Lodgepole pine (Pinus contorta Douglas ex Louden) is the most widespread pine in North America and the single most abundant tree species in British Columbia (BC). Its vast distribution, diversity and economic value make it an important species for timber harvest and subsequent reforestation. Climate change raises serious concerns over the adaptability and effective management of BC’s future forests. The majority of lodgepole pine seedlings requested for replanting are produced from seed obtained from wild stands, but the relationship between climate variation and the seed production of natural populations has yet to be assessed. The purpose of this study is to determine if variation in P. contorta seed yield is related to the climate of BC. Historical cone collection data were obtained from archived records of 1948 seedlots in 22 different natural stand seed planning zones (SPZs) of BC. Collections were made between 1963 and 2013 and seed yield (kg fresh seed/hL cone) was determined for each seedlot. First, natural variation in seed production of lodgepole pine was examined in 18 different SPZs. The Nass Skeena Transition (NST) represents a unique intersection between continental and maritime ecosystems and was found to have a significantly higher mean seed yield compared to all other zones, with the exception of Hudson Hope (HH). However, variance in seed yield for NST was found to be an order of magnitude higher than that of other SPZs, indicating that seed production in this region is exceptionally variable. These findings provide a valuable geographic baseline for the reproductive fitness of lodgepole pine, suggesting that climate adaptation and mitigation strategies for some areas of the province may need to be region-specific. In addition, the relationship between climate variation and the seed production of P. contorta in BC was evaluated. The climate of each region was described using dynamically-downscaled Global Circulation Model (GCM) and reanalysis climate output from the Canadian Regional Climate Model (CRCM). Annual, winter, and summer means were explored for each of the climate variables of interest: total precipitation (mm) and surface air temperature (°C). Temporal correlations between the mean annual seed yield anomaly and the anomaly of both climate variables were significant under a variety of climate schemes in a number of SPZs. Significant overall trends in climate variables were also captured using GCM-driven CRCM output. While these two analyses independently highlighted significant relationships between seed yield and climate, their joint implications were unclear. Shifts in the CRCM boundary conditions revealed that the results lacked robustness during the historical period, inhibiting the investigation of future projections. Ambiguous age ranges for each cone collection and temporal restrictions of the seed collection data may be partially responsible for these inconclusive results. Results from the first half of this thesis suggest that, with few exceptions, seed production is relatively stable across SPZs spanning a wide range of climate regimes. Thus, the investigation of the relationship between reproductive fitness and climate may be complicated by the extraordinary adaptability of lodgepole pine and the high genetic variation in natural populations. / Graduate

ABSTRACT Assessing the impact of herbivory on plant growth and reproduction is important to predict the success of biocontrol of invasive plants. Leaf area production is most important, as photosynthesis provides the foundation for all plant growth and fitness. High levels of defoliation generally reduce the productivity of plants. However, leaf area production fluctuates during the season and compensational growth may occur, which both complicate accurate estimations of defoliation impacts. Under field conditions the interaction with neighbouring species and the availability of soil nutrients need to be assessed in order to gauge long term effects of weed invasions on natural environments. In this thesis I have investigated seasonal leaf area dynamics in Buddleia davidii following repeated artificial defoliation, to quantify compensational leaf production and to understand the regulatory mechanisms involved. The impact of defoliation on photosynthesis, seed production, germination and nitrogen translocation patterns were analysed. Finally, possible facilitation between B. davidii and a native nitrogen fixer, Coriaria arborea, and the impact of B. davidii on soil nutrient availability were investigated. In defoliated B. davidii, increased node production (34%), leaf size (35%) and leaf longevity (12%) resulted in 52% greater total emergent leaf area in the short term. However, with time and diminishing tissue resources the compensation declined. No upregulation of photosynthesis was observed in pre-existing leaves. Compensational leaf area production occurred at the expense of reproduction but the germination capacity of individual seeds was unaffected. In B. davidii, nitrogen reserves are stored in old leaves. Thus, the defoliation-induced decline in tissue reserves led to changes in the remobilisation pattern and increased the importance of soil uptake but biomass production especially that of roots had declined significantly (39%). Slight facilitation effects from the neighbouring nitrogen fixer and VA-mycorrhizae were observed on B. davidii in the field, while its impact on soil chemistry during spring was negligible. Defoliation of B. davidii resulted in priority allocation of resources to compensational leaf growth and a concomitant reduction in flower and seed production. The compensational leaf production greatly increased the demand for nitrogen, while continued leaf removal decreased the pool of stored nitrogen. This led to changes in nitrogen remobilisation and an increased importance of root uptake. However, the significant decline in root growth will likely impair adequate nutrient uptake from the soil, which is especially important where B. davidii invades nutrient poor habitats and will increase the success of biocontrol of the species. While mycorrhizae increase nutrient accessibility for B. davidii, it is likely that the additional stress of defoliation will negate the small facilitative effects from nitrogen-fixing species like C. arborea. This research provides new insights into the mechanisms regulating leaf area dynamics at the shoot level and systemic physiological responses to defoliation in plants, such as nitrogen translocation. The compensation in leaf area production was considerable but only transitory and thus, the opportunity to alleviate effects of leaf loss though adjustment of light capture limited. However, to ascertain that photosynthesis at whole plant level does not increase after defoliation, more detailed measurements especially on new grown leaves are necessary. In general, defoliation had greatly reduced plant growth and performance so that an optimistic outlook for controlling this species can be given. Conclusions about the wider impacts of B. davidii on soil chemistry and community function will require further research.

De multiples réseaux d'agriculteurs et de jardiniers maintiennent la biodiversité cultivée dans le monde. Leurs pratiques de gestion de la santé des plantes demeurent peu étudiées. La thèse a pour objectif de caractériser l'articulation entre gestion de la biodiversité cultivée et gouvernance de la santé des plantes, se saisissant du cas d'une association d'artisans semenciers, les Croqueurs de Carottes. Elle développe une approche interdisciplinaire et transformatrice pour décrire et comprendre la gouvernance de la santé du haricot par ces acteurs, dans une perspective agroécologique. La théorie de l'acteur-réseau est mobilisée pour situer l'analyse à l’intersection entre approches agronomique et sociologique, reposant sur les données produites par un triple dispositif : expérimentations à la ferme, entretiens semi-directifs et observation participante.Nous qualifions d’in situ l'approche de la santé des plantes des Croqueurs dont l’objectif est de vivre avec les agents pathogènes potentiels. Fondées sur des interactions écologiques entre plantes et terroir, les compétences contribuant à la gestion de la santé des plantes sont distribuées à travers le système de production. Que ce soit en termes de santé ou de biodiversité, un lot de semence est l'expression d'un jeu complexe d'interactions. Il est alors difficile de délimiter des populations de plantes de leur terroir de manière précise. Par conséquent, (i) la santé des plantes ne peut être jugée qu'in situ, dans l'environnement dans lequel elles évoluent et (ii) la gouvernance de la santé des plantes doit être prise e / All over the globe, networks of seed growers are cultivating crop diversity in fields and gardens. Their contribution to the maintenance of this diversity has been studied, but research has widely left aside their management of plant health. The governance of bean health practiced by an association of artisanal seed companies, Croqueurs de Carottes, is approached as a case study in the objective of specifying how management of crop diversity and governance of plant health are articulated. Their