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Thirteen genotypes of durum wheat were grown in two different environments in Portugal. Grain and ash mineral profile, as well as protein content, test weight, and grain ash content were evaluated. Genotype, environment, and their interaction explains the variation in the quality traits, with the environment having the highest influence. Mineral profile analysis was performed by the μ-EDXRF system: macroelements (K, P, Ca, Cl, and S) represented 99% of the total concentration detected in the grain samples, while microelements represented up to 2% of the total concentration when analyzing the ash samples (Fe, Mn, Zn, Cu, Si, Rb, Sr, and Ti). Almost every element found in the grain and ash analysis was affected by the environment. Only K and Ca in the grain had higher concentrations in the environment with water scarcity, while the concentrations of all the detected elements except for Si and Sr were higher in the ashes in this environment. Regarding the genotype, P, S, and Cu grain concentrations were not affected by the environment. The highest grain mineral concentration was found for Gingão, suggesting a better mineral uptake and/or translocation-to-grain capacity. However, regarding the technological quality, most of the genotypes presented ash content values above the maximum specified threshold.

Yellow rust caused by Puccinia striiformis f. sp. tritici, is a foliar wheat disease that cause significant yield losses in Portuguese bread and durum wheat yield, mainly in recent years. The strategies to disease control include cultural practices (crop rotation, use of balanced fertilizers, framework of planting dates), use of resistant varieties and fungicide application. The concern of modern plant breeding has been the improvement of new varieties with escape behavior to diseases and/or genetic resistance, but currently, the use of chemical produts offers a pratical and rapid response solution to combat rust outbreaks. In the present study, field experiments were conducted from 2013/2014 to 2016/2017 growing seasons to evaluate: 1) resistance levels against yellow rust in some bread and durum wheat varieties widely used by Portuguese farmers; 2) the opportunity of application of fungicide in the control of Puccinia striiformis in two stages of plant development; 3) gains obtained in each situation in yield and thousand kernel weight (TKW) compared to the control without fungicide application. This study allows to conclude that the need to use fungicide sprays it´s related not only on the carry over of rust inoculum in crop, but also of the races/strains of P. striiformis occurring in a region, the crop growth stage at time of symptom appearance and on variety level of resistance.

Thirteen genotypes of durum wheat were grown in two different environments in Portugal. Grain and ash mineral profile, as well as protein content, test weight, and grain ash content were evaluated. Genotype, environment, and their interaction explains the variation in the quality traits, with the environment having the highest influence. Mineral profile analysis was performed by the μ-EDXRF system: macroelements (K, P, Ca, Cl, and S) represented 99% of the total concentration detected in the grain samples, while microelements represented up to 2% of the total concentration when analyzing the ash samples (Fe, Mn, Zn, Cu, Si, Rb, Sr, and Ti). Almost every element found in the grain and ash analysis was affected by the environment. Only K and Ca in the grain had higher concentrations in the environment with water scarcity, while the concentrations of all the detected elements except for Si and Sr were higher in the ashes in this environment. Regarding the genotype, P, S, and Cu grain concentrations were not affected by the environment. The highest grain mineral concentration was found for Gingão, suggesting a better mineral uptake and/or translocation-to-grain capacity. However, regarding the technological quality, most of the genotypes presented ash content values above the maximum specified threshold.

Septoria leaf blotch and yellow leaf rust are the most important foliar bread wheat diseases that cause significantly yield losses in Portuguese wheat yield. In the present study, field experiments were conducted during 2013/2014 and 2014/2015 wheat growing seasons to evaluate the effect of a fungicide (Bixafen + Protioconazol) on septoria leaf blotch and yellow rust attacks on bread wheat. This evaluation was accessed by: a) checking the opportunity of fungicide application in two different phenological stages (GS 33-34) and (GS 43-44); b) analyzing the genetic resistance of each variety against the attack of these pathogens; c) finding differences on yield components (thousand kernel weight and grains/m2), grain yield and test weight when fungicide was applied one or two times, during the crop cycle. This study showed that: 1) susceptible varieties, with high levels of coefficient of infection, are beneficed with two fungicide applications, at GS 34 plus GS 47, with increases on yield components, yield/ha and test weight; 2) in moderate resistant varieties, with low levels of coefficient of infection, it is justified a preventive fungicide treatment at GS 34, to control the infectious focus and to protect leaves; 3) resistant varieties don't need a disease control, however, results showed that with two fungicide applications, grain yield and test weight increases significantly.

