This study investigated the potential of companion planting as a strategy to aid in the management of Helicoverpa armigera in tomato and capsicum cropping systems. The investigaitons showed that a companion planting type system is unlikely to confer any benefits to the management of H. armigera in these crops. The project has contributed to the understanding of H. armigera host selection and how the pest responds to a diversified environment. Companion planting and vegetational diversity are strategies for reducing pest incidence on crops. Many theories have been devised to explain how introducing more than one plant species to a cropping space may reduce the incidence of a pest. Five ecological theories formed the basis of experiments in this study: The resource concentration hypothesis - Herbivores are more likely to find and remain on hosts that are growing in dense or nearly pure stands (Root, 1973). Associational resistance/Plant apparency - Crop plants grown as monocultures are more apparent to herbivorous insects than plants in diverse natural systems (Tahvanainen and Root, 1972). Trap cropping – the use of plants within a cropping area to attract oviposition away from the main crop (Banks and Ekbom, 1999). The ability of H. armigera to learn in regard to host seleciton (Cunningham et al., 1998a). The natural enemies hypothesis - generalist and specialist natural enemies are expected to be more abundant in diverse rather than simple systems (Root, 1973) A tall variety of sorghum (the forage variety Chopper) was tested for its ability to disrupt host location. Sorghum was planted around plots of tomatoes to act as a screen to disrupt visual cues for host location by Helicoverpa spp. No difference was found in egg numbers on tomatoes with or without sorghum companions. However, significantly higher numbers of Helicoverpa spp. larvae were found in the sorghum at flowering than in the tomatoes. This suggested the sorghum was acting as a trap crop, diverting oviposition away from the tomato crop. However, due to a short period of flowering and therefore peak attractiveness to H. armigera, sorghum was not considered to be a suitable companion plant for inclusion in commercial tomato production systems. A host preference study was conducted to determine the preferences of H. armigera for crop plants and possible companions in the hope of finding a suitable trap crop species. Tomatoes were shown to be a highly preferred plant making it difficult to find a compatible trap crop species that would be more attractive than the main crop. However, capsicums were less prefered and therefore more suitable for this type of experimentation. Marigolds were also found to be a highly preferred plant and formed the basis for further investigations into trap cropping systems. Field experiments were conducted in successive years in two geographical locations to assess the suitability of marigolds as a trap crop for capsicums in a field situation. However, in both years H. armigera incidence was extremely and unusually low leading to inconclusive results. A glasshouse experiment was performed to assess if the ratio of capsicum plants to marigolds plants had an effect on which species H. armigera would choose for oviposition. It was found that as more capsicum plants were introduced, moths became less likely to oviposit on the supposedly more preferred marigold plant. The diminishing attractiveness of a more preferred host in the presence of other hosts is a new observation of H. armigera behaviour. This result suggests that marigolds would be unlikely to be a successful trap crop in a field situation. The ability of H. armigera to learn in regard to host selection and the influence of this on host selection in the field was investigated. No evidence of learning was found. This was the first study investigating the effect of learning in a field situation; previously the behaviour had only been investigated in a laboratory situation (Cunningham, et al. 1998a). The ability of the Australian assassin bug, Pristhesancus plagipennis (Walker) (Hemiptera: Reduviidae) to predate H. armigera larvae on capsicum plants was investigated. This predator has been sucessfully been used for H. armigera management in cotton (Grundy, 2000b), but had not been investigated in horticultural crops. Significant reductions in larvae were achieved in treatments where assassin bugs were introduced. This predator warrants further investigation for inclusion in commercial integrated pest managment programs for capsicums. Pest repellent plants were also considered. Previous to this study, very little research work had been conducted on repellent plants for H. armigera. The herbs investigated were catnip (Nepta cataria), tansy (Tanacetum vulgare), basil (Ocium basilicum) and coriander (Coriander sativum). An olfactometer system was designed and built to test H. armigera moths’ responses to odours from the herbs. Glasshouse experiments were also conducted. No repellent activity was recorded with any of the herbs tested. The results of this study support the theory that Helicoverpa spp. employ a strategy of passive host selection as suggested by Firempong (1986). This means that all available plants in an area may be oviposited on with successful ovipostion and larval development leading to the future utilisation of a species as a host plant. The implication of this finding is that in-field trap cropping is unlikely to be a successful strategy for reducing H. armigera oviposition in tomato or capsicum production systems in Australia. In cotton crops in Australia, trap cropping is used as part of an area wide management strategy and aims to reduce the total Helicoverpa spp. population of a region. Such a strategy may also be successful in horticultural crops but only with the full participation of the growers of all crops that are attractive to H. armigera in a horticultural growing region. Due to the diverse nature of horticultural production this may be a difficult task.

