Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-17T13:11:21Z No. of bitstreams: 1 Indira del Carmen Molo Alvarado.pdf: 1069235 bytes, checksum: 54d92e63acb53f101863e46dc0721313 (MD5) / Made available in DSpace on 2017-03-17T13:11:21Z (GMT). No. of bitstreams: 1 Indira del Carmen Molo Alvarado.pdf: 1069235 bytes, checksum: 54d92e63acb53f101863e46dc0721313 (MD5) Previous issue date: 2006-07-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Yield of Chinese cabbage (Brassica pekinnensis) may be limited by the occurrence of soft rot caused by pectinolytic bacteria. In this study 39 isolates of bacteria causing soft rot in Chinese cabbage obtained from planting areas of Camocim de São Félix, in Pernambuco State, were identified and characterized as Pectobacterium carotovorum subsp. carotovorum (Pcc) based upon biochemical tests confirmed by PCR. The variability of these isolates was evaluated through disease epidemiological components, sensitivity to antibiotics and molecular markers. The isolates were distributed in similarity groups considering 50% of the total linkage distance by the UPGMA method. Based on epidemiological components incubation period (PI), initial severity (SEVI), final severity (SEVF) and area under the disease curve progress the 39 isolates were distributed in six similarity groups. Among the epidemiological components significant Piersoncorrelation (P≤0.05) was only found for PI and SEVI (r = -0.57). Based on sensitivity to 12 antibiotics, the Pcc were distributed in 14 groups. There were significant correlations between sensitivity to gentamicin and PI (r = -0.41), as well as between sensitivity to clindamicin and SEVF (r = -0.45). The molecular markers REP, ERIC and BOX used in Rep-PCR revealed high genetic variability among the 39 isolates since 32 similarity groups were formed. No significant correlations were found among the linkage distances registered by molecular markers and the disease epidemiological components. In a second study it was evaluated soil influence on Pcc rifampicin resistant mutant (Pcc127Rif). The extinction rate of population was calculated (TEP) and ranged from 0.0547 to 0.6327 log (CFU)/d. Six soils showed suppressiveness to Pcc127Rif while five presented conducivity. The soil groupsbased on the TEP of Pcc127Rif did not correlate with municipalities, types of vegetation cover at the sampling time or soil textural classes. Considering all soils there were no significant correlations (P≤0,05) among TEP of Pcc127Rif and chemical, physical and microbiological characteristics of soils. Considering the six more suppressive soils the TEP of Pcc127Rif significantly correlated with soil apparent density (r = 0.76), total bacterium population (r = 0.82) and Bacillus spp. (r = 0.80). The Bacillus spp. population correlated with apparent density, but not with total bacterium population. Considering the five more conducive soils there was correlation between TEP of Pcc127Rif and Bacillus spp. population (r = -0.86). The high variability among Pcc isolates points out to the necessity of great attention in studies covering identification, detection, epidemiology and control of soft rot in Pernambuco. The elevated correlation between suppressiveness of some soils to P. carotovorum subsp. carotovorum and total bacteria and Bacillus spp. populations is relevant to effective implementation of soft rot management strategies / A produção de couve-chinesa (Brassica pekinensis) pode ser limitada pela ocorrência da podridão-mole causada por bactérias pectinolíticas. No presente estudo, 39 isolados de bactérias causadoras de podridão-mole em couve-chinesa, oriundos de áreas de plantio de Camocim de São Félix, em Pernambuco, foram identificados e caracterizados como Pectobacterium carotovorum subsp. carotovorum (Pcc) por testes bioquímicos confirmados por PCR. A variabilidade desses isolados foi avaliada com base em componentes epidemiológicos da doença, sensibilidade a antibióticos e marcadores moleculares. Os isolados foram distribuídos em grupos de similaridade, considerando-se 50% da distância total de ligação pelo método UPGMA. Com base nos componentes epidemiológicos período de incubação (PI), severidade inicial (SEVI), severidade final (SEVF) eárea abaixo da curva de progresso da doença, os 39 isolados foram distribuídos em seis grupos de similaridade. Entre os componentes epidemiológicos, foi constatada correlação significativa (P≤0,05) somente de PI com SEVI (r = -0,57). Baseado na sensibilidade aos 12 antibióticos, os isolados de Pcc foram distribuídos em 14 grupos. Foram constatadas correlações significativas entre sensibilidade a gentamicina e PI (r = -0,41), bem como entre sensibilidade a clindamicina e SEVF (r = -0,45). A utilização dos marcadores moleculares REP, ERIC e BOX no Rep-PCR revelou grande variabilidade genética entre os 39 isolados, pois foram formados 32 grupos de similaridade. Não foram constatadas correlações significativas entre as distâncias de ligação registradas pelos marcadoresmoleculares e os componentes epidemiológicos da doença. Em outro estudo foi avaliada a influência dos solos na população de Pcc, utilizando-se mutanteresistente a rifampicina (Pcc127Rif). A taxa de extinção relativa da população (TEP) variou de 0,0547 a 0,6327 log (UFC)/dia. Seis solos mostraram-se supressivos a Pcc127Rif enquanto cinco evidenciaram conducividade. Os grupos de solos baseados na TEP de Pcc127Rif não apresentaram relação com os municípios de coleta, tipos de coberturas do solo na época da coleta ou classes texturais dos solos. Considerando-se todos os solos, não foram constatadas correlações significativas (P≤0,05) entre a TEP de Pcc127Rif e as características químicas, físicas e microbiológicas dos solos. Nos seis solos mais supressivos, a TEP de Pcc127Rif se correlacionou significativamente com a densidade aparente do solo (r = 0,76), populações de bactérias totais (r = 0,82) e Bacillus spp. (r = 0,80). A população de Bacillus spp. se correlacionou com a densidade aparente, mas não com a população de bactérias totais. Nos cinco solos mais conducivos houve correlação entre a TEP de Pcc127Rif e a população de Bacillus spp. (r = -0,86). A elevada variabilidadeverificada entre os isolados de Pcc aponta para a necessidade de maior atenção em estudos de identificação, detecção, epidemiologia e controle da podridão-mole em Pernambuco. A alta correlação observada entre a supressividade de alguns solos a Pcc e as populações de bactérias totais e Bacillus spp. é relevante para implementação efetiva de estratégias de manejo da doença.

