16; Thellungiella salsuginea, 2n = 14. It is concluded that species of Arabis native to North America and western Greenland have the base number x = 7 and many of them are apomictic whereas Eurasiatic species of this genus have an x = 8 base number and are sexual.
RESISTANCE TO CLADOSPORIUM FULVUM CKE. OBTAINED FROM WILD SPECIES OF TOMATO
Authors: Kerr E. A. , Bailey D. L.
Published: August 2008

In the last 20 years several varieties and breeding lines of tomato have been developed which possess immunity from C. fulvum races 1 to 9. Vagabond, Vinequeen, and V548 obtained their immunity from L. hirsutum Humb. and Bonpl.; V501 from L. hirsutum var. glabralum Muller; V542, Vantage, Waltham Mold Proof Forcing No. 22, etc. from L. peruvianum (L.) Mill.; and V545 from L. pimpinellifolium (Jusl.) Mill. Studies are reported herein on the genetic bases of resistance in these varieties.Single genes for immunity from C. fulvum race 6 were isolated in these varieties and breeding lines. Crosses between the varieties indicated that the immunity from all of these sources is conditioned by the same gene or by genes that are very closely linked. Differential races must be found before this point can be determined with certainty. The gene from L. hirsutum which confers immunity to race 6 in Vinequeen is designated as Cf4. Cf4has been shown to be located on chromosome 1, probably near Cf1.L. hirsutum, L. pimpinellifolium, and L. esculentum var. cerasiforme Mill. among them have several other genes conferring a lower level of resistance to race 6.
CLADOSPORIUM FULVUM RACE 10 AND RESISTANCE TO IT IN TOMATO
Authors: Bailey D. L. , Kerr E. A.
Published: August 2008

A new race of Cladosporium fulvum Cke., the tomato leaf mold pathogen, appeared on the tomato lines Purdue 38 and Purdue 135 in commercial greenhouses in the vicinity of Cincinnati, Ohio, in the fall of 1962. These lines incorporate from L. hirsutum the gene Cf4, which confers immunity to races 1 to 9. Greenhouse inoculations indicate that race 10 is similar to race 1 in pathogenicity against Cf1, Cf2, and Cf3. Varieties such as Vetomold, Tucker's Forcing, and Manalucie, which contain Cf2, are accordingly immune from race 10.
THE INDUCTION OF GROWTH IN EXPLANTED TISSUE OF THE BANANA FRUIT
Authors: Ram H. Y. Mohan , Steward F. C.
Published: August 2008

A method of obtaining proliferative growth of explanted fruit tissue from a number of cultivated varieties of bananas at different stages of development has been described.The explants weighing above 70 mg grow more rapidly than smaller pieces. Entire slices of the fruit, or only the axial part or pulp tissue have been cultured.A culture medium, as suggested by White, consisting of mineral salts, sucrose (2%), and vitamins, and solidified with 0.5% agar served as the basal nutrient medium. The chief supplements were various concentrations of casein hydrolysate; coconut milk; 2,4-D; benzothiazole-2-oxyacetic acid (BTOA); coumarin; 2,3,6-trichlorophenylacetic acid and other substituted phenylacetic acids; kinetin; adeninesulphate; and indoleacetic acid (IAA).The growth was recorded chiefly as the increment of fresh weight although dry weight and cell numbers were estimated in one experiment.Contrary to expectation the tissue from mature bananas responded better to the externally supplied growth substances than that from younger fruit. In fact the capacity for cell division did not decrease even in the pulp of the banana fruit as normally harvested for shipment. However, the tissue from postclimacteric fruit is incapable of any recrudescence of growth. Climacteric, therefore, seems to determine the point of no return beyond which the cells will not grow.Some growth occurred on the basal medium, but the best growth was obtained when 2,4-D; 2,3,6-TPA; or BTOA was added. Coconut milk increased the cell number but not markedly the fresh weight, depressed the effect of 2,4-D, but enhanced the response to 2,3,6-TPA. Among the numerous chloro-substituted phenylacetic acids tried, 2,3-; 2,6-; and 2,3,6-TPA were the most active. Adenine sulphate (in combination with IAA) enhanced the division of pulp cells.The ability to respond to the culture treatments is genetically controlled. Tissue from 'Lacatan' and 'Robusta'; 'T23' and 'T12' bananas of the same age and grown under identical conditions show a great deal of variation in their response to the different growth substances.It is the pulp region of the fruit which is most responsive to growth substances. A fluffy callus capable of being subcultured is produced from the pulp. Starch and other ergastic bodies are usually absent in the callus cells. No differentiation into organs has, however, been observed. The funiculi enlarge but do not form callus; the seeds are not affected.The utility of this technique for a further understanding of the problems of growth and senescence of fruits is discussed.When the explants were cultured in liquid media containing 2,4-D (with or without coconut milk) or 2,3,6-TPA in special glass tubes mounted on a wheel and slowly rotated around a horizontal shaft, a number of cells sloughed off into the bathing fluid. These were of diverse shapes and sizes. Aliquots of the liquid containing free cells have been successfully subcultured. However, under complete isolation and constant observation divisions in single cells were not observed.
A NEW PSYCHROPHILIC FUNGUS CAUSING GERMINATION FAILURE OF CONIFER SEEDS
Authors: Epners Z
Published: August 2008