concern for the governance of bean health is elucidated from an agroecological perspective, taking an interdisciplinary and transformative approach. Actor-network theory constitutes the backbone of the thesis, situated between agronomy and sociology and drawing upon a threefold research device: on-farm experiments, semi-directive interviews and participant observation.The Croqueurs' approach to bean health is described as in situ approach, in which plant populations are considered healthy if they are able to live with potential plant pathogens and adapt to their growing environments. Relying on ecological interactions, competences of plant health management are distributed throughout the production system. Both for plant health and crop diversity management, a seed lot is determined by a complex system of interactions. A clear boundary distinguishing plant populations from their growing environment cannot be drawn. This implies (i) that plant health must be judged upon in situ in the plants' growing environment and (ii) that the governance of plant health must be considered at the

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-14T20:27:17Z No. of bitstreams: 1 2012 - As?lio Vieira Passos.pdf: 1230136 bytes, checksum: e9c77cc513b48585810d519d2fdbf327 (MD5) / Made available in DSpace on 2017-06-14T20:27:17Z (GMT). No. of bitstreams: 1 2012 - As?lio Vieira Passos.pdf: 1230136 bytes, checksum: e9c77cc513b48585810d519d2fdbf327 (MD5) Previous issue date: 2012-08-17 / The characteristics of rusticity and multifunctionality pigeon pea (Cajanus cajan (L.) Millsp.) have been known for a long time. In small family production, units located in some settlement projects of agrarian reform, in Rio de Janeiro state, has been observed frequently this crop cultivation, and usually from seed multiplied by farmers on the spot. This study aimed to evaluate the performance of pigeon pea seeds produced for non-commercial personal use by family farmer seated agrarian reform and develop study on four harvest seasons, carried in pods "verdoengas" (yellowish green and greenish yellow) and brown, to obtain seeds non-commercial good physiological quality. The seeds acquired from family farmer seated agrarian reform were sown in 2011/02/03; seedling emergence occurred at 6 DAS, and the culture was then conveyed to the reproductive stage, when harvests were held in pods of four seasons at 140, 162, 169 and 177 DAS. The following determinations were made of: moisture content at harvest (Uc%) and storage (Ua%), average number of pods per plant, number of seeds per pod, seed yield per plant, yield, seed weigth and percentage germination and seed without heat treatment. The average Uc% was 44%, whereas the value obtained from seeds produced by brown pods was 22%, and remained Ua% average of 11% in four harvests for the two classes pods. Plants showed an average number of 62 pods / plant and pods, about four seeds / pod, the weight of a thousand seeds showed average value of 130g, with the figures derived from the seed pods were brown more high, around 142g/1000sementes, the average production of seeds per plant was 33g, the average yield was 1.300kg/ha the four harvest times, and the average of the last two harvests showed higher value, around 1.420kg/ha, the average germination rates of seeds that received heat treatment to break dormancy was 85%, while the seeds that did not receive this treatment, the average was 62%. / As caracter?sticas de rusticidade e multifuncionalidades do feijoeiro Guandu (Cajanus cajan (L.) Millsp.) s?o conhecidas h? muito tempo. Em unidades de produ??o familiar, localizadas nos projetos de assentamento de reforma agr?ria no estado do Rio de Janeiro, tem sido observado freq?entemente o cultivo dessa cultura, realizado em geral a partir de sementes multiplicadas no pr?prio s?tio, por agricultores. O presente trabalho teve como objetivo estudar o efeito de quatro ?pocas de colheita das vagens de feij?o guandu, correspondente ?s colora??es ?verdoengas? e marrons?, para obten??o de sementes n?o comerciais de m?xima qualidade fisiol?gica, produzidas para uso pr?prio em unidade de produ??o familiar. As sementes foram adquiridas mediante compra de agricultor familiar assentado da reforma agr?ria do Projeto de Assentamento Jo?o Batista Soares, e foram semeadas em 03/02/2011; a emerg?ncia das pl?ntulas ocorreu aos 6 DAS, e a cultura foi ent?o conduzida at? o est?gio reprodutivo, quando foram realizadas colheitas de vagens, aos 140, 162, 169 e 177 DAS. Foram realizadas determina??es de grau de umidade no momento da colheita (Uc%) e no armazenamento (Ua%), n?mero m?dio