bluuebunny/crossref_metadata_2025 huggingface dataset:
A new thermophilic fungus from mushroom compost: Thielavia thermophila spec. nov.
Authors: Fergus C. L. , Sinden J. W.
Published: September 2008

A new thermophilic, heterothallic fungus isolated from mushroom compost, is described as Thielavia thermophila sp. nov. Its asexual state is a Sporotrichum, resembling S. thermophile Apinis.
Low temperature requirement for saprophytic flax rust cultures
Authors: Turel Franziska L. M.
Published: September 2008

Melampsora lini (Pers.) Lév., races Nos. 3 and 210, grow better at 16 °C than at 17–17.5 °C. Mycelial cultures of race No. 3 were seriously damaged and most of them stopped growing altogether after being kept at 24 °C for 30 to 45 min for transfer.
Effect of ultrasonics on the germination of wild rice (Zizania aquatica)
Authors: Halstead E. H. , Vicario B. T.
Published: September 2008

Seeds of Zizania aquatica which had been afterripened for a period of 90 days at 1–3 °C remained dormant. Treatment of afterripened seeds with ultrasonic vibrations at 70 kc/s for 10 minutes showed a germination count of 74%. Increasing either the intensity or duration of treatment resulted in lower germination. Warm water treatment of dormant seeds resulted in improved germination for some treatments. Exposure in water at a temperature of 45 °C for 240 minutes resulted in a germination of 71%. Treatment with varying ratios of ethanol to water gave only small improvements in seed germination.
An unusual photonastism induced by drought in Phaseolus vulgaris
Authors: Dubetz S.
Published: September 2008

The leaves of bush beans, Phaseolus vulgaris, under conditions of extreme drought and intense sunlight oriented themselves parallel to the incident light and followed the course of the sun in this position. By early morning the leaves assumed relatively normal positions.
Histological studies on the genus Fucus. IV. Regeneration and adventive embryony
Authors: Fulcher R. Gary , McCully Margaret E.
Published: September 2008

Regeneration in Fucus vesiculosus L., both under natural conditions and in culture, has been studied histologically.Cut segments of vegetative tissue from mature Fucus specimens were cultured in seawater. Histological sections of this material were prepared at various intervals up to 8 months of culture to follow the development of adventitious branches from the wound surfaces. In both cultured segments and whole, naturally wounded plants, existing filament and cortical cells in the midrib region of wound surfaces differentiate a new epidermis. Several loci on this new epidermis undergo increased rates of periclinal division to produce structures which are morphologically very similar to normal Fucus embryos and which ultimately acquire apical grooves and apical cells and become flattened in the manner of normal vegetative thallus branches. The significance of the wound-healing process and the formation of adventive embryos is discussed.
Paleobotany of a wild rice lake in Minnesota
Authors: McAndrews John H.
Published: September 2008

Four pollen zones are present in a 360-cm core of sediment from Rice Lake, Becker County. The zones indicate a vegetation succession from mid-postglacial oak savanna to deciduous forest to pine-hardwood forest to an uppermost ragweed zone representing postsettlement forest disturbance. Seeds of wild rice occur in the upper meter of the core with abundant wild rice type pollen. The initial increase of wild rice type pollen is radiocarbon dated at 2450 ± 100 years ago. The ragweed pollen rise that dates land settlement about 75 years ago is radiocarbon dated at 590 ± 95 years ago. The difference is attributed to contamination by dead carbon, and when this error is subtracted from the older date, the corrected age for the spread of wild rice across the lake is 1935 ± 100 radiocarbon years ago.An extensive stand of wild rice at this lake predates by 1000 years prehistoric cultures known to have used wild rice in Minnesota.The spread of wild rice is probably due to either climatic change and associated changes in water quality or to shallowing of the lake by sedimentation, or both factors.
Influences of sweet-fern on germination, survival, and early growth of red pine
Authors: Fraser J. W.
Published: September 2008

Concentrated water extracts from foliage and from roots of sweet-fern were used as moistening media in laboratory tests on germination and survival of red pine. Neither inhibited germination, but both affected survival adversely. In tests simulating field conditions germination, survival, and growth were judged to be more closely related to moisture than to the presence of sweet-fern.
Mucorales isolated from pine root bark and wood
Authors: Kuhlman E. G.
Published: September 2008

Thirty species of Mucorales were recovered in isolations of organisms associated with Fomes annosus and other wood-rotting fungi in decay of Pinus taeda and P. elliottii var. elliottii root bark and wood. Fifteen to 20% of the isolates from roots in advanced decay were Mucorales. Mortierella spp. were most abundant; some of them are described.
Differential effect of 2-chloroethylphosphonic acid on light- and dark-grown tall and dwarf peas
Authors: Thomas D. des S. , Benedict W. G.
Published: September 2008

Tall (Alaska) and dwarf (Progress No. 9 and Early June) peas, Pisum sativum L., grown in the light showed a differential elongation response to 2-chloroethylphosphonic acid (CEPA), only the tall plants being inhibited. CEPA was applied either during seed imbibition or in a postemergence spray. In darkness, CEPA inhibited growth of both tall and dwarf peas, especially the former.
Hepaticae of southwestern Alberta
Authors: Bird C. D. , Hong Won Shic
Published: September 2008

