bluuebunny/crossref_metadata_2025 huggingface dataset:
Computer Simulation of a Sporophytic Self-Incompatibility Breeding System
Authors: Imrie BC , J Kirkman Colleen , Ross DR
Published: July 2016

A sporophytic self� incompatibility system, such as occurs in Carthamus jlavescens Spreng., was studied by computer simulation. Equilibrium gene fre-quencies in an infinite population were estimated for three-allele and six-allele systems and found to be independent of initial frequencies. In a species existing as a series of more or less isolated small populations genetic drift caused rapid loss of alleles. Maintenance of the S allele system was enhanced by increased population size, and particularly by migration, by which alleles lost from one local population could be re-introduced from adjacent populations. Hard seed carryover had a lesser effect.
The Output of Spermatozoa in Rams II. Relationship to Scrotal Circumference, Testis Weight, and the Number of Spermatozoa in Different Parts of the Urogenital Tract
Authors: Lino BF
Published: July 2016

Daily spermatozoan output from the urogenital tract (DSOU), scrotal circumference, testis weight, and the numbers of spermatozoa in the epididymis and other parts of the urogenital tract were measured in 10 rams. Testis weight and the numbers of spermatozoa in the head, body, and tail of the epididymis and in the vas deferens and ampulla were found to be bilaterally symmetrical in each ram. The daily spermatozoan output from the urogenital tract was linearly correlated with testis weight (r = o� 83), with epididymal spermatozoan reserves (r = 0'86), with extragonadal spermatozoan reserves (r = 0�90), and with the total number of spermatozoa in the urogenital tract (r = O� 84). The significance levels of the regression coefficients indicated that these parameters would give good estimates of each other. The total number of spermatozoa in the urogenital tract of all rams at slaughter divided by the predicted time taken for spermatozoa to traverse the tract was found to be approximately 6% below the mean value for the daily spermatozoan output of all rams.
Effects of Some Buffers and Inorganic and Organic Sodium Salts in Synthetic Diluents for the Storage of Ram Spermatozoa At 37 or 5°C
Authors: Lapwood KR , Martin ICA
Published: July 2016

Buffers, inorganic and organic salts, salts of volatile fatty acids, and lyophil-ized non-dialysable skim milk solids were tested in saline-sugar diluents used for storage of ram spermatozoa at 37 and 5�C.
Effects of Composition of Diluent, Method of Addition of Glycerol, Freezing Rate, and Storage Temperature on the Revival of Ram Spermatozoa After Deep-Freezing
Authors: Entwistle KW , Martin ICA
Published: July 2016

The addition of 6% (vJv) egg yolk to a synthetic diluent [247 mM glucose, 49 mM NaCI, 5 mM KCI, 5 mM phosphate buffer, and 7�5% (vJv) glycerol] improved the survival of ram spermatozoa after deep�freezing. Judging by the activity of spermatozoa after thawing, a single addition of glycerol to the diluted semen at 5�C was as effective as multiple additions giving a graded increase of glycerol concentra-tion over a period of 20 min. Reciprocal replacement of the sodium chloride of the diluent by an increase in the concentration of the phosphate buffer showed that motility of the spermatozoa after thawing was depressed when the level of phosphate exceeded 10 mM.
Investigation of Vascular-Streak Dieback of Cocoa in Papua New Guinea
Authors: Keane PJ , Flentje NT , Lamb KP
Published: July 2016

Vasoular�streak diebaok of ooooa in Papua New Guinea has different symptoms from the diseases oommonly referred to as ooooa diebaok in other ooooa�growing oountries. The symptoms of this destruotive disease of ooooa have not previously been reported outside Papua New Guinea. A speoies of tulasnelloid fungus, Oncobasidium theobromae (Talbot & Keane), was oonsistently assooiated with the disease. It grew speoifically within xylem vessels of diseased stems and leaves, preoeding symptom development. It was the only fungus whioh was oonsistently isolated from, and sporulated on, living diseased ooooa stems: it grew from xylem vessels exposed on leaf soars formed by the absoission of diseased leaves and formed white, effused, adherent fruit bodies exolusively on these leaf soars and their adjaoent bark. When spores were shed from these fruit bodies on to expanding leaves of young seedlings, the disease symptoms developed after 3 months and the fungus was re-isolated. o. theobromae therefore appears to be the oause of vasoular-streak diebaok. The fungus did not sporulate in oulture but oonditions neoessary for fruit body formation and sporulation were studied in the field and fluotuations in fruit body numbers were oorrelated with fluotuations in disease inoidenoe.
The Sweat Glands and Hair Follicles of European Cattle
Authors: Mcewan Jenkinson D , Nay T
Published: July 2016

Measurements were made on the skins of 1363 cattle from different European breeds. The mean values of these measurements have been tabulated for each breed and the skin types present in each breed or group of breeds have been determined using sweat gland shape (LID) and hair follicle depth (FrY) as the principal bases of comparison.
Effect of Composition of Tris-Based Diluent and of Thawing Solution on Survival of Ram Spermatozoa Frozen by the Pellet Method
Authors: Salamon S , Visser D
Published: July 2016

Six factorial experiments were conducted to examine the effects of concentra tion of tris(hydroxymethyl)aminomethane (Tris) and type and concentration of sugar in the freezing diluent, and of composition of thawing solution on the survival of ram spermatozoa following the freeze-thaw procedure.
Seasonal Changes in Reproductive Productivity, Growth Rate, and Food Intake in Mice Exposed to Different Regimes of day Length and Environmental Temperature
Authors: R Pennycuik Pamela
Published: July 2016

