Artificial inoculations in the Cupressaceae proved that <I>Seiridium cardinale</I> was more virulent than <I>S.cupressi</I> and <I>S.unicorne. Cupressus macrocarpa</I> was found to be highly susceptible to <I>Seiridium</I> canker, <I>C.sempervirens</I> very susceptible, while <I>C.torulosa</I> and <I>C.arizonica</I> were moderately susceptible. <I>Chamaecyparis lawsoniana</I> was highly resistant to <I>S.cardinale</I>, but very susceptible to <I>S.unicorne</I> and moderately susceptible to <I>S.cupressi</I>. Intraspecific variation in susceptibility to <I>S.cardinale</I> was found in <I>C.sempervirens. S.cupressi</I> was more pathogenic than <I>S.unicorne</I> on <I>C.macrocarpa, C.arizonica</I> and <I>C.torulosa</I>, whereas it was less pathogenic on <I>C.sempervirens</I>. Mature bark proved to be more resistant to <I>Seiridium</I> canker than young bark. Low variability in pathogenicity of <I>S.cardinale</I> was found, with only one isolate out of eight proving to be a weaker pathogen. Histological examination of bark of cypress seedlings following infection with <I>S.cardinale</I> revealed the formation of strong necrophylactic periderm as an important resistance mechanism against <I>Seiridium</I> attack, and was particularly marked in <I>C.lawsoniana</I>. Strong necrophylactic periderms were detected in resistant and tolerant clones of <I>C.sempervirens</I>, whereas weak or a series of easily re-invaded ones were found in susceptible clones. Variations in pathogenicity of <I>Seiridium</I> in <I>in vitro</I> inoculations of micropropagated cypress shoots paralleled results found in the glasshouse. Wounding of micropropagated shoots significantly increased the size of lesions caused by all three <I>Seiridium</I> spp. In axenic conditions, hyphae of <I>Seiridium</I> spp. penetrated host tissues through stomatal apertures or directly through the cuticle. Under these conditions, infected tissues of <I>C.lawsoniana</I> formed ligno-suberized barriers as a result of fungal invasion, whereas those of <I>C.sempervirens</I> did not.

Thesis (M.Sc.) -- University of Adelaide, Dept. of Botany, 1979.

Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library. / Tasmanian fossil sites are rich in Cupressaceae genera and species and yet only three genera (Artrotaxis, Diselma, Callitris) survive there today. The aim of this study is the identification of some new and previously undescribed Cupressacea-related Tasmanian fossils. This is achieved by comprehensive morphological reviews of the foliage and cones (ovulate and pollen) of six extant Southern Hemisphere Cupressaceae genera. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1277497 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007

Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library. / Tasmanian fossil sites are rich in Cupressaceae genera and species and yet only three genera (Artrotaxis, Diselma, Callitris) survive there today. The aim of this study is the identification of some new and previously undescribed Cupressacea-related Tasmanian fossils. This is achieved by comprehensive morphological reviews of the foliage and cones (ovulate and pollen) of six extant Southern Hemisphere Cupressaceae genera. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1277497 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2007