CNPq; Capes / A Integração Lavoura Pecuária (ILP) é um sistema com destaque na recuperação de áreas degradadas, visando a maximizar o uso do solo ao produzir maiores quantidades de biomassa,pois possibilita o cultivo de diferentes espécies vegetais na mesma área, no tempo e/ou espaço. O consórcio entre milho e forrageiras se destaca na ILP, pois garante ao produtor diversidade na renda, garantindo a sustentabilidade do sistema. Nesse contexto, objetivou-se, através deste trabalho, avaliar uma alternativa de consórcio para a região sudoeste do Paraná, com forrageiras consorciadas com milho, em clima subtropical. O plantio do milho consorciado com B. Ruziziensis, B. Brizantha cv. Piatã, e Panicum Maximum cv. Aruana, ocorreu no início do mês de outubro de 2014, dispostos em quatro repetições. Avaliou-se a produção de matéria seca (MS) de milho no ponto de ensilagem, o total de biomassa das forrageiras, componentes de rendimento, produtividade de grãos do milho e nitrogênio no tecido de ambas as espécies. Na produtividade de silagem milho não houve diferença significativa entre os tratamentos, já no rendimento de grãos, o tratamento com menor produção foi Milho + B. ruziziensis com 5.486,88 kg ha-1. Na produção de silagem de milho + forrageira, o tratamento Milho + B. ruziziensis apresent ou maior produção de MS, 21.502,5 kg ha-1, seguido pelo tratamento Milho + B. brizantha cv. Piatã com 21.192,6 kg ha-1 de MS, e o tratamento Milho + Aruana com a menor produção. Observou-se que quanto maior a produtividade de biomassa da forrageira, menor foi o rendimento de grãos nos tratamentos consorciados com forrageiras. Há maior rendimento na produção de silagem quando há maior incremento da forrageira. Nas três épocas de corte da forrageira, o tratamento Milho+ B. Ruziziensis obteve maior rendimento de biomassa. Na questão competição por Nitrogênio, os resultados não foram significativos para ambos os tratamentos quando comparados com o milho solteiro, ou seja, não houve competição das forrageiras com a cultura do milho pelo nutriente. O tratamento com P. Maximum cv. Aruana obteve um menor índice na produção de biomassa, mas na questão proteína bruta, foi a com maior percentual avaliado 165,6 g kg-1, levando o produtor a ter boas alternativas quanto ao seu objetivo principal. Na questão de grande produção de biomassa, o tratamento Milho+ B. Ruziziensis apresentou-se como uma boa alternativa para incrementação de palhada ao solo e pecuária de corte. No teor de proteína, o tratamento Milho+ P. Maximum cv. Aruana se destaca, sendo ótimo para a pecuária leiteira, de grande destaque na região Sudoeste do Paraná. / Crop-animal System is a system with emphasis on the recovery of degraded areas and aims to maximize the use of land to produce greater quantities of biomass. It allows the cultivation of different plant species in the same area, time and / or space. The combination of corn and forage is important in this system. It ensures to the producer diversity in the income and guarantee the system's sustainability. In this context, the aim of this work is to evaluate an alternative combination of corn and forage in the southwest of Paraná, in a subtropical climate.The plantation of crop with Brachiaria Ruziziensis, Brachiaria Brizantha cv. Piatã,and Panicum Macimum cv. Aruana, was at the beginning of October 2014. The experiment was arranged in four repetitions. We evaluated the production of dry matter (DM) of maize silage point, total biomass, the forage yield components for corn productivity and nitrogen in the tissue of both species. Productivity of corn silage there was no significant difference between the treatments, but, Corn + B. Ruziziensis in the grain yield it was the treatment with lower production, with only 5486.88 kg ha-1. In the production of corn silage + forage, treatment Corn + B. Ruziziensis showed higher DM production, 21,502.5 kg ha-1, followed by treatment Corn + B. Brizantha cv. Piatã with 21,192.6 kg ha-1 DM, and treatment Corn + P. Maximum cv. Aruana with lower production. It was observed that the higher the forage biomass productivity, the smaller the grain yield in forage consortium treatments. There is a greater