Groups of mice were maintained in three different environments: (1) constant day length and constant temperature; (2) seasonal fluctuations in day length and constant temperature; (3) seasonal fluctuations in day length and seasonal fluctua-tions in temperature.
Control of Growth in Callitriche Shoots by Growth Retardants and Gibberellic Acid
Authors: Wong CH , JMccomb A
Published: July 2016

Shoots of the aquatic, Callitriche, form floating rosettes of leaves, the internodes of which elongate if the shoot is submerged, or treated at the water surface with gibberellic acid (McComb 1965; Wong and McComb 1967). It may therefore be tentatively proposed that submerged shoots synthesize more gibberellin than do floating shoots. To obtain further information concerning this hypothesis, investiga-tions have been carried out with the growth retardants Amo1618 and CCC, com-pounds which characteristically bring about dwarfing in higher plants, an effect reversed by gibberellin (e.g. McComb and McComb 1970), and which have been shown to inhibit gibberellin biosynthesis in certain systems (e.g. Baldev, Lang, and Agatep 1965; Dennis, Upper, and West 1965; Zeevaart 1966).
Accumulation of Dry Matter and Nitrogen by Grains in Different Positions of the Wheat Ear as Influenced by Shading and Defoliation
Authors: Bremner PM
Published: July 2016

The order of priority for supply of assimilate and nitrogen between individual grains of the wheat ear was studied by determining their accumulation of dry matter and nitrogen when the supply was varied by shading and defoliation, alone and combined, from 2 weeks after anthesis.
A Model of the Extension and Branching of a Seminal Root of Barley, and Its Use in Studying Relations Between Root Dimensions I. the Model
Authors: Hackett C , Rose DA
Published: July 2016

Previous papers have reported that relations between the total number, length, surface area, and volume of graminaceous root members tend to remain roughly constant during vegetative growth. Through the use of a model of the extension and branching of a seminal root of barley (Hordeum vulgare L.), which was developed for the purpose, an attempt has now been made to determine the properties of root growth responsible for the phenomenon.
Organ Regeneration on Excised Roots of Chondrilla Juncea and Its Chemical Regulation
Authors: Kefford NP , Caso OH
Published: July 2016

The effects of endogenous factors (plant age, section length, and section location) and environmental factors (temperature and mineral nutrition) upon organ regeneration on isolated root sections of Ohondrilla juncea L. were used to develop a standard assay system for the study of the chemical regulation of regeneration. Bud and root formation and its polarity in the presence of a variety of regulators alone and in combinations were observed quantitatively. Bud numbers were increased by auxin (low concentrations), cytokinin, and gibberellin treatments. High concentra� tions of auxin inhibited bud formation and this effect was reversed by antiauxin, cytokinin, or gibberellin. Adenine did not counteract auxin� induced bud inhibition but adenine and N�6�benzyladenine did counteract inhibition induced by the purine antagonist 2,6�diaminopurine. Numbers of regenerated roots were increased by auxin treatment and reduced by cytokinin and gibberellin treatment. On control and auxin� treated sections, bud formation was strongly polar and proximal and cytokinin and gibberellin treatments lessened the polarity. Growth retardants inhibited regeneration. Of a number of synthetic auxins tested, 2,4.dichlorophenoxy. acet.O.methylhydroxamic acid and 4�amino.3,5,6.trichloropicolinic acid were the most effective inhibitors of bud formation.
Cytogenetical Studies in Wheat VI. Chromosome Location and Linkage Studies Involving Sr13 and Sr8 for Reaction to Puccinia Graminis F. Sp. Tritici
Authors: Mcintosh RA
Published: July 2016

Sr 13 was located on the fl arm of chromosome 6A and showed a recombination value of 0�54�0�07 with the centromere. Sr8 was localized to the opposite (tt) arm and exhibited a recombination value of 0�44 � 0�05 with the centromere. Genetic independence between Sr13 and Sr8 was confirmed in a genetic study involving a cross between two near.isogenic lines, each carrying one of the genes.
Action Spectrum for the Opening of Albizia Julibrissin Pinnules, and the Role of Phytochrome in the Closing Movements of Pinnules and of Stomata of Vicla Faba
Authors: Evans LT , Allaway WG
Published: July 2016

The opening movements of both V. faha stomata and A. julibris8in pinnules have been shown previously to depend on a redistribution of potassium ions under the influence of light. Action spectra for both systems show peak effectiveness in blue light, at 440 nm, but for pinnule opening in A. julibri88in there is a subsidiary peak in the far red (720 nm). However, opening in far red shows an initial lag period, whereas opening in blue light is rapid. The action spectrum for pinnule opening was not influenced by leaf age, the presence or absence of CO2, or by simultaneous red light.
Uptake and Transport of Ions in Barley Seedlings III. Correlation Between Transport to the Shoot and Relative Growth Rate
Authors: Pitman MG
Published: July 2016

Determinations of potassium transport are described for plants growing at varied relative growth rates. These determinations were based on differences in total potassium content of the shoot over a 3.day period for plants growing on culture solution. It is shown that rate of transport from root to shoot is correlated with relative growth rate. The concentration of potassium in the shoot was independent of ratio of root to shoot, and little affected by relative growth rate (potassium was the only available univalent cation).
Permeability of the Duodenum of the Toad to Non-Electrolytes
Authors: Tay DKC , Findlay GP
Published: July 2016