The germination of coniferous seeds has been very low for several years at the Province of Ontario Nurseries located at Midhurst and Orono, in extreme cases being reduced to only 2%.Between 1959 and 1963 seeds which had failed to germinate were collected from beds of Pinus resinosa Sol., Pinus sylvestris L., Pinus strobus L., and Picea glauca (Moench.) Voss. From all such seeds tested a psychrophilic fungus was isolated, which grows between −1 and 27 °C but does not grow at 30 °C. In such non-germinated seeds the fungus is found in all cells of the endosperm and embryo, but instead of rotting the seeds, it mummifies them. The fungus was found in a viable state in infected seed [Formula: see text] years after these were sown.The fungus has not yet been identified and no record has been found of its previous isolation. In this work it has been called the seed-fungus (S-fungus). It is not a damping-off fungus since it does not kill the seedlings before or as they emerge from the soil and, even when seedling stems are soft and succulent, it does not cause root rot or top killing. Under favorable conditions the fungus may kill 100% of conifer seeds in infested soil. Control was achieved through pelleting the seeds with Captan.The fungus produces sympodiospores and has some affinity with the genera Costantinella and Nodulisporium, but differs significantly from them.
FURTHER STUDIES ON NATURAL SELECTION AMONG HYBRIDS OF CARDUUS ACANTHOIDES AND CARDUUS NUTANS
Authors: Moore R. J. , Mulligan G. A.
Published: August 2008

A third 5-year survey made in 1962 of Carduus acanthoides, C. nutans, and their hybrids in Grey Co., Ontario, revealed that a great decrease in these populations had occurred. C. acanthoides and hybrids similar to this species had survived better than C. nutans but very little spread of either species seemed to have occurred in 1957–1962. In experimental plots the hybrid has been made and backcrossed to the parental species. The species differ in chromosome number (C. acanthoides, 2n = 22; C. nutans, 2n = 16) and hybrids have intermediate numbers. Evidence was found from field and experimental studies that the progeny of the F1 hybrid included a greater proportion of seedlings with the higher chromosome numbers than with the lower and intermediate numbers. It is suggested that this selection may operate through the rejection of the longer chromosomes received from C. nutans, which, in certain zygotic combinations may constitute an excess of chromatin lethal to the zygote.
DEVELOPMENTAL STUDIES ON EUPHORBIA ESULA L.: APICES OF LONG AND SHORT ROOTS
Authors: Raju M. V. S. , Steeves T. A. , Naylor J. M.
Published: August 2008