efficiency in the production of silage when there is a greater increase in forage. In the three forage cutting times, Corn + B. Ruziziensis treatment obtained higher biomass yield. In the case of nitrogen competition, the results were not significant for both treatments compared with single corn, there was no competition from forage with the corn crop by nutrient. The P. Maximum cv. Aruana got a lower rate in the production of biomass, but the question crude protein was the highest percentages estimated 165.6 g kg-1, leading the producer to have good alternatives as their primary goal. In the case of biomass, the Corn+ B.Ruziziensis treatment would be a good alternative to incrementing straw to the soil and also for beef cattle activity. On protein, Corn fits+ P. Maximum cv. Aruana, it’s great for dairy farming that has great prominence in the Paraná Southwest region.

CNPq; Capes / A Integração Lavoura Pecuária (ILP) é um sistema com destaque na recuperação de áreas degradadas, visando a maximizar o uso do solo ao produzir maiores quantidades de biomassa,pois possibilita o cultivo de diferentes espécies vegetais na mesma área, no tempo e/ou espaço. O consórcio entre milho e forrageiras se destaca na ILP, pois garante ao produtor diversidade na renda, garantindo a sustentabilidade do sistema. Nesse contexto, objetivou-se, através deste trabalho, avaliar uma alternativa de consórcio para a região sudoeste do Paraná, com forrageiras consorciadas com milho, em clima subtropical. O plantio do milho consorciado com B. Ruziziensis, B. Brizantha cv. Piatã, e Panicum Maximum cv. Aruana, ocorreu no início do mês de outubro de 2014, dispostos em quatro repetições. Avaliou-se a produção de matéria seca (MS) de milho no ponto de ensilagem, o total de biomassa das forrageiras, componentes de rendimento, produtividade de grãos do milho e nitrogênio no tecido de ambas as espécies. Na produtividade de silagem milho não houve diferença significativa entre os tratamentos, já no rendimento de grãos, o tratamento com menor produção foi Milho + B. ruziziensis com 5.486,88 kg ha-1. Na produção de silagem de milho + forrageira, o tratamento Milho + B. ruziziensis apresent ou maior produção de MS, 21.502,5 kg ha-1, seguido pelo tratamento Milho + B. brizantha cv. Piatã com 21.192,6 kg ha-1 de MS, e o tratamento Milho + Aruana com a menor produção. Observou-se que quanto maior a produtividade de biomassa da forrageira, menor foi o rendimento de grãos nos tratamentos consorciados com forrageiras. Há maior rendimento na produção de silagem quando há maior incremento da forrageira. Nas três épocas de corte da forrageira, o tratamento Milho+ B. Ruziziensis obteve maior rendimento de biomassa. Na questão competição por Nitrogênio, os resultados não foram significativos para ambos os tratamentos quando comparados com o milho solteiro, ou seja, não houve competição das forrageiras com a cultura do milho pelo nutriente. O tratamento com P. Maximum cv. Aruana obteve um menor índice na produção de biomassa, mas na questão proteína bruta, foi a com maior percentual avaliado 165,6 g kg-1, levando o produtor a ter boas alternativas quanto ao seu objetivo principal. Na questão de grande produção de biomassa, o tratamento Milho+ B. Ruziziensis apresentou-se como uma boa alternativa para incrementação de palhada ao solo e pecuária de corte. No teor de proteína, o tratamento Milho+ P. Maximum cv. Aruana se destaca, sendo ótimo para a pecuária leiteira, de grande destaque na região Sudoeste do Paraná. / Crop-animal System is a system with emphasis on the recovery of degraded areas and aims to maximize the use of land to produce greater quantities of biomass. It allows the cultivation of different plant species in the same area, time and / or space. The combination of corn and forage is important in this system. It ensures to the producer diversity in the income and guarantee the system's sustainability. In this context, the aim of this work is to evaluate an alternative combination of corn and forage in the southwest of Paraná, in a subtropical climate.The plantation of crop with Brachiaria Ruziziensis, Brachiaria Brizantha cv. Piatã,and Panicum Macimum cv. Aruana, was