Submitted by (edna.saturno@ufrpe.br) on 2016-11-28T15:50:21Z No. of bitstreams: 1 Nivea Maria da Silva Gusmao.pdf: 595496 bytes, checksum: 545bce88a2420d3d15abedededfabe8f (MD5) / Made available in DSpace on 2016-11-28T15:50:21Z (GMT). No. of bitstreams: 1 Nivea Maria da Silva Gusmao.pdf: 595496 bytes, checksum: 545bce88a2420d3d15abedededfabe8f (MD5) Previous issue date: 2012-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Among the pests that attack stored beans Vigna unguiculata (L.) Walp. stands out the cowpea weevil Callosobruchus maculatus (Fabr., 1775), responsible for qualitative and quantitative losses. The use of synthetic fumigants and protectors are widely used on its control, however alternative products such as powders and essential oils of plant origin, have been extensively investigated in recent years, with promising results. Thus, this study aimed to: (a) perform the chromatographic analysis and mass spectrometry in Eucalyptus. citriodora Hook., Eucalyptus. staigeriana F., essential oils; (b) evaluate the toxicity by contact and fumigation; (c) test the repellent effect. The major component of E. staigeriana essential oil was limonene (28.73%) and geranial (15.20%), and for E. citriodora essential oil was Citronelal (89.59%) and Citronelil acetate (3.34). The LC50s of F. vulgare, E. citriodora, E. staigeriana and C. winterianus oils in contact tests were estimated in 4.19, 7.09, 7.44, 7.93μL/20g of bean, respectively. According to regression analysis, the higher the mortality rate, lower was the number of eggs laid and emerged insects. In fumigation tests for adults, the LC50s ranged from 2.58 to 7.85 μL/L of air and the toxicity reasons from 1.25 to 3.04. In all concentrations tested, E. citriodora and C. winterianus oils were repellent to C. maculatus adults. F. vulgare was classified as neutral, while E. staigeriana was neutral at low concentrations and repellent only at the highest concentration 12μL/20g of cowpea. The percentages of reduction of posture caused by the oils esssenciais ranged from 3.26 to 100% and adult emergence from 0.46 to 100%, especially C. winterianus that the highest concentration (15μl/20g), reduced by 100% these parameter. / Dentre as pragas que atacam o feijão Vigna unguiculata (L.) Walp. armazenado destaca-se o caruncho Callosobruchus maculatus (Fabr., 1775), responsável por perdas qualitativas e quantitativas. Os inseticidas sintéticos fumigantes e protetores são muito utilizados no seu controle, porém produtos alternativos como pós e óleos essenciais de origem vegetal, têm sido bastante pesquisados nos últimos anos, com resultados promissores. Assim, o presente trabalho teve como objetivos: (a) efetuar a análise cromatográfica e de espectrometria de massas nos óleos essenciais de Eucalyptus citriodora Hook e Eucalyptus. staigeriana F.; (b) avaliar a toxicidade por contato e fumigação; (c) testar o efeito repelente. Os compostos majoritários do óleo de E. staigeriana foram o Limoneno (28,73%) e Geranial (15,20%), e para E. citriodora foi Citronelal (89,59%) e Citronelil acetate (3,34%). As CL50s dos óleos de F. vulgare, E. citriodora, E. staigeriana e C. winterianus, nos testes de contato, foram estimadas em 4,19; 7,09; 7,44; 7,93μL/20g de feijão, respectivamente. De acordo com as análises de regressão, quanto maior a mortalidade, menor foi o número de ovos depositados e de insetos emergidos. Nos testes de fumigação para adultos, as CL50s variaram entre 2,58 a 7,85 μL/L de ar e as razões de toxicidade de 1,25 a 3,04. Em todas as concentrações testadas, os óleos de E. citriodora e de C. winterianus foram repelentes para adultos de C. maculatus. F. vulgare foi classificado como neutro, enquanto E. staigeriana foi neutro nas concentrações menores e repelente apenas na maior concentração de 12μL/20g de feijão. As percentagens de redução da postura provocadas pelos óleos esssenciais, variaram de 3,26 a 100% e da emergência de adultos de 0,46 a 100%, destacando-se C. winterianus, que na maior concentração (15μl/20g), reduziu em 100% estes parâmetros.