Twenty-two families, 37 genera, and 82 species of Hepaticae are reported from a 13 400 km2 area in the mountains and foothills of southwestern Alberta. The distribution and habitats occupied by each of the species are described. The following distributional elements are represented: Arctic–Boreal, 43%; Pan North American, 33%; Boreal, 20%; Eastern Boreal, 1%; Cordilleran, 1%; and Temperate, 1%. Only one of the species is endemic to North America.
A taximetric study of Vaccinium in northeastern Ontario
Authors: Smith D. W.
Published: September 2008

A study of the population characteristics of wild blueberries in northeastern Ontario was completed using techniques of numerical taxonomy. Forty-five characters were determined on samples of Vaccinium populations from three locations. Analyses of these samples involved (1) the estimation of similarity among individual specimens by the calculation of "taxonomic distance" and (2) the preparation of hierarchic dendrograms. On the dendrogram for each collection two phenon levels were selected, (1) a value of 8.5 for the similarity coefficient to indicate species and (2) a value of 8.8 for the similarity coefficient to indicate variety.The major population components, V. myrtilloides Michx. and V. angustifolium Ait., were separated below a phenon level of 8.5 in all samples. V. myrtilloides exhibited less polymorphism and, in addition, showed distinct differences in phenological characters in comparison to V. angustifolium. Populations of V. angustifolium showed considerable polymorphism, part of which was referable to the characteristics of the varieties and forms described within this species.Specimens recognized as V. boreale Hall and Aalders (the diploid relative of V. angustifolium) were not separated from V. angustifolium at the species level. Also, the variety known as V. angustifolium var. nigrum (Wood) Dole was not separated from V. angustifolium at the rank of variety. In contrast, V. angustifolium var. laevifolium House was found to be a recognizable entity.Specimens recognized as natural hybrids of V. myrtilloides × V. boreale (perhaps also V. angustifolium) were usually separated at a phenon level below that accepted for specific rank. The numerical method appeared to be particularly useful in the separation of these hybrids.
Influence of moisture supply, temperature, and light on frost-hardiness changes in Douglas-fir seedlings
Authors: Driessche R. Van Den
Published: September 2008

Effects of moisture supply, temperature regime, and light on frost-hardiness changes in 2-year-old Douglas-fir seedlings were studied. Frost-hardiness was measured by an electrolytic method. Eight-hour light (3000 ft-c) periods caused increase in hardiness, compared with 16-hour light periods, when seedlings grew under a 12-hour day/night temperature regime of 13 °C/7.5 °C. Long days retarded development of hardiness, under otherwise natural conditions in autumn, but did not prevent plants becoming frost-hardy later. Moisture supply had no direct effect on hardiness, although low supply may have reduced response to photoperiod. Development of hardiness was dependent on night temperature when day and night temperatures were in the range 7.5°–24 °C, and lower night temperatures favored hardening. Loss of hardiness was not influenced by photoperiod.Seedlings did not harden in darkness at 2.5 °C over 9 weeks, but hardening occurred if low intensity light (40 or 100 ft-c) was provided. Continuous low-intensity light caused more hardening than 8-hour light periods, and 100 ft-c caused more hardening than 40 ft-c. An exception was that seedlings previously exposed to 16-hour high-intensity photoperiods showed some ability to harden in darkness.Factors important in development of frost-hardiness were day length, night temperature, and light. Only temperature affected loss of hardiness.
Conidium ontogeny in hyphomycetes. The arthrospores of Oidiodendron and Geotrichum, and the endoarthrospores of Sporendonema
Authors: Cole G. T. , Kendrick W. B.
Published: September 2008

The development of the arthrospores of Oidiodendron and Geotrichum, and the endoarthrospores of Sporendonema, is analyzed by time-lapse photomicrography. The process is not one of exclusively basipetal septation, maturation, and disarticulation, as most previous authors have maintained. The differences between arthrospores and endoarthrospores are seen, in at least one case, to be more profound than has hitherto been suggested. The several ontogenies of arthrospores, endoarthrospores, and meristem arthrospores are differentiated for taxonomic purposes.
Net assimilation rate of wheat as affected by light intensity and temperature
Authors: Friend D. J. C.
Published: September 2008

The net assimilation rate of wheat, on a leaf area basis, declined with time under constant environmental conditions. With continuous illumination at temperatures of 20, 25, and 30 °C, the net assimilation rate increased linearly with increases in the light intensity over the range 200 to 5000 ft-c. The optimal temperature was 15 to 20 °C, and the net assimilation rate declined with increases in temperature over the range 20 to 30 °C. These responses are related to direct effects of light intensity on apparent rates of leaf photosynthesis and to changes in the relative proportion of photosynthetic and primarily respiratory organs under different environmental conditions.
The relative susceptibility of needle- and stem-derived white pine tissue cultures to artificial inoculation with mycelium of Cronartium ribicola
Authors: Harvey A. E. , Grasham J. L.
Published: September 2008

Tissue cultures of Pinus monticola Dougl. derived from stem cortex and leaf tissues were found susceptible to artificial inoculations with mycelium from the blister rust fungus (Cronartium ribicola Fisch. ex Rabenh.). Tissue cultures from leaf mesophyll grew slower and were colonized more rapidly by this fungus than those derived from stem cortex.
Induction expérimentale de fleurs prolifères chez l'Impatiens balsamina variété Buisson fleuri par perturbation de la photopériode
Authors: Debraux G. , Simon L.
Published: September 2008

not available
The effects of carbon dioxide on the growth and development of amphibious plants
Authors: Bristow J. Michael
Published: September 2008