at the beginning of October 2014. The experiment was arranged in four repetitions. We evaluated the production of dry matter (DM) of maize silage point, total biomass, the forage yield components for corn productivity and nitrogen in the tissue of both species. Productivity of corn silage there was no significant difference between the treatments, but, Corn + B. Ruziziensis in the grain yield it was the treatment with lower production, with only 5486.88 kg ha-1. In the production of corn silage + forage, treatment Corn + B. Ruziziensis showed higher DM production, 21,502.5 kg ha-1, followed by treatment Corn + B. Brizantha cv. Piatã with 21,192.6 kg ha-1 DM, and treatment Corn + P. Maximum cv. Aruana with lower production. It was observed that the higher the forage biomass productivity, the smaller the grain yield in forage consortium treatments. There is a greater efficiency in the production of silage when there is a greater increase in forage. In the three forage cutting times, Corn + B. Ruziziensis treatment obtained higher biomass yield. In the case of nitrogen competition, the results were not significant for both treatments compared with single corn, there was no competition from forage with the corn crop by nutrient. The P. Maximum cv. Aruana got a lower rate in the production of biomass, but the question crude protein was the highest percentages estimated 165.6 g kg-1, leading the producer to have good alternatives as their primary goal. In the case of biomass, the Corn+ B.Ruziziensis treatment would be a good alternative to incrementing straw to the soil and also for beef cattle activity. On protein, Corn fits+ P. Maximum cv. Aruana, it’s great for dairy farming that has great prominence in the Paraná Southwest region.

No description available.

A agrofloresta visa diminuir os efeitos ocasionados pela interferência humana no ambiente auxiliando a conservação da biodiversidade. Neste trabalho o objetivo foi verificar os indicadores químicos, físicos e biológicos do solo de uma agrofloresta em desenvolvimento inicial. O estudo foi realizado na unidade didática/demonstrativa de agrofloresta, localizada na Universidade Tecnológica Federal do Paraná (UTFPR), Câmpus Dois Vizinhos. Foram coletadas amostras de solo e instaladas armadilhas para amostragem da fauna epiedáfica em seis áreas (tratamentos), sendo: quatro quadrantes da agrofloresta, uma área de mata secundária e uma área em sistema de integração lavoura-pecuária. As coletas foram realizadas em 2013 e em 2015, ambas no mês de novembro, em seis pontos de coleta (pseudoreptições), estratificadas em três profundidades: 0-5, 5-10 e 10-20 cm. As análises químicas de solo realizadas foram de teor de macronutrientes, alumínio e matéria orgânica e calculados índices relacionados. As análises físicas realizadas foram de densidade, macroporosidade e microporosidade. Também foi realizada avaliação da resistência do solo à penetração com uso de penetrômetro. A fauna epiedáfica foi coletada com armadilhas Pitfall-traps. Para avaliação da atividade microbiana do solo foi determinada a mineralização do C-CO2 na camada de 0-5 cm. Os dados foram submetidos à Análise de Variância, seguida de comparação de médias dos tratamentos pelo teste de Scott-Knott. Para verificar se existia diferenças entre os anos de coleta (2013 e 2015) foi aplicado o teste pareado de Wilcoxon ou o teste t pareado. Os indicadores de qualidade física do solo da agrofloresta estão em níveis intermediários, semelhantes em sua maioria ao sistema de integração lavoura pecuária, mas ainda abaixo dos indicadores de uma mata nativa secundária. Foi possível verificar que comparando as avaliações de 2013 com as de 2015, não houve diferença significativa para grande parte das variáveis analisadas. A avaliação da melhoria do solo de uma agrofloresta com pouco tempo de implantação, pode ser realizada utilizando os atributos físicos e biológicos do solo. / Agroforestry aims to reduce the effects caused by human interference in the environment, helping to conserve biodiversity. In this work the objective was to verify the chemical, physical and biological indicators of the soil of an agroforest in initial development. The