bluuebunny/crossref_metadata_2025 huggingface dataset:
MUTAGENICITY OF SOME COMMON PESTICIDES IN BARLEY
Authors: Grover I. S. , Tyagi P. S.
Published: November 2014

The perusual of literature reveals the desirability to screen the mutagenicity of pesticides. The present report deals with the cytological aberrations and chlorophyll mutations induced by Thiodan, Folithion, Lebaycid and Kitazin, employing barley as the test material. The chromosomal aberrations were examined both at mitotic and meiotic level. The root tip cells from pesticide treated barley grains revealed various abnormalities at metaphase including fragmentation, unequal chromosome, chromosomes with displaced satellite and increased number of chromosome. The laggards, bridges, tripolarity, tetrapolarity and micronuclei were seen at later stages. A positive correlation between dose and aberration was noticed. The meiotic analysis of PMC's from plants raised from pesticide treated barley grains, revealed quadrivalents and univalents at metaphase-I. Anaphase-I was atypical in having unequal distribution, laggards, bridges — single or double. The persistent bridges at telophase and micronuclei were not unfrequent. The pollen fertility was reduced. — M2 analysis at the seedling stage revealed albina, xantha and tigrina mutants. The tigrina's were more frequent. Lebaycid was the most effective while Thiodan was the most efficient.
THREE DIMENSIONAL RECONSTRUCTION OF QUADRIVALENTS AND MAPPING OF TRANSLOCATION BREAKPOINTS OF THE MOUSE TRANSLOCATIONS T(2;8) 26H AND T(9;17)138Ca
Authors: Choi Anthony H. C.
Published: November 2014

Three dimensional reconstruction from electron micrographs of serial sections reveals 18 synaptonemal complexes and a cross-shaped quadrivalent in the mouse pachytene oocytes of the heterozygous reciprocal translocations T(2;8)26H and T(9;17)138Ca. The unambiguous identification of translocation breakpoints on the quadrivalents has allowed the mapping of the translocation breakpoints on the chromosomes. The translocation breakpoints of T(2;8)26H are mapped at 73% and 45% from the telocentric centromeres of chromosomes 2 and 8, while those of T(9;17)138Ca are mapped at 41% and 45% from the telocentric centromeres of chromosomes 9 and 17 respectively. This report represents the first study of serial section reconstruction of a mammalian oocyte.
PGI-1, A SINGLE GENE IN TOMATO RESPONSIBLE FOR A VARIABLE NUMBER OF ISOZYMES
Authors: Tanksley Steven D.
Published: November 2014

In Lycopersicon esculentum Mill, the phosphoglucoisomerase (pgi) zymogram changes during seed germination. Dry seeds display bands A-D in similar intensities whereas seeds imbibed 24 h show almost exclusively the A and D bands. Evidence presented here supports the hypothesis that a single gene Pgi-1 codes for bands B-D, demonstrating that changes in isozymic banding patterns do not necessarily reflect a change in structural gene expression.
MULTIVARIATE ANALYSES OF POTATO HYBRIDS. II. DISCRIMINATION BETWEEN TUBEROSUM-ANDIGENA HYBRID FAMILIES AND THEIR RELATIONSHIP TO THEIR PARENTS
Authors: Tai G. C. C. , Tarn T. R.
Published: November 2014

In 1978 17 families from crosses between Tuberosum and long-day adapted Andigena parents were compared with each other and their parents using ten-hill plots. The mean performance of all Tuberosum-Andigena hybrid families was between the performances of the parental groups for six of eight traits, while in the best families the means of some yield traits exceeded the best parent. Multivariate analysis of seven traits gave five significant canonical variates which accounted for 96.6% of the variation. Two dimensional canonical diagrams showed a considerable overlap of the hybrid families and the Andigena parents, but very little overlap of either of these with the Tuberosum parents. Canonical distances between the hybrid families and the parents showed the families to be closer to the mid-parent value than to either parent, and closer to the Andigena parent than to the Tuberosum parent. The results suggest that the genetic effects of the Andigena parents are stronger than those of the Tuberosum parents, while non-additive effects are also important. Only the better Andigena parents and hybrid families are close to or overlap the distribution of the Tuberosum parents. Discrimination between hybrid families and their relationship to their parents provides information of value in determining future breeding strategies.
THE PROBABLE GENETICS OF DISTYLY IN GELSEMIUM SEMPERVIRENS (LOGANIACEAE)
Authors: Ornduff Robert
Published: November 2014

A crossing program with Gelsemium sempervirens (L.) Javme Saint-Hilaire was used to obtain progenies for determination of the genetic basis of distyly in this species. The results suggest that in G. sempervirens, pins are homozygous recessive (ss) and thrums are heterozygous (Ss) with thrum dominant over pin.
CYTOGENETIC ANALYSIS OF CHROMOSOMAL TRANSLOCATIONS IN THE TOMATO: PREFERENTIAL BREAKAGE IN HETEROCHROMATIN
Authors: Gill B. S. , Burnham C. R. , Stringam G. R. , Stout J. T. , Weinheimer W. H.
Published: November 2014

A tester set of eight translocations has been selected involving all 12 chromosomes of tomato (Lycopersicon esculentum Mill.). Using the entire tester set, seven other translocations were identified. Five others were identified, using information from crosses with certain of the testers and with additional translocations. Three lines are homozygous for two translocations (2 04 in the heterozygotes). There are several instances in which more than one stock involves the same two chromosomes. Cytological analyses of tomato translocations show that breakages that give rise to translocation chromosomes occur more frequently in centromeric and heterochromatic regions than in euchromatic and are not distributed according to pachytene chromosome length. A list of available tomato translocations with information on mode of production, source, and breakpoints is included.
GONOSOME-AUTOSOME TRANSLOCATIONS IN FOWL: MEIOTIC CONFIGURATIONS AND CHIASMA COUNTS FROM SINGLY AND DOUBLY HETEROZYGOUS COCKERELS
Authors: Blazak W. F. , Fechheimer N. S.
Published: November 2014