In both indeterminate long roots and determinate short roots of Euphorbia esula L., the promeristem usually consists of three meristematic layers. One of these represents the stelar pole, the second is continuous with the cortex, and the most distal appears to initiate the root cap – epidermis complex. Variations in this pattern are noted. Autoradiographs of apices of roots supplied with thymidine-H3 under field conditions demonstrate the existence of a region of low nuclear incorporation during a 24 or 48 hour period at the summit of the root axis in long roots. This region corresponds to the quiescent center described by previous authors. Short root apices consistently lack such a region. The pattern of nuclear incorporation of thymidine-H3 suggests that cell division is infrequent or absent in the center of the apex of long roots but not of short roots. Quiescence is thus a phenomenon which is superimposed upon the organization of the root apex in this species, and its presence or absence seems to be related to the developmental potentiality of the root. In many long roots the size of this quiescent region exceeds that of the region which may reasonably be designated the promeristem.
ESTIMATION OF GROWTH – TIME TEMPERATURE CHARACTERISTICS FOR ISOLATES OF FOMES PINI, A HEART ROT FUNGUS
Authors: Paine Lee A. , Schwarzbart Gideon , O'Regan William G.
Published: August 2008

Regression analysis techniques were applied to an estimation of three-dimensional surfaces representing the growth of Fomes pini as a function of time and temperature. These methods were judged to be valuable in their economy of data and in their provision of readily available plotting points for any desired cross section of the surface.The growth pattern of F. pini taken from Douglas fir was distinct from that of the form of F. pini found on nearby white fir. Growth of isolates from Douglas fir was more than twice that of white fir isolates after 18 days at near-optimum temperatures on malt agar. Estimates of growth trends and optimum temperatures were examined both for individual isolates of F. pini and for averages of isolates from the two host species, Douglas fir and white fir. Results suggest that chronological changes in the optimum temperature may be affected by the relation between the storage temperature preceding initial measurements and the terminal optimum temperature.
DEVELOPMENTAL MORPHOLOGY OF THE ROOT OF SELAGINELLA KRAUSSIANA A. BR. AND SELAGINELLA WALLACEI HIERON.
Authors: Webster T. R. , Steeves T. A.
Published: August 2008

The origin and development of the root in the isophyllous Selaginella wallacei and the anisophyllous S. kraussiana have been investigated, and the observations agree closely with those previously made by the authors on the isophyllous S. densa. In both species the root arises from an angle-meristem on the upper surface of the stem at the angle of each unequal terminal branching of the shoot. In its early development, the root meristem is not covered by a cap, but after a small amount of growth, a root cap is initiated as a result of the formation of distal segments by the apical cell and its immediate derivatives. Soon after cap formation has begun the root meristem undergoes terminal branching beneath the root cap, but there is a considerable delay before branching of the root is visible externally. In both of the species investigated, as previously in S. densa, no evidence for a rhizophore or for endogenous root origin could be found. These observations are discussed in the light of reports by previous workers in which similar structures are interpreted as rhizophores bearing endogenous roots.
A SEROLOGICAL COMPARISON OF ISOLATES OF FOMES ROSEUS AND FOMES SUBROSEUS
Authors: Madhosingh C.
Published: August 2008

Diploid and haploid isolates of Fomes roseus and F. subroseus were compared serologically. Immune sera, developed against an isolate from each species, were caused to react with the mycelial extracts and residual media of diploid and haploid isolates of both species using the agar double-diffusion technique. Similar precipitin lines occurring among all the reactants indicated similarity and serological relationship between the two species. In addition there were precipitin lines which were species and isolate specific. The combination of intravenous and intramuscular inoculations with adjuvant produced a titer of 1/2560 which was higher than that obtained by intravenous inoculations only.
Changes in the Benthic Community of a Small Precambrian Lake following the Introduction of Yellow Perch, Perca flavescens
Authors: Post John R. , Cucin Dan
Published: August 2008