study was carried out in the didactic / demonstration unit of agroforestry, located at the Universidade Tecnológica Federal do Paraná (UTFPR), Câmpus Dois Vizinhos. Soil samples were collected and traps were installed to sample the epiedaphic fauna in six areas (treatments): four agroforestry quadrants, the secondary forest area and an area under crop-livestock integration system. The collections were carried out in 2013 and 2015, both in November, at six collection points (pseudoreptions), stratified into three depths: 0-5, 5-10 and 10-20 cm. The soil chemical analyzes were of macronutrients, aluminum and organic matter, and related indexes were calculated. The physical analyzes were of density, macroporosity and microporosity. It was also evaluated soil penetration resistance using penetrometer. Epidaphic fauna was collected with Pitfall-traps traps. To evaluate the microbial activity of the soil, the C-CO2 mineralization was determined in the 0-5 cm layer. The data were submitted to Analysis of Variance, followed by comparison of means of treatments by the Scott-Knott test. To verify if there were differences between the collection years (2013 and 2015) the Wilcoxon paired test or paired t-test was applied. The indicators of soil physical quality of agroforestry are at intermediate levels, similar to the integration system for livestock farming, but still below the indicators of a secondary native forest. It was possible to verify that comparing the evaluations of 2013 with those of 2015, there was no significant difference for most of the analyzed variables. The evaluation of the improvement of the soil of an agroforest with little time of implantation, can be realized using the physical and biological attributes of the soil.

A agrofloresta visa diminuir os efeitos ocasionados pela interferência humana no ambiente auxiliando a conservação da biodiversidade. Neste trabalho o objetivo foi verificar os indicadores químicos, físicos e biológicos do solo de uma agrofloresta em desenvolvimento inicial. O estudo foi realizado na unidade didática/demonstrativa de agrofloresta, localizada na Universidade Tecnológica Federal do Paraná (UTFPR), Câmpus Dois Vizinhos. Foram coletadas amostras de solo e instaladas armadilhas para amostragem da fauna epiedáfica em seis áreas (tratamentos), sendo: quatro quadrantes da agrofloresta, uma área de mata secundária e uma área em sistema de integração lavoura-pecuária. As coletas foram realizadas em 2013 e em 2015, ambas no mês de novembro, em seis pontos de coleta (pseudoreptições), estratificadas em três profundidades: 0-5, 5-10 e 10-20 cm. As análises químicas de solo realizadas foram de teor de macronutrientes, alumínio e matéria orgânica e calculados índices relacionados. As análises físicas realizadas foram de densidade, macroporosidade e microporosidade. Também foi realizada avaliação da resistência do solo à penetração com uso de penetrômetro. A fauna epiedáfica foi coletada com armadilhas Pitfall-traps. Para avaliação da atividade microbiana do solo foi determinada a mineralização do C-CO2 na camada de 0-5 cm. Os dados foram submetidos à Análise de Variância, seguida de comparação de médias dos tratamentos pelo teste de Scott-Knott. Para verificar se existia diferenças entre os anos de coleta (2013 e 2015) foi aplicado o teste pareado de Wilcoxon ou o teste t pareado. Os indicadores de qualidade física do solo da agrofloresta estão em níveis intermediários, semelhantes em sua maioria ao sistema de integração lavoura pecuária, mas ainda abaixo dos indicadores de uma mata nativa secundária. Foi possível verificar que comparando as avaliações de 2013 com as de 2015, não houve diferença significativa para grande parte das variáveis analisadas. A avaliação da melhoria do solo de uma agrofloresta com pouco tempo de implantação, pode ser realizada utilizando os atributos físicos e biológicos do solo. / Agroforestry aims to reduce the effects caused by human interference in the environment, helping to conserve biodiversity. In this work the objective was to verify the chemical, physical and biological indicators of the soil of an agroforest in initial development. The study was carried out in