The act of topping tobacco (Nicotiana tabacum L.) involves the removal of the terminal bud or inflorescence of the tobacco plant. This practice ordinarily is accomplished by manually removing the top of each tobacco plant in an entire field which is labor intensive and costly. Chemical topping utilizes sucker control products to inhibit the terminal bud and axillary bud growth without manually removing the top of the tobacco plant. There were several research objectives in order to determine the utility of a chemical topping system: 1) determine if burley tobacco could be chemically topped with currently registered suckercide products while maintaining control of subsequent sucker growth; 2) compare chemical topping to manual topping for yield and leaf quality; 3) identify burley tobacco varieties that are better suited for chemical topping systems; 4) determine the optimum plant growth stage at which chemical topping treatments should be applied; and 5) identify genes that are differentially expressed following suckercide applications. To pursue our objectives, studies were initiated investigating the optimum timing of application, ideal variety maturity, and efficacy of suckercide applications using combinations of maleic hydrazide (MH), butralin, and fatty alcohols (FA). The terminal bud was not well controlled with FA or butralin alone nor was acceptable sucker control or total yield achieved. Our data suggest that chemically topping burley tobacco with a tank mixture of MH and a local systemic may be a suitable alternative to manual topping, as total yield and leaf quality grade index were not significantly different and total TSNA and MH residues were not significantly higher compared to manual topping. The 10% button and 50% button application timings were best suited for chemical topping practices. Treatments that targeted the 10% bloom stage did not completely halt flower development, but all application timings resulted in excellent sucker control. Medium and late maturity burley varieties were found to be suitable for chemical topping methods; however, timing the suckercide application may be less difficult in later maturing varieties. Chemically topping burley tobacco at 10 to 50% button stages with a tank mixture of MH and a local systemic suckercide was found to be a suitable alternative to manual topping, and would potentially result in labor savings for burley tobacco growers. Expression of genes related to phytohormones, meristem development, cell division, DNA repair and recombination were affected following MH treatment, which likely leads to the inhibition of apical and axillary meristem development.

The United States share of the exported flue-cured tobacco market has decreased over the last decade as other countries have increased production of improved quality tobacco. Such tobacco is available at a substantially lower price than U. S. tobacco and thus desirable for the manufacture of less expensive discount cigarettes. Although world consumption of American style cigarettes is increasing, demand is not sufficient to maintain current production levels of premium quality U. S. flue-cured tobacco. Production systems that increase yields of suitable quality tobacco for discount cigarette manufacture without increasing production costs would allow tobacco to be offered competitively on the world market while maintaining current income. A study of ten management systems was conducted evaluating the influence of plant spacing, topping height, and harvest method on yield and quality of flue-cured tobacco. Leaf populations of 538,000/ha harvested once-over resulted in a 6.5%, 11.0%, 6.0%, and 13.5% increase in yield, value, price, and grade index, respectively, compared to the standard treatment. An expert panel showed no preference among systems and judged all systems acceptable in quality. A study conducted as a randomized complete block in a split plot arrangement evaluated the influence of row spacing and plant spacing on the yield and quality of flue-cured tobacco harvested once-over. Yield, value, and grade index increased while price per kg was unchanged as plant population increased. Flue-cured tobacco harvested in a single harvest produced cured leaf of acceptable quality; however, increased leaf populations are required to maintain acceptable yields. / Master of Science