The diamondback moth, Plutella xylostella (Linnaeus 1758.) (Lepidoptera: Plutellidae), is a major insect pest of Brassica crops in many parts of the world leading to economic losses amounting to an estimated US$ 4-5 billion. Although parasitoids (biological control agents) play a major role in suppressing the pest populations during November – May in South Africa, the pest reaches outbreak status during September and October due to low impact of parasitoids, which has necessitated regular application of insecticides. However, insecticide applications have often resulted in the pest developing resistance, and when coupled with the negative effects of several insecticides on parasitoids, integration of the two pest control strategies for effective management of P. xylostella population density has been difficult to achieve. One approach that has received little attention is integration of host plant resistance (bottom-up effect) and biological control (top-down effect) for effective management of P. xylostella. However, the interaction between host plants, the insect pest, and parasitoids is not simple and straight forward, as strong negative impact of host plants on fitness of the insect pest can be cascaded up the food chain and have a negative impact on a given parasitoid, which in turn may reduce the desired complementary effect between the two pest control strategies. To identify optimal interactions between cabbage (Brassica oleracea L. var. capitata, Brassicaceae), P. xylostella and its larval parasitoid Cotesia vestalis (Haliday 1834) (Hymenoptera: Braconidae), this study investigated (i) the effects of seven cabbage cultivars (Empowa, Hollywood F1, Megaton, Leano, Menzania, Beverley Hills and Karabo) on fitness parameters (survival, developmental time, pupal weights, longevity without food and oviposition rates) of P. xylostella; (ii) the influence of the same host plant cultivars on fitness parameters (developmental time, pupal weights, longevity xi without food, fecundity, emergence rate and sex ratio) of C. vestalis. Furthermore, net reproductive rates and the intrinsic rates of natural increase were calculated for C. vestalis that emerged from hosts fed on each of the cultivars. All experiments were conducted in climate-controlled laboratory rooms maintained at 22 ± 1 ºC (mean ± S.D.), 60 ± 5 % RH and 16L: 8D photoperiod. Under the no choice test, overall survival of P. xylostella immature stages was highest on Karabo (67.26%) and lowest on Megaton (44.92%). The larval and pupal developmental period, and generation time was prolonged on Empowa (18.48 days), Karabo (14.64 days) and Beverly Hills (17.48 days), while developmental period on Hollywood F1 (13.79 days) was shortest. Male and female P. xylostella pupal weights were lighter from larvae that fed on Megaton (4.13 and 4.65 mg), Menzania (4.53 and 4.91 mg), and Hollywood F1 (4.11 and 5.08 mg), whereas pupal weights from Karabo (6.0 and 6.82 mg) were the heaviest. Unfed female moths originally reared on Beverley Hills had the highest longevity (5.05 days), whereas those reared on Leano (3.54 days) and Megaton (3.89 days) had the shortest life span. Under the choice-test, P. xylostella moth laid significantly more eggs on Empowa (48.8%) and Hollywood F1 (45.6%) and least on Menzania (11.8%) and Leano (10.6%). Megaton was more resistant to P. xylostella due to lower survival rates of immature stages, lower pupal weights and moth longevity. The generation time of C. vestalis was shortest on Karabo (10.10 days) and Leano (10.38 days), and longest on Megaton (12.57 days) and Empowa (12.80 days). The highest pupal weight of C. vestalis was obtained from parasitoids reared from P. xylostella fed Menzania (5.4 mg), Megaton (5.25 mg) and Beverly Hills (4.85 mg) and the lightest on Karabo (3.8 mg). Parasitoids reared on larvae that fed on Hollywood F1 lived the longest (2.28 days) followed by Menzania (1.94 days) and Beverly Hills (1.8 days), whereas those whose hosts fed on Leano had shortest life span (0.83 days). Despite the parasitoids from Megaton hosts being heavier, their fecundity and number of female progeny per female (16.87 and 3.60, respectively) were lowest. Cotesia vestalis fecundity and daughters produced per female were highest on hosts fed on Menzania (38.00 and 9.13, respectively) and Beverly Hills (32.87 and 9.07, respectively). As a consequence, the net reproductive rate (R0) and intrinsic rate of increase (r) were higher on Menzania (7.87 and 0.58, respectively) and Beverly Hills (8.29 and 0.62, respectively). As survival and overall fitness of P. xylostella was lower on Megaton, this cultivar can play a major role in restricting population growth of this pest and thus generational number of eggs deposited on it during September and October. However, this strong bottom-up effect of Megaton on P. xylostella was cascaded up the food chain, as overall fitness of C. vestalis was lower on hosts developing on it. In contrast, the overall fitness of C. vestalis was higher on hosts that developed on Menzania and Beverly Hills. As these cultivars showed potential to sustain population density of C. vestalis at higher levels, it is also assumed that the period required for the parasitoid to reach the critical density to suppress the host population at a lower average density will be reached quicker than on other cultivars. Thus, their cultivation may improve biological control of P. xylostella during November–May in South Africa / Agriculture, Animal Health and Human Ecology / M. Sc. (Agriculture)