This dissertation comprises a series of studies designed to explore the associations between plants and the endophytic fungi they harbor in their above-ground tissues. By viewing endophyte diversity in ecologically and economically important hosts through the lenses of phylogenetic biology, microbiology, and biotechnology, this body of work links plant ecology with newly discovered symbiotic units comprised of endophytic fungi and the bacteria that inhabit them.This work begins with a large-scale survey of endophytic fungi from native and non-native Cupressaceae in Arizona and North Carolina. After isolating over 400 strains of endophytes, I inferred the evolutionary relationships among these fungi using both Bayesian and parsimony analyses. In addition to showing that native and introduced plants contained different endophytes, I found that the endophytes themselves harbor additional microbial symbionts, recovering members of the beta- and gamma-proteobacterial orders Burkholderiales, Xanthomonadales, and Enterobacteriales and numerous novel, previously uncultured bacteria. This work finds that phylogenetically diverse bacterial endosymbionts occur within living hyphae of multiple major lineages of ascomycetous endophytes.A focus on 29 fungal/bacterial associations revealed that bacterial and fungal phylogenies are incongruent with each other and did not reflect the phylogenetic relationships of host plants. Instead, both endophyte and bacterial assemblages were strongly structured by geography, consistent with local horizontal transmission. Endophytes could be cured of their bacterial endosymbionts using antibiotics, providing a tractable experimental system for comparisons of growth and metabolite production under varying conditions. Studies of seven focal fungal/bacterial pairs showed that bacteria could significantly alter growth of fungi at different nutrient and temperature levels in vitro, and that different members of the same bacterial lineages interact with different fungi in different ways.Focusing on one isolate, I then describe for the first time the production of indole-3-acetic acid (IAA) by a non-pathogenic, foliar endophytic fungus (Pestalotiopsis neglecta), suggesting a potential benefit to the host plant harboring this fungus. I show that this fungus is inhabited by an endohyphal bacterium (Luteibacter sp.) and demonstrate that mycelium containing this bacterium produces significantly more IAA in vitro than the fungus alone. I predict that the general biochemical pathway used by the fungal-endohyphal complex is L-tryptophan-dependent and measure effects of IAA production in vivo, focusing on root and shoot growth in tomato seedlings.

Twenty-one fossil foliage, identified as Fokienia shengxianensis sp. nov. (Cupressaceae), were collected from the upper Miocene Shengxian Formation in Tiantai and Ninghai counties, Zhejiang Province of eastern China. These fossils can likely be distinguished from other extant genera in the family Cupressaceae s.l. except Fokienia by leaf external morphology alone. Foliar cuticular comparison with the only modern species in this genus, Fokienia hodginsii Henry et Thomas, further suggests that the present fossil species closely resembles the modern counterpart. Paleoecologically, the occurrence of Fokienia from the Shengxian Formation appears to support that the fossil site was covered by subtropical evergreen broad-leaved forest and under warm and humid conditions during the late Miocene, consistent with evidence from previously published fossil plants.

Inaug.-diss.--Basel. / Curriculum vitae. "Es lag uns hauptsãchlich daran, die entwicklung der medizinischen kenntnisse ... kennen zu lernen."--Einleitung. "Biographisches register": p. 151-160. "Literaturverzeichnis"; p. 161-171.

Western redcedar (Thuja plicata Donn ex D. Don; redcedar), an indeterminate conifer in the Cupressaceae family, is vulnerable to maladaptation in the face of climate change. Assisted gene flow is one mitigation strategy and involves human-mediated migration of populations, where the projected climate of the area of deployment matches the source climate of the population. Despite the overall projections of warmer temperatures globally, in British Columbia (B.C.), the risk of seasonal frost events will remain and therefore the potential for cold damage and mortality of redcedar exists if the newly migrated populations cannot withstand these freezing events. Knowledge of redcedar's ability to withstand freezing temperatures (cold hardiness) is therefore crucial. Redcedar, like many Cupressaceae species, produces and accumulates the purple-coloured carotenoid rhodoxanthin during the winter. This was hypothesized to be correlated with cold hardiness. Assessment of variation in overall, fall and spring cold hardiness and associated rhodoxanthin concentrations were done through repeated, seasonal freeze testing of clonal grafts originating from across the range of redcedar, and seedling progeny from a subset of these clones. Cold damage was quantified using electrolyte leakage and rhodoxanthin concentrations were quantified using high performance liquid chromatography. Cold hardiness and rhodoxanthin were individually modelled using univariate and bivariate mixed effect models with clone/family as a random effect. Model outputs were compared to climatic variables associated with clonal origin to test for climatic relationships. This study found genetic variation in cold hardiness of redcedar with weak climatic clines. This indicates that assisted gene flow of redcedar should be done on a case-by-case basis, with no need for a climatic threshold. Overall heritability of cold hardiness was 0.17 ± 0.03. Novel findings included the positive genetic correlation between fall and spring cold hardiness (0.55 ± 0.33); lack of reciprocal or parental effect for overall cold hardiness; and weak climatic relationships between cold hardiness and predominantly temperature, with the strongest correlation between number of frost-free days in January (0.38, p < 0.01) in the location of origin and cold hardiness. All findings related to rhodoxanthin were novel. Rhodoxanthin varied with family/provenance and season with heritabilities of 0.30 ± 0.09 in fall, 0.42 ± 0.09 in winter and 0.28 ± 0.09 in spring. Winter and spring rhodoxanthin concentrations were phenotypically correlated (0.50, p < 0.01) and genetically correlated (0.76 ± 0.14). Surprisingly, rhodoxanthin was not detected in clonal grafts of redcedar in any season. Results also indicate that rhodoxanthin cannot be used to estimate cold hardiness. The absence of rhodoxanthin in the clonal grafts compared to the seedlings suggests that plant age impacts rhodoxanthin accumulation. / Graduate / 2021-12-14