The introduction and proliferation of yellow perch, Perca flavescens, in Little Minnow Lake, Algonquin Park, Ontario, resulted in changes in biomass and size structure of the benthic community. Biomass, mean organism weight, and density data are presented for nine groups of benthic macroinvertebrates for two years before and one year after perch introduction. An approximately 60% reduction in total benthic biomass and an approximately 50% reduction in mean weights occurred in the littoral zone after perch introduction. Vertically migrating profundal benthos showed an approximately 30–60% reduction in mean organism weight but no significant change in biomass. We conclude that fish predation can significantly alter species composition, skew size structure towards smaller invertebrates, and reduce total benthic biomass.
Tri- and Tetra-Chloroveratrole, Metabolites Produced by Bacterial O-Methylation of Tri- and Tetra-Chloroguaiacol: An Assessment of Their Bioconcentration Potential and Their Effects on Fish Reproduction
Authors: Neilson Alasdair H. , Allard Ann-Sofie , Reiland Sven , Remberger Mikael , Tärnholm Anders , Viktor Tomas , Landner Lars
Published: August 2008

We have demonstrated that strains of bacteria belonging to the genera Pseudomonas and Acinetobacter possessed the ability to transform, by O-methylation, components of spent bleachery effluent such as 4,5,6-trichloroguaiacol and high molecular weight chlorinated lignin. O-Methylation could be enhanced by the presence of a cosubstrate such as succinate or 4-hydroxybenzoate. We have used zebra fish (Brachydanio rerio) to examine bioconcentration potential, toxicity to embryos and larvae, and the sensitivity of the offspring of exposed adults. Bioconcentration factors (total wet weight) on a logarithmic scale were 3.5 and 4.4 for 3,4,5-trichloroveratrole and tetrachloroveratrole, respectively. The potential for bioconcentration of the other neutral metabolites was inferred from estimated values of the octanol–water partition coefficients. 3,4,5-Trichloroveratrole, tetrachloroveratrole, pentachloroanisole, and 1,2,3-trichloro-4,5,6-trimethoxybenzene had threshold toxic concentrations to zebra fish embryos and larvae of 450, 100, 2.8, and 450 μg∙L−1, respectively, and all of them were capable of inducing, at somewhat lower concentrations, various deformations including curvature of the larvae and distortion of the notochord. Experiments on the effect of preexposure of adults to tetrachloroveratrole at a concentration of 16 μg∙L−1 showed that the offspring were adversely affected, e.g. in a decreased viability of the embryos, lowered median survival time for larvae, and greater sensitivity to tetrachloroveratrole. Both 3,4,5-trichloroveratrole (5–150 μg∙kg liver fat−1) and tetrachloroveratrole (40–400 μg∙kg liver fat−1) were detected in fish from localities subjected to discharge of bleachery effluent, and were absent in fish from uncontaminated localities. Identification of these compounds was based on gas chromatographic, and for tetrachloroveratrole, mass spectrometric, comparison with authentic compounds. We conclude that not only compounds present in bleachery effluent, but those that may be produced in the environment by bacterial O-methylation, have potentially hazardous biological activities. These results shed fresh light on a hitherto neglected aspect of environmental hazard assessment, and we suggest that data for a given compound must be supplemented with that for metabolites that could be produced in the environment.
Life history patterns and trophic ecology of Trichoptera in two Alaskan (U.S.A.) subarctic streams
Authors: Irons III John G.
Published: August 2008

Monument Creek and West Fork, two interior Alaskan streams that are tributaries of the Chena River, are characterized by low water temperatures, low allochthonous input and periphyton biomass, and lengthy ice cover. Nine species of Trichoptera were found: Rhyacophila vofixa (Rhyacophilidae), Glossosoma verdona, Glossosoma alascense (Glossosomatidae), Brachycentrus americanus (Brachycentridae), Hydatophylax variabilis, Ecclisomyia conspersa, Onocosmoecus unicolor, Chyranda centralis, and Apatania crymophila (Limnephilidae). There were four shredders, three scrapers, one omnivore, and one predator. Within the shredder and scraper guilds, species had partially overlapping univoltine life histories, perhaps allowing functionally similar species to use the same food resources. The trichopteran fauna of interior Alaska seems to be composed of species typical of boreal forest, with arctic, western montane, and Siberian influences.
Plasma levels of vitamin D and some metabolites in marine mammals
Authors: Keiver K. M. , Ronald K. , Draper H. H.
Published: August 2008

