>Magister Scientiae - MSc / The Cape Floristic Region, situated at the southern tip of Africa, is one of the world’s most botanically diverse regions. The biodiversity of this region faces various types of threats, which can be divided into three main categories, namely increasing urbanisation, agriculture expansion, and the spread of invasive alien vegetation. It has been shown that botanically diverse areas are more prone to invasion by invasive alien plant (IAP) species. The Hawequa conservation area, in the south-western Cape, is particularly botanically diverse, such that it is very prone to aggressive invasion by IAP species. Therefore, conservation management of the Hawequa conservation area urgently need to map, prioritise and clear IAP species. Due to the topographical complexity of this mountainous area, it is not possible to map the distribution of IAP species throughout the protected area by conventional field methods. Remote sensing may be able to provide a suitable alternative for mapping. The aim of this research was to assess various image classification methods,using two types of high-resolution imagery (colour aerial photography and WorldView-2 satellite imagery), in order to map the distribution of IAP species, including small stands and individuals. Specifically, the study will focus on mapping Pinus and Acacia spp. in a study site of approximately 9 225ha in the Hawequa conservation rea. Supervised classification was performed using two different protocols, namely per-pixel and per-field. For the per-pixel classification Iterative Self-Organising Data Analyses Technique (ISODATA) was used, a method supported by ERDAS Imagine. The per-field (object-based) classification was done using fractal net evolution approach (FNEA), a method supported by eCognition. The per-pixel classification mapped the extent of Pinus and Acacia spp. in the study area as 1 205.8 ha (13%) and 80.1 ha (0.9%) respectively, and the perfield classification as 1 120.9 ha (12.1%) and 96.8 ha (1.1%) respectively. Accuracy assessments performed on the resulting thematic maps generated from these two classification methods had a kappa coefficient of 0.700 for the per-pixel classification and 0.408 for the per-field classification. Even though the overall extent of IAP species for each of these methods is similar, the reliability of the actual thematic maps is vastly different. These findings suggest that mapping IAP species (especially Pinus spp.) stands and individuals in highly diverse natural veld, the traditional per-pixel classification still proves to be the best method when using high-resolution images. In the case of Acacia spp., which often occurs along rivers, it is more difficult to distinguish them from the natural riverine vegetation. Using WorldView-2 satellite images for large areas can be very expensive (approximately R120 per km2 in 2011), but in comparison with the cost of mapping and the subsequent clearing, especially in inaccessible areas, it might be a worthwhile investment. Alternative image sources such as the high resolution digital colour infrared aerial photography must be considered as a good source for mapping IAP species in high altitude areas.

Exploring how drought influences growth, performance, and survival in different species is crucial to understanding the impacts of climate change on forest ecosystems. Here, we investigate the responses of two co-occurring pines (Pinus nigra and Pinus sylvestris) to interannual drought in east-central Spain by dendrochronological and wood anatomical features integrated with isotopic ratios of carbon (delta C-13) and oxygen (delta O-18) in tree rings. Our results showed that drought induces both species to allocate less carbon to build tracheid cell-walls but increases tracheid lumen diameters, particularly in the transition wood between early and latewood, potentially maximizing hydraulic conductivity but reducing resistance to embolism at a critical phase during the growing season. The thicker cell-wall-to-lumen ratio in P. nigra could imply that its xylem may be more resistant to bending stress and drought-induced cavitation than P. sylvestris. In contrast, the higher intrinsic water-use efficiency (iWUE) in P. sylvestris suggests that it relies more on a water-saving strategy. Our results suggest that narrower cell-walls and reduced growth under drought are not necessarily linked to increased iWUE. At our site P. nigra showed a higher growth plasticity, grew faster and was more competitive than P. sylvestris. In the long term, these sustained differences in iWUE and anatomical characters could affect forest species performance and composition, particularly under increased drought stress.

Abstract Natural selection, mutation, recombination, demographic history and chance all have a role in evolution. In natural populations, the outcome of these forces is seen as adaptations, differences between geographic varieties, and as genetic diversity in populations—both at the phenotypic and molecular levels. In this thesis I wanted to examine the roles of the evolutionary forces shaping molecular genetic diversity in trees, with emphasis on a boreal conifer, Scots pine (Pinus sylvestris). Phylogeographic history and past population size changes have a dominant role in molecular diversity of P. sylvestris. The effect of the Last Glacial Maximum (37 000–16 000) was observed in the distribution of mitochondrial DNA variation. In contrast, nuclear DNA was not much affected by the last glacial period. Instead, more ancient demographic events that took place millions of years ago can still be observed in the variation of P. sylvestris nuclear DNA. Not much evidence of positive natural selection was found in pines or trees in general. This is in contrast to strong natural selection that is observed at the phenotypic level. Positive selection is difficult to prove, especially when the genome is still affected by demographic history. Mutation–drift equilibrium may rarely be reached in tree populations.