When grown in a stream of 5% CO2 in air on a solid substrate, the heterophyllous amphibious species Ranunculus flabellaris and Myriophyllum brasiliense developed many characteristics of the water form. Plants of the same clones grown in 0.03% CO2 exhibited the land form. Submerged plants grew rapidly when 5% CO2 in air was bubbled through the nutrient medium, and exhibited the typical water form, while plants kept in 0.03% CO2 grew poorly, and the small leaves which developed were intermediate in morphology between the land and water forms. These results are similar to those obtained previously with Marsilea. None of these species were able to utilize bicarbonate. The stream from which the Ranunculus used in the experiments was collected contained high concentrations of dissolved free CO2 during part of the growing season. Thus concentrations of free CO2 higher than those in air may be essential for the normal growth and development of submerged amphibious plants.
Changes in the ribonucleic acid of senescing radish leaves
Authors: Knight R. M. , Quick W. A.
Published: September 2008

Senescing radish leaves, whether attached or detached, exhibited typical downward drifts in total nucleic acid, protein, and chlorophyll, which agreed well with those reported for other species. MAK column profiles of the ribonucleic acid (RNA) from senescing leaves revealed a third peak in the ribosomal region, in addition to the usual heavy and light ribosomal RNA. The new peak eluted before light ribosomal RNA and retained its prominence while the other two diminished in size, suggesting it was a degradation product. The peak was not apparent until the first decreases in total RNA of the leaves signaled the beginning of senescence. No marked changes were observed in the soluble RNA region of the MAK column profile, but an oligonucleotide portion of RNA not retained by the column was prominent in mature leaves. This rapidly diminished in quantity as senescence advanced.
Absence of arginase in healthy and crown gall tissues of tomato
Authors: Manasse Robert
Published: September 2008

The suggestion that changes in arginine levels in crown gall tissue are due to the activity of arginase was investigated in tomato tissue. A semimicro procedure for the assay of arginase activity failed to detect the presence of this enzyme in normal or crown gall tissue.
Gibberellin-like substances in bulb species
Authors: Aung L. H. , Hertogh A. A. De , Staby G. L.
Published: September 2008

The occurrence of gibberellin-like substances in six important bulb species was determined. The results demonstrate the presence of both free and bound GA-like substances in Allium, Hyacinthus, Iris, Lilium, Narcissus, and Tulipa. The possible significance of this class of growth substances in relation to bulb development is discussed.
Interspecific hybridization of the red raspberry and salmonberry
Authors: Virdi B. V. , Eaton G. W.
Published: September 2008

'Newburgh' and 'Willamette' red raspberry cultivars were used as female parents and several U.B.C. Salmonberry clones as pollen parents to produce the first reported hybrids of the two species.
Electrophoretic patterns of soluble fungal proteins and their possible use as taxonomic criteria in the genus Fusarium
Authors: Glynn A. N. , Reid J.
Published: September 2008

Buffer-soluble proteins extracted from 33 isolates of various Fusarium oxysporum formae speciales and 13 other Fusarium species were separated on polyacrylamide gel disc electrophoresis. The resulting patterns were compared and their use as a taxonomic criterion assessed. The results obtained do not support the current concept that this method is useful as a taxonomic tool.
Characterization and classification of mycorrhizae of Douglas fir. I. Pseudotsuga menziesii + Poria terrestris (blue- and orange-staining strains)
Authors: Zak B.
Published: September 2008

Two newly discovered ectotrophic mycorrhizae of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco), each formed by a distinct strain of Poria terrestris (DC. ex Fries) Sacc., are described. Each is named according to tree and fungus species, including strain of the latter as denoted by characteristic staining of respective sporocarps: Pseudotsuga menziesii + Poria terrestris (blue-staining) and P. menziesii + P. terrestris (orange-staining). Macro- and micro-scopic descriptions of the natural mycorrhizae, of surrounding mycelia and rhizomorphs, and of nutrient agar cultures of each fungal strain of P. terrestris are given. The two described strains of Poria terrestris are proposed for at least varietal distinction on the basis of their mycorrhizal and cultural differences.
Dormancy studies in seed of Avena fatua. 6. Germinability of the immature caryopsis
Authors: Andrews C. J. , Simpson G. M.
Published: September 2008

Caryopses of a dormant strain of Avena fatua L. fail to germinate on moist filter paper when immature whereas non-dormant caryopses germinate at 10 days after fertilization and at later stages of development. Embryos of the dormant strain excised at any stage of development fail to germinate in a complex nutrient medium which supports germination and growth of non-dormant embryos at, and after, 10 days following fertilization. Gibberellicacid (GA) promotes germination of dormant caryopses and excised dormant embryos before and at maturity in the presence of either endosperm or the nutrient medium. This requirement for gibberellin is not absolute, since germination of dormant embryos in mid-development occurs when the nutrient medium is solidified with agar in the absence of gibberellin. The stimulatory effect of solidifying the medium is probably due to differential leaching action upon embryos affecting levels of endogenous gibberellins. The genetic source of endosperm does not influence germinability of the embryo, and endosperms of both dormant and non-dormant strains show an increasing capability of supporting postgerminal growth of non-dormant embryos. A block to the use of these nutrients by the embryo, reversible by gibberellin, is present at maturity in endosperm of the dormant strain.
Weight–diameter relationships for 22 woody plant species
Authors: Telfer E. S.
Published: September 2008