Submitted by (edna.saturno@ufrpe.br) on 2016-12-02T12:15:37Z No. of bitstreams: 1 Rodrigo Lenadro Braga Coitinho.pdf: 431687 bytes, checksum: 3510e17dbd6224b39b136428e9bf81c4 (MD5) / Made available in DSpace on 2016-12-02T12:15:37Z (GMT). No. of bitstreams: 1 Rodrigo Lenadro Braga Coitinho.pdf: 431687 bytes, checksum: 3510e17dbd6224b39b136428e9bf81c4 (MD5) Previous issue date: 2009-02-02 / The essential oils are promising alternative for the management of Sitophilus zeamais in stored maize. In this investigation, toxicity, repellency and persistence of essential oils in stored maize were evaluated using S. zeamais. The oil’s LC50s from leaves of Piper hispidinervum, Eugenia uniflora, Cinnamomum zeylanicum, eugenol compound, Piper marginatum, Schinus terebinthifolius and Melaleuca leucadendron and green fruits of S terebinthifolius, in the tests of contact and ingestion were estimated at 1.0; 11.6; 14.2; 14.8; 21.1; 57.7, 75.8 and 98.8 μL/40g maize, respectively. In fumigation tests for adults, the LC50s ranged from 94.7 to 0.53 μL/L of air and the toxicity ratios ranged from 178.7 to 2.0. In the fumigation for larvae with 7 to 14 days of age, only eugenol did not differ from control concerning number of adults emerged. In larvae with 7 to 21 days, the oils of green fruits from S. terebinthifolius and P. hispidinervum showed the best performance in relation to the control. Percentages of repellency varied between 97.4 (P. marginatum and C. zeylanicum) to 81% (P. hispidinervum). In the initial storage period (after impregnation), mortality of S. zeamais ranged between 93.8 (P. hispidinervum, Melaleucaleucadendron and eugenol) to 100% (E. uniflora, green fruits of S. terebinthifolius and P. marginatum). From 30 days, mortality generally decreased, except for P. marginatum (92.2%). According to the regression equations adjusted for the number of S. zeamais emerged throughoutthe storage period, there was no statistical significance for the oils of S. terebinthifolius and P. marginatum and control. For the average, the oil from P. marginatum was the most persistent, providing emergency of only 0.30 insects differing from the other oils and the control. / Os óleos essenciais constituem alternativa promissora para o manejo de Sitophilus zeamais em milho armazenado. Neste trabalho avaliou-se a toxicidade, a repelência e a persistência de óleos essenciais em milho armazenado, utilizando-se S. zeamais. As CL50s dos óleos de folhas de Piper hispidinervum, Eugenia uniflora, Cinnamomum zeylanicum, composto eugenol, Piper marginatum, Schinus terebinthifolius, e Melaleuca leucadendron e de frutos verdes de S terebinthifolius, nos testes de contato e ingestão, foram estimadas em 1,0; 11,6; 14,2; 14,8; 21,1; 57,7; 75,8 e 98,8 μL/40g de milho, respectivamente. Nos testes de fumigação para adultos, as CL50s variaram entre 94,7 a 0,53 μL/L de ar e as razões de toxicidade estiveram entre 178,7 a 2,0. Na fumigação para larvas de 7 a 14 dias de idade, apenas o eugenol não diferiu da testemunha, quanto ao número de adultos emergidos. Em larvas com 7 a 21 dias, os óleos de frutos verdes de S. terebinthifolius e de P. hispidinervum apresentaram o melhor desempenho, em relação à testemunha. As percentagens de repelência variaram entre 97,4 (P. marginatum e C. zeylanicum) a 81% (P. hispidinervum). No período inicial de armazenamento (logo após a impregnação), asmortalidades de S. zeamais variaram entre 93,8 (P. hispidinervum, Melaleuca leucadendron e eugenol) a 100% (E. uniflora, frutos verdes de S. terebinthifolius e P. marginatum). A partir dos 30 dias, as mortalidades, de um modo geral, decresceram, com exceção de P. marginatum(92,2%). De acordo com as equações de regressão ajustadas para o número de S. zeamais emergidos em todo o período de armazenamento, não houve significância estatística para os óleos de S. terebinthifolius e de P. marginatum e testemunha. Em relação à média geral, o óleo de P. marginatum foi o mais persistente, proporcionando emergência de apenas 0,30 insetos, diferindo dos demais óleos e da testemunha.

Thesis (M.Sc. Agriculture (Agronomy) -- University of Limpopo, 2019 / Erratic rainfall and insect infestation are some of the factors that limit cowpea production in Limpopo (Asiwe, 2009). Improved cowpea varieties available for dryland production in Limpopo do not meet the farmer’s needs. Specific trait crosses are needed to be made with adapted varieties for the purpose of developing high yielding, pest tolerant and adapted varieties. Varieties with desired specific traits were planted in isolation plots for outcrossing by insects. F1 lines derived from parental lines that were half sib seeds were harvested and planted as F2, and seeds obtained from F2 generation were used to develop F3 segregating population at University of Limpopo Experiential Farm, Syferkuil, and planted along with parents. This F3 generation forms the current evaluation on which this report is based. Data collected included; aphid severity (measured on a 9-point scale), number of days to 90 % maturity, grain yield, 100 seed weight and number of genotypes selected for advancement. Results showed significant variation among progeny over parents therefore expressing transgressive segregation. Genotypes derived from pedigree TX08-30-5 were five while pedigree IT98K-205-8 and IT97K-499-35 had four genotypes each that expressed early maturity (80-90 days) which are desirable for evading drought. Twenty-three genotypes from pedigree GEC and three from pedigree IT97K-499-35 obtained grain yield (>101 g/plot and >161 g/plot) that was better than their parents. Only one genotype derived from pedigree TX08-30-1 expressed high resistance to aphids better than the parent with a mean aphid score range of 1-2. Four genotypes from pedigree TX08-30-5 obtained bigger 100 seed weight (>18.6 g) compared to parent. These progeny also proved to be high yielders as they expressed heterosis for all yield attributes than their parents. Eighty-two genotypes were selected for advancement. Significant variations were observed among progeny giving opportunity to make selections. In most cases, genotypes outperformed their parents which indicate positive heterosis. The 82 promising genotypes selected will be advanced for further selections from multi location testing for stability and adaptation.

No description available.

