This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.

Studies of somatic cell genetics in larches (Larix spp.) were carried out using somatic hybridization, cytogenetics as well as fluorescence in situ hybridization. Haploid embryogenic protoplasts are ideal sources for somatic hybridization if they possess stable chromosome complements. In my protoplast fusion experiments, I used diploid embryogenic protoplasts because genetic variation was detected in the haploid lines available. Cytogenetics coupled with fluorescence in situ hybridization was used to reveal genetic instabilities in haploid embryogenic lines as well as to produce a standard karyotype of Larix decidua. A diploid embryogenic culture of tamarack (Larix laricina, line L2) was used as one of the fusion partners while the other partner used was one of the two hybrid larches (Larix x leptoeuropaea, line L5 and Larix x eurolepis, line L6 ). The selection system was based on complementation of metabolic inhibition (with sodium iodoacetate) of tamarack and the lack of ability to produce mature embryos of the hybrid larches. Ideally, only the heterofused cells would have been able to regenerate. The vital fluorescent dyes, DiOC₆ and R6 , were used to stain protoplasts of each parent to determine fusion events and frequencies. I compared fusion firequency as well as cell division between fusion mediated by PEG or electric pulses. PEG-mediated fusion resulted in 14-18 % of heterofused cells. All electrofusion treatments gave much lower fusion frequencies, at only 4-8 %. Although the percentages of cell division after 4d of PEG-fusion (17-24%) and electrofusion (19.3%) were about the same, PEG-fusion was found to be a more efficient means than electrofusion. Sodium iodoacetate at a concentration of 4-5 mM was found to efficiently inactivate the protoplasts of tamarack. All control-treated protoplasts as well as mixed cultures (unfused protoplasts) died. Tamarack protoplasts produced mature single embryos, whereas protoplasts of hybrid larches never completed embryogenesis. Some post-fusion products produced colonies and mature embryos. RAPD was used to verify the hybridity of those fusion-derived colonies and mature embryos. Of thirty-one fusion experiments between lines L2 and L5, only one produced individual colonies. Of the thirteen colonies which developed in that experiment, none yielded mature embryos. RAPD analysis of the colonies picked out from L2/L5 fusion showed DNA banding characteristics of L5. From twenty four experiments fusing L2 and L6 , there were five experiments which produced colonies. A total of two hundred and thirty nine individual colonies and nineteen single mature embryos were picked out from those L2/L6 fusions. RAPD banding profiles of eighty seven colonies and nineteen mature embryos showed DNA banding characteristics of L2 only. Tested haploid embryogenic lines (total of 6 lines; n=12) of Larix decidua initiated from megagametophyte tissue were maintained on half-strength Litvay’s medium without growth regulators. All lines had been verified as being haploid by chromosome squashes when they were initiated. Some lines have been stably haploid for only a short period of time while others have been stable for many years. Variations in chromosome numbers increased proportionately with the age of the culture. Haploids doubled their chromosome numbers. Aneuploidization occurred because of unequal separation of the chromosomes. Unusual events during mitosis such as formation of anaphase bridges, fragmentation of chromosomes, and development of long kinetochores were detected. There was a tendency of rising chromosome numbers in all lines tested over the years. Fluorescence in situ hybridization (FISH) was used to physically map highly repetitive sequences of genes coding for 18S-5.8S-26S rDNA on Larix decidua chromosomes. A karyotype of L. decidua (2n=24) was created from average relative lengths derived from the six best squashes with strong probe-target FISH signals. Hybridization of 18S-26S rDNA onto L. decidua chromosomes gave very precise locations of secondary constriction as well as unexpressed nucleolar organizer regions. In L. decidua, there were 6 major 18S-26S rDNA loci detected in 60.53% of cells (23 out of 39 cells). Five I8S-26S rDNA loci were also found but at a lower rate of 39.47%. All loci were expressed and located at the sites of secondary constriction on chromosomes 2, 4 and 7. Two extra locations of 18S-26S rDNA were mapped on aneuploid chromosomes (30 chromosomes) derived from cells of an aneuploid line (line 2110) of L. decidua. Chromosome measurement resulted in a preliminary karyotype of this line. The relative total lengths and locations of I8S-26S rDNA of standard (2n=24) chromosomes and aneuploid (2n=30) chromosomes was compared. / Graduate

Two species of Viscum, the dioecious Viscum capense ssp capense and the monoecious Viscum rotundifolium , were compared in terms of their ecology, repioductive biology and genetics in order to determine some potential selective advantages of dioecy in this genus Data was collected in such a way thiat several of the current hypotheses for the evolution of dioecy could be tested Selection for outcrossing; disruptive selection or decreased infraspecific competition; pollinator or fi ugivore attraction to tussive pollen or fruit crops and escape from seed predation were among the hyp?the~es investigated. The population structure of Viscum capense showed no evidence for disruptive selection, both in terms of host choice, and associations between plants of different sexes. Viscum rotundifolium was found to be more highly clumped than Viscum capense, which is an advantage in terms of disnerser attraction, but a disadvantage in terms of seed predation. A closer examination of the results, however, showed that the distribution of seed-bearing plants in both species was not dependant on the breeding system. Pollinator observations eliminateo the hypothesis that large polien crops would be advantageous in terms of pollinator attraction, since the pollinators were found to visit male flowers foi neotar, and not pollen. The genetic results showed that the dioecious Viscum capense and the monoecious Viscum rotundifolium did not differ in levels of genetic heterozygosity, and thus, it was assumed, that dioecy did not evolve in response to ^election * or outcrossing in this genus. These res jits also revealed a number of loci in both species which were fixed for heterozygosity, and some possible explanations for the mechanism by which these were maintained are put forward. No overwhelming selective advantage of dioecy could be determined in this case and it was hypothesized that dioecy could have been fixed in the population by chromosomal translocations which also facilitated rapid speciation, thus enabling the gene combinations for dioecy to escape elimination by selection within the original gene pool