Prediction equations are presented for use in estimating total aboveground weight and maximum leaf weight for 22 species of woody plants. Stem diameter at the ground line was found to be closely correlated with both total and leaf weights. This diameter was therefore used in the equations as the measurement from which weights were predicted.
The amino acid composition of TCA-precipitated proteins and of total residues of plant cells grown in suspension culture
Authors: Gamborg Oluf L. , Finlayson A. J.
Published: September 2008

Amino acid analyses were performed on the soluble and total proteins from plant cells grown in suspension culture. The cell cultures originated from 12 different plant species, and the explants were taken from different organs of the plants.Relatively small differences in the amino acid composition existed between the soluble proteins from different species, between cells originating from different organs of the same species, and between the same cultures grown on different media under the same environmental conditions.There was some variation in the proportion of basic, aromatic, and sulfur-containing amino acids which constituted about 17%, 9.5%, and 3% of the protein amino acids, respectively. The amino acid composition of the soluble proteins of wheat coleoptile and soybean hypocotyl resembled that of the soluble proteins from cultured cells of these plants. Essential amino acids, particularly the basic ones and methionine, were proportionally higher in the cell proteins than those reported for seed proteins.
Conspecificity of Plantago fastigiata of North America with P. ovata of the Old World
Authors: Bassett I. J. , Baum B. R.
Published: September 2008

Comparative morphological and palynological studies have been carried out on Plantago fastigiata (P. insularis) of the New World and P. ovata, including some closely allied species of section Leucopsyllium, of the Old World. As a result, P. fastigiata is regarded as conspecific with P. ovata. It is postulated that the North American populations known as P. fastigiata are introductions of P. ovata dating from the late 18th and the beginning of the 19th century by early settlers in California.
Demonstration of a complete Casparian strip in Avena and Ipomoea by a fluorescent staining technique
Authors: Peirson D. R. , Dumbroff E. B.
Published: September 2008

A new combination of embedding material and high contrast stain has provided the means for demonstrating, photographically, tangential sections of endodermal cells showing complete Casparian strips.
Multivesicular structures and cell wall growth
Authors: Fowke L. C. , Setterfield George
Published: September 2008

Applied auxin caused cells of artichoke tuber slices to expand and deposit significant amounts of new wall material while cells in slices held on water remained essentially inert in both respects. Cells in all physiological treatments showed multivesicular structures at the plasma membrane (plasmalemmasomes, lomasomes), within the cytoplasm and within the central vacuoles. The number of plasmalemmasomes was considerably greater in cells not depositing wall than in cells treated with auxin to stimulate wall synthesis. Multivesicular structures showed no relation to Golgi bodies, which increase in number and apparent activity in response to auxin treatment. It is concluded that plasmalemmasomes are not involved in cell wall deposition. Multivesicular structures in plant cells could have several origins and it is suggested that some may represent artifactual reorganization of plasmalemma and tonoplast membranes during cytological processing. Such reorganization would presumably be sensitive to the physiological state of the tissue.
Isolation of a virus inhibitor from plants with localized infections
Authors: Kimmins Warwick C.
Published: September 2008

Systemic resistance was induced in the leaves of Datura stramonium L., Nicotiana glutinosa, Phaseolus vulgaris var. Prince, and Chenopodium amaranticolor by localized infection with tobacco mosaic or necrosis viruses (TMV, TNV). Crude extracts prepared from the resistant leaves were more inhibitory to TNV infection on Phaseolus than were extracts from non-resistant (control) leaves. Subsequently, crude extracts were fractionated into protein and ribonucleic acid (RNA) and inhibitory activity from resistant areas was retained in the RNA preparation. The RNA from resistant and non-resistant leaves was purified and separated into three fractions (about 27 S, 17 S, and 3 S), by gel filtration on Sephadex G-200. The 27-S and 17-S fractions from both treatments inhibited TNV infection by similar amounts. However, the 3-S RNA from resistant leaves reduced lesion number to a greater extent when compared to both the 3-S RNA from control leaves and the 27-S and 17-S RNA from either treatment. The lowest molecular weight RNA isolated from systemic-induced resistant areas gave positive tests with orcinol reagent and had an absorption spectrum characteristic of a nucleic acid. When treated with pancreatic ribonuclease and mixed with TNV, inhibition no longer occurred.
The nucleolus of wheat stem rust uredospores
Authors: Mitchell Stephen , Shaw Michael
Published: September 2008

Electron microscopy shows that the nuclei in immature uredospores of Puccinia graminis tritici possess prominent nucleoli with a mean diameter of 1.7 ± 0.4 μ. The nucleoli in mature uredospores are much smaller (0.5 μ). This reduction in size of the nucleoli may indicate that ribosomal RNA (ribonucleic acid) formation is repressed as uredospores mature.
Embryo sac and early embryo development in the salmonberry (Rubus spectabilis)
Authors: Virdi B. V. , Eaton G. W.
Published: September 2008