the didactic / demonstration unit of agroforestry, located at the Universidade Tecnológica Federal do Paraná (UTFPR), Câmpus Dois Vizinhos. Soil samples were collected and traps were installed to sample the epiedaphic fauna in six areas (treatments): four agroforestry quadrants, the secondary forest area and an area under crop-livestock integration system. The collections were carried out in 2013 and 2015, both in November, at six collection points (pseudoreptions), stratified into three depths: 0-5, 5-10 and 10-20 cm. The soil chemical analyzes were of macronutrients, aluminum and organic matter, and related indexes were calculated. The physical analyzes were of density, macroporosity and microporosity. It was also evaluated soil penetration resistance using penetrometer. Epidaphic fauna was collected with Pitfall-traps traps. To evaluate the microbial activity of the soil, the C-CO2 mineralization was determined in the 0-5 cm layer. The data were submitted to Analysis of Variance, followed by comparison of means of treatments by the Scott-Knott test. To verify if there were differences between the collection years (2013 and 2015) the Wilcoxon paired test or paired t-test was applied. The indicators of soil physical quality of agroforestry are at intermediate levels, similar to the integration system for livestock farming, but still below the indicators of a secondary native forest. It was possible to verify that comparing the evaluations of 2013 with those of 2015, there was no significant difference for most of the analyzed variables. The evaluation of the improvement of the soil of an agroforest with little time of implantation, can be realized using the physical and biological attributes of the soil.

Thesis (MSc. Agriculture (Agronomy)) -- University of Limpopo, 2019 / The traditional practice of farmers in Limpopo Province is to mixed and broadcast crops at planting without definite row arrangement. This practice hinders farm input application and results in low crop yields. Strip intercropping, where crops are planted with definite row arrangement, has the advantage of reducing inter-species competition, optimise plant population and increasing crop yield. This study aimed at improving cowpea-maize cropping systems using strip intercropping. The experiment was conducted at University of Limpopo farm and Ga-Thaba village. Five cowpea varieties (Glenda (check)), IT86K-499-35, IT82E-16, IT86D -1010, TVu-13464 and maize (PAN 6479) were evaluated using randomised complete block design with three replications. Data collected were days to flowering, days to maturity, plant height, canopy width, peduncle length, pod length, number of pods/plant, 100 seed weight, grain yield, fodder weight and land equivalent ratio was also determined. Data were analysed using the Statistix 9.0. The results revealed that in both locations TVu 13464 flowered early (50 days) respectively. At University of Limpopo farm TVu 13464, IT82E-16 and IT86D-1010 matured early (89, 88 and 91 days). At University of Limpopo farm, IT82E-16 had high cowpea grain yield (2230 kg/ha) under monocropping and also produced high grain yield of 1373 kg/ha during 2016/17 season. At Ga-Thaba, IT86D-1010 produced high cowpea grain yield of 1085 kg/ha under monocropping and during 2015/16 (660 kg/ha) while IT86K-499-35 also produced high grain yield of 915 kg/ha during 2016/17. The varieties showed yield stability depending on different locations. At University of Limpopo farm, strip intercropping achieved high maize grain yield of 3961 kg/ha during 2016/17. At Ga-Thaba, strip intercropping produced high maize grain yield 747 and 1024 kg/ha during 2015/16 and 2016/17, respectively. Monocropping produced low maize grain yield during 2015/16 with a mean of 425 kg/ha and mixed intercropping had mean of 499 kg/ha during 2016/17. The calculated LER for two crops over two seasons under strip intercropping ranged from 1.25 and 2.14, whereas under mixed intercropping, it ranged between 0.73 and 1.05 over two seasons at University of Limpopo farm. TVu 13464, IT82E-16 and IT86D-1010 are promising varieties for strip intercropping in low rainfall areas because of their early maturity and high grain yield. The calculated LER for two crops over two seasons xx under strip intercropping ranged from 1.62 and 2.98, whereas under mixed intercropping, it ranged between 0.76 and 1.67 in both seasons at Ga-Thaba. / National Research Foundation (NRF) and Water Research Commission (WRC)

