xiv, 202 leaves : tables, graphs, photos ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Physiology, 1978

Thesis (Ph.D.) -- University of Adelaide, Department of Plant Physiology, 1978.

Thesis (Ph. D.)--Colorado State University, 2004. / Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 87-97).

Thesis (Ph. D.)--Oregon State University, 1988. / Typescript (photocopy). Includes bibliographical references (leaves 101-114). Also available on the World Wide Web.

The West Indian manatee tongue was examined macroscopically, light microscopically, and electron microscopically (scanning and transmission). The tongue was slender, muscular, and firmly fixed in the oral cavity. Only the cranial tip was free and mobile. Numerous filiform papillae were distributed over the dorsal surface of the rostral lingual region. Caudal to the filiform papillae, multiple raised, round papillae were distributed over the majority of the dorsum. Fungiform papillae were restricted to the lateral margins of the tongue. Caudally, the dorsal and lateral regions showed numerous open fossae and pits. Microscopic examination showed the majority of the lingual dorsum to be covered with a thick stratified squamous epithelium. The caudal dorsal and lateral open pits led to well-developed mucous salivary glands. Foliate papillae, located on the caudal region of the tongue, contained taste buds embedded in the epidermis. Glands within the foliate papillae were mostly mucous, though some seromucous glands were evident. Throughout the tongue, striated muscle was abundant below the epidermis. Blood vessels, lymph channels, and nerve fibers were freely distributed throughout the intermuscular stroma. Nerve fibers reacted positively with neuron specific enolase antibody throughout the lingual structure, including nerve bundles, muscle bundles, glands, and taste buds. Electron microscopy revealed cytoplasmic vacuoles juxtaposed to the nucleus in the stratum spinosum of the foliate papillary region. / Master of Science

Thesis (PhD)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Various experiments were undertaken over a period of five years to investigate the feasibility of initiating a large-scale programme of controlled apple breeding and selection for the improvement of climatic adaptation, using budbreak number (NB) as a practical criterion of selection. NB is preferred to time of budbreak as sole criterion on the grounds that early budbreak is associated with low NB under local conditions. Variation within and between adult and juvenile seedling families was investigated and the genetic control of the traits involved was assessed, as well as direct and correlated responses to selection. In initial experiments different rating criteria for NB as measure of chilling requirement were tested in association with vegetative and reproductive budbreak time and flowering duration, viz, a classification index based on number and distribution of budbreak (pDS grade), an index where shoot length with increased budbreak was included in the index calculation (pDS index) and bud break number expressed as number per 100 cm of shoot length (NB index). Variance analysis (ANOVA and Variance component analyses) detected significant variation within seedling families for budbreak time and NB, but estimates of genetic components of variance between families were generally low. High genetic variance among seedlings within families is most likely due to the high level of heterozygosity in the parental cultivars as is characteristic of vegetatively propagated crops. Intra-class correlation coefficients for clones within and between families indicate moderate genetic determination for NB with broad sense heritabilities around 30 percent. Realized heritabilities calculated from response to two-way truncation selection were between 40 and 60 percent. For budbreak time (reproductive and vegetative), the broad sense heritability averaged around 75 and 69 percent, respectively, indicating a high degree of genetic determination. Significant response to selection for NB of one-year-old shoots of young seedlings and from seedlings grown into adult trees showed that pre-selection for increased budbreak successfully identified seedlings genetically inclined to more and better distribution of budbreak within a set time of 21 days after initial budbreak. Correlated responses indicated additional advantages of practical and horticultural value, viz, uniformity and position of bud break, and the number and length of side shoots. In general, it is concluded from responses to two-way selection that utilizable genetic variance in NB is present within seedling families and thus that selection may successfully be applied as an early screening method for increased budbreak in adult trees. The NB index of intact one-year-old shoots under prevailing sub-optimal winter conditions is therefore proposed as criterion of selection for improvement of climatic adaptation, and combined selection utilizing genetic variation between and within crosses as the selection method. / AFRIKAANSE OPSOMMING: Verskeie proewe is oor 'n periode van vyf jaar uitgevoer om die toepaslikheid van 'n grootskaalse appelteel- en seleksieprogram vir die verbetering van klimaatsaanpasbaarheid te ondersoek met 'aantal knopbreke' (NB) as praktiese seleksiekriterium. NB word verkies bo tyd van knopbreek op grond daarvan dat vroeë knopbreek onder plaaslike toestande met lae NB gepaard gaan. Variasie binne en tussen volwasse en jong saailingfamilies en die genetiese beheer van die betrokke eienskappe is ondersoek, asook direkte en gekoreleerde seleksieresponsie. In die aanvangs-eksperimente is verskillende kriteria vir die kwantifisering van aantal knopbreke getoets as potensiële maatstawwe van die inherente kouebehoefte in appelsaailinge. Die tyd van vegetatiewe en reproduktiewe knopbreek en blomperiode is ook getoets. Die volgende indekse is gebruik: 'n klassifikasie-indeks om die aantal en verspreiding van knopbreke te beskryf (pDS graad), 'n indeks waar die lootlengte, met verhoogde aantal knopbreke, ingesluit is in die berekening van die indekswaarde (PDS indeks), en knopbreke uitgedruk as die aantal per 100 cm lootlengte (NB indeks). Variansie analise (ANOVA en variansie komponent analise) het betekenisvolle variasie binne saailingfamilies aangetoon vir tyd van, en aantal knopbreke. Ramings van genetiese komponente van variansie tussen families was relatief klein. Hoë genetiese variansie tussen saailinge binne families is waarskynlik te wyte aan die hoë vlak van heterosigositeit in die ouergenotipes, wat kenmerkend is van gewasse wat vegetatief voortgeplant word. Intraklas korrelasie koëffisiënte vir klone tussen en binne families het gedui op 'n middelmatige oorerflikheid in die breë sin (ongeveer 30 persent) vir aantal knopbreke. Verhaalde oorerflikhede wat bereken is vanaf responsie op twee-rigting atknottingsseleksie was tussen 40 en 60 persent. Vir tyd van knopbreek (vegetatief en reproduktief) was die breësin oorerflikhede ongeveer 75 en 69 persent, onderskeidelik, wat aanduidend is van 'n hoë graad van genetiese bepaling. Betekenisvolle responsie op seleksie vir NB van jong saailinge en saailingbome wat volwassenheid bereik het toon dat pre-seleksie vir knopbreke saailinge kan identifiseer wat geneties meer knopbreke en 'n beter verspreiding van knoppe binne 'n periode van 21 dae na die eerste knopbreek lewer. Gekorreleerde responsie op seleksie toon 'n addisionele voordeel van praktiese en tuinboukundige belang, naamlik, meer en langer sylote. In opsomming kan dit gestel word dat responsie op twee-rigting seleksie bruikbare genetiese variasie vir NB binne saailingfamilies ontgin het en dat seleksie vir verhoogde aantal knopbreke suksesvol toegepas kan word. Die NB indeks op een-jaar-oue hout word dus voorgestel as seleksiekriterium vir verbetering van klimaatsaanpasbaarheid onder plaaslike sub-optimale wintertoestande, en gekombineerde seleksie "combined selection" wat genetiese variasie binne en tussen kruisings benut as seleksiemetode.

No description available.

Proefschrift--Utrecht. / "Stellingen": p. [143]-144. "Litteratuuroverzicht": p. [129]-137.