Embryo sac development was studied in two clones of salmonberry. U.B.C. clones I-37 and II-4 were used in the study. Clone II-4 is a ruby-fruited seedling of a gold-fruited parent. Clone I-37 is the gold-fruited seedling of a ruby-fruited parent. Reproduction was sexual and embryo development normal in this diploid species. Embryo sac development was of the normal or Polygonum type and abnormalities such as multiple embryo sacs and abbreviated integument were also found. Very generally, the development of embryo sacs in both clones was similar.
Studies on ectomycorrhizae of pine in an electronically air-filtered, air-conditioned, plant-growth room
Authors: Marx Donald H. , Bryan W. Craig
Published: September 2008

An air-filtered, air-conditioned, plant-growth room is described and results of initial studies on ectomycorrhizae of pine in the room are presented. The room was fumigated with methyl bromide and maintained free of airborne spores of ectomycorrhizal fungi for 5 months.In the room, loblolly pine seedlings in pots of soil infested with forest humus developed ectomycorrhizae, whereas several hundred control loblolly pine seedlings did not form ectomycorrhizae. Eleven pine species grown in flats of soil infested with either of two isolates of Thelephora terrestris formed morphologically indistinguishable ectomycorrhizae. Noninoculated seedlings of the same pine species did not form ectomycorrhizae but developed dichotomously branched short roots and root hairs.Outside the room, 90% of loblolly pine seedlings grown in pots developed four different ectomycorrhizal forms, regardless of treatment. The 11 species of pine in flats of initially uninfested soil formed abundant ectomycorrhizae with at least two airborne symbionts, one of which was T. terrestris.Large numbers of pine seedlings with and without specific ectomycorrhizal associations can be studied in other than aseptic culture in the room. In this manner, natural forest conditions can be more closely duplicated for studies on ectomycorrhizal versus nonmycorrhizal relationships.
The morphology and anatomy of holdfasts and branching radicles of Arceuthobium pusillum cultured in vitro
Authors: Bonga J. M.
Published: September 2008

Seeds of the eastern dwarf mistletoe, Arceuthobium pusillum Peck, were cultured on White's medium supplemented with coconut milk, casein hydrolysate, and indoleacetic acid (IAA) or 2,4-dichlorophenoxyacetic acid (2,4-D). Large holdfasts were obtained with 2,4-D. At first, growth of these holdfasts arose from a centrally located meristem, but later from growth centers near the periphery of the holdfasts. Reticulate thickening of the cell walls was observed in the center area of the holdfasts. With IAA, flat structures with branches or papillae were obtained. If the seeds were cultured with 2,4-D for 3 months and then with IAA, a number of holdfasts formed branches. Centers of meristematic activity developed occasionally where radicles and branches were subjected to pressure.
Some new or noteworthy species of the genus Chaetomium
Authors: Udagawa Shun-ichi , Cain Roy F.
Published: September 2008

The following new species are described and illustrated: C. adinocladum, resembling C. cuniculorum generally, but separated by the robust terminal hairs which are gracefully sinuous or loosely curved at their tip and never extend far beyond the mass of delicate, finely branched, fluffy hairs; C. anahelicinum, resembling C. crispatoideum and C. crispatum, in having contorted terminal hairs but producing many regularly coiled branches of the terminal hairs; C. ancistrocladum, a member of the C. murorum group, characterized by large, light brown, ellipsoid ascospores and long, circinate terminal hairs, which are intermingled with shorter, noticeably branched, looped hairs; and C. semispirale, a member of a group having short, spirally coiled terminal hairs, characterized by loosely, 3–4 times coiled, distinctly septate terminal hairs, straight or slightly flexed lateral hairs, dark, lemon-shaped ascospores, and rich orange-colored mass of chlamydospores. Unusual species, C. erraticum and C. subaffine are also redescribed.
The gametophyte and young sporophyte of Ampelopteris prolifera
Authors: Mittra D. , Sen U.
Published: September 2008

The spores of Ampelopteris prolifera (Retz.) Copel. are bilateral and have a smooth exine and a folded perine. The gametophyte arises as a short filament which soon develops into a spatula, and ultimately becomes cordate at maturity. In overcrowded cultures the prothallus is a variously branched filament. Mature gametophytes may develop filamentous or cordate branches. Hairs with extracellular apical cap-like secretions originate both at the margin and on the surfaces of the prothallus. In old prothalli peg-like outgrowths develop on the superficial sides of the wing. The antheridia and archegonia are of the usual type found in the evolutionally advanced ferns. The development of the young sporophyte is described and illustrated. The taxonomic validity of the genus is also discussed.
Nuclear condition and germination characteristics of the aeciosporesof Cronartium comandrae and C. comptoniae
Authors: Powell J. M. , Hiratsuka Y.
Published: September 2008

Two pine stem rusts, Cronartium comandrae Pk. and C. comptoniae Arth., had binucleate mature aeciospores which produced non-septate branched or unbranched germ tubes. No nuclear divisions occurred, and the two nuclei migrated together towards the tip of the germ tube and into an appressorium, if formed. This type of nuclear behavior and germ-tube growth is characteristic of host-alternating races, and distinguishes them from pine-to-pine races. Aeciospores of C. comandrae characteristically produced two or more germ tubes, unlike other pine stem rusts which usually produced one germ tube per spore.
Meiotic studies in Anemone multifida, A. tetonensis, and their hybrids
Authors: Madahar Cecily , Heimburger Margaret
Published: September 2008