Many X-ray or chemical mutagen-induced chromosome translocations in domestic fowl (Gallus domesticus) are thought to involve microchromosomes as centromere donors to acentric macrochromosomal fragments. In order to study the involvement of microchromosomes in such translocations, and to investigate the possibility that such translocations are reciprocal, meiotic chromosomes from cockerels singly or doubly heterozygous for two different Z-autosome translocations were analyzed. Ring multivalents were observed in 74-94% of cells from cockerels bearing the different translocations, and the presence of microchromosomes in certain multivalents was apparent after C-banding. The results indicate that both Z-autosome translocations involve reciprocal exchange and that a microchromosome is indeed involved in one translocation. Chain multivalents at frequencies of 6% to 26% do not interfere with spermatogenesis in domestic fowl.
QUINACRINE FLUORESCENCE STUDIES IN PARIS POLYPHYLLA
Authors: Filion W. Gary , Vosa Canio G.
Published: November 2014

The chromosomes of Paris polyphylla Smith (2n = 10, 20) are the largest in the plant kingdom. They possess large regions of reduced fluorescence in addition to discrete fine banding. Excluding the 'bubbling', an effect of fixation, the discrete finer banding pattern is very constant and specific for each chromosome type. These finer bands, which may show either reduced or enhanced fluorescence, often do not traverse the chromosome; this could be attributed to the length of the banded segments involved (usually very short) and the degree of spiralization at mitotic metaphase which may not fill a complete gyre in the chromosome spiral. Cold-sensitive H-segments, which are located distally and show reduced fluorescence, are present only in the diploid plants. The interphase nuclei have a unique structure and appear composed of well defined minute granules which exhibit well differentiated regions of reduced and enhanced fluorescence when stained with Quinacrine.
X-CHROMOSOMAL NONDISJUNCTION INDUCED BY AGING OOCYTES OFDROSOPHILA MELANOGASTER: THE SPECIAL SUSCEPTIBILITY OF MATURE EGGS
Authors: Traut H.
Published: November 2014

In Drosophila melanogaster suppression of oviposition results in an aging of both mature and immature oocytes. When oviposition was suppressed for four days, the incidence of X-chromosomal nondisjunction (XXY exceptions) in mature oocytes was more than doubled, whereas in immature oocytes the nondisjunction frequency was not increased. It is shown that this special susceptibility of mature oocytes to aging-induced nondisjunction has to be considered in experiments on the induction of nondisjunction by chemical agents.
DIFFERENCES IN MOLECULAR WEIGHT BETWEEN CORRESPONDING ANIONIC PEROXIDASE ISOZYMES FROM TWO FLAX GENOTROPHS
Authors: Tyson H. , Fieldes M. A.
Published: November 2014

Anionic peroxidase isozymes from main stem tissues of adult plants of two flax (Linum usitatissimum L.) genotrophs were separated using acrylamide gel electrophoresis. A range of seven acrylamide concentrations was used for the gels, enabling the effect of gel concentration on relative mobility (Rm) to be examined. The regression of log (Rm) on gel concentration was linear for two of the four main isozymes found. Differences in linear regression slope between the L and S flax genotroph isozymes suggested genotroph differences in molecular weight.
GENETIC ANALYSIS OF A POPULATION OFTRIBOLIUM: VII. STABILITY: RESPONSE TO GENETIC AND DEMOGRAPHIC PERTURBATIONS
Authors: Desharnais R. A. , Costantino R. F.
Published: November 2014

A biological counterpart to mathematical stability analysis was demonstrated using the Tribolium model. The responses to deliberate demographic and genetic perturbations of T. castaneum populations, initially homozygous for the corn oil sensitive (cos) allele and near demographic equilibrium, were examined experimentally. An equilibrium was said to be ecologically stable if it was locally stable to perturbations in population numbers alone and genetically stable if it was locally stable to changes in allele frequencies alone. A qualitative stability analysis of the within population age-class interactions indentified several conditions for stability, such as, the product of the rate of egg cannibalism by larvae times the rate of pupal cannibalism by adults must be greater than the product of the "net" fecundity of adults times the overall larval viability. The populations which were subjected to the addition or removal of genetically similar adults or immature life stages were ecologically stable. The cultures altered by the introduction of the + allele were genetically unstable to this perturbation and converged to an average polymorphic cos equilibrium allele frequency of 0.42. The incorporation of the + allele into populations initially homozygous for the cos allele was examined in terms of natural selection in a density-regulated population. The experimental data supported the theoretical prediction that selection is expected to move an ecologically stable system toward an evolutionarily stable strategy resulting in the maximization of adult numbers.
DIALLEL ANALYSIS OF FLOWERING-TIME IN CORN (ZEA MAYS) USING A CORN HEAT UNIT TRANSFORMATION
Authors: Rood S. B. , Major D. J.
Published: November 2014

A set of eight corn (Zea mays L.) inbreds was studied in a diallel cross over two years and in a growth room to investigate general and specific combining ability for flowering-time. Diallel analysis of days from emergence to flowering revealed a failure of the joint Wr/Vr regression in one of the years, indicating a lack of agreement with the simple additive-dominance model of inheritance. The array position changed across the years and environments, complicating genetic interpretation. Transforming data of flowering-time to cumulative corn heat units (CHU) to flowering gave a better fit. Joint regression was satisfactory and array position was more consistent across years and environments. Dominance was incomplete for low CHU to flowering. Positive (increasing CHU) and negative, as well as dominant and recessive, alleles were in about equal frequencies. Heritability estimates in the broad- and narrow-sense were high. The estimates of general combining ability were higher than the estimates of specific combining ability in all studies.
HOMOZYGOUS PERICENTRIC INVERSIONS AND OTHER STUDIES OF INVERSIONS ON CHROMOSOME 3 IN THE MOSQUITO ANOPHELES ALBIMANUS
Authors: Suguna S. G. , Seawright J. A. , Joslyn D. J. , Rabbani M. G.
Published: November 2014