Tesis por compendio / [EN] The management of Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae), the worst threat for palm trees worldwide, consists in several preventive and curative techniques, but because of its low efficacy the insect still causes major economic and landscape losses. In order to define aspects that have facilitated its rapid dispersal and contribute to improving its management, the effects of vision and flight, which influence the mobility of R. ferrugineus, have been analysed. The chromatic preference of R. ferrugineus has been studied by analysing their captures in coloured bucket traps. Black traps capture the highest number of insects compared with the other colours studied, both when they contain olfactory attractants, as when these compounds are not used, demonstrating that colour by itself is a crucial attraction factor. Moreover, the spectral reflectance of studied colours and of some P. canariensis tissues has been analysed. The wavelength spectrum of black shows great similarity to that of fibres of P. canariensis, so this may be the reason why R. ferrugineus prefers this colour. Regarding sex ratio of the insect in traps, female captures are significantly greater in those baited with olfactory attractants. However, a higher number of female captures does not always occur when these compounds are not used. On the other hand, the study of sex ratio in natural populations of the insect demonstrates that the proportion is one female per male. Therefore, the greater number of captures of females in commercial traps is due exclusively to their greater attraction towards the olfactory attractants used. Another of the analysed aspects has been the flight potential of R. ferrugineus under laboratory conditions. In order to know more about the mobility of this insect, different parameters have been studied using a computer-monitored flight mill. The selected parameters used to define the R. ferrugineus flight potential have been the number of flights, total distance flown, longest single flight, flight duration, and average and maximum speed. Moreover, the influence of sex, body size, and age of the adults on the aforementioned parameters has been examined. R. ferrugineus sex does not have a significant effect on the compared flight parameters. The body size in females is significantly greater, but this does not influence their flight potential. A higher percentage of flight is observed for adults with an age range of 8-23 days old, compared to the 1-7 day old adults. However, age does not significantly influence their flight potential. By analysing the longest single flight undertaken by each adult, up to 63% of the insects can be classified as short-distance flyers (<500m), 27.3% as medium-distance flyers (500-5000m), and >9% as long-distance flyers (>5000m). Finally, the flight behaviour and dispersal of R. ferrugineus have been analysed under field conditions using the mark-release-recapture method. This test focused on detecting the influence of different factors, such as sex, temperature, relative humidity, and solar radiation, in the take-off and dispersal of the adult insects. Take-off probability of R. ferrugineus adults is significantly greater in males Moreover, this probability increases when temperature and solar radiation rise. Concerning the insect dispersal by flying, the number of recaptures is influenced by temperature, increasing significantly when this factor increases. Likewise, dispersal distances also increase significantly as temperatures rise. The insect tends to fly distances <500m (77.1% of recaptured adults), following the same tendency observed in studies performed using the flight mill. However, R. ferrugineus is able to travel up to 7km, being recorded under laboratory conditions a potential flight up to 20km. To conclude, dispersal time of the adults is very short (more than 90% of the adults were recaptured during the first 7 days), being significantly lower when relative humidity increases. / [ES] El manejo de Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae), una de las peores amenazas para las palmeras en el mundo, se lleva a cabo mediante la aplicación de diversas técnicas de prevención y control, pero debido a la baja eficacia de éstas la plaga continúa causando importantes pérdidas económicas y paisajísticas. Para definir los aspectos que han intervenido en su dispersión y contribuir a mejorar su manejo, se ha analizado el efecto de la visión y el vuelo en la movilidad de los adultos de R. ferrugineus. Se ha estudiado la preferencia cromática mediante el análisis de sus capturas en trampas cubo coloreadas. Las trampas negras capturan el mayor nº de insectos en comparación con el resto de colores estudiados, tanto cuando contienen atrayentes olfativos como cuando no los contienen, demostrando que el color por sí mismo es un factor importante de atracción. Además, se ha analizado el espectro de longitud de onda de los colores estudiados y de diversos tejidos de P. canariensis. El espectro del color negro muestra gran similitud con el de las fibras de P. canariensis, es por esto por lo que R. ferrugineus podría presentar esta preferencia. En relación a la proporción de sexos en trampas que contienen atrayentes olfativos, las capturas de hembras son significativamente más elevadas. En cambio, sin éstos no siempre se produce un mayor nº de capturas de este sexo. Por otro lado, el estudio de la proporción de sexos en poblaciones naturales muestra una ratio de una hembra por macho. Por tanto, las mayores capturas de hembras en trampas se deben a una mayor atracción de éstas hacia los atrayentes olfativos. Otro aspecto estudiado ha sido el potencial de vuelo de R. ferrugineus bajo condiciones de laboratorio. Con la finalidad de conocer la movilidad de este insecto se han analizado diversos parámetros mediante la utilización de un molinillo de vuelo computerizado. Los parámetros estudiados han sido: nº vuelos, distancia total volada, vuelo más largo, duración del vuelo y velocidades media y máxima. Además, se ha analizado como influye el sexo, el tamaño del cuerpo y la edad de los adultos en dichos parámetros de vuelo. El sexo de R. ferrugineus no muestra un efecto significativo sobre los parámetros de vuelo comparados. El tamaño del cuerpo de las hembras es significativamente mayor, pero no influye estadísticamente en su potencial de vuelo. En adultos con edades de entre 8-23 días se observa un mayor porcentaje de vuelo que en aquellos con 1-7 días de edad. En cambio, la edad no influye significativamente sobre su potencial de vuelo. Al analizar el vuelo más largo, obtenemos que >63% de los insectos se clasifican como voladores de corta distancia (<500m), el 27.3% de media distancia (500-5000m), y >9% de larga distancia (>5000m). Finalmente, se ha analizado en campo el comportamiento de vuelo y dispersión de R. ferrugineus mediante la técnica de marcaje-suelta-recaptura. Este ensayo ha permitido estudiar la influencia del sexo, la temperatura (Tª), la humedad relativa y la radiación solar, en el despegue y dispersión de los adultos. La probabilidad de despegue de R. ferrugineus es significativamente mayor en machos. Además, esta probabilidad se incrementa cuando la Tª y la radiación solar aumentan. Respecto a la dispersión del insecto mediante el vuelo, el nº de recapturas se ve influenciado por la Tª, aumentando significativamente cuando ésta se incrementa. De la misma manera, las distancias de dispersión también se incrementan significativamente a media que lo hace la Tª. El insecto tiende a