The reflection coefficients (0") for the permeation, from serosa to mucosa, of 59 different non-electrolytes through the duodenum of the toad have been measured by the method used by Diamond and Wright (1969a) with the rabbit gall bladder. In this method 0" for the solute is the ratio of the streaming potential across the epithelium, resulting from a water flow caused by an osmotic gradient of the test solute, to the streaming potential caused by water flow resulting from an equal osmotic gradient of impermeant solute.
Effect of Osmolality and Phosphate, 'Tris', 'Tes', 'Mes', and 'Hepes' Hydrogen Ion Buffers on the Motility of Bull Spermatozoa Stored At 37 Or 5°C
Authors: Jones RC , Foote RH
Published: July 2016

Bull spermatozoa survived incubation, in unstoppered tubes at 5 and 37�C, better in solutions of 250 m-05molesJkg than in solutions of higher or lower osmolali-ties regardless of the concentrations of sodium chloride or citrate in the solutions relative to the concentrations of phosphate, Tris, TES, MES, or HEPES. When buffer solutions contributed 120 m-osmolesJkg to a total diluent strength of 250 m-osmolesJkg, the ranking from best to worst on the basis of survival of spermatozoa was: MES, HEPES, TES, Tris, and phosphate. Comparisons when 50 mM con-centrations of the buffers were used showed the same ranking except that HEPES was as good as.MES.
Sulphur Metabolism and Excretion Studies in Ruminants IX. Sulphur, Nitrogen, and Energy Utilization by Sheep Fed a Sulphur-Deficient and a Sulphate-Supplemented, Roughage-Based Diet
Authors: Bird PR
Published: July 2016

Four Merino wethers were each fed a sulphur-deficient, roughage-based ration containing 1'05% nitrogen (79% as urea) and supplying 135 mg sulphur/day. Four other sheep were fed similar amounts of basal ration supplemented with NasS04. This ration supplied 494 mg sulphur/day. Mter 21-day periods the treatment groups were reversed.
Photosynthesis of Tropical Pasture Plantsiv. Basis and Consequences of Differences Between Grasses and Legumes
Authors: M Ludlow M , Wilson GL
Published: July 2016

Differences in leaf net photosynthetic rate were associated with differences in intracellular resistance. The larger intracellular resistance of legume leaves appeared to result from larger resistances to the movement of C02 from the mesophyll cell wall to the photosynthetic sites rather than from high resistances associated with its fixation at the sites.
A Method of Applying Nutrients Locally to Roots Under Controlled Conditions, and Some Morphological Effects of Locally Applied Nitrate on the Branching of Wheat Roots
Authors: Hackett C
Published: July 2016

A method has been developed for examining the effect of locally applied ions on the initiation and early extension growth of first-order laterals of wheat roots. Features of the method are the avoidance of sealing, flexibility in the positioning of treatments, and freedom to examine the root systems during growth.
The Chemical Composition of Wool X. Material Digested by Trypsin From Fibres and Cortical Cells
Authors: Peters DE , Bradbury JH
Published: July 2016

Samples of wool, wool pretreated with formic acid, and cortical cells produced by mechanical agitation in formic acid have been digested by trypsin. The evidence shows that the formic acid treatment is not degradative. It is found by electron microscopy that trypsin digests the endocuticle, part of the cell membrane complex, and the nuclear remnants and intermacrofibrillar material of the. cortex. These digested components amount to about 3�6, 1� 8, and 12�6% by weight of the fibre respectively.
The Chemical Composition of Wool XI. Separation and Analysis of Exocuticle and Endocuticle
Authors: Bradbury JH , Ley KF
Published: July 2016

Whole cuticle is separated from wool by treatment in formic acid. Digestion of cuticle with pronase is complete after 36% by weight of cuticle is dissolved and the residue is shown by electron microscopy to be exocuticle, with no evidence of adhering endocuticle. The digested protein corresponds to endocuticle and the residue to exocuticle. The endocuticle contains only 3 residues per 100 of !cystine and is generally similar in amino acid analysis to the non-keratinous material from the cortex (Peters and Bradbury 1972).
Effects of Lettuce Mosaic Virus on the Fine Structure of Mesophyll Cells of Chenopodium Quinoa Willd
Authors: Pares RD
Published: July 2016

Although lettuce mosaic virus (LMV) has been studied from many points of view, as summarized by Tomlinson (1970), there has been no published record of the effects of this virus on the fine structure of its host's cells. Edwardson (1966) noted that LMV induced cytoplasmic inclusions in host cells but did not record any effects on organelles. This communication reports the effects of LMV on fine structure of mesophyll cells of C. quinoa.
Thermal Properties of the Collagen of Jellyfish (Aurelia Coerulea) and their Relation to its Thermal Behaviour
Authors: Rigby BJ , Hafey M
Published: July 2016

It has been reported elsewhere (Rigby 1968a, 1968b) that for a number of poikilotherms sudden changes occur in physiological behaviour at temperatures which are the same as the melting temperature of their molecular collagen. A more general statement, which includes the above observations, is that the upper limit of the environmental temperature for an animal corresponds with the melting tempera. ture of its molecular collagen. A number of workers have contributed to this idea and details may be found in Rigby (1968a). It is not suggested that collagen is uniquely involved in these events, although this may be so. No doubt other body proteins are altered at the same time. The useful point is that collagen is one of the few easily prepared body proteins with a characteristic melting point, and as such can serve as an indicator in studies concerned with the temperature relation of poikilotherms. For example, animals, which can be adapted to reproduce at higher or lower temperatures than is usual for them, may produce a collagen which shows a parallel alteration in its melting temperature. Such an experiment would afford a test of the general assumption that the constitution and properties of a protein are determined only by genetic coding (see also Ruda1l1968).
Significance of the Orientation of Coordinated Imidazole and Benzimidazole Groups in Haemoprotein and Vitamin B12 Structures
Authors: Fergusson JE , Robinson WT , Rodley GA
Published: July 2016