Yield and test weight are attributes of particular economic importance in wheat production systems and are strongly affected by environmental conditions. This study was conducted to determine the effects of sowing date and seeding rate on grain yield and test weight of fifteen bread wheat varieties and five advanced lines from Portuguese Wheat Breeding Program under irrigated Mediterranean systems. Field experiments were conducted at two locations of Southeast Portugal, during 2011/2012 growing season. Two seeding rates were compared in two different sowing dates in each location. Results showed that sowing date and seeding rate affects yield and test weight under irrigation field conditions, for Mediterranean region of Southeast Portugal, but only sowing date had significant effects among the varieties. Comparing the results obtained in the two studied locations, Beja showed, for the majority of the varieties, 3t/ha higher average yield than Elvas.

Grain quality is an essential component in wheat breeding programs since influences the commercial value of wheat. This study was conducted to determine the effects of genotype, season and sowing date on quality parameters of seventeen bread wheat commercial varieties and three advanced lines from Portuguese Wheat Breeding Program (Plant Breeding Station, Elvas, Portugal) under irrigated Mediterranean systems. Field experiments were conducted at two locations of Southeast Portugal (Elvas and Beja), during two growing seasons. At Elvas, results showed that environment (season) had highest contribution on variation of quality traits. At Beja experiments, the level of environment (season) influence decreased in relation to Elvas experiments: season was the most important factor to explain the variation of protein content and test weight, but for alveograph parameters (W and P/L ratio) it was found that genotype had higher influence. Sowing date was ever the most important factor to explain thousand kernel weight. The results confirmed that genetic potential is crucial to obtain high quality wheat but it is necessary a good environment to promote its expression.

In this thesis we study the homotopy invariant TC(X); the topological complexity of a space X. This invariant, introduced by Farber in [15], was originally motivated by a problem in Robotics; the motion planning problem. We study relations between the topological complexity of a space and its fundamental group, namely when the fundamental group is ”small”, i.e. either has small order or small cohomological dimension. We also apply the navigation functions technique introduced in [20] to the study of the topological complexity of projective and lens spaces. In particular, we introduce a class of navigation functions on projective and lens spaces. It is known ([25]) that the topological complexity of a real projective space equals one plus its immersion dimension. A similar approach to the immersion dimension of some lens spaces has been suggested in [31]. Finally, we study the topological complexity (and other invariants) of random right-angled Artin groups, i.e. the stochastic behaviour of the topological complexity of Eilenberg-MacLane spaces of type K(G, 1), where G is a right-angled Artin group associated to a random graph.

We study fundamental groups of clique complexes associated to random graphs. We establish thresholds for their cohomological and geometric dimension and torsion. We also show that in certain regime any aspherical subcomplex of a random clique complex satisfies the Whitehead conjecture, i.e. all irs subcomplexes are also aspherical.

In this paper we study topological invariants of a class of random groups. Namely, we study right angled Artin groups associated to random graphs and investigate their Betti numbers, cohomological dimension and topological complexity. The latter is a numerical homotopy invariant reflecting complexity of motion planning algorithms in robotics. We show that the topological complexity of a random right angled Artin group assumes, with probability tending to one, at most three values. We use a result of Cohen and Pruidze which expresses the topological complexity of right angled Artin groups in combinatorial terms. Our proof deals with the existence of bi-cliques in random graphs.

We establish sharp upper bounds for the topological complexity of motion planning problem in spaces with small fundamental group, i.e. when it is finite of small order or has small cohomological dimension.