Abstract Although microbes are generally found as endophytes in many plant tissues, the plant shoot meristems have been considered virtually sterile. Plant tissue culture, which utilizes mostly the meristems, has nevertheless given numerous references to microbial existence in these tissues. Since the bud-derived tissue cultures of Scots pine (Pinus sylvestris L.) also become easily occupied by microbes, microbial presence was considered to be one potential cause of the low regeneration capacity of tissues from mature trees. The origin of the microbes occurring in tissue cultures of buds of Scots pine was established in this study. One of the microbes, classified as Hormonema dematioides (Ascomycota), was localized in the scale tissues of a bud. Several other microbes were detected, and were associated especially with the meristematic tissues of Scots pine buds. This group was comprised of the yeast Rhodotorula minuta, and bacteria belonging to Methylobacterium spp., the Pseudomonas fluorescens subgroup, and a Mycobacterium sp. These endophytes were located particularly in the outermost cells of meristems, in the epithelial cells of resin ducts, and in the cells of the developing stem, in the vicinity of the meristems. These endophytes were less frequently found in the vascular tissue or in the intercellular spaces of cells, which are typical locations for the previously known endophytic bacteria. The meristem-associated endophytes were discovered to affect growth of pine tissues, and some of them produced substances that are suitable as precursors for phytohormone synthesis. Additionally, pure cultures of both bacterial and fungal endophytes showed antagonism in vitro against pathogens. When the correlation between the presence endophytes and the degeneration of bud-derived tissue cultures of Scots pine was studied, it was discovered that the endophytes grew uncontrollably once a tissue culture was initiated from the bud. A high level of chitinase production was also detected in these tissue cultures, which was considered to be indicative of a defense reaction. However, the endophytes were not found to colonize excessively in every tissue, but all bud-derived tissue cultures of Scots pine eventually degenerate. Therefore, it was concluded that the endophytes may not exclusively be considered responsible for the degeneration of the cultures.

The main objective of this thesis was the elucidation of the host-pathogen interaction between Pinus patula and Fusarium circinatum. This was accomplished by studying differential gene expression at the molecular level. Therefore, the first chapter reports the use of PCR-based methods in gene discovery and transcriptome analysis. The use of these techniques in the identification of novel transcripts in host-pathogen interactions addressed. These examples illustrate the differences and strong features of each technique. Chitinases are linked to defence responses in plants. In chapter tw0, the induction of chitinases in P. patula was assessed at both the protein and genetic level. Western blot analysis and enzyme activity assays indicate that chitinase enzyme is not detected a part of the defence response by P. patula after infection by F. circinatum. This was further confirmed by the lack of significant induction of two Pinus chitinase genes, LP6 and PSCHI4, as determined by RT-PCR analysis. Partial DNA sequence homologues for the LP6 and PSCH14 genes were determined and compared with a variety of plant chitinases. The low levels of detectable chitinase induction in P. patula might explain the high levels of susceptibility to the pitch canker fungus observed in seedlings of this tree. Pinus patula, the most widely planted species in South Africa, is highly susceptible to infection by F. circinatum. In chapter three, suppression subtractive hybridisation was used to elucidate the changes taking place at the molecular level early on in this interaction. Most of the identified transcripts shared homology to both biotic and abiotic stress in plants. The induction of one fragment, displaying homology to phytocyanin proteins, as followed through RT-PCR. Induction levels for this fragment differed significantly between less and more susceptible plants. Although most of the sequences isolated in this study can be Iiked to stress, most have not been linked with specific plant-pathogen interactions. This raises questions in regard to the function of these genes in host-pathogen interactions. Further research identify the function of these sequences in the defence response will be needed. These sequences can also be tested against a family of Pinus trees to ascertain if they will be useful in marker assisted selection. A molecular analysis of culture degeneration and pathogenicity of F. circinatum was attempted in chapter four. In this chapter, the differential induction of transcripts in F. circinatum was determined against several other Fusarium spp. Several of he identified fragments shared homology with stress related proteins. One transcript shared homology to a polyketide synthase, FUM5, that could be linked to fumonisin production in other Fusarium spp. ELISA detected no fumonisin production, although the FUM5 transcripts were detected. The identification of all the transcripts could provide a basis for more intensive gene discovery studies in F. circinatum and other Fusarium spp. The induction of these sequences in different isolates needs to be studied to prove their function in F. circinatum. This study also complements several other studies that studied the morphological characteristics of culture degeneration. Resistance gene analogues have been reported from a diverge set of plant species. In chapter five, degenerate PCR amplification was used to isolate TI-NBS-LRR like resistance gene analogues from a range of Pinus species. These sequences w re further characterised through comparative analysis with previously reported Pinus resistance gene analogues. Through motif analysis, several of the known conserved motifs found in NBS domains were identified and conservation with other plant NBS motifs is indicated. The P-Ioop and GLPL motifs displayed a high level of conservation on amino acid level with other plant NBS motifs. However, slight differences in several of the conserved regions were observed when the Pinus analogues were compared with Arabidopsis thaliana. The identification of differences between angiosperm and gymnosperm NBS sequences indicates that design of new degenerate probes and primers for the isolation of more ancient NBS sequences is needed. Further, phylogenetic and structural analyses of these sequences will also aid in understanding the relationship between angiosperm and gymnosperm NBS sequences. The knowledge gained from such a study will highlight the similarities between angiosperm and gymnosperm defence responses. This study represents the first detailed report on RGA in Pinus. / Thesis (PhD)--University of Pretoria, 2006. / Genetics / Unrestricted