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The knowledge about palm (Euterpe edulis Mart.) mineral nutrition are important in the commercial scale of biomass of this specie, but there is a lack about nutritional necessities from the nursery to the production phase. The phosphorus is found in small concentrations in forest soils, affecting the vegetal species growth and production. So, the objective of this study was to evaluate the effect of phosphorus doses in the growth of young palm plants, as well as, determine the content of macro and micronutrients from the below and above ground biomass through a tissue analysis. The assay was conducted in a greenhouse. The seeds of Euterpe edulis Mart. were collected in the county of Venâncio Aires-RS. The substrate was Yellow-Reddish Argisoil collected on the first superficial layer (0 20 cm). As complement fertilizer were add 10mg Kg -1 of N and 12,5mg Kg-1 of K., the sources were (NH4)SO4 and KCL, respectively.Polypropylene vases with the capacity of 2,0 dm3 were used, which were sealed, to minimize the loss of water and nutrients. The statistical design was completely randomized with 8 treatments and 8 replicates, totalizing 64 plots. The treatments were quantitative and equidistant, constituted by: T1- control (soil without P); T2-90mg Kg-1; T3-180mg Kg-1 ; T4-270mg Kg -1;T5-360mg Kg-1; T6-450mg Kg-1; T7-540mg Kg-1; T8-630mg Kg-1 of P, respectively, using CaHPO4 as salt. The phosphorus was mixed to the soil before the sowing. After 12 months after sowing, the following variables were evaluated: above ground height, stem diameter, above ground biomass, below ground biomass, total biomass and roots length. The nutritional analysis from below and above ground biomass was done to obtain the amount of macro and micronutrients. The results show that the growth of young palm plants was achieved to the analyzed parameters, except stem diameter and root length, ranging between 450 and 540 mg de P kg-1 to the above ground height, above ground biomass and total biomass, and between 360 and 450 mg de P kg-1 to the below ground biomass. Due to the macro and micronutrients amount in the above and below ground biomass, the following sequence was established: N > Ca > K > Mg > P>S; Fe > Mn > Zn > B > Cu ; N > Ca > Mg > S > K > P; Fe > Mn > Zn > B > Cu. / Os conhecimentos de nutrição mineral de palmiteiro (Euterpe edulis Mart.) são importantes na produção em escala comercial desta espécie, no entanto faltam dados sobre sua demanda nutricional desde a fase de viveiro até a fase de produção. O fósforo encontra-se em baixa concentração nos solos tropicais, afetando o crescimento e a produção das espécies vegetais. Assim, os objetivos deste trabalho foram avaliar o efeito de dosagens de fósforo no crescimento de plantas jovens de palmiteiro, bem como, determinar o teor de macro e micronutrientes do sistema radical e aéreo destas plantas pela análise de tecidos. O ensaio foi conduzido em casa de vegetação. As sementes de Euterpe edulis Martius foram coletadas no município de Venâncio Aires, RS. O substrato utilizado foi solo do tipo argiloso-vermelho-amarelo coletado na camada superficial (0-20 cm).Como adubação complementar, foram adicionados 10mg Kg -1 de N e 12,5mg Kg-1 de K. As fontes utilizadas foram (NH4)SO4 e KCL, respectivamente.Foram utilizados vasos de polipropileno, com capacidade de 2,0 dm3 , os quais foram vedados, visando minimizar a perda de água e nutrientes. O delineamento experimental utilizado foi o inteiramente casualizado com 8 tratamentos e 8 repetições, totalizando 64 parcelas contendo uma planta cada. Os tratamentos foram quantitativos e eqüidistantes, constituídos por: T1-testemunha (solo sem adição de P); T2-90mg Kg-1; T3-180mg Kg-1 ; T4-270mg Kg -1;T5-360mg Kg-1; T6-450mg Kg-1; T7-540mg Kg-1; T8-630mg Kg-1 de P, respectivamente, utilizando CaHPO4 como sal. O fósforo foi misturado ao solo antes de ser feita à semeadura. Decorridos 12 meses da semeadura, foram avaliadas as seguintes variáveis: altura da parte aérea, diâmetro do colo, biomassa aérea, biomassa radical, biomassa total e comprimento de raízes. A análise nutricional da biomassa aérea e radical foi realizada visando a obtenção dos teores de macro e micronutrientes. Os resultados indicam que o crescimento de plantas jovens de palmiteiro (E. edulis) foi alcançado para os parâmetros avaliados, exceto diâmetro do colo e comprimento do sistema radicular, ocorrendo entre as dosagens 450 e 540 mg de P Kg-1, para altura da parte aérea, biomassa aérea e biomassa total, e entre 360 e 450 mg de P Kg-1para biomassa radical. Em relação aos teores de macro e micronutrientes na biomassa aérea e radical estabeleceu-se a seguinte seqüência respectivamente: N > Ca > K > Mg > P>S; Fe > Mn > Zn > B > Cu ; N > Ca > Mg > S > K > P; Fe > Mn > Zn > B > Cu.