volar distancias <500m (77.1% de los adultos recapturados), siguiendo la misma tendencia observada en laboratorio. No obstante, R. ferrugineus es capaz de recorrer hasta 7km, llegando a registrarse vuelos potenciales en laboratorio de hasta 20km. Por último, el tiempo de dispersión de los adultos es muy corto (>90% se recapturaron en los 7 primeros días), reduciéndose / [CA] El maneig de Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae), una de les pitjors amenaces per a les palmeres en tot el món, es porta a terme mitjançant l'aplicació de diverses tècniques de prevenció i control, però degut a la baixa eficàcia d'aquestes l'insecte continua causant importants pèrdues econòmiques i paisatgístiques. Per a definir els aspectes que han intervingut en la seua dispersió i contribuir a la millora del seu maneig, s'ha analitzat l'efecte que tenen la visió i el vol en la mobilitat dels adults de R. ferrugineus. S'ha estudiat la preferència cromàtica mitjançant l'anàlisi de les seues captures en trampes poal acolorides. Les trampes negres capturen el major nombre d'insectes en comparació amb la resta de colors estudiats, tant quan contenen atraients olfactius com quan no els contenen, demostrant que el color per ell mateix és un factor important d'atracció. A més, s'ha analitzat l'espectre de longitud d'ona dels colors estudiats i de diversos teixits de P. canariensis. L'espectre del color negre mostra gran similitud amb el de les fibres de P. canariensis, és per açò pel que R. ferrugineus podria presentar aquesta preferència. En relació a la proporció de sexes a les trampes que contenen atraients olfactius, les captures de femelles són significativament més elevades. En canvi, sense aquests no sempre es produeix un major nombre de captures d'aquest sexe. Per altra banda, l'estudi de la proporció de sexes en poblacions naturals demostra que la ràtio és d'una femella per mascle. Per tant, les majors captures de femelles en trampes es deuen a una major atracció d'aquestes cap als atraients olfactius utilitzats. Altre aspecte estudiat ha sigut el potencial de vol de R. ferrugineus sota condicions de laboratori. Amb la finalitat de conèixer la mobilitat d'aquest insecte s'han analitzat diversos paràmetres mitjançant la utilització d'un molinet de vol computeritzat. Els paràmetres estudiats han sigut: nombre de vols, distància total volada, vol més llarg, duració del vol i velocitats mitjana i màxima dels vols. A més, s'ha analitzat com influeixen el sexe, el tamany del cos i l'edat dels adults en dits paràmetres de vol. El sexe de R. ferrugineus no mostra un efecte significatiu sobre els paràmetres de vol comparats. El tamany del cos de les femelles és significativament major, però no influeix estadísticament en el seu potencial de vol. En adults amb edats d'entre 8-23 dies s'observa un major percentatge de vol que en aquells amb 1-7 dies d'edat. En canvi, l'edat no influeix significativament sobre el seu potencial de vol. En analitzar el vol més llarg, obtenim que més del 63% dels insectes es classifiquen com voladors de curta distància (<500m), el 27.3% de mitja distància (500-5000m), i >9% de llarga distància (>5000m). Finalment, s'ha analitzat en camp el comportament de vol i dispersió de R. ferrugineus mitjançant la tècnica de marcatge-solta-recaptura. Aquest assaig ha permès estudiar la influència del sexe, la temperatura, la humitat relativa i la radiació solar, en l'enlairament i dispersió dels adults. La probabilitat d'enlairament de R. ferrugineus és significativament major en mascles A més, aquesta probabilitat s'incrementa quan la temperatura i la radiació solar augmenten. Respecte a la dispersió de l'insecte mitjançant el vol, el nombre de recaptures es veu influenciat per la temperatura, augmentant significativament quan aquesta s'incrementa. De la mateixa manera, les distàncies de dispersió també s'incrementen significativament a mesura que ho fa la temperatura. L'insecte tendeix a volar distàncies <500m (77.1% dels adults recapturats), seguint la mateixa tendència observada en laboratori. No obstant, R. ferrugineus és capaç de recórrer fins a 7km, arribant-se a registrar vols potencials en laboratori de fins a 20km. Per últim, el temps de dispersió dels adults és molt curt (>90% es recapturaren en els 7 primers die / Ávalos Masó, JA. (2015). Factors influencing the mobility of Red Palm Weevil Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) adults [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59394 / Compendio

Vid föryngring ger markberedning en bra förutsättning för plantan att överleva och växa, och med mindre risk för snytbaggeangrepp. Syftet med denna studie var att undersöka hur snytbaggeskydd och olika markberedningsmetoder långsiktigt påverkar stamantal, medelhöjd och volymproduktion hos gran (Picea abies). Markberedningsmetoderna som jämfördes var högläggning, fläckmarkberedning och inversmarkberedning. De jämfördes med att inte markbereda alls. Hälften av plantorna var behandlade mot snytbagge med permetrin, dessa var jämt fördelade i försöket. Studien genomfördes i en försöksyta 9284, vid SLU:s försökspark i Siljansfors, Mora kommun. Beståndet var 17 år när det mättes (16 år efter plantering) hösten 2018. Då mättes trädens höjd, diameter samt grönkronans höjd. Volym beräknades med volymfunktioner. Högläggning, inversmarkberedning, och fläckmarkberedning (i nu nämnd ordning) och snytbaggeskydd gynnade granplantornas volymtillväxt, gav flest stammar samt högst höjd. Att högläggning och inversmarkberedning var så framgångsrika i detta försök beror troligen på att marken i Siljansfors är näringsfattig och fuktig. Hög planteringspunkt ökar risken för en planta att torka. Permetrinbehandling hade en positiv effekt på volymen och stamantalet, dock var det ingen signifikant skillnad vad gäller höjden. Markberedning samt permetrinbehandling ger bestående långsiktiga resultat för produktionen. / In regenerations, soil preparation provides good conditions for plants to survive and grow, and reduces the risk of damage by pine weevil (Hylobius abietis). The aim of this study was to investigate the long-term effect of protection against pine weevil damage and the long-term effect of different soil scarification methods on the number of trees, tree height and the volume production of spruce (Picea abies). The soil preparation methods that were compared were mounding, patch scarification and the inverse method. These were compared as well as to, no soil preparation at all. Half of the plants were treated against pine weevil with permethrin. These were evenly distributed in the experiment. The study was conducted in the trial area 9284, at SLU's experimental park in Siljansfors, Mora municipality. The trees were 17 years old when measured (16 years after planting) in the autumn 2018. Then tree height, diameter and the height of the green crown was measured. Volume was calculated with volume functions. Mounding, the inverse method and patch scarification (in the order mentioned) and pine weevil protection benefited the volume production of the spruce trees, the numbers of trees and tree height. The fact that mounding and the inverse method was so successful in this experiment is probably due to that the soil in Siljansfors is nutrient-poor and moist. High planting points increases the risk of drought. Permethrin treatment had a positive effect on volume production and the number of plants, however, there was no significant difference regarding tree height. Soil preparation and permethrin treatment provide lasting long-term effects on production.