In South Africa, the limited extent of indigenous forests accelerated the development of fast-growing introduced species plantations, on which the country is now heavily reliant for its fibre and timber products. However, the plantation forestry industry is challenged with limited freshwater resources, the need for sustainable management of introduced tree species in commercial forest production systems, and a diversity of plant ecological production factors such as soils that have to be manipulated for the purposes of increasing production capacities. Additionally, plantations are established in the limited high rainfall regions of the country and the industry’s water use has been regulated since 1972. Conversely, natural forests also provide valuable goods, however, their slow growth rates have restricted their development as commercial tree production systems. In this regard the forestry industry is continuously seeking to provide for the country’s timber and fibre needs while ensuring the provision of other ecosystem services from tree production systems. Recent developments in the forestry industry have therefore been focused on water use efficiency in current and alternative tree production systems. There is also widespread unsubstantiated belief that indigenous tree species are efficient users of water. Against this background this study sought to explore the single tree water use and water use efficiencies of introduced commercial plantation species (Pinus radiata) and that of important indigenous species (Ilex mitis, Ocotea bullata and Podocarpus latifolius) for timber and fibre production in the southern Cape region of South Africa. Single tree water use measurements were carried out for a year using the heat pulse velocity method. Growth measurements for utilisable stem wood were done on a quarterly basis for the specimen trees and growth increments over the year were determined. Single tree water use efficiency was a calculated as a function of grams of stem wood gained per litre of water transpired. Measurements of daily weather conditions and soil water content were concurrently taken during the year. The relationships between the variables that express daily climatic conditions, soil water content and daily volumes of transpired water were explored. Empirical models for the prediction of daily transpiration as a function of climate and soil water content were then developed using multiple linear regression analysis. Pinus radiata trees exhibited higher totals of volumetric transpiration than the indigenous species. The water use patterns of Pinus radiata showed higher peaks of maximum and minimum daily and seasonal water use while the indigenous species showed temperate patterns of water use throughout the year. Podocarpus latifolius attained the lowest water use efficiency in the year (0.49g/L) while Pinus radiata, Ocotea bullata and Ilex mitis had comparable water use efficiency values ranging between 1g/L to 2.50g/L. Significant positive correlations existed between climatic variables and daily sapflow volumes of the tree specimens. Daily total solar radiation showed the highest positive correlation with daily transpiration and the average value of the correlation coefficient for solar radiation and water use for all tree species was 0.70 (p < 0.001). Empirical models for predicting daily water use integrated the variables expressing plant available moisture and energy. The study enhances our understanding of single tree water use, water use efficiency, the drivers of transpiration and the applicability of such studies in developing rapid estimation techniques for water use in current and alternative South African tree production systems.

Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-01-30T10:21:42Z No. of bitstreams: 1 texto completo.pdf: 1133008 bytes, checksum: fe37e45d4deb0ccb9ad7aee50c200c24 (MD5) / Made available in DSpace on 2017-01-30T10:21:42Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1133008 bytes, checksum: fe37e45d4deb0ccb9ad7aee50c200c24 (MD5) Previous issue date: 2016-07-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A produção de polpa celulósica a partir da mistura entre fibras provenientes de dois ou mais tipos de madeiras é uma prática mundialmente conhecida. No Brasil, estas misturas na forma de cavacos são feitas industrialmente para produção de papéis cartões. Contudo, outros tipos de papéis, como os tissue, por exemplo, são também de grande importância no setor e buscam-se tecnologias para melhoria em suas características. Neste contexto, o trabalho tem como objetivo avaliar a polpação kraft da mistura de cavacos de Pinus sp. e Eucalyptus sp., a branqueabilidade, a influência das diferentes misturas nas propriedades do papel cartão produzido laboratorialmente, e as propriedades absorventes mais relevantes para o seguimento de papéis tissue. A polpação foi realizada com misturas de cavacos obtidas através da adição de 10%, base massa seca, de cavacos de pinus aos de eucalipto até a proporção máxima de 40% de pinus na mistura. Para auxiliar na interpretação dos resultados, utilizou-se uma amostra referência, que correspondeu a 100% de eucalipto. O objetivo foi atingir número kappa 20±1 e um álcali efetivo residual entre 8-10 g/L. No branqueamento, objetivou-se atingir alvura de 90% ISO através da sequência OD(EP)D. Para avaliação das propriedades dos papéis foi feito laboratorialmente papel cartão com 120 g/m 2 , utilizando-se as polpas branqueadas provenientes da curva de refino e que deu origem à camada branqueada designada como cobertura. No papel convencional de 60 g/m 2 foram avaliadas propriedades físico-mecânicas, ópticas e de absorção de líquidos voltadas para produção de tissue. Nos papéis cartões foram feitas as principais análises físico-mecânicas e de delaminação entre camadas. Os resultados referentes aos cozimentos demonstram que com o aumento da proporção de pinus em relação ao eucalipto na mistura exige-se um aumento da carga alcalina e do fator-H. Sendo o fator- H para a polpação referência de 481 e com a maior proporção de pinus de 1170. A viscosidade da polpa marrom apresentou tendência de queda com o aumento de fibras longas. O branqueamento respondeu de forma a demandas maiores de cloro ativo e menor branqueabilidade com o aumento da participação de pinus. A mistura entre cavacos de pinus e eucalipto desenvolveu nos papéis de 60 g/m 2 propriedades físico- mecânicas como módulo de elasticidade e índice de rasgo. Outras propriedades foram prejudicadas e outras não sofreram mudança significativa. Houve decréscimo nas propriedades ópticas e em certas propriedades de resistência com o aumento de cavacos de pinus na mistura. As propriedades de resistência à compressão no papel cartão indicaram piora para a resistência à compressão do anel (RCT) com maior participação de pinus na mistura e igualdade estatística entre os tratamentos para a resistência à compressão do corrugado (CMT). O índice de retenção de água foi mais baixo em polpas provenientes de misturas. / The production of pulp from the fiber mixtures of two or more kind of woods is a known practice worldwide. In Brazil these mixtures in the form of chips are made industrially for the production of paperboard. However, other types of papers as tissue paper, for example, are also of great importance in the sector and seek to technologies for improvement in its characteristics. Therefore, this study aims to evaluate the kraft pulping mixture of Pinus sp. and Eucalyptus sp. chips, the bleachability pulp produced, the influence of different blends the properties of the paperboard produced laboratory, and the most important absorbent properties for tracking tissue papers. The pulping was made with mixtures of chips obtained by the addition of 10%, dry weight basis, of pine chips in the eucalyptus up to the maximum proportion of 40% of pine in the mixture. To assist in interpreting the results, we used a sample reference, corresponding to 100% eucalyptus. The goal was to achieve kappa number 20±1 and a residual effective alkali clamped between 8-10 g/L. In bleaching, aimed to achieve whiteness of 90% ISO by following OD(EP)D. To evaluate the properties of the papers was made laboratory paper card with 120 g/m 2 , using the bleached pulp from the refining curve and giving rise to the bleached layer designated as cover. In the conventional paper of 60 g/m 2 were evaluated physico-mechanical properties and optical, absorption fluid to tissue production. In papers cards were made the main physical-mechanical analyzes and delamination between layers. The results for pulping showed that with increasing proportion relative of pine and eucalyptus relative to the mixture requires a greater H- factor. The viscosity of the brown pulp showed a downward trend with the increase of long fibers. Bleaching said so higher demands of active chlorine to pulps with the highest percentage of long fibers and also lower bleachability. A mixture of pine and eucalyptus chips developed in the paper of 60 g/m 2 physico-mechanical properties such as specific elastic modulus and tear index. Other properties were affected and others not undergone significant change. There was a decrease in optical properties. The paperboard showed improvement in certain properties of resistance with the increase of pine chips in the mixture of chips. The resistance property to the ring compression (RCT) has worsen with greater participation of pine in the mixture and the compressive strength of corrugated (CMT) observed statistical equality between treatments. The water retention value was lower in pulps from blends.