Vineyard management strategies, including vineyard floor management and crop level management, can be used to influence vine vigor and fruit composition. Two studies were conducted to evaluate the impact of these practices on Pinot Noir in Oregon's Willamette Valley. Managing crop levels is common in cool climate vineyard production though it is a costly practice. With economic pressures, the premium winegrape industry is questioning whether they can reduce production costs and increase yields without compromising quality. A crop thinning trial was conducted in 2010 and 2011 to address these concerns and to better understand the role of vine balance on fruit composition. Crop levels were moderately (35% crop removed) or severely (65% crop removed) thinned at pre-bloom, fruit set, lag phase, or véraison and compared to full crop treatments. In both years, crop thinning reduced yields but had no effect on berry weight or cluster size. In 2010, poor fruit set reduced overall yields, and thinning treatments resulted in very few differences in vine growth, cluster architecture or fruit composition, including total soluble solids (TSS), pH, titratable acidity (TA), yeast assimilable nitrogen (YAN), anthocyanins, phenolics and tannins. In 2011, yields were much higher due to high fruit set and larger cluster size. No differences were found in vine growth (leaf areas or pruning weights) or fruit YAN, but thinned vines had higher TSS and pH and lower TA than full crop vines at harvest. Fruit thinned at lag phase and véraison had higher TSS and lower TA than fruit thinned pre-bloom. Intensity of thinning had a stronger influence on anthocyanin and tannin concentration than timing, while phenolics were not impacted by either factor. Ravaz index values (fruit yield/pruning weight) below 2.25 and leaf area to yield ratios of 2.25 to 3.25 m²/kg improved fruit composition in 2011 as did later season thinning, though data from the remaining years of this study will provide more insight into appropriate crop load metrics for cool climate Pinot Noir. A second study was implemented in 2011 to determine the impact of crop thinning in vines with different levels of vegetative vigor caused by three vineyard floor management techniques: permanent grass (Festuca rubra spp. rubra) cover (grass), alternating grass cover and tillage (grass & tilled), and tillage of every alleyway (tilled). Crop was thinned at the BB stage of berry development (EL stage 73) to one cluster per shoot (half crop) or not thinned (full crop); all cluster wings were removed at the time of thinning. Tillage treatments had been in place four years prior to the start of the study and competition for nitrogen in grass caused reduced early season vine growth, leaf chlorophyll and canopy size at both bloom and véraison while crop thinning increased canopy size at véraison. Yields were altered by tillage and crop thinning treatments, as grass had fewer clusters per shoot and berries per cluster, and crop thinning reduced yields to 64.7% of full crop across all tillage treatments. At harvest, grass had the lowest TA while TSS and pH were not affected by tillage. Crop thinning increased TSS but did not impact pH or TA. Anthocyanins were affected by both tillage and thinning and were found to be related to vine yield, YAN, leaf N, and leaf area index. Tannins were highest in grass but were not affected by crop thinning, and phenolics were not changed by either factor. Few interactions between tillage and crop thinning were found, but as variables such as yield per vine were impacted by both treatment factors, monitoring long term effects of crop / Graduation date: 2012