Gossypium hirsutum, le coton Upland, représente plus de 95% de la fibre de coton produite annuellement dans le monde et est cultivé dans environ 40 pays. La protection des champs de coton contre l’attaque des arthropodes herbivores nécessite des quantités importantes d’insecticides de synthèse, environ 18% de la consommation mondiale en 2000, bien que cela ait beaucoup diminué grâce au coton Bt et aux programmes d’éradication de certains ravageurs. Les composés organiques volatils (COV) naturellement émis par les plantes cultivées peuvent réduire les attaques d'insectes, les COV ayant une influence sur le comportement des arthropodes herbivores et des arthropodes auxiliaires. La recherche scientifique sur les COV des plantes a beaucoup augmenté depuis deux ou trois décennies. La stimulation des émissions de COV dans les champs de coton est désormais recommandée par les entomologistes du Cirad en tant que composante de la stratégie de protection. L’écimage (topping en anglais), c'est-à-dire couper la tête des cotonniers au cours de la floraison, stimule l'émission de COV de défense, une protection écologique qui limite les risques pour la santé dus aux insecticides synthétiques, pour les agriculteurs et les personnes des environs. L'objectif de la thèse était d'améliorer nos connaissances sur les bases génétiques des émissions de COV après l’écimage. La combinaison de plusieurs disciplines telles que la bio-informatique, l'écologie chimique et la génétique moléculaire nous a permis de: 1) analyser les séquences génomiques des gènes des voies de biosynthèse des COVs terpènes et terpénoïdes et des facteurs de transcription (TF) liés à la réponse au stress, à l'aide des bases de données publiées sur les génomes de trois espèces de coton, G. raimondii, G. arboreum (cotons diploïdes) et G. hirsutum (coton tétraploïde), 2) étudier les émissions de COV par les feuilles de coton des plants de G. hirsutum en réponse à l’écimage, en capturant ces molécules en serre et en caractérisant leurs profils cinétiques par chromatographie en phase gazeuse-spectrométrie de masse (GC-MS), incluant des mesures quantitatives, et 3) étudier les modifications de l'expression ARN des plants de coton G. hirsutum après l’écimage, pour 44 gènes impliqués dans la biosynthèse des COV, et également par une comparaison du transcriptome complet au moyen d'une analyse RNA-seq. Les résultats des trois domaines scientifiques, bio-informatique, analyse chimique et expression des gènes, ont pu être liés dans notre thèse de recherche: par ex., deux des gènes initialement identifiés par la bio-informatique, correspondant à deux enzymes, TPS50 (EC: 4.2.3.106 - (E ) bêta-ocimène synthase) et TPS16 (EC: 4.2.3.111 - alpha-terpinéol synthase), ont montré une augmentation de leur expression après l’écimage, et l'analyse GC-MS montre une modification correspondante des profils d'émission de COV. Ces mêmes composés avaient déjà été caractérisés dans d'autres plantes en réponse aux dégâts d’arthropodes. Ce travail de thèse constitue une première exploration des bases génétiques des émissions défensives de COV par les cotonniers cultivés G. hirsutum. La variabilité des comportements d’expression génique observés entre les trois génotypes étudiés de coton Upland africain G. hirsutum, permet de supposer qu’une diversité génétique est présente pour les émissions défensives de COV, ce qui pourrait permettre d’améliorer et d’adapter ces mécanismes de défense naturels et leur réponse à l’écimage, dans la perspective d'une protection naturelle plus efficace des champs de coton. / Gossypium hirsutum, the Upland cotton, represents more than 95% of the cotton fiber annually produced worldwide and is grown in about 40 countries. The protection of cotton fields against the attack of herbivorous arthropods needs important quantities of synthetic insecticides, around 18% of the world consumption for the year 2000, although this decreased very much thanks to Bt cotton and eradication programs for some pests. Volatile organic compounds (VOCs) naturally emitted by crop plants can reduce insect attacks through the influence of VOCs on the behaviors of herbivorous arthropods and auxiliary arthropods. Scientific research about plant VOCs has been increasing much since two or three decades. The stimulation of VOCs emissions by cultivated cotton plants is now recommended by entomologists of CIRAD as a component of the cotton fields protection strategy. “Topping", that is, cutting the head of the cotton plants during the useful floriferous period, stimulates the emission of defense VOCs. It is an environmentally friendly method and it limits health hazards due to the use of synthetic insecticides for the farmers and the surrounding human populations. The objective of the thesis was to improve our knowledge about the genetic bases of VOCs emissions after topping. The combination of several disciplines such as bioinformatics, chemical ecology and molecular genetics allowed us to: 1) analyze the genomic sequences of VOCs genes of the terpene and terpenoid biosynthesis pathways and transcription factors (TF) related to stress response, using the published genome databases of three cotton species, G. raimondii, G. arboreum (both diploid cottons) and G. hirsutum (tetraploid cotton), 2) study