Two radiation-induced pericentric inversions on chromosome 3 in Anopheles albimanus Wiedemann have been established in homozygous stocks. In(3)17 and In(3)22 cover about 82% and 42%, respectively, of chromosome 3 and should be very useful as crossover suppressors in genetic crosses. In addition, three double-heterozygote stocks were established by combining inversions that had similar breakpoints but were viable only as heterozygotes. These balanced-lethal double heterozygotes can serve as a source of inversion gametes for use in experimental crosses and can be used in surveying populations for lethal chromosomes. Assays of the partial sterility inherent in males heterozygous for a pericentric inversion and a male-linked translocation indicated that the combination of inversions and translocations could be used in genetic control schemes.
PURE AND MOSAIC CLONES — A REFLECTION OF DIFFERENCES IN MECHANISMS OF MUTAGENESIS BY DIFFERENT AGENTS IN SACCHAROMYCES CEREVISIAE
Authors: Nasim A. , Hannan M. A. , Nestmann Earle R.
Published: November 2014

The induction of pure and mosaic clones has been studied in haploid G1 cells of Saccharomyces cerevisiae. Following treatments with ultraviolet light, methyl methanesulfonate, ethyl methanesulfonate, nitrous acid, and N-methyl-N′-nitro-N-nitrosoguanidine, the relative proportions of pure mutant clones varied from 25 to 100% at comparable survival levels. Ultraviolet light and methyl methanesulfonate produced mainly pure mutant clones, whereas ethyl methanesulfonate and nitrous acid produced mainly mosaics at 59 to 100% survival levels. The ratio of pure to mosaic clones induced by nitrosoguanidine fell between these two classes. These results are consistent with a classification of mutagens on the basis of repair and replication-dependent mechanisms of mutagenesis in other organisms. Agents having actions similar to ultraviolet light may produce mainly pure clones through a pre-replicative process involving an error-prone DNA repair process. Others may produce mainly mosaic mutants due to the different nature of DNA lesions which may require a replication-dependent process for fixation of mutations. Preliminary data from combined treatments of mutagens belonging to two different classes (i.e. ultraviolet light and nitrous acid) suggest the possibility of an interaction between these agents, resulting in a higher proportion of pure clones, possibly due to an inducible process. Studies of induced frequencies of pure and mosaic clones may be useful in the characterization of mutagens with functional differences.
COMPARISON OF THE CROSSABILITY OF RYE (SECALE CEREALE) AND HORDEUM BULBOSUM ONTO WHEAT (TRITICUM AESTIVUM)
Authors: Falk D. E. , Kasha K. J.
Published: November 2014

Fifty-six wheat (Triticum aestivum L.) lines representing a wide diversity of germplasm were screened for crossability with rye. Seed set values ranged from 0.0% to 95.4% of the florets pollinated. Twenty-eight of these wheat lines representing the range of crossability with rye were then pollinated with tetraploid Hardeum bulbosum L. Seed set ranged from 0.0% to 32.2%. Those wheats giving seed set with H. bulbosum generally had medium to high crossability with rye. A high correlation (r = 0.75) was obtained for crossability of rye and H. bulbosum on wheat, indicating that the main genetic system (Kr1 and Kr2) governing crossability with rye is also the main system operating in crosses with H. bulbosum. Evidence for additional factors influencing crossability and for differences between rye and H. bulbosum is provided. Hybrids between wheats having different crossability levels exhibited intermediate crossability levels with rye but very low crossability with H. bulbosum. Hordeum bulbosum genotypes differ in their ability to effect seed set.
RADIATION INDUCED SEX CHROMOSOME LOSS AS AN INDICATOR OF THE OPTIMAL STAGE DURING SPERMATOGENESIS FOR THE INDUCTION OF COMPOUND CHROMOSOMES INLUCILIA CUPRINA
Authors: Maddern R. H.
Published: November 2014

Radiation induced sex chromosome loss has been used to determine the optimal stage at which to irradiate developing male gonial cells in order to produce compound autosomes. In Lucilia it was found that the optimal stage for inducing sex chromosome loss was correlated with the stage at which the greatest number of radiation induced compound chromosomes was recovered. By analogy with Drosophila the data suggest that the 2 to 3 day old pupa is the earliest stage at which spermatocytes are produced in Lucilia. Using this method it should be possible to determine the optimal age at which to irradiate in order to produce compound chromosomes in other pest species where information relating spermatogenic development to age is limited.
INHERITANCE OF SEED YIELD AND ITS COMPONENTS IN SAFFLOWER
Authors: Kotecha Ashok
Published: November 2014

The parents, F1 and F2, from four crosses of safflower (Carthamus tinctorius L. and C. palaestinus Eig.) were studied to estimate heritability, gene action and mode of inheritance of head number, seed weight and seed yield. Low variances of nonsegregating populations suggested that environmental effects on seed weight were not strong and that variability was largely genetic; however, environmental effects were strong on head number and seed yield. Maternal effects were nonsignificant for all traits studied. The broad sense heritability estimates ranged from 4.4 to 16.7%, 21.7 to 81.8% and 66 to 85.5% for head number, seed yield and seed weight, respectively. In all F2's, a continuous distribution was observed, suggesting multiple factor inheritance for head number, seed weight and seed yield. Mathers and Jinks' three parameter model indicated that epistasis was not important for head number and seed yield; however, epistasis was important for seed weight. Flower color and anthocyanin pigmentation of cotyledonary midvein were inherited independently. Anthocyanin pigmentation was associated with head number, seed yield and seed weight; however, striped hull and flower color were not associated with head number, seed yield or seed weight. There was a significant positive correlation between seed yield and head number.
GENETICAL AND MORPHOLOGICAL VARIATION IN THE EELPOUTZOARCES VIVIPARUS
Authors: Christiansen Freddy Bugge , Nielsen Birte Vivi , Simonsen Vibeke
Published: November 2014