Some aspects of the presence of systemic endophytic fungi in agriculturally important New Zealand grasses were studied in relation to plant breeding. Seedling resistance to adult Argentine stem weevil feeding in perennial ryegrass, Italian ryegrass and tall fescue was found to be related to the presence of their respective Acremonium endophytes in the seed rather than to plant genetic resistance. In addition a study of perennial ryegrass revealed that this resistance was independent of endophyte viability. The seedling resistance conferred by the endophyte of Italian ryegrass was found to be beneficial for field establishment. This endophyte differs from that in perennial ryegrass and tall fescue in that it does not confer resistance to Argentine stem weevil on mature plants, but only on seedlings. The extent of plant genetic seedling tolerance to adult Argentine stem weevil feeding was limited to broad inter-specific differences, with tall fescue more tolerant than perennial ryegrass and both of these more tolerant than Italian ryegrass. This ranking corresponds with previous observations on feeding preference on mature plants. A study of factors affecting the concentration of endophyte mycelia in infected seed of perennial ryegrass revealed that plant genetic factors had little effect. The major factors studied were: 1) the endophyte concentration in the maternal parent plant directly influenced the endophyte concentration in the seed. 2) nitrogen fertilizer applications to a seed crop reduced the concentration of mycelia in the seed, with earlier applications having a greater effect. 3) application of the fungicide propiconazole (Tilt) to a seed crop reduced the endophyte concentration in the seed. 4) the endophyte concentration in the seed was found to directly influence the endophyte concentration in seedlings, six month old plants and that of seed harvested from a first year seed crop. As there have been no previous reports of tetraploid perennial ryegrass cultivars with endophyte an experiment was conducted to determine if these could be developed by the standard procedure of colchicine treatment. The results revealed that endophyte was retained following colchicine treatment.

Dry bean (Phaseolus vulgaris L.) is economically and nutritionally an important legume, not only in Malawi, but in many parts of Africa and Latin America. Unfortunately, two bruchid species (Acanthoscelides obtectus Say, and Zabrotes subfasciatus Boheman) are known to cause extensive damage in storage, reducing the economic importance, food value and planting value of the crop. The aim of this study was to: i) ascertain farmers’ perceptions of the importance of bruchids as storage pests, and to identify their preferred varietal traits in dry beans; ii) screen Malawian dry bean landraces for effective and adaptable sources of resistance to the two bruchid species; iii) determine the gene action and inheritance of bruchid resistance. Farmers’ perceptions on the importance of the two bruchid species to beans both in the field and in storage were established using a participatory rural appraisal (PRA) in three extension planning areas (EPAs) in Lilongwe agricultural development division (ADD). Results confirmed that the two bruchid species are important storage pests, causing serious storage losses among smallholder farmers. In the absence of any control measures, farmers indicated that more than 50% of their stored beans could be lost to bruchids. Indigenous bruchid control measures are not very effective, making it necessary to search for other control methods. It was also clear from the PRA results that breeders need to consider both agronomic and culinary traits in bean cultivar development. This would enhance uptake of newly developed varieties. To address the problem of bruchid damage experienced by smallholder farmers, a total of 135 dry bean genotypes, comprising 77 landraces and 58 improved varieties (obtained from collaborating partners) were tested under laboratory infestation (nochoice test methods) and field infestation (free-choice test methods). The objective of this study was to identify effective sources of resistance to the two bruchid species. Results of the study showed that there was a wide variation among the genotypes for resistance to the two bruchid species. Overall results showed that 88% of the genotypes ranged from susceptible to highly susceptible to Z. subfasciatus and only 12% of the genotypes were moderately resistant to resistant. Genotype screening for resistance to A. obtectus showed that only 12.5% were resistant, whereas 87.5% were moderately to highly susceptible. All of the improved genotypes were 100% susceptible to A. obtectus in storage. One landrace, KK35, consistently showed a high level of resistance to both bruchids under laboratory infestation, with results similar to the resistant checks (SMARC 2 and SMARC 4), while another landrace, KK90, displayed stable resistance under both laboratory and field infestation. However, performance of most genotypes was not consistent with field and laboratory screenings, suggesting that mechanisms of bruchid resistance in the field are different from that in the laboratory and field screening should always be used to validate laboratory screening. Resistance in the field was not influenced by morphological traits. The seed coat played a significant role in conferring resistance to both bruchid