the VOCs emissions by cotton leaves of G. hirsutum plants in response to topping, by capturing these molecules in greenhouse and then characterizing their kinetic profiles by means of gas-chromatography mass-spectrometry (GC-MS), with quantitative measurements, and, 3) study the modifications of the RNA expression of G. hirsutum cotton plants after topping, for genes involved in VOCs biosynthesis through quantitative PCR measurements on 44 targeted genes and also by means of a whole-transcriptome comparison through an RNA-seq analysis. The results from the three different fields, bioinformatics, chemical analysis and gene expression, could be interrelated in our research thesis: e.g., two of the genes initially identified by bioinformatics, corresponding to two enzymes, TPS50 (EC: 4.2.3.106 - (E) -beta-ocimene synthase) and TPS16 (EC: 4.2.3.111 - alpha-terpineol synthase), were shown to increase their expression after topping, while the GC-MS analysis showed an modification of the corresponding VOCs in emission profiles. These compounds have been already characterized in other organisms in response to wounds produced by herbivorous insects. This thesis work is a first exploration of the genetic bases of defensive VOCs emission by G. hirsutum cultivated cottons. The variability of genic expression behaviors observed amongst the three genotypes of African Upland cotton G. hirsutum that were studied permits to hypothesize that a genetic diversity is present for defensive VOCs emissions, that could permit to improve and adapt by breeding these natural defense mechanisms and the response to topping, in perspective of a more efficient natural protection of cotton fields.

Viticultural practices such as trunk girdling and shoot topping along with defoliation, shading and node number per vine treatments were used to alter the carbohydrate physiology of mature Chardonnay grapevines growing in the cool climate of Canterbury, New Zealand. The timing of vine defoliation in the season previous to fruiting decreased concentrations of over-wintering carbohydrate reserves (mostly starch) in both the trunks and roots of grapevines. Roots were particularly sensitive, with defoliation as early as 4 weeks after bloom in the previous season reducing starch concentrations to 1.5%Dwt at bud burst compared with 17%Dwt in non-defoliated vines. In contrast, partial vine defoliation as early as bloom in the previous season reduced root starch concentrations to 4-7%Dwt at bud burst compared with 15%Dwt in non-defoliated vines. Vine shading and trunk girdling treatments at bloom in the previous season, resulted in small reductions in root starch concentrations (16%Dwt) compared with non-shaded and non-girdled vines (19%Dwt), but shoot topping did not. Study across three growing seasons established that higher concentrations of over-wintering trunk and root carbohydrate reserves were associated with warmer and sunnier weather in the previous growing season. Individual shoot leaf removal at either the beginning or towards the end of the inflorescence initiation period, reduced shoot starch concentrations to 3-6%Dwt compared with 11 %Dwt for no leaf removal, such reductions persisted through to the following season. Shoot topping at the start of the initiation period had no effect on shoot carbohydrate accumulation, but trunk girdling temporarily increased shoot starch concentrations during the first 31 days after treatment. Reductions in over-wintering trunk and root carbohydrate reserves were associated with a reduction in inflorescences per shoot and flowers per inflorescence in the following season, the reduction as much as 50% compared with non carbohydrate stressed vines. While there were strong linear or curvilinear relationships between the concentration of starch in trunks and roots at bud burst and inflorescences per shoot and flowers per inflorescence, in case the of inflorescences per shoot, there was not an immediate cause and effect because inflorescences were initiated in the previous season. Individual shoot leaf removal during the inflorescence initiation period illustrated that leaf removal directly inhibited the initiation of inflorescences in latent buds. Shoot carbohydrate measurements showed a strong curvilinear relationship to the number of inflorescences per shoot, with a threshold starch concentration of 10-12%Dwt during the inflorescence initiation period required for a maximum number of inflorescences per shoot. Furthermore, examination of individual node positions emphasised the importance of the subtending leaf on the initiation of inflorescences within the latent bud. The number of inflorescences per shoot post bud burst was reduced on vines that were both carbohydrate reserve stressed (by previous season's defoliation) and had a high node (108) number