The geographical variation in genotypic and morphological composition is compared for populations of the eelpout, Zoarces viviparus (L.), in Mariager Fjord, Denmark. The morphological characters are number of vertebrae, dorsal fin hard rays, pectoral fin rays, and pigment spots of dorsal fin. The geographical variation in these traits agrees well with that described by Johs. Schmidt half a century ago. The electrophoretical variation at five enzyme loci: Ada, EstIII, Got, PgmI and PgmII is described. The scale of differentiation is comparable for the two classes of traits, and differentiations between local populations down to a distance of about 10 km are shown.
DEVELOPMENTAL CYTOLOGY OF 13 GENETIC MALE STERILE LOCI IN MAIZE
Authors: Albertsen M. C. , Phillips R. L.
Published: November 2014

Thirteen nonallelic genetic-male sterile loci of maize (Zea mays L.) were investigated cytologically to determine the microsporogenesis breakdown characteristics for each mutant. These male-sterile mutants included ms1, ms2, ms5, ms6, ms7, ms8, ms9, ms10, ms11, ms12, ms13, ms14, and ms17 in A632 and 0h43 inbred backgrounds. Male-sterile mutants ms8 and ms9 resulted in abnormal microspore (pollen) mother cells that exhibited nearly normal nuclear development but abnormal cellular development. These mutants had the earliest effect on microsporogenesis. Male-sterile mutants ms5, ms11, and ms14 had the latest effect on microsporogenesis in that microspores developed until the microspore mitosis stage. Other male-sterile mutants seemed to have similar expressions when compared with each other. Mutants ms2 and ms7 both lacked significant microspore wall formation at the time of microspore collapse. Mutants ms10 and ms13 were similar in that the microspore wall developed to approximately one-half the normal thickness before microspore collapse. A unique feature of ms1 was the occurrence of an abnormally thickened microspore wall. Almost complete microspore wall development occurred in ms12 plants despite nuclear degradation. Mutant ms6 was cytologically and genetically similar to polymitotic (po). Mutant ms17 had variable expression that most notably affected spindle formation. These observations may be useful in utilizing genetic male sterility in maize hybrid seed production schemes.
THE ANALYSIS OF MEIOSIS IN HYBRIDS. I. ANEUPLOID HYBRIDS
Authors: Kimber G. , Alonso L. C. , Sallee P. J.
Published: November 2014

The use of telocentric chromosomes in the analysis of the genomic relationships of wheat Triticum aestivum L. em Thell. and its relatives is described and 20 examples are given. The connection between this method of analysis and other mathematical theories of chromosome pairing in hybrids is established. A demonstration of the validity of the assumption that all chromosome arms pair at an equal frequency in calculating expected meiotic analyses is presented. This establishes a practical basis for the development of further mathematical models for predicting meiotic chromosome behavior. Numerical values of the genomic relationships of wheat and its immediate relatives are given.
CHROMOSOME DAMAGE INDUCED BY ARTIFICIAL SEED AGING IN BARLEY. I. GERMINABILITY AND FREQUENCY OF ABERRANT ANAPHASES AT FIRST MITOSIS
Authors: Murata Minoru , Roos Eric E. , Tsuchiya Takumi
Published: November 2014

In order to study the genetic changes which occur during seed storage, barley (Hordeum vulgare L. 'Himalaya') seeds were subjected to artificial aging using six combinations of temperature (21 °C, 32 °C, and 38 °C) and seed moisture content (12% and 18%). With increasing time in storage, germination of the seeds was delayed and reduced. Abnormal seedlings without roots also occurred with increased storage. Higher temperature and seed moisture content induced rapid loss of germinability. At the first mitotic division in the root tips, the frequency of aberrant anaphases and of roots with aberrations increased with increased storage time. The frequencies of aberrant anaphases and of roots with aberrations were also increased by higher temperature and seed moisture content. Frequencies of aberrant anaphases and of roots with aberrations were negatively correlated with germination percentage. This indicated that the frequency of chromosomal aberrations induced by seed aging might be estimated from the germination percentages.
THE CHROMOSOME CONSTITUTION OF HEXAPLOID WINTER TRITICALES
Authors: Lukaszewski Adam J. , Apolinarska Barbara
Published: November 2014

Eighty-three advanced winter triticales (× Triticosecale Wittmack) derived from various initial crosses and seven unselected triticale × bread wheat (Triticum aestivum L.) F5 lines were screened for the presence of rye chromosomes. Seventy-six advanced lines had seven pairs of rye (Secale cereale L.) chromosomes, suggesting selection pressure favoring retention of the complete rye genome. The results for unselected lines suggest the operation of natural disruptive selection for parental types. Possible factors involved in yielding different chromosome constitutions in winter and spring triticales are discussed.
BIOLOGICAL EFFECTS OBSERVED IN MAMMALS MAINTAINED IN AN AREA OF VERY HIGH NATURAL RADIOACTIVITY
Authors: Léonard A. , Delpoux M. , Chameaud J. , Decat G. , Léonard E. D.
Published: November 2014