Levels of vitamin D, 25-hydroxyvitamin D, 24,25-dihydroxyvitamin D, and calcium were determined in the plasma of various captive and wild pinniped and cetacean species. Vitamin D (< 0.4–5 ng∙mL−1) and 25-hydroxyvitamin D (4–84 ng∙mL−1) levels in the pinniped plasma were similar to those found in nonmarine mammals. 24,25-Dihydroxyvitamin D levels in seals (3–48 ng∙mL−1) were high compared with those of other mammals, and the ratios of 24,25-dihydroxyvitamin D to 25-hydroxyvitamin D in fasting pups were extremely high. The belugas and bottlenosed dolphins had very high levels of both 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D compared with the pinnipeds and other mammals, but plasma calcium levels were normal for these species of cetaceans.
Ecological energetics of Palaearctic Tetraonidae in relation to chemical composition and digestibility of their winter diets
Authors: Andreev A. V.
Published: August 2008

Parameters of digestion and energetics of free-living grouse were plotted against body mass to determine whether a general relationship exists between quantitative food intake, digestibility, and energy demands of individuals of different sizes, and to clarify the relationship between chemical composition of the diet and individual energetic demands of different species. Regression analysis showed a positive correlation between each of the parameters (except dry mass of caecal faeces) and body mass, reflecting a relationship between differences in chemical composition of the browse in the diets and its digestibility. Modelling intermediary metabolism in three grouse species revealed that about 50% of metabolizable energy originated from carbohydrate oxidation; the rest was shared among fiber (9–35%), protein (9–14%), and crude fat (12–25%). The more nitrogen in the diet, the higher were estimates of total digestibility, as well as those of fiber and fat. A generalized model of nitrogen demands of individuals is proposed and predictions from the model are compared with particular determinations based upon actual data from different species. The digestibility of natural grouse diets, and consequently available energy, is essentially dependent upon the concentration of protein in the diet. This suggests that it is necessary for grouse to exceed the minimal physiological level of nitrogen intake, not only to create reserves, but also to function effectively in the presumed need to detoxify and digest those fractions of the diet that are difficult to absorb.
Seasonal variation in diet digestibility of pine voles
Authors: MacPherson Sandra L. , Servello Frederick A. , Kirkpatrick Roy L.
Published: August 2008

Seasonal and habitat variation in diet digestibility of pine voles (Microtus pinetorum) in four apple orchards was estimated using regression equations and the Van Soest analysis of stomach contents. The estimated percent digestible energy of diets in the four orchards varied from 57 to 72% during the year but a uniform seasonal pattern was not found among orchards. Weights of stomach contents declined markedly during winter in all four habitats.
A mutant strain of terrestrial snails (Achatina fulica), exhibiting a supernumerary penis
Authors: Chase Ronald
Published: August 2008

In normal snails, hermaphroditic copulatory organs are situated on the right side of each animal. Mutant animals of the species Achatina fulica, isolated from a laboratory colony, possess a supernumerary penis, a supernumerary retractor muscle, and a supernumerary genital atrium, all on the left side. In some cases, apparent examples of supernumerary vaginas and vasa deferentia are also present. All supernumerary organs are symmetrically positioned with respect to the normal organs. A study of the genetic mechanism of inheritance is currently incomplete, but suggests that the phenotype is determined by a single gene mutation with either dominant or recessive properties. These observations provide the opportunity for a genetic analysis of development.
CONSTRAINTS ON TRANSITION REDSHIFT AND DECELERATION PARAMETER FROM RECENT OBSERVATIONS
Authors: LU JIANBO , XU LIXIN , LI JIECHAO , LIU HONGYA
Published: August 2008

In this paper, the 1σ confidence level of transition redshift and present deceleration parameter are studied using modified Chaplygin gas (MCG) model from recent observations: the 182 Gold SNe Ia, three-year WMAP, SDSS baryon acoustic peak and X-ray gas mass fraction in clusters. Concretely, the best fit values of the transition redshift and present deceleration parameter with the 1σ confidence level are [Formula: see text] and [Formula: see text], which indicate the best fit values of zT and q0 for MCG case are surprisingly close to the central values given by Refs. 20 and 21. Furthermore, we plot the evolution of cosmological quantities from MCG model by using the best-fit parameters given by combining constraint, and compare them with ΛCDM model.
NONCOMMUTATIVE SYMMETRIC FUNCTIONS AND THE INVERSION PROBLEM
Authors: ZHAO WENHUA
Published: August 2008