de vagens por planta, n?mero de sementes por vagem, produ??o de sementes por planta, produtividade, massa de mil sementes e porcentagem de germina??o com e sem tratamento t?rmico de sementes. Os seguintes resultados foram obtidos: a m?dia da Uc% foi de 44%, sendo que o valor obtido de sementes oriundas de vagem marrom foi de 22%, e a Ua% manteve valor m?dio de 11% nas quatro colheitas, para as duas classes de vagens; as plantas apresentaram um n?mero m?dio de 62 vagens/planta e as vagens, cerca de 4 sementes/vagem; a massa de mil sementes apresentou valores m?dios de 130g, sendo que os valores apresentados pelas sementes oriundas de vagens marrons foram mais elevados, em torno de 142g/1000sementes;a produ??o m?dia de sementes por planta foi de 33g; a produtividade m?dia foi de 1.300kg/ha nas quatro ?pocas de colheita, sendo que a m?dia das duas ?ltimas colheitas apresentou maior valor, em torno de 1.420kg/ha; a m?dia de germina??o das sementes que receberam tratamento t?rmico para quebra de dorm?ncia foi de 85%, enquanto nas sementes que n?o receberam esse tratamento, essa m?dia foi de 62%.

Submitted by Ubirajara Cruz (ubirajara.cruz@gmail.com) on 2017-02-01T13:59:26Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_victor_spinelli.pdf: 2531676 bytes, checksum: 0924ddb2d6d704e536893beb9a7a98e3 (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-02-01T15:38:11Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_victor_spinelli.pdf: 2531676 bytes, checksum: 0924ddb2d6d704e536893beb9a7a98e3 (MD5) / Made available in DSpace on 2017-02-01T15:38:11Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_victor_spinelli.pdf: 2531676 bytes, checksum: 0924ddb2d6d704e536893beb9a7a98e3 (MD5) Previous issue date: 2016-09-16 / Apesar do Rio Grande do Sul se destacar em área cultivada e produção de pêssegos [Prunus persica (L.) Bastch], a sua produtividade média é a mais baixa, comparada a dos outros estados produtores. Dentre os fatores associados a essa baixa produtividade, destaca-se a falta de identificação e seleção de genótipos específicos para uso como porta-enxertos. Sendo assim, os objetivos deste trabalho foram caracterizar o potencial germinativo e vigor de sementes de porta-enxertos de pessegueiro sob diferentes métodos de estratificação, analisar a correlação entre as principais características morfométricas de frutos e sementes, avaliar o efeito de doses de nitrogênio sobre o crescimento e desenvolvimento de seedlings produzidos em sacolas de plástico e identificar por meio da análise de caracteres de crescimento, genótipos contrastantes para o vigor em cinco populações de porta-enxertos de Prunus persica cultivadas no campo. Para atender aos objetivos foram realizados diversos experimentos, cujos resultados estão apresentados em quatro capítulos. No capítulo I, foram realizados três experimentos independentes. No primeiro e segundo experimento avaliou-se o efeito da estratificação das sementes com e sem endocarpo, respectivamente. Por sua vez, no terceiro, a análise do crescimento inicial dos seedlings. Verificou-se que a estratificação de sementes com endocarpo, em areia e vermiculita, por 60 dias, não influenciou no percentual de germinação das sementes, onde a porcentagem de germinação (G%) variou de 35-40% em areia para ‘Aldrighi’ e ‘Capdeboscq’, e foi de 19,5% para Okinawa. Para os demais genótipos a G% foi inferior a 5%, independente do substrato. Quando a estratificação foi realizada sem o endocarpo, a germinação foi uniforme e variou de 93% a 100%, registrando-se uma correlação significativa entre a massa das sementes e o índice de velocidade de germinação (IVG). No terceiro experimento, os seedlings de ‘Aldrighi’ e ‘Capdeboscq’ alcançaram mais rapidamente o ponto de transplantio e o maior índice de qualidade de Dickson (IQD), evidenciando-se uma associação direta dos índices NBI, SPAD e ICHL com o desenvolvimento de seedlings mais vigorosos. No capítulo II, verificou-se que frutas e sementes com maiores valores de medidas biométricas apresentam correlação positiva e forte com potencial germinativo e vigor das sementes, conforme verificado para as cultivares Aldrighi, Capdeboscq e Tsukuba 1, evidenciando que o IVG e o TMG possuem forte relação com a massa fresca das sementes, sendo características de grande interesse para selecionar genótipos com potencial para uso como porta-enxertos de Prunus persica. No capítulo III, verificou-se que os diferentes níveis de adubação com Ca(NO3)2 influenciaram no crescimento dos porta-enxertos cultivados em embalagem e que a maior dose de Ca(NO3)2, proporcionou a melhor qualidade dos seedlings, o qual foi expresso