"Cytogenetics and biology of selected representatives of the family Sphaeriidae" Mgr. ing. Tereza Kořínková Abstract of a PhD. thesis The thesis has a form of four separate articles, the full texts of which are included. Two of them were published, one was accepted and one was under revision before submission of the PhD thesis. The articles deal with cytogenetics, breeding and nutrition of selected representatives of the hermaphroditic, viviparous, primarily freshwater bivalves of the family Sphaeriidae (Mollusca: Bivalvia: Veneroida). Although various aspects of the biology of Sphaeriidae have been intensely studied for more than 100 years, many questions still remained unresolved. This thesis brings data on chromosome numbers of 11 species(10 of which have not been studied cytogenetically before) and information on the course of meiosis in two of these species (Chapter 1). Although the chromosome numbers are high (from ca. 140 to more than 240), the behaviour of chromosomes at meiosis rather corresponds to that of diploid organisms. Also the DNA contents in five selected species with high chromosome numbers (as measured by flow- cytometry) do not differ significantly from those in sphaeriids with a diploid chromosome number of 30. Such results contradict an origin of the high chromosome numbers by a...

by Wang Wei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references (leaves 154-168). / ACKNOWLEDGMENTS --- p.v / SUMMARY --- p.vi / PUBLICATIONS --- p.viii / STATEMENT OF ORIGINALITY --- p.ix / LIST OF ABBREVIATIONS --- p.x / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 --- LITERATURE REVIEW --- p.5 / Chapter 2.1 --- Chromosome --- p.6 / Chapter 2.2 --- Chromosome and Human Disease --- p.9 / Chapter 2.3 --- Chromosome and Tumour --- p.12 / Chapter 2.4 --- Chromosome in Gynaecologic Tumours --- p.17 / Chapter 2.4.1 --- Cervical tumour --- p.17 / Chapter 2.4.2 --- Uterine corpus tumour --- p.20 / Chapter 2.4.3 --- Ovarian tumour --- p.23 / Chapter 2.5 --- Methodology in cytogenetics --- p.26 / Chapter 2.5.1 --- Materials --- p.27 / Chapter 2.5.2 --- Methods of chromosome preparation --- p.28 / Chapter 2.5.3 --- Karyotype analysis --- p.34 / Chapter 2.6 --- Problems of cytogenetic analysis in solid tumour --- p.42 / Chapter CHAPTER 3 --- MATERIALS AND METHODS --- p.47 / Chapter 3.1 --- Chemicals and Solutions --- p.48 / Chapter 3.2 --- Chromosome preparation from solid gynaecologic tumours --- p.50 / Chapter 3.2.1 --- Solid tumour specimens --- p.50 / Chapter 3.2.2 --- Chromosome preparation --- p.54 / Chapter 3.3 --- Chromosome preparation from an established ovarian carcinoma cell line --- p.61 / Chapter 3.3.1 --- Origin of OCC1 cell line --- p.61 / Chapter 3.3.2 --- Characteristics of OCC1 cell line --- p.61 / Chapter 3.3.3 --- Maintaining of OCC1 cell line --- p.62 / Chapter 3.3.4 --- Chromosome preparation --- p.62 / Chapter 3.4 --- Karyotype analysis --- p.65 / Chapter CHAPTER 4 --- RESULTS --- p.66 / Chapter 4.1 --- Cytogenetic features of gynaecologic solid tumour --- p.67 / Chapter 4.1.1 --- Cervical cancer --- p.67 / Chapter 4.1.2 --- Uterine corpus cancer --- p.94 / Chapter 4.1.3 --- Ovarian cancer --- p.104 / Chapter 4.2 --- Cytogenetic features of OCC1 ovarian carcinoma cell line --- p.114 / Chapter CHAPTER 5 --- DISCUSSION --- p.123 / Chapter 5.1 --- Methodology of chromosome preparation in solid tumour --- p.124 / Chapter 5.2 --- Chromosome changes in gynaecologic solid tumour --- p.126 / Chapter 5.2.1 --- Cervical cancer --- p.126 / Chapter 5.2.2 --- Uterine corpus cancer --- p.132 / Chapter 5.2.3 --- Ovarian cancer --- p.138 / Chapter 5.2.4 --- In summary --- p.141 / Chapter 5.3 --- Chromosome changes in an OCC1 ovarian carcinoma cell line --- p.143 / Chapter CHAPTER 6 --- CONCLUSION --- p.148 / REFERENCES --- p.154

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"May 2002" Bibliography: leaves 157-176. Through the use of a variety of biochemical and genetic techniques, the importance of the nuclear localisation of PBL was examined, as well as the function of its RadECl and BRCT domains. The RadECl/BRCT domains were found to be required in the cytoplasm for cytokinesis, extending the range of function attributed to these domains. PBL was also shown to shuttle between the nucleus and the cytoplasm, providing an explanation for the observed ability of nuclear PBL to influence cytoplasmic structure.

"May 2002" / Bibliography: leaves 157-176. / x,176 leaves : ill. (some col.), plates (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Through the use of a variety of biochemical and genetic techniques, the importance of the nuclear localisation of PBL was examined, as well as the function of its RadECl and BRCT domains. The RadECl/BRCT domains were found to be required in the cytoplasm for cytokinesis, extending the range of function attributed to these domains. PBL was also shown to shuttle between the nucleus and the cytoplasm, providing an explanation for the observed ability of nuclear PBL to influence cytoplasmic structure. / Thesis (Ph.D.)--University of Adelaide, Dept. of Molecular Biosciences, 2002