A agregação em insetos centra-se nas vantagens relativas ao forrageio e no aumento da defesa contra predadores. Além disso, agregações de ovos podem beneficiar-se pelo aumento nas taxas de eclosão larval. Neste trabalho, foram testadas as hipóteses de que agregações de Ascia monuste orseis (Godart, 1819) (Lepidoptera: Pieridae) uma espécie que se alimenta em agregações larvais em plantas da família Brassicaceae - conferem benefícios à performance larval e adulta, na assimilação de alimento pelas larvas, na viabilidade dos ovos e na proteção larval contra inimigos naturais. A possibilidade de um dado comportamento do grupo resultar em maior ataque por inimigos naturais também foi avaliada, bem como um padrão comportamental defensivo em resposta aos inimigos naturais. Para tanto, quatro tratamentos de diferentes tamanhos de agregações larvais foram formados (1, 7, 15 e 30 larvas) para avaliar a performance e a assimilação de alimento em laboratório. Em campo, três tratamentos foram formados (1, 10 e 50 larvas) para testar o efeito do tamanho do tamanho do grupo na predação e parasitismo. A performance do estágio de ovo foi examinada em posturas de tamanhos variados em casa de vegetação. Larvas gregárias desenvolveram-se mais rápido nos ínstares iniciais e tornaram-se fêmeas mais fecundas em comparação às solitárias; entretanto, larvas solitárias apresentaram maior tamanho do que as gregárias. A sobrevivência não diferiu entre os tratamentos em laboratório. Foi observado um menor consumo per capita de alimento por larvas gregárias, sem custos para a assimilação de alimento. A viabilidade dos ovos aumentou com o tamanho da agregação de ovos, comprovando o benefício da agregação larval na fase de ovo. A menor predação per capita em agregações larvais maiores conferiu uma maior proteção às larvas de A. monuste orseis contra predadores e parasitoides, através do efeito da diluição do ataque entre os indivíduos do grupo. O parasitoidismo foi mais expressivo em larvas de primeiros ínstares, enquanto que larvas mais tardias foram mais atacadas por predadores, independente do tamanho da agregação. Por fim, eventos comportamentais que envolvem movimentação da cabeça como exploração e alimentação foram mais perigosos para as larvas de A. monuste orseis em comparação ao repouso e deslocamento, semelhantemente a espécies de hábito solitário. Eventos comportamentais supostamente defensivos foram observados em todos os ínstares e tratamentos. As vantagens da agregação em A. monuste orseis mostraram-se especialmente importantes no estágio de ovo e primeiros ínstares, pela diminuição da mortalidade de ovos e vulnerabilidade larval aos inimigos naturais. Esses benefícios provavelmente sobrepõem-se aos custos, como a competição por interferência observada entre as larvas no final do desenvolvimento. Nossos resultados mostram que o malogro dos ovos e os efeitos dos inimigos naturais constituem fortes pressões seletivas na manutenção da agregação de ovos e larval em A. monuste orseis, a qual confere uma melhor performance do ponto de vista bi-trófico, bem como maior probabilidade de sobrevivência individual sob o ponto de vista tri-trófico. / In insects, the gregarious habit has been shown to improve foraging and defense against predation to both larval and adult stages. Egg clusters could also be beneficial through increased larval hatching. In this study, we tested the hypothesis that egg clusters and larval aggregations of the neotropical butterfly Ascia monuste orseis (Godart, 1819) (Pieridae) - a subspecies that uses Brassicaceae as hosts - lead to several benefits from both bi- and tri-trophic perspectives. Larval and adult performances, food assimilation by the larvae, egg viability, as well as protection against natural enemies were assessed from individuals reared either isolated or aggregated. The behavior of larval aggregations was also examined with respect to predation risk, as well as the corresponding larval defensive behaviors after enemy attack. Four treatments with different larval aggregation sizes were assigned (1, 7, 15 e 30 larvae) to assess larval performance and food utilization in the laboratory. In the field, three treatments were assigned (1, 10 e 50 larvae) to evaluate the effects of group size on predation and parasitoidism. Egg performance was examined through egg clusters of different sizes in a greenhouse. Gregarious larvae developed faster, especially in early instars, and became more fecund females than solitary larvae; however, the latter attained larger body size than the former. Under laboratory conditions, survival did not differ among treatments. Lower food ingestion per capita was observed in gregarious larvae, with no cost in food assimilation. The viability of eggs increased as egg aggregation size increased. The lower per capita predation in larger larval aggregations than smaller groups conferred higher protection to A. monuste orseis larvae against natural enemies, through the dilution effects among individuals of the group. Parasitoidism was more