nos maiores IQD, para os três genótipos avaliados, destacando-se os seedlings da seleção ‘NR 0080412’, que também se mostraram ser mais vigorosos em relação aos demais genótipos avaliados. Por fim, no capítulo IV foram realizados dois experimentos. No primeiro experimento, verificou-se que as sementes das seleções de porta-enxertos ‘NR 0280401’, ‘NR 0080412’ e da cv. ‘Capdeboscq’ requerem menor tempo para a germinação e apresentam maior percentual de sementes germinadas. Genótipos com maturação de frutos mais precoces, devem ser armazenadas por período mais curto, devido a perda de viabilidade das sementes, conforme verificado para ‘Okinawa Roxo’. Em relação ao desempenho das populações a campo e com base nas variáveis de crescimento e suas correlações, foi possível discriminar indivíduos mais contrastantes (outliers) quanto ao vigor em quatro das cinco populações avaliadas. Considerando-se as variáveis altura de planta e diâmetro do caule, verificou-se diferenças quanto ao vigor e homogeneidade no crescimento vegetativo entre as populações de porta-enxertos avaliados nas condição de campo. As populações de seedlings derivados das cultivares ‘Capdeboscq’, ‘Tsukuba 3’ e ‘Tsukuba 1’ apresentaram homogeneidade de crescimento suficientes para serem utilizados na produção de porta-enxertos, via sementes. / In spite of Rio Grande do Sul standing out in the peach [Prunus persica (L.) Bastch] acreage and production, its average productivity is the lowest one compared to the other producer states. Among the issues which are associated with such low productivity, the lack of identification and selection of specific genotypes for rootstocks use stand out. Thus, the objectives of this study were to characterize the geminative potential and vigor of peach tree rootstocks under different stratification methods, to analyze the correlation between the main morphometric characteristics of fruits and seeds, to evaluate the effect of nitrogen doses on the growth and development of seedlings produced in plastic bags, and to identify through the growth characters analysis by contrasting to the genotypes in five Prunus persica rootstocks population, grown in the field. In order to achieve these goals, several experiments were carried out; the results are presented in four chapters. In chapter I, three independent experiments were done. In the first and second experiments the effect of stratification of seeds with or without endocarp, respectively, were evaluated. Thus, in the third one, the analysis of initial growth of seedlings was done. It was found that the stratification of seeds with endocarp, in sand and vermiculite, for 60 days, did not influence the percentage of seeds germination, where the percentage of germination (G%) ranged from 35-40% in sand to 'Aldrighi ' and 'Capdeboscq', and it was 19.5% to Okinawa. For the remaining genotypes, the G% was less than 5%, apart from the substrate. When stratification was performed without the endocarp, germination was uniform and ranged from 93% to 100%, registering a significant correlation between the mass of seeds and germination speed index (GSI). In the third experiment, seedlings of 'Aldrighi' and 'Capdeboscq' reached more quickly the point of transplanting and the Dickson quality index (DQI), showing a direct association of the nitrogen balance index (NBI), SPAD index and chlorophyll index (ICHL) with the development of more vigorous seedlings. In chapter II, it was found that fruits and seeds with higher values of biometric measures present a strong positive correlation with geminative potential and vigor of the seeds, as verified for the cultivars Aldrighi, Capdeboscq and Tsukuba 1, the GVI and the GMT have a strong relationship with the fresh mass of seeds, being features of great interest to select genotypes with potential for Prunus persica rootstocks usage. In chapter III, it was found that the different levels of fertilization with Ca(NO3)2 influenced the growth of rootstocks, cultivated into packs, and that the highest dose of Ca(NO3)2, provided the best quality of seedlings, which was expressed in the higher DQI, for the three genotypes evaluated, standing out the seedlings of the selection 'NR 0080412', that also proved to be more vigorous compared to other genotypes evaluated. Finally, in chapter IV two experiments were conducted. In the first experiment, it was found that the seeds of rootstocks selections 'NR 0280401', 'NR 0080412' and vc. 