Anaphase I was analyzed for bridge and fragment configurations in Anemone multifida vars. multifida, hudsoniana, richardsiana, and saxicola; in intra- and inter-varietal hybrids; in A. tetonenis; and in inter-specific hybrids. Indirect evidence indicated that most bridges and fragments arose from chiasma formation in paracentric inversions rather than from other types of meiotic breakage and reunion events. Variety saxicola differed from other varieties of A. multifida in the low fertility it conferred on its inter-varietal hybrids. Reduced fertility was not due to chromosome structural differences and therefore must reflect other undefined genetic barriers. Hybrids of A. tetonensis with any A. multifida variety tested also had low fertility. This could in large part be accounted for by demonstrated inversion heterozygosity. However, the operation of additional fertility barriers is not excluded.
Unpredicted growth responses of single-ascospore colonies of Neurospora crassa
Authors: Mitchell Mary B.
Published: September 2008

Inheritance of growth characteristics, in two-marker crosses, was studied by comparing samples of ordered spore octets cultured on plates of differently supplemented medium. Two mutants which differ in the timing of their response to thiamine were among those giving unexpected results. Growth of thi-1 from ascospores duplicates that of wild type when thiamine is supplied, but thi-5 is entirely unresponsive during the first 20 h. On yeast extract medium, thi-5 mimics wild type, and conidial transfers from cultures thus established respond to thiamine. Unlike the single mutants, which grow slowly on minimal medium, the thi-1 thi-5 double mutant has an absolute growth requirement. It responds slowly to thiamine plus leucine. Individual wild-type recombinant colonies from thi-1 × thi-5 appear ditype in their response to tryptophan, as if some hyphae were completely inhibited and others unaffected. This condition, and the phenotypic shift characterizing thi-5, suggest unpredicted genetic heterogeneity in mycelia from single ascospores.
Revision of the genus Podospora
Authors: Mirza J. H. , Cain R. F.
Published: September 2008

A key is provided for the 64 recognized species of Podospora. The genus is restricted to species in which the ascospores have an apical germ pore, a basal hyaline cell, and gelatinous appendages. Illustrations are given for 56 species. Detailed descriptions are included for species which are not readily available and the remaining species are briefly described. The following 10 new species found on dung are described and illustrated: P. attoeochaeta from Mexico; P. didyma, Quebec; P. dolichopodalis, Louisiana and Mexico; P. gigantea, Louisiana and Arkansas; P. karachiensis, Pakistan; P. macropodalis, Mexico; P. mexicana, Mexico; P. miniglutinans, Mexico; P. pistilata, Mexico; P. venezuelensis, Venezuela, Mexico, Louisiana, South Pacific. The following new combinations are proposed: P. aloides (Sordaria aloides Fuckel), P. apiculifera (S. apiculifera Speg.), P. argentinensis (S. argentinensis Speg.), P. austro-americana (Hypocopra austro-americana Speg.), P. ellisiana (Pleurage ellisiana Griff.), P. longicollis (Schizothecium longicollis Ames), P. seminuda (Sordaria seminuda Griff.), P. tarvisina (Philocopra tarvisina Sacc.), and P. vesticola (Sphaeria vesticola Berk. & Br.).
Morphological development of an isolate of Schizochytrium aggregatum
Authors: Booth Thomas , Miller Charles E.
Published: September 2008

Morphological development of an isolate of Schizochytrium aggregatum Goldstein and Belsky is presented. This isolate differs in several respects from those originally described. Monads, diads, and tetrads are smaller. Rhizoids may originate from monads as well as diads and tetrads. Variously shaped swellings along the course of the rhizoids and interconnection of one rhizoidal system with another can occur. Monads sometimes function as sporangia.The genus is emended to include the variation of this isolate.
Cyclamen callus culture
Authors: Loewenberg J. R.
Published: September 2008

Cyclamen persicum callus cultures have been established on a defined medium. The tissue requires an auxin and a cytokinin. Adenine, while not required, greatly stimulates growth. The callus grows more vigorously in the dark than in light. After more than 6 years of subculture, the callus retains the capacity to form roots and shoots.
Regulation of enzyme synthesis in aleurone tissue of Avena species
Authors: Naylor J. M.
Published: September 2008

Control of the synthesis of α-amylase in isolated aleurone tissue of an inbred population of wild oats and of the domestic oat variety Torch has been compared. Production of the enzyme in wild oats shows much greater dependence on exogenous gibberellic acid or amino acids than in Torch. It is suggested that this difference reflects variability in a genetic system which determines the degree of hormonal control over the synthesis of hydrolytic enzymes in aleurone of Avena species. Natural selection can be expected to maintain genotypes conferring strong hormonal control of this physiological system in wild oats which depend, for survival, on seed dormancy.
Minimidochium setosum n. gen., n. sp. and Dinemasporium aberrans n. sp. from West Africa
Authors: Sutton B. C.
Published: September 2008