intense in small-sized larvae while late instars were more susceptible to predators, regardless of aggregation size. Similar to species with solitary habit, behavioral events which involved head movements as searching and feeding were more dangerous to A. monuste orseis larvae compared to resting and walking. Presumed defensive behaviors were observed in all instars and treatments. Thus, the benefits of aggregation in A. monuste orseis can be seen especially in the egg stage and in first instars, as it reduces egg mortality and larval vulnerability to natural enemies. These benefits probably overcome some costs, such as interference competition in the late instars. Taken together, the results show that egg failure and top-down effects constitute selective pressures in maintaining egg and larval aggregation in A. monuste orseis, by providing better performance from a bi-trophic perspective and increased probability of individual survival from a tri-trophic perspective when compared to solitary individuals.

Hyperparasitism of beneficial parasites of Pieris rapae was studied on Brassica crops in Montgomery County, Virginia. The goal of the study was to determine whether the hyperparasites attacking the larval parasites of P. rapae were capable of eliminating an introduced population of the larval parasite Cotesia rubecula (Marshall) (Hymenoptera: Braconidae). Pieris rapae was found to be active from April to November with possibly six generations per year in this region. It was attacked throughout this period by five generations of the larval parasite Cotesia glomerata (L.) (Hymenoptera: Braconidae). Although P. rapae larvae were twice as numerous on broccoli (var. Premium Crop) than on cabbage (var. Rio Verde), a higher proportion of P. rapae larvae was parasitized by C. glomerata on cabbage, indicating that C. glomerata preferred to forage for P. rapae in cabbage. In spring plantings, up to 36.9% of C. glomerata cocoon masses had been affected by the hyperparasite T. galaetopus (Ratzeburg) (Hymenoptera: (Eulophidae) and 23.3% by the hyperparasite Spiloehaleis torvina Cresson (Hymenoptera: Chalcididae). In the fall, 93.2% and 4.2% of the cocoon masses were affected by T. galaetopus and S. torvina, respectively. Tetrastiehus galaetopus activity was observed from May to November, but it was most active after mid July. Tetrastiehus ga/aetopus had little impact on the gregarious C. glomerata, and even though it could affect >90% of the C. glomerata cocoon masses for extended periods, 500/0 of the cocoons in each mass were unaffected. However, it's high reproductive capacity could adversely affect a solitary host such as C. rubecula. Spilochalcis torvina was observed as early as late May but it was most active during the mid summer months. It's reproductive activity ceased by early October even though hosts were abundant in the month which followed. Four generations were seen between June and October. Spilochalcis torvina's hosts were Cotesia orobenae Forbes (Hymenoptera: Braconidae), C. glomerata, and Plutella xylostella (L.) (Lepidoptera: Plutellidae), but the principal host was C. glomerata. However, the proportion of female S. torvina progenies was <31% from the Cotesia spp. hosts and 70% from P. xylostella hosts. Spilochalcis torvina typically hyperparasitized <4 pupae per Cotesia spp. cocoon mass in the field. In laboratory experiments, S. torvina hyperparasitized an average of <7 C. rubecula pupae daily, and the maximum number hyperparasitized was 12. Due to its apparently low reproductive rate in the laboratory, and its low rate of hyperparasitization on hosts in the field, it is unlikely that S. torvina is a danger to populations of parasites like C. rubecula. / Master of Science

Invasive alien species is one of the biggest threats to biodiversity worldwide. American Skunk-cabbage (Lysichiton americanus) is an invasive alien plant originating from North America. It has become naturalised in several European countries, including Sweden. American Skunk-cabbage is a threat to other plants as it forms dense stands and outcompetes native vegetation by shadowing. It is believed that the biggest population of Skunk-cabbage in Sweden is along Fylleån in Halland. The aim with this report is to map the distribution of Skunk-cabbage in a section of the stream and to examine different methods for control and eradication of the weed. A survey was performed along a section of the stream between the dates 30th April – 8th May 2019. The survey was executed from Ryaberg to Torsaberga (13 km). The search area was comparted into 6 locations. The highest point where Skunk-cabbage was found upstream in Fylleån was at location 6. A total of 4157 individual plants were found along a stretch of 6km and 34 km of the stream is believed to be affected by the invasion. A majority of the plants grows in marshland. Both mechanical and chemical control are used when eradicating Skunk-cabbage. The most common method is digging by hand. This is also the method that I recommend in the event of an eradication campaign in Fylleån. No eradication efforts will be performed in Fylleån during 2019 due