Details of the structure of the dioxygen complex, Co(bzacen)(py)02 [py = pyridine; bzacen = N,N'-ethylenebis(benzoylacetoniminide), PhC(O-)=CHC-(Me)=NCH2-)2], a possible model compound for oxygenated haemoproteins (RodIey and Robinson 1972), have prompted a study of the metal-ligand bonding in this compound and related biological systems. It has already been noted (RodIey and Robinson 1972) that the orientation of the benzimidazole group in the vitamin B12 structures resembles closely that found for the pyridine plane in Co(bzacen)(py)02 (Fig. 1), and the recently determined structure of ferricytochrome c (Dickerson et al.
Microfibrillar Material From Various Sources of Keratin
Authors: Whitmore PG
Published: July 2016

The elusive keratin microfibril (Rogers 1959; Dobb and Rogers 1967; Dobb, Sikorski, and Whitmore 1968; Millward 1969) has been observed in an almost native form. in dispersions of enzyme-treated rat vibrissal follicles (Whitmore 1972). It is now evident that similar filaments can be readily obtained by dispersing other enzyme-treated keratins.
A Scanning Electron Microscope Study of the Morphology of Rhinoceros Horn
Authors: Lynch LJ , Robinson V , Anderson CA
Published: July 2016

The morphology of rhinoceros horn as revealed by the scanning electron microscope is reported. The results are broadly consistent with previous studies of the material. Two different-shaped cortical cell units are shown to exist.
Zea Mays: Methods for Diploid Callus Culture and the Subsequent Differentiation of Various Plant Structures
Authors: Gresshoff PM , Doy CH
Published: July 2016

A diploid callus line of Z. mays has been established on fully defined media, taking advantage of the callus-forming potential of squashed embryos. This method is general, and thereby not restrictive to one strain or mutant cell line.
Effect of Night Temperature on the Assimilation of Carbon Dioxide by Mature Pineapple Plants, Ananas Comosus (L.) Merr
Authors: Neales TF
Published: July 2016

The influence of a range of ambient night temperatures (15-35�C) on theCO.exchange patterns of mature pineapple plants is described. As night temperatures are increased (with day temperatures held constant at 27� 5�C) the net assimilation of CO. at night decreased, while that by day increased.
Recovery of Potentially Pathogenic Phytophthora and Pythium Spp. From Native Vegetation in Australia
Authors: Pratt BH , Heather WA
Published: July 2016

Soil and plant root samples from a variety of native forest habitats throughout Australia were examined for potentially pathogenic Pythium and Phytophthora spp. by lupin baiting.
The Effect of Ultrasonic Irradiation on Proteins
Authors: O'shea JM , Bradbury JH
Published: July 2016

Myoglobin, apomyoglobin, S-carboxymethyl bovine serum albumin, soluble S-carboxymethyl high-sulphur (SCMKB) and low-sulphur (SCMKA) proteins from wool, and also insoluble wool fibres have been subjected to ultrasonic irradiation in formic acid and the modified proteins studied by gel-permeation chromatography and other methods.
Haemoglobin Polymorphisms in the Echidna, Tachyglossus Aculeatus
Authors: Cooper DW , Vandeberg JL , Griffiths ME , HM Ealey E
Published: July 2016

Echidnas and platypuses possess two haemoglobins, HbI and HbII. HbI is in the higher concentration. Genetic variation has been found in the electrophoretic mobility of both HbI and HbII in the echidna.
Plasma Amino Acid Patterns in Sheep Receiving Abomasal Infusions of Methionine and Cystine
Authors: Reis PJ , Tunks DA , Sharry LF
Published: July 2016

Plasma amino acid patterns were studied in sheep receiving varying amounts of DL- or L-methionine (0'6-10�0 g/day) or L-cystine (2�0 and 8�0 g/day) as abomasal supplements or DL-methionine (10 g/day) as a dietary supplement.
Peroxidase Activity and Lignification in the Pod Membrane of Pisum Sativum L.
Authors: C Bowling Alison , Crowden RK
Published: July 2016

An investigation of four mutant genotypes of P. sativum has shown an inverse relationship between peroxidase activity and lignification of the pod membrane. From developmental studies, it appears that the main role of peroxidase is in cellular growth and differentiation.
The Uterus of the Ewe II. Chemical Analysis of Uterine Fluid Collected by Cannulation
Authors: Wales RG
Published: July 2016

The chemical composition of uterine fluid collected from ewes cannulated by three different procedures was studied.
Electron Probe Microanalysis of Potassium and Chloride in Freeze-Substituted Leaf Sections of Zea Mays
Authors: Pallaghy CK
Published: July 2016