species in the laboratory, whereas arcelin did not play any significant role in conferring resistance in the landraces. The inheritance of resistance to A. obtectus was studied in a 6 x 6 complete diallel mating design, involving crosses of selected Malawian dry bean landraces. The F1 crosses, their reciprocals, and six parents were infested with seven F1 generation (1 to 3 d old) insects of A. obtectus in a laboratory, no-choice test. There were significant differences among genotypes for general combining ability (GCA) and specific combining ability (SCA). However, SCA accounted for 81% of the sum of squares for the crosses, indicating predominance of the non-additive gene action contributing to bruchid resistance. A chi-square test for a single gene model showed that 5 of the 13 F2 populations fitted the 1:2:1 segregation ratio of resistant, intermediate and susceptible classes, respectively indicating partial dominance. The eight F2 populations did not conform to the two gene model of 1:4:6:4:1 segregation ratio of resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible classes, respectively. Average degree of dominance was in the partial dominance range in five F3 populations, but in general resistance was controlled by over-dominance gene action in the F2 populations. The additive-dominance model was adequate to explain the variation among genotypes indicating that epistatic effects were not important in controlling the bruchid resistance. The frequency distribution of the 13 F3 populations for resistance to A. obtectus provided evidence for transgressive segregation, suggesting that resistance is conditioned by more than one gene. Reciprocal differences were not significant in the F2 generation seed; but were significant in four crosses in the F3 generation seed for adult bruchid emergence, suggesting that maternal effects or cytoplasmic gene effects also played a role in the inheritance of resistance to the common bean weevil. Through this study, important sources of bruchid resistance in dry bean have been identified in Malawian landraces (KK35, KK90 and KK73). These resistant sources will be used in a breeding programme to develop bruchid resistant bean cultivars, as well as improve resistance in susceptible commercial bean cultivars currently grown by farmers in Malawi. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.

Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Sitophilus zeamais is a global important pest-insect, known for the losses that it causes during production and grain storage. One of the main problems caused by synthetic pesticides use is the development of resistant insect populations. Essential oils of plants have been considered a promising alternative to the conventional management of pests insects, however, its direct application has limitations due to the instability of its composition and high volatility. According to this, the technology of nanoformulations production can increase the potential of essential oil use, and its compounds, by increasing the efficiency, and stability of these compounds. The aim of this study was evaluate the lethal and sub lethal effects of Lippia sidoides essential oil, its majoritary compound (thymol), and nanoformulations of essential oil based prototypes, under S. zeamais populations (N = 5) from different regions of Brazil. The chemical composition of the essential oil, and nanoformulation was analyzed by GC/MS/DIC. The completely random design consisted in four replications for each combination of treatment x populations of S. zeamais. Bioassays of acute toxicity were conducted in Petri dishes (6 x 1,5 cm) with 10 unsexed adults. The lethal doses (LD50 and LD90), and the lethal time (LT50) were obtained through topic application bioassays. To the nanoformulation storage efficiency was used the LD95. On the population growth, and grain consume bioassays were used different concentrations of nanoformulations to mass grain treatment. The major compound present in the L. sidoides essential oil was thymol (68.5%). During nanoformulation storage, the concentration of these compound increased, getting to 82% of the essential oil composition. L. sidoides essential oil lethal doses, needed to kill 50% of S. zeamais populations, vary between 7.1 to 19.9 μg mg-1. Jacarezinho, and Maracaju populations were, respectively, the most tolerant and susceptible populations to L. sidoides essential oil. Intermediates susceptibilities were observed to Aracaju, Rio Branco, and Sete Lagoas populations. To thymol LD50 were observed variations between 17.1 to 25.7 μg mg-1. To nanoformulations prototypes (18%) containing L. sidoides essential oil, and thymol were observed LD50 variations between 26.4 to 36 e 20.8 a 27.7 μg mg-1, respectively. L. sidoides essential oil, thymol, and their nanoformulations had a fast action under S. zeamais populations. Lethal times needed to kill 50% of the population vary between 5.8 to 62 hours. In all of those cases, the nanoformulations took longer to cause the same mortality. The nanoformulations caused mortalities higher than 80% of S. zeamais populations of over 210 storage days. Nanoformulations increasing concentrations resulted on intrinsic tax (ri), and grain consume reduction of S. zeamais populations. This study prove that nanoformulations of L. sidoides oil essential based prototypes and its majoritary compound are promising alternatives to the management of