Male rabbits (Oryctolagus cuniculus) were maintained for a 28-month period on the floor of a hut built at a site in southwestern France where the dose rate from natural radioactivity amounts to about 8 mrad/h. Male and female BALB/c mice (Mus musculus) were also placed in the hut during the summer period. The observations performed on those animals demonstrate that exposure to high natural radiation can increase the frequency of chromosome aberrations in somatic cells and indicate also that fertility in males and females is affected in an inverse manner. Model experiments with radon exposure of laboratory rabbits under controlled conditions have shown that the chromosome aberrations observed in somatic cells are not due to the radon exposure but essentially to gamma irradiation.
GENETICS OF THE BLUE MUSSEL MYTILUS EDULIS (L): NONADDITIVE GENETIC VARIATION IN LARVAL GROWTH RATE
Authors: Newkirk G. F. , Haley L. E. , Dingle J.
Published: November 2014

Through a series of factorial matings, it has been determined that in one population of the mussel, Mytilus edulis (L), there is some additive genetic variance for larval growth rate, but the predominant genetic component is nonadditive. In two separate experiments the sire-dam interaction which estimates 25% of the dominance variance plus other non-additive components accounted for 9% to 15% of the total variance in larval growth rate.
STUDIES ON COMBINING ABILITY IN STRAWBERRY (FRAGARIA × ANANASSA): I. NUMBER OF INFLORESCENCES, NUMBER OF FLOWERS, DAYS TO MATURITY AND NUMBER OF FRUITS
Authors: Lal Shri Dhar , Seth Jitendra Nath
Published: November 2014

A 10 × 10 complete diallel cross was carried out in the strawberry (Fragaria × ananassa Duch.). Significant general (gca) and specific combining ability (sea) effects were recorded. The variances due to general combining ability exceeded the variances due to specific combining ability. Cytoplasmic effects were also noted. The variety Kalimpong Local was found to be a good general combiner for number of inflorescences, number of flowers and number of fruits. The variety Albritton had highest gca effect for number of inflorescences. The variety Premier was a good general combiner for number of flowers. The Redcoat showed highest gca effect for days to maturity. The best specific combination for number of inflorescences was Phenomenal × Jeolikote Local in F1 and Premier × Kalimpong Local in F2. For number of fruits Albritton × Kalimpong Local and Premier × Cavalier were the best.
GENETICS OF GLOSSINA MORSITANS MORSITANS (DIPTERA: GLOSSINIDAE). V. DEFINITION AND PRELIMINARY MAPPING OF LINKAGE GROUPS I AND II
Authors: Gooding R. H.
Published: November 2014

Linkage group I is defined as the loci on the differential part of the X-chromosome of adult Glossina morsitans morsitans Westwood. Three loci are known and their order on the X-chromosome has been demonstrated as ocra (body color), salmon (eye color), and Apk (arginine phosphokinase, E.C. 2.7.3.3) with 38 map units separating the first two loci and 32 to 41 separating the second two. This region of the X-chromosome does not contain the chromosomal inversion known to occur in the Handeni line of G. m. morsitans. Linkage group II is defined as the autosome carrying the locus Xo (xanthine oxidase, E.C. 1.2.3.2), and it is demonstrated to carry also the loci Ao (aldehyde oxidase, E.C. 1.2.3.1) and Odh (octanol dehydrogenase, E.C. 1.1.1.73). Ao and Odh are within 0.36 map units of each other and have not been separated by recombination; this pair of loci occur about 48 map units from Xo. During mapping experiments, no evidence for genetical recombination was found in male G. m. morsitans.
MEIOTIC AND MITOTIC CHROMOSOMES OF THE COTTON BOLL WEEVIL (COLEOPTERA: CURCULIONIDAE)
Authors: North David T. , Leopold Roger A. , Childress Dinah
Published: November 2014

Karyotypic analyses of mitotic and meiotic chromosomes of the cotton boll weevil, Anthonomus grandis grandis Boheman, revealed the diploid number to be 42 (20 autosomes plus an Xy). The Xy has the typical parachute shape configuration as described for other related species. The evidence for supernumerary chromosomes is also presented.
BANDING STUDIES IN THE VOLCANO RABBIT, ROMEROLAGUS DIAZI AND CRAWSHAY'S HARE LEPUS CRAWSHAYI. EVIDENCE OF THE LEPORID ANCESTRAL KARYOTYPE
Authors: Robinson T. J. , Elder Frederick F. B. , Lopez-Forment W.
Published: November 2014

G- and C-banded karyotypes are presented for the North American volcano rabbit, Romerolagus diazi (Ferrari-Perez, 1893) and an African hare species, Lepus crawshayi (de Winton, 1899). Both species are characterized by 2n = 48. While noticeable differences in the amounts of constitutive heterochromatin between the two taxa are apparent, the remarkable similarity of both chromosome morphology and G-banding pattern indicates a common evolutionary origin of the two genera. These observations support the hypothesis that the leporid ancestral karyotype has been maintained in the hares and certain of the rabbit taxa.
AGRONOMIC AND QUALITY CHARACTERISTICS OF WHEAT LINES WITH LEAF RUST RESISTANCE DERIVED FROM TRITICUM SPELTOIDES
Authors: Knott D. R. , Dvořák J.
Published: November 2014

Eleven lines of wheat (Triticum aestivum L.) carrying resistance to leaf rust (Puccinia recondita Rob. ex. Desm.) derived from five accessions of Triticum speltoides Tausch were grown in yield tests in 1977 and 1979. The grain was tested for quality characteristics in both years. Although the lines had been backcrossed four or five times to either Manitou or Neepawa, only four of the eleven showed any real promise of equalling their recurrent parent in agronomic and quality characteristics. Lines derived from the same accession of T. speltoides were surprisingly variable. The generally deleterious effects of the transferred chromatin are due either to genes linked to the genes for leaf rust resistance plus incomplete compensation by the speltoides chromosome segment for the aestivum segment it replaced, or to the effects of additional translocations that were not eliminated during backcrossing. A second cycle of homoeologous recombination is proposed as a way to eliminate some of the deleterious genes.
THE EFFECTS OF GAMMA IRRADIATION OF HUMAN FIBROBLASTS ON HUMAN/CHINESE HAMSTER SOMATIC CELL HYBRIDS
Authors: Donald L. J. , Wang H. S. , Holliday N. J. , Hamerton J. L.
Published: November 2014