Memoria para optar al Título Profesional de Ingeniero Forestal / La madera de pino radiata, principal recurso maderero del país, es de baja durabilidad. Hongos e insectos, entre otros factores de su deterioro, son usualmente los más relevantes. Del grupo de los insectos, en particular la termita subterránea “Reticulitermes flavipes”, representa hoy la mayor preocupación, por su agresividad y avance permanente en áreas pobladas del país. El arseniato de cobre cromado (CCA) fue, por décadas, el preservante más utilizado en todo el mundo para proteger la madera, sin embargo, preocupaciones medioambientales, hace más de diez años, dieron paso a un cambio hacia otros productos. El uso de cobreazoles (CA) y en particular el de tipo B, junto con cobreazol micronizado, han sido los cambios más importantes desde entonces a nivel mundial. Su incorporación al mercado local, sin embargo, ha sido muy lenta, básicamente por costo y por no existir un marco legal que regule el uso de madera tratada con CCA. Sobre la base de los requisitos exigidos por la Australian Standard®, AS 1604.1-2012, para madera tratada con CA-B, el objetivo del estudio fue evaluar el comportamiento de madera de Pino radiata tratada con CA-B, a retenciones menores a las exigidas por la Norma Chilena, frente al ataque de hongos de pudrición y termita subterránea. Los métodos empleados fueron; “Standard Test Method for Wood Preservatives by Laboratory Soil-Block Cultures”, descrito en la ASTM Designation: D1413 − 07ɛ1 y la Norma Chilena NCh 3060.Of 2007, para el estudio con hongos y termita subterránea respectivamente. En el estudio con Lentinus lipideus, todos los grupos de retención presentaron efecto positivo en el control del hongo y diferencias estadísticamente significativas respecto a las probetas testigo. En el caso de Coriolus versicolor, solo los grupos de retención 1,4 y 1,8 kg/m3 se diferenciaron estadísticamente del testigo en el control del hongo. En el estudio contra termita subterránea, la retención necesaria de CA-B para el control de Reticulermes flavipes se ubicó entre las retenciones 1,4 y 1,8 kg/m3 (concordante con la Norma NCh 819:2012). Una retención menor en pino radiata tratado con CA-B, no pudo ser validada para el control de termita subterránea, Reticulermes flavipes.

Increments of hourly intervals of Pinus oocarpa was measured during the year 2015. The research was based in Villa Rica area, Peru. Each hour change of stem was measured by band dendrometer even climatic values like air temperature, air humidity, soil temperature and soil water availability were measured every hour too. The measured tree is part of agroforestry system of coffee, where shading tree is the main role. Measured climatic values were compared to daily changes and weekly changes of the stem. A statistically significant effect (p<0.001) was found only for the temperature and humidity of the air and their effect on changes in the strain during day and night. The above graphs have a clear effect on other values where statistical significance has not been demonstrated.

The aim of this master´s thesis was the evaluation of options that should lead to the elimination of the harmful effects of the white grubs of Melolontha hippocastani to the gradational area of Moravian Sahara (part of forest maintenance LS Stážnice, the Bzenec district). The effectiveness of chosen preparations (Force 1,5 G and Actara 25 WP) on the white grubs of Melolontha hippocastani was observed and conducted under controlled conditions in the ´container experiment´ with 380 seedlings of Pinus sylvestris. This experiment was repeatedly conducted five times over a period of 3 years. The results show that the most effective preparation against the white grubs is Actara 25 WG (200 up to 400 g/ha/600 l water) in the form of watering. This preparation in the form of spraying was ineffective. Inconsistent results were reached with the preparation Force 1,5 G. At the same time, the vertical movements of white grubs during their development stages in the soil were being observed over the period of 2015–2018. This observation took place in the drill holes of the following proportions 50 x 50 x 60–140 cm. The results confirmed that the depth of wintering of the white grubs and their movements during their vegetative state depends on the soil´s temperature and moisture, and the available sources of food to the current instar of the white grub.