Small sections of leaves were floated on distilled water under either light or dark conditions, and were freeze-substituted in a 1 % solution of osmium tetroxide in acetone at -78�C followed by embedding in an epoxy resin. Approximately I-11m-thick sections were cut using a dry diamond knife and examined by scanning transmission electron microscopy. The relative concentrations of potassium and chloride in subcellular compartments were determined using an energy dispersive X-ray analyser. The concentration of sodium in the leaf (1�7 m-equivjkg of wet tissue) was too low to be detected by this method. The spatial resolution of this technique was sufficient to distinguish between concentrations in the chloroplasts, cytoplasm, vacuole, and nuclei. The concentration of chloride in stomata and some other epidermal cells was very much higher than in either mesophyll or bundle sheath cells. The potassium concentration in some vascular cells was at least two- to threefold higher than that in mesophyll or bundle sheath cells. The Cl : K ratio in mesophyll and bundle sheath cells resembled that in the solution (0 �10) used for growing the plants. The concentration of chloride in the "free" cytoplasm of mesophyll cells was always very low. Significant differences were found in the "ion" relations of mesophyll and bundle sheath cells. Whereas the ratio of potassium concentration between the vacuole and chloroplasts of mesophyll cells was high (1 �19) in the light and low (0�65) in the dark, the opposite was true for bundle sheath cells-O� 65 and 0�86 respectively. The ratio of potassium concentration between the vacuo les of mesophyll and those of bundle sheath cells was 1 �48 in the light, but only 0�76 in the dark. These concentration gradients are discussed in relation to a possible transfer of organic acid salts of potassium between these two cell types.
Linkage of Genes for Reaction to Puccinia Graminis F. Sp. Tritici and p. Recondita in Selkirk Wheat and Related Cultivars
Authors: Mcintosh RA , Luig NH
Published: July 2016

A previously unidentified gene, Sr23, for resistance to P. graminis in wheat cultivars Selkirk, Exchange, Warden, and possibly Etoile de Choisy is reported. Sr23, which is involved in a necrotic infection type, is closely linked ( <: 0�7 % recombination at P = 0�05) in coupling with Lr16 for resistance to P. recondita which is located in chromosome 4A.
Some Organochlorine Pesticide Residues in Wildlife of the Northern Territory, Australia, 1970-71
Authors: M Best Susan
Published: July 2016

A survey was made, during 1970 and 1971, of organochlorine pesticide residues in the fatty tissues of 12 mammal, 4 bird, 10 reptile, and 6 fish species collected from areas defined as undeveloped and developed of both the arid and tropical zones of the Northern Territory. Pooled samples were taken of most species. Where possible, each species was sampled from each of the four areas.
Effect of Feefing Protected Lipid on the Uptake of Precursors of Milk Fat by the Bovine Mammary Gland
Authors: Gooden JM , Lascelles AK
Published: July 2016

The feeding of protected lipid to lactating dairy cows resulted in a substantial increase in the proportion of fatty acid 18:2 and a decrease in fatty acids 4:0 to 16:0 in milk fat.
Coagulant and Non-Coagulant Fixation of Plant Cells
Authors: O'brien TP , Kuo J , E Mccully M , Zee S-Y
Published: July 2016

The appearance of cells from the meristem of the root tip of Phaseolus vulgaris after fixation in a variety of coagulant and non-coagulant fixatives is described and illustrated by correlated light and electron microscopy. The action of these same fixatives and some of their components upon the living cells of the petiolar hairs of Heracleum mantegazzianum is then described. Glutaraldehyde emerged as an excellent fixative for general use from these studies and further tests show that it will stabilize Hecht's threads in plasmolysed onion epidermis against breakage during dehydration. However, the formation of rounded cytoplasmic vacuoles from a pre-existing set of canalicular vacuoles and transformations of the cell membrane and tonoplasts were noted during these studies and none of the fixatives tested prevent the formation of these artefacts.
Effect of Light on the Volume and Ion Relations of Chloroplasts in Detached Leaves of Elodea Densa
Authors: De Fillippis LF , Pallaghy CK
Published: July 2016

Light-induced changes in chloroplasts of detached leaves of E. densa were investigated either by fixing leaves in 6% glutaraldehyde or by snap-freezing leaves and isolating chloroplasts after freeze-substitution in acetone. Individual chloroplasts were examined by electron probe analysis.
Effect of Mixing and Sieving on Incidence of Gaeumannomyces Graminis Var. Tritici in Field Soil
Authors: Mac Nish GC
Published: July 2016

A bioassay was employed to compare the effect of various treatments on the level of G. graminis var. tritici inoculum in soil cores taken from a take-all patch. In a comparison of undisturbed soil and mixed soil, mixing caused a small reduction in incidence, possibly due to a dilution of the inoculum in the surface soil. Graded degrees of sieving from 5 to O� 5 mm mesh size caused a significant reduction in inoculum levels, with the latter reducing incidence to 3 % in seedlings at 4 weeks. However, it was also shown that increasingly finer sieving caused an increase in disease incidence if the seedlings were allowed to grow to maturity. It was not established whether the sieving affected the soil in such a way as to favour the pathogen, lower the resistance of the plant, or both.
Detection of Gaeumannomyces Graminis Var. Tritici in Wheat Stubble
Authors: Mac Nish GC
Published: July 2016

Two methods (visual assessment and a bioassay) of detecting the presence of G. graminis var. tritici in wheat stubble were compared. Of the stubble visually assessed as infected, only 4 % was not confirmed as infected by the bioassay. On the other hand, the bioassay showed that 41 % of the stubble visually assessed as free of infection was incorrectly assigned.
Relation Between Incidence of Gaeumannomyces Graminis Var. Tritlci and Grain Yield
Authors: Mac Nish GC , Dodman RL
Published: July 2016

A method of using grain yield to estimate the incidence of G. graminis var. tritici in the field is described. It was found that a map based on yield alone underestimated the actual incidence. However, when incidence and grain yield were coupled by the use of an "incidence-yield" regression established on a few sites, a map showing estimated levels of G. graminis var. tritici was obtained without destroying the experimental area. Bioassays of stubble and of soil cores were used to establish the actual incidence of G. graminis var. tritici; the former gave better results.
The Storage of Fertilized Sheep Ova At 5°C
Authors: Moore NW , Bilton RJ
Published: July 2016