'Capdeboscq' requires less time for germination and shows a higher percentage of germinated seeds. Genotypes with earlier fruit maturation should be stored for shorter periods, due to loss the of seed viability, as checked for 'Okinawa Roxo'. Regarding the performance of field population and based on the growth variables and their correlations, it was possible to discriminate more contrasting individuals (outliers), such as the vigor in four out of the five the population evaluated. Considering the plant height and stem diameter variables, it was noticed some differences such as the vigor and homogeneity in vegetative growth between rootstocks population evaluated under the field condition. Population of seedlings derived from cultivars 'Capdeboscq', 'Tsukuba 3' and ‘Tsukuba 1' has shown enough homogeneity growth to be used in the production of rootstocks, via seeds

Made available in DSpace on 2014-08-20T13:44:46Z (GMT). No. of bitstreams: 1 dissertacao_lucas_marcolin.pdf: 1664329 bytes, checksum: d914534bea39a20ab2fb8082ed199d29 (MD5) Previous issue date: 2011-03-03 / The growing demand of consumer markets for seed quality and safety to the producer and consumer is ordering from the production sector a continuous adaptation. Food safety has become an important attribute of food quality. The traceability is in line with this view, since it integrates the entire production chain in a monitoring and certification system. Traceability programs for the productive chain are essential for logistics and management of seed production. The aim of this study was to develop and validate an efficient and effective traceability system for seed production, through a scheme of software, in order to ensure the quality and safety of the products obtained, as well as an important management tool, making the productive chain more competitive in the market. In addition to an extensive literature review, it was also made a partnership with the company Checkplant Traceability Systems LTD, in order to assist in the software scheme that they have already developed for fruit producers and many others. Furthermore, interviews with companies, researchers and seed producers from the south region helped to collect necessary data for the proposed software and to understand the obstacles and critical points of the productive chain. It was presented and tested with the users, the system screens which can work for them, containing the field part (record of field activities, its settings and reports) and the post-harvest stage (record of the activities in the Seed Processing Unit, reports, etc.), paying attention to what should be enhanced to the system implementation. It was observed that the proposed system, based on what happens with fruit producers, it is perfectly adaptable and feasible for seed producers, ensuring, besides of traceability, an important management tool / A crescente exigência dos mercados consumidores por sementes de qualidade e com segurança ao produtor e consumidor vem ordenando ao setor produtivo uma contínua adaptação. A segurança dos alimentos tem se tornado um importante atributo de qualidade alimentar. A rastreabilidade vem ao encontro com esta perspectiva, uma vez que integra toda a cadeia produtiva em um sistema de monitoramento e certificação. Programas de rastreabilidade para as etapas da cadeia produtiva são essenciais para a logística e o gerenciamento da produção de sementes. O objetivo deste estudo foi propor e validar um sistema eficiente e eficaz de rastreabilidade para a produção de sementes, por meio de um esquema de software, a fim de assegurar a qualidade e segurança dos produtos obtidos, além de uma importante ferramenta de gestão, tornando a cadeia produtiva mais competitiva no mercado. Além de extensa revisão bibliográfica, foi feita também parceria com a empresa Checkplant Sistemas de Rastreabilidade LTDA, afim de auxiliar no esquema de software que os mesmos já desenvolvem para produtores de frutas e tantos outros. Além disso, entrevistas com empresas, produtores e pesquisadores de sementes da região Sul ajudaram para a coleta de dados necessários para a proposta do software e, para entender os entraves e pontos críticos da cadeia produtiva. Foi apresentado e testado junto aos usuários as telas de sistema que podem funcionar para os mesmos, constando a parte de campo (registro de atividades de campo, suas configurações e relatórios) e a etapa pós-colheita (registro das atividades na UBS, relatórios, etc.), prestando atenção ao que deve ser aprimorado para implementação do sistema. Observou-se que a proposta de sistema, baseado no que ocorre com os produtores de frutas, é perfeitamente adaptável e viável para produtores de sementes, assegurando, além da rastreabilidade, em si, uma importante ferramenta de gestão.