Human fibroblast cells were exposed to 0, 10, 20, or 40 Grays of gamma rays and then fused with unirradiated Chinese hamster cells deficient in HPRT. THAG selection system was used to ensure that only hybrid cell lines could survive. The time of appearance of pickable hybrid colonies and the frequency of dishes without any colonies were related to radiation dose. As the radiation dose increased, there was a positive correlation with frequency of cells with abnormal nuclei and a negative correlation with frequency of human chromosomes. Additionally, the hamster chromosomes had damage similar to that produced by radiation; the frequency of damaged hamster chromosomes was positively correlated with radiation dose.
ETUDE DE L'HEREDITE DE PHOSPHATASES ACIDES CHEZ LE DACTYLE (DACTYLIS GLOMERATA) DIPLOIDE ET TETRAPLOIDE
Authors: Lumaret R.
Published: November 2014

Starch gel electrophoresis of leaves of diploid and more particularly tetraploid orchard grass (Dactylis glomerata L.) from cultivars as well as natural populations disclosed several anodal stable bands with fast migration and phosphatasic activity. Six different phenotypes with one band, many others with three regular bands or six bands (only in the tetraploid individuals), were observed, showing the dimeric structure of the enzymes. Inheritance studies showed one polymorphic locus with six codominant alleles AcPH 11.00, AcPH 10.95, AcPH 10.90, AcPH 10.88, AcPH 11.02and AcPH 11.04with differences in enzymatic expression. AcPH1.00and AcPH 10.90have been found in the two ploidy levels. Results from the tetraploid progenies involved tetravalents in meiosis for individuals originating from cultivars but bivalents in the wild plants. The two loci AcPH 1 and GOT 1 (this last one coding for a glutamate oxaloacetate transaminase) are not linked and seem to be located on different chromosomes.
SELECTION FOR SERUM CHOLESTEROL, VOLUNTARY PHYSICAL ACTIVITY, 56-DAY BODY WEIGHT AND FEED INTAKE IN RANDOMBRED MICE. I. DIRECT RESPONSES
Authors: Dunnington E. A. , White J. M. , Vinson W. E.
Published: November 2014

A five-generation selection experiment was conducted with randomly bred ICR mice. Lines were developed for high (CH) and low (CL) serum cholesterol (SC), voluntary physical activity (lines AH and AL), 56-day body weight (lines WH and WL), and feed intake (lines IH and IL). An unselected randomly bred control line was maintained with each pair of selection lines (CC, AC, WC and IC, respectively). Selection was based on individual performance in SC, activity and weight lines, and on within-sex, among full-sib family selection in intake lines. Genetic responses (selected line generation means deviated from control line generation means and regressed on generation number) were different from zero (P<0.05) in CH males and females, CL males, AH males and females, AL males, WH males and females, WL males and females, and IH females. Realized heritabilities which did not differ (P<0.05) between sexes were: 0.43±0.05 (line CH), 0.37±0.06 (line CL), 0.26±0.08 (line AH), 0.16±0.04 (line AL), 0.33±0.05 (line WH), 0.40±0.05 (line WL), 0.42±0.06 (line IH). In Line IL heritabilities of males and females differed (P<0.05) from each other (0.08±0.06 and 0.29±0.06, respectively).
VEGETATIVE AND FLORAL CHARACTERS OF PETUNIA SPECIES HYBRIDS AS RELATED TO THE ORIGIN OF PETUNIA HYBRIDA
Authors: Sink K. C.
Published: November 2014

Three vegetative and six floral characters of Petunia axillaris (Lam.) B.S.P., P. inflata Fries, P. parodii W.C.S., and P. violacea Lindl., their reciprocal hybrids and 14 P. hybrida Vilm. cultivars were measured and comparisons made to gain further information on the origin of the garden petunia. Evaluation of the floristic data plus flower color requirements and breeding behavior excluded P. parodii as a possible ancestor. P. axillaris crossed with P. inflata produced hybrids that may account for the range of variability observed in the cultivars, flower color array and introduction of self-incompatability genes.
GENETIC ANALYSIS OF QUANTITATIVE CHARACTERS IN CIGAR AND PIPE TOBACCO NICOTIANA TABACUM II. GRADES OF CIGAR FILLER TOBACCO
Authors: Ogilvie I. S. , Kozumplik V.
Published: November 2014

A diallel cross of four cigar and one pipe tobacco (Nicotiana tabacum L.) was analyzed for the following characters in samples of cured tobacco: (1) percentage of light filler; (2) percentage of heavy filler; (3) percentage of top filler; (4) percentage of bottom filler; (5) percentage of total filler; (6) percentage of marketable trash and (7) total percentage of marketable tobacco. The experiment was performed over three years with four replications. Analysis was done for general combining ability and specific combining ability. General combining ability was greater than specific combining ability for all parameters, although specific combining ability effects were also present for all parameters with the exception of total marketable tobacco. Reciprocal effects were completely absent. The line Pennbel 69 showed a negative general combining ability effect for all grades of filler, total filler and total marketable tobacco with a positive effect for percentage of marketable trash. High positive specific combining ability effects for percentage total filler and high negative specific combining ability effects for percentage marketable trash were shown by crosses of Pennbel 69 with the other four cultivars.
KARYOLOGICAL STUDIES OF A FEMALE VARIABLE OYSTERCATCHER (HAEMATOPUS UNICOLOR)
Authors: Baker Allan J. , Parslow M. , Chambers D.
Published: November 2014