Fertilized day-2 (1-4 cells) and day-5 (morulae) sheep ova were cooled at a rate of 0�25 or 1�0 degC/min to 5�C then stored at 5�C for intervals between 10 min and 6 hr, after which they were cultured in vitro for two days at 37� 5�C. Storage had no effect upon subsequent development in culture. Of 103 day-2 ova, 75 (73 %) developed to eight cells and 57 of 88 (65 %) day-5 ova developed to blastocysts. There were no effects of age of ovum, cooling rate, or duration of storage on development in culture.
Correlated Responses of Different scute Genotypes to Long-term Selection for Increased Abdominal Bristle Number in Drosophila melanogaster
Authors: Yoo BH
Published: July 2016

The first dose effect of sc+ has been measured for abdominal bristle number in six replicate lines of D. melanogaster being selected upward for this character in the sc homo-and hemizygote. The within-line regression coefficient of the heterozygote on the sc homozygote showed considerable variation among the lines with a range of 0-47-1' 22, indicating the dependence of gene action on genetic background. But, on the average, the effect of sc+ was approximately additive for abdominal bristle number. From this average, the genetic correlation in the base population between the two genotypes was estimated to be considerably less than unity, which suggests some genetic variability that is dependent on the genotype of the major locus. A similar relationship was also obtained for the two male hemizygotes.
Delay in the Onset of Thermal Tachypnoea in Shorn Sheep Exposed to 42°C in Winter and Summer
Authors: Maskrey M
Published: July 2016

Shorn sheep were routinely exposed to ambient temperatures (Ta) of 14 and 42�C in a climatic chamber in winter and in summer. Rectal temperature (Tre) and skin temperature (Tsk) were measured at 14�C and the time elapsing between raising the Ta to 42�C and the onset of thermal tachypnoea was recorded. It was found that the onset of thermal tachypnoea in the heat was dependent upon the Ta to which the sheep had been previously exposed in the animal house and, in summer, the degree of fleece regrowth. There was an inverse linear relationship between the mean Tsk recorded immediately prior to raising the Ta and the delay in onset of thermal tachypnoea both in winter and summer. Thus, for either season, the inhibition of panting could be related to the degree of cold stimulation received from the periphery. However, a comparison of winter and summer data indicated that other factors were also involved. Tsk was significantly higher, and Tre significantly lower, in winter than in summer. These observations point towards possible seasonal changes in basal metabolic rate and thermoregulatory set-points. The results are discussed with regard to current theories concerning the mechanisms leading to the inhibition of thermal tachypnoea in shorn sheep.
Inositol Phosphate Phosphatases of Microbiological Origin. Some Properties of the Partially Purified Phosphatases of Aspergillus ficuum NRRL 3135
Authors: Irving GCJ , Cosgrove DJ
Published: July 2016

Partially purified samples of the acid phosphatase (EC 3.1.3.2) and of the phytase (EC 3.1.3.8) from A. ficuum were prepared by gel-filtration and ion-exchange dextran chromatography.
Fertility following Inseminations with Frozen-Thawed Reconcentrated and Unconcentrated Ram Semen
Authors: Visser D , Salamon S
Published: July 2016

Fertility results are presented for ram semen that was pellet-frozen in tris-glucose-yolk-g1ycerol diluent. Lambing following insemination with concentrated and unconcentrated inseminates was 35�0% (49/140) and 38�6% (56/145) respectively. Increasing the number of motile spermatozoa and double insemination improved the fertility.
Behaviour of Two-sex Groups of Mice at 4, 21 and 33°C
Authors: R Pennycuik Pamela
Published: July 2016

Groups of mice comprising two males only, two males plus two females, two males plus six females, or two males plus 14 females were housed in pens at 4, 21 or 33�C. The pens were partitioned into two territories connected by a small hole and each subdivision was equipped with two box shelters on either side of an open area containing food, water and woodwool.
Attempts to Produce Identical Offspring in the Sheep by Mechanical Division of the Ovum
Authors: Trounson AO , Moore NW
Published: July 2016

In an attempt to produce identical offspring artificially, the inner cell mass of ova, collected on days 4, 6 and 7 after oestrus (day 0 = day of oestrus), was mechanically divided into two equal sections. The sections were then either cultured in vitro for 2 days and the resulting apparently normal blasto-cysts transferred to recipient ewes or, in the case of day-7 ova, transferred to recipient ewes without a period of in vitro culture.
Effect of Progesterone and Oestrogen on the Survival and Development of Fertilized Ova in the Ovariectomized Ewe
Authors: Trounson AO , Moore NW
Published: July 2016

Two experiments were carried out to investigate the importance of progesterone and oestrogen for the survival and development of fertilized ova in ovariectomized ewes. In experiment 1 ewes were treated with progesterone (P) alone or progesterone and 17 p-oestradiol (P + E2) following ovariectomy on the second (day 2) or sixth day (day 6) after mating to vasectomized rams. Fertilized ova were transferred to the ewes either immediately after ovariectomy or on day 6 after ovariectomy on day 2. In experi-ment 2 ewes that had been given an equine anterior pituitary extract to induce multiple ovulation were ovariectomized on day 2 after mating to fertile rams, and then treated with P or P+E2. On day 18 the uteri of all ewes were flushed to recover embryos. Treatment with P commenced immediately after ovariectomy and E2 was given from day 21-to day 5, to ewes ovariectomized on day 2. Ovarian vein blood was collected just prior to ovariectomy and was assayed for its progesterone and oestrogen contents.
Further Studies on the Accumulation of Energy Substrates by Two-cell Mouse Embryos
Authors: Wales RG , Whittingham DG
Published: July 2016