Les cultures de Brassicacées sont très courantes en agriculture urbaine à Montréal. Elles comportent cependant leur lot de problèmes liés aux insectes ravageurs, tels que la piéride du chou, Pieris rapae. L’utilisation de méthodes de lutte classique contre les insectes ravageurs, tels les insecticides, engendrent de sérieux dommages environnementaux, incluant la contamination de l’eau et du sol ainsi que la toxicité pour les plantes environnantes, les insectes auxiliaires et les microorganismes du sol. Le compagnonnage végétal, une pratique agroécologique alternative, est connue en tant que stratégie d’IPM (lutte intégrée contre les insectes ravageurs). L'objectif général de l'étude était d'évaluer in situ l'importance de diverses méthodes de compagnonnage sur l'infestation de P. rapae au sein du chou chinois, Brassica rapa. Les plantes utilisées dans les systèmes de compagnonnage étaient des cultures-pièges (Eruca sativa et Brassica carinata), des plantes compagnes principales qui étaient des plantes insectaires et répulsives pour les insectes ravageurs (Tagetes erecta, Amaranthus cruentus et Ocimum grattissimum) ainsi que des plantes compagnes secondaires (Solanum aethiopicum, Ocimum basilicum et Hibiscus sabdariffa). Les paramètres de physiologie végétale ainsi que les structures des communautés microbiennes et d’insectes ont été suivis de près tout au long de la saison croissance où l’expérience a eu lieu. La taille des larves était significativement plus importante au sein de la monoculture (contrôle) et les taux de concentration de glucosinolates dans les feuilles de Brassica rapa étaient deux fois plus élevés dans les contrôles comparativement aux systèmes de cultures plus diversifiés. Une PERMANOVA a confirmé une différence significative entre les méthodes de cultures concernant la composition des communautés d’insectes bénéfiques. Les communautés bactériennes du sol ont été améliorées par l'agriculture durable par rapport au sol d'origine et ont été bonifiées dans les systèmes de compagnonnage végétal (plus diversifiés). L'étude a mis en évidence les avantages de l'agroécologie, y compris le compagnonnage végétal, en termes de lutte intégrée contre les insectes ravageurs et d'autres composantes de l'agroécosystème. / Brassica crops are very common culture for urban farmers in Montreal where insect pests like the cabbage whitefly, Pieris rapae, are a real concern. The use of conventional insect pest control methods, such as insecticides, causes serious damages to a highly anthropized and therefore already constrained environment. These include air, water and soil contamination, as well as toxicity to surrounding beneficial insects, soil microorganisms, plants and the entire food chain. Companion planting, an agroecological practice, is an alternative strategy for insect pest management. The general objective of the study was to evaluate in situ the relevance of various traditional methods of companion planting on infestation of Chinese cabbage, Brassica rapa, by P. rapae. The plants used in the companion systems were two trap crop species: Eruca sativa and Brassica carinata; Tagetes erecta, Amaranthus cruentus and Ocimum grattissimum were used like companion plants because of their properties as insectary plants and repellent species against the targeted pest; Solanum aethiopicum, Ocimum basilicum and Hibiscus sabdariffa were also considered (secondary) companion plant species. Plant physiological parameters as well as microbial and insect community structure were carefully monitored over the growing season where this experiment took place. Larval size was significantly greater in the monoculture and glucosinolate concentrations in leaves of Brassica rapa was two-times higher in control than in more diversified cultivation systems. With larger yield and the absence of pest in the field, ‘trap cropping system’ was overall the most efficient albeit the 'mix of companion planting’ system had the lowest leaf area damage. A PERMANOVA confirmed a significant difference between the cultivation methods regarding beneficial insect communities’ composition. Belowground, soil bacterial communities were readily modified by sustainable agriculture practice, even more so in biodiversified systems. The study highlighted benefits of agroecology, including companion planting, in terms of integrated pest management and other components of the agroecosystem.