retained per vine after winter pruning compared with little or no reduction in inflorescences per shoot on carbohydrate reserve stressed vines that had a low (20) node number per vine. The reduction in inflorescences per shoot on high node vines was associated with reduced carbohydrate reserves and reduced shoot vigour (thinner and lighter shoots). Flowers per inflorescence were reduced by as much 50% in response to lower overwintering carbohydrate reserves. Fewer flowers per inflorescence were attributed to a reduction in primary branching of the inflorescence and also a reduction in flowers per branch. Strong linear relationships between the concentrations of starch in trunks and roots and flowers per inflorescence indicate that the determination of flowers per inflorescence, unlike inflorescences per shoot, may be dependent on the level of overwintering carbohydrate reserves. This is most likely due to changes in branching of the inflorescence and individual flower formation occurring during the bud burst period. Per cent fruitset was not affected by reductions in carbohydrate reserves, so fewer inflorescences per shoot and flowers per inflorescence resulted in reduced vine yield. The findings of this thesis indicate that changes in the level of carbohydrate production and partitioning in response to a range of viticultural management practices and seasonal weather contribute to seasonal variation in grapevine flowering and yields in New Zealand's cool climate environment. The relationships between carbohydrate reserves and flowering illustrate the potential to use this information to predict grapevine flowering and forecast yields. The practical implications of this research illustrate that the viticulturist must manage grapevines not only for the current crop, but also for subsequent crops by maintaining sufficient carbohydrate reserves for balanced growth flowering and fruiting from season to season.

This work is divided in to two distinct parts. In the first part a model is developed to assess the redistribution of wave energy about an offshore array of overtopping type wave energy converters. The model is based on a classical analytical solution for diffraction about a breakwater which is modified to consider an array of dissipating, reflecting and transmitting breakwater segments, which are used to approximate an overtopping type WEC array. The model is computationally efficient and phase resolving which allows the effect of wave scattering to be investigated for large domains with high resolution irregular wave distributions. It was found that the radial waves generated by the diffraction effect spreads and defocus wave energy away from the geometrical shadow of the array. This counteracts the rate of recovery of wave energy deficit from wave directional spreading. In the second part, short-term wave forecasting for pneumatic power regulation through relief valve control is investigated at the Pico oscillating water column power plant, located in the Azores. Operational data from the Pico OWC is used to develop and critically assess a number of univariate and multivariate short-term wave forecast modelling approaches. A number of relief valve control strategies, which utilise a short-term wave forecast, are also developed and assessed using a numerical time-domain wave to wire system model. A system model for the Pico OWC is developed and validated using operational data from the Pico plant. The absolute performance potential resulting from control utilising a perfect forecast is considered, in addition to the realistic potential where a forecast, realisable in real-time, is used to drive control actions. One of the proposed relief valve control strategies is within the mechanical limitations of the existing relief valve adjustment system at Pico and this strategy was deployed in real field tests. Field test results of the plant’s performance under this strategy closely matched the simulated performance and power enhancements of up to 29% were achieved in certain sea states and the expected annual power enhancement was projected to be around 10%. Simulations of the long term plant performance under the more advanced relief valve control strategies project far greater potential for enhanced power production although these could not be tested in the field due to the project limitations.

This Master´s thesis is about ways of packages of integration circuits and modules. Especially it´s about non-hermetic types of packages. One part of this paper are basic information about packaging and aspects in design of package. Next parts are design of test samples, which are package to epoxide powder material. Based on the results of the tests method, it will propose, where the technology will be used.

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