Typed article regarding tree species found in Graaff-Reinet, East Cape Midlands. Trees mentioned include Erythrina caffra, cypresses and Yellowwood.

Juniper trees (Juniperus osteosperma, J. monosperma, J. deppeana and J. scopulorum) grow under widely varying climatic and edaphic conditions throughout the American southwest. This study is chiefly concerned with a test of the climatic response in the partitioning of the stable isotopes of carbon in such trees. The relationships developed here, for example, might be used to extract paleoclimatic information from ancient juniper samples preserved in cave middens. In order to test for a climatic response in the leaf cellulose δ¹³C values, leaves from a total of 29 trees were sampled in the immediate vicinity of 9 meteorological stations across the state of Arizona. Care was taken to insure that 22 of the trees experienced only the temperature and precipitation values reflected by their site meteorological stations. As a cross-check, 7 trees exposed to temperature and/or precipitation levels clearly deviant from their site averages were also sampled. In general, each tree was sampled at four places, approximately 2 m above the ground. All leaf samples were reduced to cellulose (holocellulose) before combustion and analysis for their δ¹³C value. The δ¹³C value for each site was derived from an average of 2 to 4 trees per site, the value of each tree being the average of its individual samples. The one sigma 13C variation found between trees at any given site is ±0.38‰; within a single tree, ±0.36‰; and for repeat combustions, ±0.20‰. The δ¹³C values of the juniper sites were regressed against the temperature and precipitation of the individual months and running averages of months across the year using polynomial, multiple regression analysis. Temperature and precipitation were entered as separate variables in a general multiple regression model and also as a combined, single variable (T /P) in a more specific approach. The pattern formed by the multiple correlation coefficients, when plotted by months across the year, closely follows the seasonal variations in photosynthetic activity. Cellulose δ¹³C values have minimum correlation with temperature and precipitation (considered jointly) during summer months and maximum correlation during spring months. For an individual month, the temperature and precipitation (jointly) of April correlated at the highest level with a multiple adj. R = 0.994 and an F = 166; for a maximum seasonal response, March-May reached a multiple adj. R = 0.985, F = 66. The results using the combined, single variable (T /P) were nearly equivalent for the same months: April's adj. R = 0.957, F = 45; March-May's adj. R = 0.985 with an F = 132. The ability of T and P as independent predictors is considerably less than their ability in combination; e.g., 13C g(T) for March-May has an adj. R = 0.80 and 6 13C = h(P) has an adj. R = -0.67 compared to their in- concert adj. R value of 0.985. The results of this study, therefore, strongly support a high degree of climatic sensitivity in the partitioning of the stable isotopes of carbon in juniper leaf cellulose: the correlation coefficients and their F statistics are sufficiently high to consider temperature and precipitation (acting jointly) as accurate predictors of cellulose δ¹³C values in the system studied.