Let K be any unital commutative ℚ-algebra and z = (z1, z2, …, zn) commutative or noncommutative variables. Let t be a formal central parameter and K[[t]]〈〈z〉〉 the formal power series algebra of z over K[[t]]. In [29], for each automorphism Ft(z) = z - Ht(z) of K[[t]]〈〈z〉〉 with Ht=0(z) = 0 and o(H(z)) ≥ 1, a [Formula: see text] (noncommutative symmetric) system [28] ΩFthas been constructed. Consequently, we get a Hopf algebra homomorphism [Formula: see text] from the Hopf algebra [Formula: see text] [9] of NCSFs (noncommutative symmetric functions). In this paper, we first give a list for the identities between any two sequences of differential operators in the [Formula: see text] system ΩFtby using some identities of NCSFs derived in [9] and the homomorphism [Formula: see text]. Secondly, we apply these identities to derive some formulas in terms of differential operator in the system ΩFtfor the Taylor series expansions of u(Ft) and [Formula: see text]; the D-Log and the formal flow of Ftand inversion formulas for the inverse map of Ft. Finally, we discuss a connection of the well-known Jacobian conjecture with NCSFs.
GENCLO AND TERMEQUIV ARE EXPTIME-COMPLETE
Authors: MAŠULOVIĆ DRAGAN
Published: August 2008

In 1999, Bergman et al. showed that the following two problems are EXPTIME-complete: GENCLO, which decides whether an operation on a finite set A belongs to a clone generated by a finite set of operations on A; and TERMEQUIV, which decides whether two algebras on the same finite set and with finitely many fundamental operations are term-equivalent. However, the proof of one of the key statements was not correct. Using the techniques proposed by Bergman et al., in this paper we present the correct proof.
REPRESENTATIONS OF THE SYMPLECTIC ROOK MONOID
Authors: LI ZHENHENG , LI ZHUO , CAO YOU'AN
Published: August 2008

In this paper, we concern representations of symplectic rook monoids R. First, an algebraic description of R as a submonoid of a rook monoid is obtained. Second, we determine irreducible representations of R in terms of the irreducible representations of certain symmetric groups and those of the symplectic Weyl group W. We then give the character formula of R using the character of W and that of the symmetric groups. A practical algorithm is provided to make the formula user-friendly. At last we show that the Munn character table of R is a block upper triangular matrix.
INTERSECTION OF SUBGROUPS IN FREE GROUPS AND HOMOTOPY GROUPS
Authors: BAUES HANS-JOACHIM , MIKHAILOV ROMAN
Published: August 2008

We show that the intersection of three subgroups in a free group is related to the computation of the third homotopy group π3. This generalizes a result of Gutierrez–Ratcliffe who relate the intersection of two subgroups with the computation of π2. Let K be a two-dimensional CW-complex with subcomplexes K1, K2, K3 such that K = K1 ∪ K2 ∪ K3 and K1 ∩ K2 ∩ K3 is the 1-skeleton K1 of K. We construct a natural homomorphism of π1(K)-modules [Formula: see text] where Ri = ker {π1(K1) → π1(Ki)}, i = 1,2,3 and the action of π1(K) = F/R1R2R3 on the right-hand abelian group is defined via conjugation in F. In certain cases, the defined map is an isomorphism. Finally, we discuss certain applications of the above map to group homology.
LIMIT PRESERVATION PROPERTIES OF THE GREATEST SEMILATTICE IMAGE FUNCTOR
Authors: JANELIDZE GEORGE , LAAN VALDIS , MÁRKI LÁSZLÓ
Published: August 2008

We study what kinds of limits are preserved by the greatest semilattice image functor from the category of all semigroups to its subcategory of all semilattices.