Two new fungi are described from rotting leaves collected in Sierra Leone and Nigeria. Minimidochium setosum n. sp. is typified by superficial, hemispherical, brown, setose sporodochia and unicellular, hyaline, setulate phialospores formed from monophialides. It is compared and contrasted with Mahabalella, Menisporopsis, Colletotrichum, and similar genera. Dinemasporium aberrans n. sp. is characterized by superficial, discoid, brown, setose fructifications and unicellular, lenticular, pale brown, setulate phialospores formed from monophialides. Its relationship with described Dinemasporium species is discussed.
Studies on the anomalous cambial activity in Doxantha unguis-cati (Bignoniaceae). I. Development of the vascular pattern
Authors: Dobbins David R.
Published: September 2008

The development of the vascular pattern was studied in Doxantha unguis-cati as a prelude to correlating the vascular system to the anomalous cambial activity observed in the mature stem. The shoot apex of this liana has a two-layered mantle covering a corpus of a mother cell zone and a flanking meristem. Just below the shoot apex a cylinder of procambium differentiates. The first primary phloem can be recognized in the third internode and the first primary xylem in the fourth or fifth internodes. As the internodes elongate so do the procambial cells. The cells of the pith, on the other hand, are shorter than the procambial cells and accommodate to the extensive internode elongation by cell division. The vascular system of the young shoot includes not only bundles, but also individual strands of phloem. The stem has multilacunar nodes from which five bundles and two phloem strands depart into each of the oppositely paired leaves. Within the stem there are four continuous bundles to which all other bundles connect. The location of these four bundles corresponds to the formation of the characteristic anomalous cambium observed in the secondary growth of the older stem. The relationship between the vascular pattern of D. unguis-cati to other vascular patterns is also discussed.
Verticillium albo-atrum and V. dahliae distinguished by acrylamide gel-electrophoresis of proteins
Authors: Hall R.
Published: September 2008

Buffer-soluble proteins from 10 isolates of Verticillium dahliae and 22 isolates of V. albo-atrum were separated by acrylamide gel-electrophoresis. Isolates within a species produced essentially identical patterns but V. dahliae patterns were distinctly different from those of V. albo-atrum. These results support the view that V. dahliae and V. albo-atrum should be considered as separate species.
Betacyanin accumulation, chlorophyll content, and flower initiation in Chenopodium rubrum as related to endogenous rhythmicity and phytochrome action
Authors: Wagner Edgar , Cumming Bruce G.
Published: September 2008

In Chenopodium rubrum seedlings (ecotypes 50°10′ N and 49°58′ N) betacyanin synthesis is light dependent (completely dark-grown seedlings contain no betacyanin) and is under phytochrome control via both the low energy and the high-energy (HER) reactions of photomorphogenesis. In continuous light, accumulation of betacyanin is linear with time. However, when a single dark period interrupts continuous light, the amount of both betacyanin and chlorophyll synthesized during a given period of time after the dark interruption shows a rhythm reflecting differences in the rate of, and (or) the capacity for, pigment accumulation that are dependent on the duration of the dark period. The rhythm in chlorophyll content was higher in frequency than circadian, with a period of about 15 h, while rhythmicity in the rate of synthesis of betacyanin was circadian. These results suggest that there is endogenous rhythmicity in the metabolic state of the system in darkness. The imposition of light after darkness apparently stabilizes the specific physiological status attained at that respective time of darkness and thus determines the metabolic activity of the seedlings.When glucose was supplied throughout darkness interrupting continuous light, the phasing of the rhythm of betacyanin synthesis was positively correlated with the rhythm of flower initiation, but this was not so when phenylalanine was supplied during darkness. In contrast, when glucose was supplied for a varied length of time in continuous light, there was rhythmicity in the rate of betacyanin accumulation, with a periodicity of about 15 h, that was dependent on the duration of the glucose application.When seedlings were supplied with 10−6 M gibberellic acid during darkness there was a rhythm in the amount of hypocotyl elongation that depended on the length of a single dark period interrupting continuous light. Other evidence has suggested that there is a rhythm in the stability of the cellular membranes; this rhythm was assayed (non-physiologically) by the time of onset of betacyanin leakage from seedlings into an extraction medium and was apparent only after application of 10−10 M gibberellic acid. The rhythms in hypocotyl elongation and in membrane stability that were revealed after the application of gibberellic acid suggest that there may be a rhythm in the rate of differentiation and (or) development of the system.It is postulated that endogenous rhythmicity is due to the spatial separation of energy production and use in different cell particulates, with phytochrome acting as a membrane operator.
The effect of kinetin on the growth of diploid and autotetraploid root tips of rye in vitro
Authors: Yang Da-Ping , Dodson Edward O.
Published: September 2008

Both diploid and autotetraploid root tips of rye, Secale cereale var. Petkus, responded similarly when kinetin and indoleacetic acid (IAA) were added separately to the media in which they were growing. Kinetin retarded the linear growth of the main roots at 1 mg/1 and caused complete inhibition of the initiation of lateral roots; while at 0.1 mg/1, kinetin inhibited the elongation of lateral roots. IAA at 0.1 mg/1 retarded the elongation of main roots, and the initiation and the linear growth of lateral roots. When kinetin and IAA were applied in combination, kinetin was antagonistic to the inhibition caused by a high concentration of IAA in the growth of main roots of tetraploids, but not in the diploid roots.The differential response is considered to be a reflection of their genotypical difference, which may affect the endogenous content or metabolism of these phytohormones of the roots.
Embryo sac and early ovule development in Oryzopsis miliacea and Stipa tortilis
Authors: Maze Jack , Bohm Lesly R. , Mehlenbacher Jr. Lyle E.
Published: September 2008