S. zeamais once these demonstrated high efficacy, low liberation of the substances, and good storage stability. / Sitophilus zeamais é uma praga de importância mundial que ocasiona danos em grãos durante sua produção e estocagem. Um dos principais problemas da utilização de inseticidas organosintéticos, usados para o controle desta praga, consiste no desenvolvimento de populações de insetos resistentes. Óleos essenciais de plantas tem sido considerados uma boa alternativa ao manejo convencional, porém sua utilização direta apresenta limitações devido à instabilidade de sua composição e a alta volatilidade. Neste sentido, a tecnologia de produção de nanoformulações pode aumentar a potencialidade do uso dos óleos essenciais e seus compostos por aumentar a eficiência e a estabilidade destes compostos. No presente estudo analisamos os efeitos letais e subletais do óleo essencial de Lippia sidoides, de seu composto majoritário (timol) e de protótipos de nanoformulações a base destes compostos sobre populações de S. zeamais (N = 5) provenientes de diferentes regiões do Brasil. A composição química do óleo essencial e da nanoformulação foram analisadas por CG/EM/DIC. O delineamento experimental inteiramente casualizado, consistiu em quatro repetições para cada combinação de tratamento x população de S. zeamais. Bioensaios de toxicidade aguda foram conduzidos em placas de Petri (6 x 1,5 cm) contendo 10 adultos não sexados. As doses letais (DL50 e DL90) e o tempo letal (TL50) foram determinados em bioensaios de aplicação tópica. Para a eficiência do armazenamento das nanoformulações utilizou-se a DL95. Nos bioensaios de crescimento populacional e consumo de grãos foram utilizadas diferentes concentrações das nanoformulações para o tratamento da massa de grãos. O composto majoritário presente no óleo essencial de L. sidoides foi o timol (68,5%). Durante o armazenamento da nanoformulação esse composto aumentou, chegando a até 82% da composição do óleo. As doses letais do óleo essencial de L. sidoides necessárias para matar 50% das populações de S. zeamais variaram de 7,1 a 19,9 μg mg-1. As populações de Jacarezinho e Maracaju foram, respectivamente, a mais tolerante e susceptível ao óleo essencial de L. sidoides. Susceptibidades intermediárias foram observadas para as populações de Aracaju, Rio Branco e Sete Lagoas. O timol apresentou DL50 que variou de 17,1 a 25,7 μg mg-1. Os protótipos das nanoformulações (18%) contendo óleo essencial de L. sidoides e timol apresentaram DL50 que variaram de 26,4 a 36 e 20,8 a 27,7 μg mg-1, respectivamente. O óleo essencial de L. sidoides, o timol e suas nanoformulações atuaram rapidamente sobre as populações de S. zeamais. Os tempos letais necessários para matar 50% das populações variaram de 5,8 a 62 horas. Em todos os casos as nanoformulações demoram mais tempo para causar a mesma mortalidade. As nanoformulações causaram mortalidades superiores a 80% nas populações de S. zeamais até 210 dias de armazenamento. Concentrações crescentes das nanoformulações ocasiononaram redução da taxa intrínseca de crescimento (ri) e do consumo de grãos das populações de S. zeamais. Este trabalho comprova que os protótipos de nanoformulação a base do óleo essencial de L. sidoides e seu composto majoritário são promissores para o manejo de populações de S. zeamais uma vez que demonstraram alta eficácia, liberação lenta das substâncias e boa estabilidade no armazenamento.

Raps (Brassica napus L.) ist heute die drittwichtigste Ölfrucht weltweit. Einer der Hauptgründe für die große Anbaubedeutung liegt in der Züchtung von Sorten mit niedrigem Gehalt an Glucosinolaten (GSL) im Samen, welche die Koppelnutzung des Öls und des Rapskuchens in der Tierfütterung möglich machte. GSL sind schwefelhaltige, sekundäre Pflanzeninhaltsstoffe und ein Charakteristikum der Familie der Kreuzblütler, zu der Raps zählt. Die Funktion der GSL in der Pflanze wird zusammen mit dem sie abbauenden Enzym Myrosinase als konstitutiver Abwehrmechanismus gegenüber unspezifischen Fraßfeinden gesehen, dem sogenannten Glucosinolat-Myrosinase System. Raps wird aber auch von Schädlingen befallen, die speziell nur Kreuzblütler als Wirtspflanzen akzeptieren. Bei einigen spezialisierten Schädlingsarten der Kreuzblütler konnte gezeigt werden, dass GSL oder ihre Abbauprodukte einen Einfluss auf das Verhalten bei der Wirtspflanzenwahl, bei der Eiablage oder beim Fraß haben können. Es besteht also die Möglichkeit, dass über GSL in der Grünmasse eine quantitative Resistenz gegenüber Schadinsekten vermittelt wird und die genetische Variation von GSL im Rapsgenpool eine natürliche Resistenzquelle darstellt. Jedoch ist die Vererbung der GSL in Blatt und Stängel im Gegensatz zu den GSL im Samen wenig untersucht. Die Zielsetzung dieser Arbeit bestand daher einerseits in der Evaluierung von GSL-Gehalten und -mustern als potentielle Resistenzfaktoren gegenüber den spezialisierten Rapsschädlingen „Großer Rapsstängelrüssler“ (Ceutorhynchus napi) und „Gefleckter Kohltriebrüssler“ (Ceutorhynchus pallidactylus) und andererseits in einer genetischen Analyse der GSL-Gehalte in Blatt und Stängel. Dazu wurden dreijährige Feldversuche an vier Standorten durchgeführt, in denen 28 genetisch sehr unterschiedliche Genotypen, darunter 15 Rapsresynthesen und 13 ältere und neuere Zuchtsorten hinsichtlich der Variation von GSL-Gehalten und –Zusammensetzungen in Grünmasse und Samen und deren Anfälligkeit gegenüber den