The chromosomes of Haematopus unicolor Forster were examined from cultures of embryo cells. The diploid complement for one individual was estimated to be 2n = 72, comprising 35 autosomes and a pair of sex chromosomes. The W chromosome is a medium size submetacentric. It is smaller than the Z and is the only chromosome with noncentromeric constitutive heterochromatin. The only other species of this genus whose karyotype is known, H. ostralegus, differs from H. unicolor in having a smaller diploid complement (2n = 66) and a telocentric W chromosome. Comparative karyological studies of other species will likely provide valuable data for clarifying the systematics of the Haematopodidae.
CHROMOSOME NUMBERS IN SOME TRIFOLIUM SPECIES WITH A KARYOTYPE FOR T. PHYSODES
Authors: Giri N. , Taylor N. L. , Collins G. B.
Published: November 2014

Chromosome numbers for eight Trifolium species were determined. These represented first counts for T. philisticum Zoh. and T. strepens Crantz. and confirmation for T. amabile H.B.K., T. badium Schreb., T. megalanthum Steud., T. virginicum Small., T. aureum Poll., and T. physodes Stev. ex M.B. Six of the eight species had 2n = 16 chromosomes. Trifolium megalanthum, T. badium, T. aureum and T. strepens were found to have 2n = 32, 2n = 14, 2n = 16, and 2n = 16 chromosomes, respectively. T. strepens and T. aureum have the same chromosome number and morphology, and we accept them as the same species under the name of T. aureum. Karyotypic analysis of T. physodes revealed two basic types of chromosomes with nearly median and nearly submedian centromeres. Chromosome mean percentage lengths for T. physodes varied from 16.24 to 10.18 and the arm ratios varied from 1.14 to 1.68.
SOME CHARACTERISTICS OF HEXAPLOID TRITICALE SUBSTITUTION LINES INVOLVING THE A-, B-, AND D-GENOME CHROMOSOMES OF WHEAT
Authors: Larter E. N. , Noda K.
Published: November 2014

Three hexaploid (2n = 6x = 42) triticale lines (× Triticosecale Wittmack) were synthesized in which a specific chromosome of either the A or B genomes was replaced by a homoelogous chromosome of the D genome of wheat (Triticum aestivum L. em Thell.). Two of the substitutions involved the B genome [substitution lines 1D(1B)R-4 and 6D (6B)R-5] and the third involved the A genome [4D(4A)R-1]. Polyacrylamide gel electrophoresis of gliadin proteins produced distinct differences in banding patterns between the three substitutions and provided a definitive method for the identification of specific chromosome substitutions in triticale. Plant and spike characteristics of the substitution triticales were similar to those of the control (unsubstituted) triticale. Substitution 6D(6B)R-5 exhibited extremely low fertility and was difficult to maintain. The substitution 4D(4A), on the other hand, appeared to have no effect on fertility, while substitution 1D(1B) reduced fertility by almost one-half of that of the control triticale. Chromosome pairing in substitution 4D(4A)R-1 was regular whereas 1D(1B)R-4 exhibited an average of five univalents/cell at MI. Limited seed supply prevented a meiotic study of 6D(6B)R-5. Flour proteins of the three substitution triticales ranged from 15.8% for 4D(4A)R-1 to 18.0% for 6D(6B)R-5. A comparison of the three substitutions for amino acid composition indicated that line 6D(6B)R-5 was 25% higher in methionine than the control, while in substitution 4D(4A)R-1 methionine content was reduced by 53%.
CYTOGENETIC ANALYSIS OF PLANTS REGENERATED FROM OAT (AVENA SATIVA) TISSUE CULTURES; HIGH FREQUENCY OF PARTIAL CHROMOSOME LOSS
Authors: McCoy T. J. , Phillips R. L. , Rines H. W.
Published: November 2014

The frequency and types of chromosomal variability in regenerated Avena sativa L. plants were assessed by detailed meiotic analysis on 655 regenerated plants. Tissue cultures were initiated from immature embryos of the varieties Lodi and Tippecanoe and maintained by monthly subculturing. Plants were regenerated from 4-, 8-, 12-, 16- and 20- month-old cultures. Regenerated plants with cytogenetic alterations were common, although Lodi cultures produced a higher frequency of cytogenetically abnormal plants at each regeneration cycle than Tippecanoe cultures. After four months in culture, 49% of Lodi regenerated plants were cytogenetically abnormal, whereas only 12% of Tippecanoe regenerated plants were abnormal. The frequency of cytogenetically abnormal, regenerated plants increased with culture age. After 20 months in culture 88% of Lodi regenerated plants and 48% of Tippecanoe regenerated plants were cytogenetically abnormal. The most common cytogenetic alteration was chromosome breakage, followed by loss of a chromosome segment resulting in a heteromorphic pair at diakinesis. Of the regenerated plants classified as cytogenetically abnormal, 41% of Lodi plants and 66% of Tippecanoe plants had lost a portion of one or more chromosomes. Other alterations included trisomy, monosomy and interchanges. Chromosome instability associated with oat tissue cultures has several possible uses.
GENETICS OF GLOSSINA MORSITANS MORSITANS (DIPTERA: GLOSSINIDAE). VI. MULTILOCUS COMPARISON OF THREE LABORATORY POPULATIONS
Authors: Gooding R. H. , Rolseth B. M.
Published: November 2014