to restricted economical resources. Different projects are under development for the purpose of future eradication of Skunk-cabbage in Halland. / Invasiva främmande arter är ett av de största hoten mot biodiversiteten globalt. Gul skunkkalla (Lysichiton americanus) är en invasiv främmande växt från Nordamerika. Arten är naturaliserad och etablerad i flera europeiska länder, däribland Sverige. Skunkkalla har en förmåga att konkurrera ut andra arter genom skuggning. Den bildar täta och stora bestånd och tränger på så vis undan annan växtlighet. Sveriges största bestånd av skunkkalla förmodas finnas längs med Fylleån i Hallands län. I bevarandeplanen för Natura 2000-området Fylleån finns en punkt om att man behöver ta ställning till de stora bestånden av skunkkalla i ån. Den här rapporten behandlar både utbredning och kartläggning av skunkkalla i en utvald del av Fylleån, samt bekämpningsmetoder för arten. Kartläggning av utbredningen har skett genom en inventering längs med ån. Inventeringen utfördes mellan Ryaberg och Torsaberga (13km) mellan datumen 30/4 – 8/5 2019. 4157 plantor av skunkkalla hittades längs en sträcka av 6km mellan Ryaberg och Fröbökekvarn. Fyndplatserna delades in i 6 lokaler. Lokal 6 är den högsta fyndplatsen av skunkkalla i Fylleåns lopp. 3,4 mil av ån bedöms vara påverkad av invasionen. Den vanligaste växtplatsen längs med ån bedöms vara sumpmark. I bekämpning av skunkkalla använder sig av både mekanisk och kemisk bekämpning. Den vanligaste använda bekämpningsmetoden visade sig vara bortgrävning för hand. Det är också den metoden jag förespråkar vid en eventuell utrotning i Fylleån. På grund av brist på ekonomiska resurser kommer inte någon utrotning att ske i Fylleån 2019. Olika projekt är nu under konstruktion för framtida bekämpning i länet.

O presente trabalho teve por objetivo identificar fragmentos homólogos a genes de resistência em Brassica oleracea e Zea mays, por meio da amplificação por PCR, utilizando oligonucleotídeos homólogos a regiões conservadas de genes de resistência de plantas. Em B. oleracea, os oligonucleotídeos foram desenhados com base na seqüência de um gene homólogo ao RPS2 de Arabidopsis thaliana descrito em B. oleracea. Um fragmento de 2,5 Kb foi amplificado em duas linhagens. Os fragmentos amplificados apresentaram polimorfismo de comprimento entre as linhagens, gerando um marcador molecular. Este marcador foi utilizado em uma população F2 segregante para resistência a Xanthomonas campestris pv. campestris oriunda do cruzamento entre as linhagens BI-16 e Lc201. O marcador, no entanto, não apresentou-se ligado a nenhum gene de resistência a este patógeno. Análise da expressão por meio de RT-PCR detectou a expressão do fragmento homólogo nas linhagens resistente e suscetível de B. oleracea com e sem inoculação, indicando que o gene é expresso constitutivamente. Em Z. mays, oligonucleotídeos sintetizados com base em seqüências de milho homólogas a genes de resistência, denominadas Pics, e a ESTs de milho, também homólogos a genes de resistência, foram utilizados para amplificação em linhagens resistente e suscetível a Exserohilum turcicum, Colletotrichum graminicola e Phaeosphaeria maydis. Um par de oligonucleotídeos amplificou um fragmento polimórfico entre as linhagens resistente e suscetível a E. turcicum. Este foi utilizado em uma população segregante, mas também não observou-se ligação com o gene Ht de resistência a E. turcicum. Nas demais linhagens, os fragmentos foram monomórficos. Os oligonucleotídeos baseados em ESTs amplificaram fragmentos em todas as linhagens parentais. Esses fragmentos foram digeridos com enzimas de restrição, mas não apresentaram polimorfismo entre nenhuma das linhagens. Os resultados indicaram que a estratégia de utilização de seqüências conservadas é eficiente para amplificação de genes homólogos. O polimorfismo entre estes homólogos pode ser usado como marcador molecular para detecção de genes de interesse. Todavia, nem sempre estes marcadores estão ligados a esses genes. / The aim of this work was to identify homologs of resistance genes in Brassica oleracea and Zea mays by PCR amplification using primers based on conserved domains of plant resistance genes. In B. oleracea, the primers were based on the sequence of a homolog of the Arabidopsis thaliana RPS2 gene previously described in B. oleracea. A 2.5 Kb fragment was amplified on two lines. These fragments showed length polymorphisms between lines, based on which a molecular marker was developed. This marker was used in a F2 population, derived from the crossing between the inbred lines BI-16 and Lc201, and which segregates to resistance to Xanthomonas campestris pv. campestris. The marker, however, was not linked to any Xcc resistance gene. Expression analyses by RT-PCR detected the expression of these homologs on both resistant and susceptible lines with and without inoculation, indicating that the gene is constitutively expressed. In Z. mays, primers based on resistance gene homologs sequences, named Pics, and on maize ESTs homologous to disease resistance genes, were used to amplify genomic fragments on resistant and susceptible