No description available.

The harsh environmental and poor economic conditions of the Bolivian Altiplano require intervention to assist many of those that live there to become economically self-sufficient. We attempted to find introduced dry season reserve forage grasses that could produce enough biomass to be useful as feed for livestock, and that could also produce enough seed to distribute to farmers. While some of the grasses produced reasonable amounts of biomass, none produced seed in quantities that would be even close to being economically viable. The most likely cause of this is that the timing of resources that the grasses need to flower is very different between Bolivia and the areas from which the grasses originally came. We concluded that either the conditions under which the grasses are grown would need to be changed (i.e., earlier irrigation), or pre-adapted native species should be used. Native forbs are a critical component of any natural ecosystem, and thus should be included in wildland restoration projects. However, because the seed is currently collected by hand from the wild, it is very expensive, and this limits the ability of land managers to utilize it. A possible solution to this dilemma is for growers to commercially produce the seed and thus drive down the cost. In such a situation, it would be necessary to use herbicides to control competing weeds. We analyzed the effects of 5 herbicides on 7 species of native Utah forbs at 3 growth stages to learn which herbicides could safely be used on the test plants. We found that the plants' reaction the herbicides is largely species- and growth-stage specific.

No description available.

Na cultura da soja ocorre um grupo de percevejos sugadores de sementes, Euschistus heros (E.), Piezodorus guildinii (West.) e Nezara viridula (L.), que causam diversos distúrbios fisiológicos durante o cultivo, como o atraso da maturidade fisiológica, a retenção foliar, as perdas na produtividade e a redução do potencial fisiológico das sementes. A reação dos genótipos de soja ao estresse por percevejos é uma abordagem importante durante a etapa de melhoramento, produção de sementes e desenvolvimento de novas linhagens de soja resistente. O objetivo deste estudo foi comparar os parâmetros de produção e qualidade das sementes, e a resposta de defesa da planta dos diferentes genótipos de soja em condições de ataque de percevejos. Os ensaios foram conduzidos na Estação Experimental de Anhumas (Departamento da Genética, USP, ESALQ), com as populações de plantas de soja submetidas à condição de infestação natural dos percevejos nos anos agrícolas 2012/13 e 2013/2014, com plantas cultivadas sem o controle químico de percevejos e com o controle, em blocos casualizados com cinco repetições em cada sistema de controle. Análises dos dados foram feitas com ANOVA e MANOVA. No primeiro ano, vinte quatro genótipos de soja foram avaliados para os parâmetros agronômicos e de resistência da planta (período de formação de sementes (PFS), ciclo das plantas (Ciclo), altura da planta (AP), índice de acamamento (IA), valor agronômico (VA), número de vagem (NV), peso de mil sementes (PMS), produtividade (PROD), retenção foliar (RF) e peso de sementes boas (PSB)). No segundo ano com oito genótipos de soja, as plantas foram avaliadas pelos mesmos parâmetros agronômicos e de resistência do primeiro ano, exceto o NV e com o acréscimo da avaliação do índice percentual de danos nas vagens (IPDV) e as sementes quanto a qualidade fisiológica (germinação, envelhecimento acelerado, emergência, condutividade elétrica e tetrazólio). Além disso, as sementes e vagens de dois genótipos LQ1050 e CD215, coletadas entre os estágios R5 e R6, foram avaliadas quanto ao teor de isoflavonas em condições de estresse por percevejo no campo. Com o monitoramento da população