The accumulation of substrate carbon by two-cell mouse embryos after incubation for 30 min in isotopically labelled substrates was compared by two different methods. The embryos were centri-fuged either through an isotonic sucrose solution to free them from radioactive medium before coun-ting or in radioactive medium in a capillary tube when substrate uptake was calculated from the relative counts in packed embryos and incubation medium.
The Maintenance of Alcohol Dehydrogenase Polymorphism in Bromus mollis L.
Authors: Brown AHD , Marshall DR , lbrecht LA
Published: July 2016

Microgeographic differentiation was studied in a natural population of soft bromegrass (B. mollis) located in an environment that was conspicuously variable for soil moisture. In particular, we examined the effect of this environmental variable on the distribution of alleles that specified electro-phoreticaIIy distinct forms, or aIIozymes, of alcohol dehydrogenase (EC 1.1.1.1). The major features of subpopulation structure found were (1) phenotypic differentiation among sites for measurement characters, (2) a consistent and large difference in plant height between wet and dry sites, (3) no significant differentiation for alcohol dehydrogenase aIIozyme frequencies, (4) substantial differences in allozyme frequencies at three other loci affecting enzymes that are apparently unrelated to anaerobiosis, (5) higher levels of outcrossing in the wetter sites, and (6) an excess of heterozygotes at each of the six aIIozyme loci, but this excess was restricted to the dry sites. These findings are discussed in relation to the problem of determining selective forces which act on individual aIIozyme variants, and which, because of the coherent genetic system in this species, may be confounded with other modes of selection.
The Macroheterogeneity of Type I Tyrosine-rich Proteins of Merino Wool
Authors: M Gillespie J , Frenkel MJ
Published: July 2016

The cystine-poor family of tyrosine-rich proteins of wool as their S-carboxymethyl derivatives has been shown by chromatography on quaternary ammonium ethylcellulose (QAE-cellulose) at pH 10� 5 to consist of 10 groups of proteins which span a threefold range of tyrosine content and vary in many other amino acids, particularly S-carboxymethylcysteine. Electrophoresis at pH 8�9 revealed that most fractions contain two or more components and by further chromatography of five of these groups at pH 8�3 on DEAE-cellulose 10 components have been isolated. The amino acid composition suggests that the components within each QAE-cellulose group are very closely related.
The Liver as the Site of Carnitine Biosynthesis in Sheep with Alloxan-induced Diabetes
Authors: Snoswell AM , Mclntosh GH
Published: July 2016

The total acid-soluble carnitine concentration in the livers of three sheep increased 20-fold, to 4530 nmoljg wet weight, 10-14 days after induction of the diabetic state by alloxan. There was a threefold increase in the total carnitine concentration of the kidney cortex and no significant change in that of heart or skeletal muscle (M. biceps femoris).
The Concentrations of Lipids in the Adrenal Cortical Tissue of Genetically Different Types of Cattle
Authors: O'Kelly JC
Published: July 2016

The concentrations of lipids in the plasma and adrenal cortical tissue were compared in British (Bos taurus) and Zebu (Brahman cross and Africander cross) cattle. Plasma cholesterol and phospho-lipid concentrations were higher (P < 0'001) in Zebu than in British animals. In grazing steers the adrenal cholesterol concentrations were higher (P < 0'01) in Zebu than in British steers but phospholipid concentrations were lower (P < 0'01) in Brahman cross than in Africander cross and British animals. The correlations between the concentrations of cholesterol in plasma and adrenal glands were significant. In Zebu steers on different dietary treatments the concentrations of choles-terol and phospholipid were higher (P < 0'01) and triglyceride lower (P < 0�01) in the adrenal tissue of steers growing normally than of steers losing weight. The adrenal to body weight ratios were lower (P < 0'01) in Brahman cross than in Africander cross and British grazing animals.
Effect of Haemin on Endogenous Protein Synthesis in Oocytes of the Queensland Cane Toad Bufo marinus
Authors: Glenn AR , May BK
Published: July 2016

Although general protein synthesis as measured by L-[3Hlleucine incorporation is unaffected by injection of haemin into oocytes of B. marinus, the synthesis of at least two proteins is repressed. It appears that haemin is capable of exerting inhibitory effects on eukaryote protein synthesis as well as stimulating it as previously reported by other workers.
The Influence of some Fractions of Egg Yolk on the Survival of Ram Spermatozoa at 5oC
Authors: Watson PF , Martin ICA
Published: July 2016

Ram spermatozoa were stored at 5�C in diluents containing various fractions of egg yolk prepared by dialysis, ultrafiltration and ion-exchange chromatography. They survived storage best in the presence of components of egg yolk which were non-dialysable and were not filtered through membranes which retained substances of molecular weight greater than 100000. The substances isolated in peak B of the ion-exchange chromatogram of whole egg yolk described by Seideman et al. (1969) gave greater protection than those from other fractions from this chromatographic system. These data indicate that the low-density lipoprotein fraction of egg yolk is the most likely source of protection to ram spermatozoa against the effects of storage at 5�C.
Cytogenetical Stndies in Wheat. VII Gene Lr23 for Reaction to Puccinia recondita in Gabo and Related Cultivars
Authors: McIntosh RA , Dyck PL
Published: July 2016