lines to Exserohilum turcicum, Colletotrichum graminicola and Phaeosphaeria maydis. A set of primers amplified a polymorphic fragment between lines resistant and susceptible to E. turcicum. This fragment was used in a segregating population, but no linkage was detected between this marker and the E. turcicum resistance gene Ht. Among the other lines, the fragments were not polymorphic. The primers based on ESTs amplified fragments on all parental lines. These fragments were digested with restriction enzymes but did not reveal any polymorphism between lines. The results indicated that the strategy of using conserved sequences is efficient to amplify disease resistance gene homologs. The polymorphism among these homologs may be used as a molecular marker, but these markers are not always linked to disease resistance genes.

The cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), is an important pest of brassicaceous oilseed crops, especially canola (Brassica napus L. and Brassica rapa L.) in North America and Europe. Application of foliar insecticide is the only method currently employed to control C. obstrictus populations; because this approach is environmentally unsustainable, alternatives including host plant resistance have been explored. White mustard, Sinapis alba L., is resistant to C. obstrictus and was chosen as a potential source of resistance for B. napus oilseed. Interspecific crosses of S. alba x B. napus have produced several lines that are resistant to C. obstrictus feeding and oviposition and yield fewer, lighter-weight weevil larvae that take longer to develop. I investigated potential mechanisms of this resistance, including assessing differences in visual and olfactory cues among resistant and susceptible genotypes, and antixenosis and antibiosis. Determining effects of visual cues associated with host plant resistance required investigation of weevil vision. Deployment strategies for resistant germplasm were assessed to evaluate incorporation of susceptible refugia to promote long-term durability of resistance traits. Results reported in Chapter 2 indicate that the C. obstrictus visual system is apparently trichromatic and incorporates receptors with response maxima near 350, 450, and 550 nm. Modelling indicated that UV light alone reduced weevil responses but the interaction of yellow and UV light increased responses at a threshold reflectance level of UV. Results reported in Chapter 3 indicated that differences in yellow and UV reflectance among host plant flowers influence host selection in C. obstrictus. Results described in Chapter 4 determine differential attraction to the odours of S. alba and B. napus and among resistant and susceptible accessions. Inferences of the identities of glucosinolates found in varying amounts among susceptible and resistant genotypes suggested that 2-phenylethyl glucosinolate influenced attractiveness. Results described in Chapter 5 indicate differences in adult feeding and oviposition preferences among resistant and susceptible genotypes. Oocyte development, larval biomass and larval development time varied among weevils feeding on resistant and susceptible genotypes. Based on results of Chapter 4, 1-methoxy-3-indolylmethyl glucosinolate was implicated as contributing to antixenosis and antibiosis resistance. Results reported in Chapter 6 describe effects of mixed plots of resistant and susceptible genotypes on weevil spatial distribution and oviposition. These results are consistent with associational resistance and attributed to reduced apparency of susceptible plants in mixtures and antixenosis resistance associated with resistant germplasm. / Plant Science

This research was conducted in order to evaluate natural trace element (TE) contents and anthropogenic contamination in soils and vegetables in Chenggong County (Yunnan Province, China). In this way, trace element contents in soils have been analysed to assess TE contamination in soils and vegetables, and transfer of TE from soil to vegetables. Agricultural practises have been proposed to amend the quality of vegetables. We identified three geomorphopedological units: lacustrine unit, transition unit and mountain unit.  In the mountain unit, soil texture is clay more often from the weathering of limestone and marlstone. Soil colour is red or reddish brown with acid reaction.  In the transition unit, soil texture is loamy clay. Soil colour is red-brown with acid reaction.  