de percevejos foi possível verificar um aumento de percevejos no PFS, sendo que a densidade populacional no ano agrícola 2012/13 foi mais alta. Para a seleção efetuada no primeiro ano agrícola 2012/13, considerou-se como principal critério o PSB mínimo e máximo para genótipos resistentes e suscetível ao percevejo para a avaliação da qualidade das sementes no segundo ano de cultivo 2013/14. Genótipos de soja com alta produtividade não garantem que os mesmos tenham resistência ao complexo de percevejos e produzam sementes com alta qualidade fisiológica. Foi verificada, nos oitos genótipos de soja do segundo ano de cultivo, variabilidade genética entre cultivares e linhagens de soja para características de qualidade fisiológica avaliada por meio dos testes de germinação e de vigor. Parâmetros utilizados para avaliação da qualidade fisiológica podem ser correlacionados com a resistência da planta ao complexo de percevejos. Coumestrol e gliocelina, compostos fitoalexinas, foram determinados nas vagens de genótipos contrastantes, mas não nas sementes. / A group of stink bugs composed by Euschistus heros (E.), Piezodorus guildinii (West.), and Nezara viridula (L.) causes several physiological disturbs in soybean during the field production, such as: delayed physiological maturity, leaf retention, yield loss, and decreased seed quality and germination potential. The reaction of soybean genotypes to stink bugs complex is an important approach for the crop breeding, seed production, and development of new resistant lines. This work aimed to compare the production and seed quality parameters, besides the plant defense under conditions of stink bugs attack. Assays were carried out at the Experimental Station of Anhumas (Department of Genetics, USP, ESALQ) with the soybean plants submitted to natural infestation by stink bugs, at 2012/13 and 2013/14 crop seasons, with absence and presence of chemical control of the insects, in a randomized block design with five replicates. The data were submitted to both ANOVA and MANOVA analysis. At the first season, 24 genotypes were evaluated as for the agronomic and plant resistance traits: seed formation period, plant life cycle, plant height, lodging index, agronomic value, number of pods per plant, mass of 1000 seeds, yield, foliar retention, and mass of healthy seeds. At the second season, eight genotypes were evaluated by the same agronomic and plant resistance traits of the first season, except the number of pods per plant. The pods damage index and seed physiological quality (germination, accelerated aging, emergence, electrical conductivity, and tetrazolium test) traits were evaluated only in the second season. The pods and seeds of LQ1050 and CD215 genotypes were collected between the R5 and R6 stages and had the isoflavones levels evaluated in conditions of stress by stink bugs attack. Through the monitoring of stink bugs population, it was possible to notice the increase of the insects in the seed formation period, with higher population density in the 2012/13 season. In the first season, the minimum and maximum masses of healthy seeds were taken as the main criterion to select susceptible and resistant genotypes, respectively, to the stink bugs attack, for the seed quality evaluation in the second season 2013/14. High yield genotypes do not ensure resistance to the stink bugs complex and, therefore, seeds with high physiological quality. We have noticed the genetic variability among the genotypes as for the physiological quality evaluated through the germination and vigor tests, at the second season. Traits used for the physiological quality can be correlated with the plant resistance to the stink bugs complex. Coumestrol and glyceollin, phytoalexin compounds, were identified in pods of the contrasting genotypes, but not in the seeds.