The ovules of Stipa tortilis and Oryzopsis miliacea are hemianatropous, bitegmetic, and pseudocrassinucellate (sensu Davis 1966). The hemianatropous shape of the ovule is the result of characteristic patterns of cell division and enlargement in the chalazal area and areas alongside the embryo sac. Embryo sac development in both is Polygonum-type and both have proliferating antipodals. Endosperm is nuclear, although in O. miliacea it is atypical in that nuclear division is synchronous within one portion of the embryo sac, e.g. micropylar, but not synchronous between different portions of the embryo sac, e.g., micropylar and chalazal. Differences in ovule initiation, persistence of the outer integument, fate of the inner integument, nature of the nucellus, shape of the embryo sac, nature of the synergids, cytoplasm of the egg, polar nuclei, and endosperm exist between these two taxa. Both synergids of O. miliacea undergo changes before fertilization and one degenerates before fertilization. The pollen tube enters the embryo sac at the base of the persistent synergid. There is presently insufficient embryological data to permit meaningful speculation on relationships between Stipa and Oryzopsis. Embryologically, Stipa and Oryzopsis are festucoid grasses, as much other evidence indicates. Embryo sac development in the Gramineae is more similar to that of the Restionaceae than to that of the Cyperaceae. This is in contradiction to recent speculations on the relationships of the Gramineae.
Root growth studies on Mugho pine
Authors: Mason G. F. , Bhar D. S. , Hilton R. J.
Published: September 2008

Root growth of Mugho pine seedlings was studied in Southern Ontario using a recently constructed rhizotron at the University of Guelph. The investigations have indicated that root growth of this pine in the season following transplanting extends from April to late November. During the summer, average daily root elongation was found to be 6.5 mm in sandy loam and 5.4 mm in organic soils, while during the autumn it was 2.9 and 3.7 mm respectively. Correlations were found to exist between root diameter and rates of root elongation, and suberization. The latter phenomenon began 5 to 7 days after new root growth. In late autumn metacutization occurred. A resinous type of exudate has been observed from the fully suberized roots. Qualitative thin-layer chromatographic studies have shown that the root exudates differed from exudates obtained by wounding pine shoots.
Regeneration on Phycomyces sporangiophores. I. Induction by decapitation and basal cutting on sporangiophores attached to mycelium and after isolation
Authors: Gruen Hans E. , Ootaki Tamotsu
Published: September 2008

Phycomyces blakesleeanus sporangiophores attached to mycelium and isolated sporangiophores cultured on plain agar blocks were decapitated at 1–2 mm below the apex (stage 1) or the top of the sporangium (stages 3, 4). One or more sporangiophore initials regenerated at or very near the wound closure after formation of a cross wall. They emerged only from the side on 82–85% of all parents and on most of the rest from the wound closure wall. Lateral initials frequently perforated the original wall. Regeneration on isolated and attached sporangiophores reached 100% at 12 h on stage 1 and 18 h on stage 3, but only 80% after 24 h on stage 4. The frequency of two or more initials per parent decreased from stage 1 to 4 and was greater on attached than on isolated specimens. Fewer than half of all parents with two initials showed maturation of both. Single sporangiophores elongating on isolated stage 1 parents had a larger diameter, greater stage 1 length, and 66% greater final length than on stage 4. Stage 1 was always very short (average maximum, 5.1 mm). Sporangium formation and maturation were most synchronized after regeneration on stage 1 and least on stage 4.Sporangiophores cut at 5 mm above the base regenerated less frequently than after decapitation and the decrease was larger in stage 4 than in stage 1. Hyphae and sporangiophores regenerated alone or together, but hyphae were most common on attached stage 1 stumps. Regeneration was always from the wound closure wall, and two or more sporangiophore initials per parent were less frequent on stumps than near the apex.Observations on outflowing of drops of cell contents and on wound closure are discussed in relation to regeneration.
Pycnidium production by Botryodiplodia theobromae. III. Germination of pycnidiospores
Authors: Ekundayo J. A.
Published: September 2008

Pycnidiospores of Botryodiplodia theobromae Pat. germinated within 5 h on solid media. The rate and amount of germination in liquid media were lower than on solid media. Near maximum germination occurred over the range 15–42 °C and at 100% relative humidity. Light, which is essential for pycnidium production, had no effect on germination. Five fungicides (Dinocap (Karathane WD), Pano-drench, Bordeaux mixture, Captan, and copper sulphate) commonly applied to fruits, and four potato sprout suppressants (diethylene glycol monobutyl ether, ethylene glycol monobutyl ether, n-amyl and isoamyl alcohol), at concentrations ranging from 0.001% to 2.5%, inhibited germination and germ-tube growth. The potential use of the germination inhibitors as protectants against Botryodiplodia theobromae rot is discussed.
Growth of Cronartium ribicola in the absence of physical contact with its host
Authors: Harvey A. E. , Grasham J. L.
Published: September 2008

Rust mycelia from tissue cultures infected with Cronartium ribicola J. C. Fisch. ex Rabenh. were grown on cellophane membranes in the absence of physical contact with host tissue. These membranes were in contact with agar media containing imbedded, actively growing western white pine (Pinus monticola Dougl.) tissue cultures. Identities of these cultures were verified by reestablishing infections in healthy host tissue cultures.