In the lacustrine unit, soil texture mainly is sandy developed from lacustrine-alluvial deposits. Soil colour is brown and is slightly acid. Total TE contents in the topsoil are higher than usual and even Kunming Prefecture soil. TE contents indicate a high contaminated level when considered globally. Pb, Cd and Zn present however individually low contaminated levels, and Cu presents a medium contaminated level. TE contents decrease from northeast to southwest, which is consistent with the elevation gradient. Significant differences of TE contents are observed according to distance from Chenggong town in the lacustrine unit and with distance from the mountain in the transition unit. TE accumulation is usually observed along roads. TE contents in subsoil are related to soil colour, texture, parent materials and mottles. Accumulation of Pb and Zn in topsoil and of Cu and Cd in subsoil are observed. The highest contents are observed for Pb in cauliflower, Cd in lettuce and Chinese cabbage, and Cu and Zn in pea. The order of TE accumulation in plants varies according to the plant species and organ. According to relations between TE contents in Chinese cabbage and extraction sequential fractions of TE in soils, different soil fractions are suggested as soil assessment indicators. Lime and pig manure have been applied to modify the soil pH and to decrease the mobility of TE in situ. With increasing in lime rate and pH, contents of acetic-acid extractable TE fractions in soil decrease. Enrichment coefficients related to TE availability (AEC) of Pb and Cu are stable and are not changed by lime or pig manure. AEC of Cd and Zn which are high in low pH, decrease with increased pH and application rates of lime and pig manure. When application rates of lime and pig manure increase, TE contents in Chinese cabbage decrease and biomass of Chinese cabbage increases. Application rates of lime and pig manure are recommended, but their quality should also be taken into account. / Cette recherche a pour objet l'étude de la teneur naturelle en éléments traces métalliques (ET) et de la contamination anthropique des sols et des productions légumières dans le Comté de Chenggong (Province du Yunnan, RP de Chine). Pour cela, la variabilité des teneurs en fonction des conditions géomorphopédologiques a été analysée, ainsi que les transferts des ET du sol vers les végétaux. Cette approche a permis ensuite d'aborder l'évaluation de la qualité des sols et des légumes, puis de proposer des pratiques agricoles alternatives dans le but d'améliorer la qualité des légumes produits. La zone d'étude a été divisée en 3 unités géomorphopédologiques: unité de montagne où les sols brun rouge à rouge résultent notamment de l'altération de calcaires et de marnes. Une texture argileuse et une réaction acide dominent. unité de piedmont (dite de transition) où les sols de couleur jaune clair à jaune rougeâtre résultent principalement de l'altération de grès et de shales. Une texture limono-argileuse en surface et argileuse en profondeur, ainsi quune réaction acide dominent. unité lacustre, à proximité du Dianchi Lake, dont les sols de couleur brun foncé sont essentiellement développés à partir de sédiments lacustres. Une texture sableuse domine en surface, ainsi qu'une réaction faiblement acide à neutre. Les teneurs en ET rencontrées en surface des sols de la zone d'étude sont plus élevées que les teneurs moyennes observées dans les sols du monde ou même de la préfecture de Kunming. Evaluées séparément pour chaque ET, les teneurs rencontrées correspondent à des niveaux de contamination jugés faibles pour Pb, Cd et Zn, moyen pour Cu. Considérées simultanément, ces teneurs permettent de déterminer un indice de contamination global correspondant à un niveau de contamination élevé. Les teneurs en ET décroissent globalement du nord-est vers le sud-ouest, suivant le gradient d'altitude. Ces teneurs varient également de façon significative en fonction de l'éloignement de la montagne dans l'unité de transition et de l'éloignement de l'agglomération de Chenggong dans l'unité lacustre . Une accumulation en ET est souvent observée le long des routes. Dans le sous-sol, les teneurs en ET sont liées à la couleur, à la texture, au matériau parental, et aux marques d'altération. Les teneurs sont plus élevées en surface pour Pb et Zn, et en profondeur pour Cu et Cd. Les teneurs les plus élevées pour Pb sont observées dans le chou-fleur, pour Cd dans la laitue et le chou chinois, pour Cu et Zn dans le pois.L'ordre d'accumulation des ET dans la plante dépend de l'espèce et de l'organe considérés. En fonction des corrélations observées entre les teneurs du chou chinois et les résultats obtenus avec différentes modalités d'extraction des ET du sol, des indicateurs d'évaluation de la qualité du sol ont été proposés. Un amendement carbonaté et du fumier de porc ont été épandus afin de réduire in situ la mobilité des ET. L'augmentation de l'apport d'amendement carbonaté permet d'augmenter le pH du sol et de diminuer la fraction extraite avec l'acide acétique dilué (AA) pour chaque élément. Les AEC, rapports teneur dans la plante : teneur dans le sol extractible à lAA, sont stables pour Pb et Cu et ne sont modifiés par aucun des 2 apports. Cependant, les AEC de Zn et de Cu, élevés quand le pH du sol est acide, diminuent si le pH devient plus alcalin, ainsi qu'avec les apports d'amendement carbonaté et de fumier de porc. Quand les apports d'amendement carbonaté et de fumier de porc augmentent, les teneurs en ET du chou chinois diminuent et sa biomasse augmente. Un épandage d'amendement carbonaté est donc recommandé. Cependant la plus grande attention doit être portée à la qualité des fumiers de porcs dont les teneurs en Zn et Cu ne sont pas négligeables.

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