beiden Rapsstängelschädlingen evaluiert wurden. Die Daten des Schädlingsbefalls wurden in der Abteilung Agrarentomologie erhoben und entstammen der parallel durchgeführten Dissertation von Schäfer-Kösterke (2015). Um die Selektionsmöglichkeiten auf unterschiedliche GSL-Gehalte in Samen und Grünmasse zu eruieren, wurde die Vererbung von GSL in einem weiteren Experiment mit Hilfe einer DH-Population untersucht. Die Hauptfrage dieser QTL-Kartierung war, inwieweit am GSL-Stoffwechsel beteiligte Genomregionen sich zwischen Stängeln, Blättern und Samen unterscheiden. In der Auswertung der Versuchsserie zur Variation der GSL konnte für die elf identifizierte GSL eine große genetische Variation mit hohen Heritabilitäten festgestellt werden. Als großer Einflussfaktor auf die GSL-Gehalte der Genotypen erwies sich das Entwicklungsstadium der Pflanzen: Die über 28 Genotypen gemittelten GSL-Gesamtgehalte in der Grünmasse nahmen vom ersten Probenahmetermin von 18 µmol im Schossen zum zweiten auf 4 µmol bei Blühbeginn ab. Weiterhin hatten Samen im Mittel der Genotypen um 47 µmol höhere GSL-Gehalte als die Grünmasse, und Stängel um ca. 3 µmol höhere Gehalte als Blätter. Auch die mittlere GSL-Zusammensetzung der Genotypen unterschied sich deutlich zwischen Samen und Grünmasse, jedoch nicht zwischen den zwei Probenahmeterminen. Zusätzlich hatten Standort und Jahr einen Einfluss, wobei in den Jahren 2012 und 2013 die Standorteffekte größer als die der Jahre waren. Zwischen den Pflanzenteilen Blatt und Stängel bestand eine hohe Korrelation von 0,96 für den GSL-Gesamtgehalt. Zwischen Samen und Grünmasse war die Beziehung für die GSL-Gesamtgehalte mit 0,60 weniger deutlich und für die Gruppe der indolischen GSL mit 0,14 nicht mehr vorhanden. Die komplexe zeitliche und räumliche Verteilung der GSL innerhalb der Pflanze wird im Zusammenhang mit der Bedeutung von Transportprozessen diskutiert. Bei der Untersuchung der Beziehung zwischen dem Befall durch Stängelschädlinge und GSL stellte sich heraus, dass der natürliche Schädlingsdruck im Freiland mit durchschnittlich 2,6 Rapsstängelrüsslerlarven pro Pflanze und 2,8 Kohltriebrüsslerlarven pro Pflanze sehr niedrig war. Daher konnte eine Differenzierung der Genotypen im Rapsstängelrüsslerbefall nur an einem Standort in den Jahren 2012 und 2013 statistisch abgesichert werden. Für den Kohltriebrüsslerbefall gab es an keinem Standort statistisch absicherbare, genotypische Unterschiede. In den beiden ausgewerteten Umwelten zeigten sich keine signifikanten Beziehungen zwischen GSL-Gesamtgehalt, Alkenyl-GSL, Indol-GSL oder den elf einzelnen GSL und dem Befall mit Rapsstängelrüsslerlarven pro Pflanze. Hauptkomponentenanalysen und Vergleiche zwischen unter-schiedlich stark befallenen Gruppen von Genotypen ließen ebenfalls nicht auf lineare Zusammenhänge zwischen GSL-Gehalten oder -Zusammensetzungen und der Wirtspflanzenpräferenz des Rapsstängelrüsslers oder auch des Stängelfraßes der Larven schließen. Allerdings fiel die Resynthese S30 in beiden ausgewerteten Umwelten durch eine niedrige Anzahl an Rapsstängelrüssler-larven und einen niedrigen Anteil Minierfraß auf. GSL-Zusammensetzung und GSL-Gesamtgehalt von S30 zeigten jedoch keine Besonderheiten. Für die Kartierung von am GSL-Stoffwechsel beteiligten Quantitative Trait Loci (QTL) wurden GSL in Blatt, Stängel und Samen von 120 DH-Linien der DH-Population ‚L16 x Express‘ untersucht. Die beiden Populationseltern L16 und Express unterscheiden sich nicht nur durch unterschiedliche GSL-Gesamtgehalte im Samen (L16 59,0 µmol vs. Express 26,4 µmol) und in der Grünmasse (L16 1,1 µmol vs. Express 6,2 µmol), sondern auch in der relativen Zusammensetzung von Alkenyl- und Indol-GSL (L16 31 % Indol-GSL vs. Express 10 % Indol-GSL). Die über zwei Orte gemittelten GSL-Gehalte der Population waren zum Knospenstadium in der Grünmasse mit 5,4 µmol in Stängeln und 3,7 µmol in Blättern sehr niedrig, zur Reife in den Samen mit 48,6 µmol jedoch hoch. Die Heritabilitäten der Merkmale mit signifikanter genotypischer Variation lagen im Stängel zwischen 0,64 und 0,86, im Blatt zwischen 0,55 und 0,89 und im Samen zwischen 0,70 und 0,98. Die Korrelationen der GSL-Gesamtgehalte zwischen Blatt und Stängel lag bei 0,95, diejenige zwischen Stängel (Blatt) und Samen bei 0,52 (0,53). Die erstellte Kopplungskarte enthielt 4003 SNP-Marker, deren 19 Kopplungsgruppen 2050 centiMorgan abdeckten. Der mittlere Abstand zwischen zwei Markern lag bei 2 cM. Es wurden insgesamt 115 QTL gefunden von denen 49 QTL für die GSL-Gehalte im Samen, 35 QTL für die Gehalte im Stängel und 31 QTL für die Gehalte im Blatt verantwortlich waren. Für aliphatische GSL zeigten sich drei Hauptregionen auf den Kopplungsgruppen A03, C02 und C09. Während auf A03 und C09 QTL aus allen Pflanzenteilen lokalisiert wurden, regulierten die QTL auf C02 spezifisch die Gehalte im Samen. Für Indol GSL-Gehalte von Blatt und Stängel existierten zwei Hauptregionen auf den Kopplungs-gruppen A02 und C07, welche von denen im Samen (auf A03, C02 und C05) getrennt lokalisiert waren. Die Ergebnisse zeigen, dass 1) die Akkumulation von aliphatischen und indolischen GSL durch gentrennte Genomregionen gesteuert wurde, 2) GSL-Gehalte in Blatt und Stängel durch identische Genomregionen kontrolliert wurden und 3) die GSL-Akkumulation im Samen teils von den gleichen Regionen des Genoms wie in Blatt und Stängel, teils aber auch durch für Samen spezifische Genomregionen reguliert wurde.