Three strains (Kariba, Handeni, and ocra) of Glossina morsitans morsitans Westwood were examined by polyacrylamide gel electrophoresis to determine the extent of genetic similarity among the strains. Males were examined for 11 thoracic enzymes, one testicular enzyme, and one midgut enzyme. Tetrazolium oxidase, manganese stimulated malate dehydrogenase, an alpha-glycerophosophate deyhdrogenase, and testicular esterase were monomorphic. Variation was found in xanthine oxidase, aldehyde oxidase, octanol dehydrogenase, an alpha-glycerophosophate dehydrogenase, malate dehydrogenase, midgut alkaline phosphatase, two esterases, arginine phosphokinase, and glucose 6-phosphate dehydrogenase. Loci for the latter two enzymes are on the X-chromosome; all others are on autosomes. Allele frequencies in the three strains indicated that the Kariba and ocra strains are more closely related to each other than either is to the Handeni strain. These genetic similarities are consistant with the geographic origins of the strains. The mean heterozygosity per locus was highest (16.7% and 16.0%) in the two strains (Kariba and ocra) which have the highest reproductive capacity under laboratory conditions, and lowest (7.3%) in the strain (Handeni) which has the lowest reproductive capacity.
SELECTION FOR FEED EFFICIENCY IN MICE UNDERAD LIBITUMAND RESTRICTED FEEDING TERMINATED BY FIXED TIME OR QUANTITY OF INTAKE
Authors: Parker R. J. , Bhatti M. A.
Published: November 2014

Mass selection for feed conversion efficiency (FCE) in mice was practiced for six generations in two lines fed ad libitum (AL) and two lines restricted to 80% of ad libitum (R). In one line of each pair of selected lines the test period was terminated after a fixed time (14 days) (TAL and TR) and in the second line of the pair after consumption of a fixed quantity of feed (WAL and WR). A random mating control line (C), also fed ad libitum was maintained throughout the study. Correlated traits measured were initial weight, final weight, weight gain, feed consumption and litter size. A significant response in FCE was found in the TR and WR lines, the regression of response on generation number being −1.36 ± 0.31 and −1.09 ± 0.39 respectively. There was a significant decrease in initial weight on test in the TR and WAL lines and in those lines mature body weight was significantly lower than in the C line when measured in the sixth generation. Heritability of FCE was higher in the restricted lines (0.31 ± 0.12 for TR and 0.37 ± 0.29 for WR) than in the ad libitum lines (0.13 ± 0.20 for TAL and 0.13 ± 0.25 for WAL). Heritability of FCE was 0.17 ± 0.31 in the C line. Phenotypic and genetic correlations between FCE and weight gain were high and negative in all lines. Progeny from each line were tested in each of the other feeding regimes each generation to measure line × feeding regime interaction. This interaction was statistically significant.
RADIATION INDUCED RECIPROCAL TRANSLOCATIONS AND INVERSIONS INANOPHELES ALBIMANUS
Authors: Kaiser P. E. , Seawright J. A. , Benedict M. Q. , Narang S. , Suguna S. G.
Published: November 2014

Reciprocal translocations and inversions were induced in Anopheles albimanus Wiedemann by irradiation of males with X rays. A total of 1669 sperm were assayed, and 175 new aberrations were identified as follows: 102 reciprocal translocations (67 autosomal and 35 sex-linked), 45 pericentric inversions, and 28 paracentric inversions. Eleven of the translocations were nearly whole-arm interchanges, and these were selected for the construction of "capture systems" for compound chromosomes. Two double-heterozygous translocation strains and four homozygous translocation strains were established. Anopheles albimanus females were irradiated, and a pseudolinkage scheme involving mutant markers was employed to identify reciprocal translocations. The irradiation of females was very inefficient: only one translocation was recovered from 1080 ova tested.
ELECTRON MICROSCOPY OF SILVER-STAINED CORE-LIKE STRUCTURES IN METAPHASE CHROMOSOMES
Authors: Burkholder Gary D. , Kaiserman Morton Z.
Published: November 2014

Chinese hamster metaphase chromosomes, stained with ammoniacal silver and examined by electron microscopy, were covered with fine silver grains of variable size. In addition, many chromosomes contained linear aggregates of silver grains running continuously from one end of each chromatid to the other, forming a core-like structure. Extensive deposits of silver were observed over the nucleolar organizers and the centromeric regions, and the silver precipitate in the latter region appeared to be a localized differentiation of the core-like structure. The silver cores ranged from thin to thick and continuous to discontinuous elements in different chromosomes. This extreme variability suggests that these cores are not true structural components of chromosomes. The amount of silver deposit over any given chromosome region may simply reflect the concentration of chromatin in that region of the chromosome. The silver-stained core-like structure probably reflects an underlying difference in the concentration of chromatin in the central and peripheral region of each chromatid. Such differences in chromatin concentration may be induced during the prolonged hypotonic treatment required for the subsequent visualization of cores.
GAMETOCIDAL CHROMOSOMES OF THREE AEGILOPS SPECIES IN COMMON WHEAT
Authors: Endo T. Ryu
Published: November 2014

Single chromosomes from Aegilops triuncialis L. (2n = 28, CCCuCu), Ae. sharonensis Eig (2n = 14, S1S1), and Ae. longissima S. &M. (2n = 14, S1S1) were added respectively to common wheat Triticum aestivum L. cv. 'Selkirk' (2n = 42, AABBDD) in monosomic condition and confirmed to have a gametocidal action on common wheat gametes lacking the Agilops chromosome. Three double monosomic addition lines, which had two of the three Aegilops chromosomes, were produced from the monosomic addition lines, and relationships among the three Aegilops chromosomes were studied. The Aegilops chromosomes did not pair with one another in the double monosomic addition lines. In the progeny of the double monosomic addition lines with the triuncialis and sharonensis chromosomes or with the triuncialis and longissima chromosomes, both Aegilops chromosomes were almost always transmitted through male and female gametes. In the progeny of the double monosomic addition line with the sharonensis and longissima chromosomes, only the longissima chromosome was preferentially transmitted through male and female gametes. Thus, the three Aegilops chromosomes were proved to be different from one another in the gametocidal action in common wheat.