Gene Lr23, previously designated LrG, was located on the short arm of chromosome 2B and showed approximately 4 % recombination with the centromere and 22 % recombination with Sr9 which is situated on the long arm. In some crosses Lr23 was recessive whereas in others it was partially dominant. The degree of dominance of Lr23 was greater at higher temperatures. A gene which inhibited the expression of Lr23 under Canadian test conditions acted as a partial inhibitor, or modifier, under Australian test conditions.
Alkaline Phosphatase Mutants of Bacillus subtilis
Authors: RGlenn A
Published: July 2016

Alkaline phosphatases from vegetative and sporulating cells of B. subtilis have been shown previously to be identical in all criteria examined. Despite this, 15 mutants producing low levels of the phosphatase during phosphate starvation of vegetative cells have been shown to produce high levels of the sporulation-specific alkaline phosphatase. It has been shown by imrnunochemical means that seven of these mutants when starved of phosphate produce low levels of normal wild-type enzyme. The sporulation form of the enzyme from one mutant (P-l00) has been shown to be identical with the phosphatases from vegetative and sporulating cells of the wild type. It is proposed that all the mutants have regulatory defects in the control of the alkaline phosphatase from vegetative cells but nevertheless retain an intact structural gene for the enzyme and the control system for the phosphatase during sporulation.
Primary Structure of Apovitellenin I From Hen Egg Yolk and its Comparison With Emu Apovitellenin I
Authors: Dopheide TAA , Inglis AS
Published: July 2016

The amino acid sequence of apovitellenin I from hen egg yolk has been determined using both automatic and manual procedures; it comprises 82 residues. Hen apovitellenin shows considerable homology with emu apovitellenin I which contains 84 residues. Besides two deletions in the sequence, the hen protein differs in 28 positions from the emu protein; 26 of these positions may have arisen from single base changes. The changes are largely conservative ones, which suggest that the structure and function have been preserved despite extensive mutation.
Studies on the Zona Pellucida of Sheep Ova: Immune Lysis and Localization of Antibodies in Ova With, and Without, Zonae
Authors: Trounson AO , Pugh Anne , Moore NW
Published: July 2016

The susceptibility of fertilized sheep ova and oocytes, with and without zonae pellucidae, to lysis by complement plus antibodies in antisera raised against sheep ovaries, oocytes and sperm was examined in vitro. The presence of the zona reduced the proportion of ova lysed (8 % v. 57 %) and a large proportion of ova with zonae continued development in culture following exposure to antisera. Antisera to ovary and to oocytes lysed a higher proportion of ova than did antisera to sperm (51 and 56% v. 29%). There was no effect of age of fertilized ova (day 2, 4, 6; day 0 = day of oestrus) on susceptibility to lysis. Fluorescein-labelled antibodies from high-titre antisera to ovary and oocytes traversed the zona and attached to blastomeres. Following absorption of the antibody conjugates with sheep serum, fluorescein staining of ova with intact zonae was confined to the zona, whereas with zona-free ova the blastomeres were stained.
Biochemical Genetics of Resistance to Organophosphorus Acaricides in Three Strains of the Cattle Tick, Boophilus microplus
Authors: F Stone Bernard , Nolan James , A Schuntner Charles
Published: July 2016

Three aspects of the biochemical genetics of resistance to organophosphorus compounds in the Biarra (B), Mackay (M) and Ridgelands (R) strains of the cattle tick B. microp/us were studied. These were: decreased acetylcholinesterase (AChE) activity in adult brains of strains Band M; decreased AChE sensitivity to inhibitors in adult brains and in larvae of strains B, M and R; and increased detoxication in larvae and adult females of strain M. Comparisons were made with a susceptible reference strain (S). Microspectrophotometric estimations of AChE activity in histochemical preparations of whole brains showed that hybrids had levels of activity approximately intermediate between those of the parental strains. Homogenates of brains from hybrids assayed biochemically gave similar but more precise results which indicated that decreased brain AChE activity was neither recessive nor dominant (degree of dominance, D = + O� 02) in strain B and incompletely recessive (D = - O� 26) in strain M. The proportions of brains showing decreased AChE activity in testcross and F 2 progenies indicated that decreased AChE activity in strains Band M is controlled by single autosomal genes.
Fertility Test of Frozen Boar Semen
Authors: Osinowo O , Salamon S
Published: July 2016

The fertility results of two experiments are presented. In experiment 1, the semen was frozen in tris-fructose-EDTA or BF3 diluents at 0'25xl09/mI sperm concentration and extended after thawing with either seminal plasma (SP) or the freezing medium (FM) containing no cryoprotective agent. In the second experiment the semen was glycerolated by two methods, frozen at 1� 0 x 109/ml sperm concentration, and extended with FM before insemination. Fertility after double insemination within one oestrus with semen frozen in tris-fructose-EDTA or BF 3 diluents varied depending on the medium used for extension of thawed semen. The farrowing rates for semen frozen in the former diluent with FM and SP post-thawing media were 4/8 and 1/8 respectively, and for semen frozen in BF3 diluent with FM and SP post-thawing extenders 1/8 and 5/8 resp_ectively. The mean farrowing for the 32 animals inseminated was 34�4 %. Pregnancies for semen frozen in tris-fructose-EDTA and glycerolated at 30 or 5�e were 5/12 and 4/12 respectively, and for single and double inseminations 6/12 and 3/12 respectively. Of 24 animals inseminated 37� 5 % farrowed.