[EN] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) is a new citrus pest in the Mediterranean basin. Nymphs of P. kellyanus refuge and feed on the surface of young fruitlets. This feeding habit causes rings of tissue scar around the apex as fruit mature and leads to economic losses because of the reduced market value of the affected fruit. Despite the worldwide distribution and economic importance of P. kellyanus, its biological control is still under development and chemical control is the only alternative for growers. In order to improve the integrated management of P. kellyanus we determined the seasonal trend of P. kellyanus nymphs during the period in which the young fruitlets are sensitive to thrips damage. We studied the diurnal distribution of ¿rst and second generation P. kellyanus nymphs, as well as, the spatial distribution within the tree of the nymphs and damages. These results will improve the sampling protocols and the insecticide applications. The seasonal trend (number of generations attacking the fruit) and damages of P. kellyanus nymphs depended on the orchards and years. This result emphasizes the importance of sampling weekly from petal until six weeks later. Furthermore, according to the data obtained, when there is a second generation of P. kellyanus nymphs, this is generally more damaging. Pezothrips kellyanus nymphs showed a clear preference for fruit located at the top of the trees, which coincided with the highest percentage of damaged fruit in this area. P. kellyanus nymphs were uniformly distributed and the cardinal directions and time of day does not seem to be an important factor to develop a sampling plan or to spray insecticides. The next objective was to determine the efficacy of three insecticides (chlorpyrifos, spinosad and spirotetramat) to control P. kellyanus nymphs. These insecticides were selected because of their different mode of action. Chlorpyrifos and spinosad significantly reduced the percentage of damaged fruit when there was one generation of nymphs. However, their persistence was not enough to prevent the attack of a second generation of nymphs. Spirotetramat had not a shock effect against this pest and it could not avoid the attack of a second generation. We analysed the side effects of these three insecticides on natural enemies present at the time of the treatment. Spinosad as spirotetramat negatively affected phytoseiids. Due to low populations of other natural enemies we could not assess the side effects on them. Therefore, we decided to study the side effects of these insecticides on coccinelids and parasitoids under laboratory conditions. Lethal and sublethal side effects of spirotetramat on adults and larvae of Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) were evaluated under laboratory conditions by topical application and by ingestion of treated individuals of Planococcus citri Risso (Hemiptera: Pseudococcidae). Spirotetramat resulted harmless when directly applied on larvae and adults of C. montrouzieri, since it did not affect survival, longevity, fecundity, egg hatching, and offspring survival. When larvae and adults of C. Montrouzieri were fed with treated prey, spirotetramat was also classified as harmless. We studied lethal and sublethal effects of spirotetramat, spinosad and chlorpyrifos on Aphytis melinus DeBach (Aphelinidae Hymenoptera), the main parasitoid of Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae). For A. melinus adults, chlorpyrifos and spinosad were classified as toxic but spirotetramat resulted moderately toxic. For immature (larvae), chlorpyrifos was moderately toxic, spirotetramat was slightly toxic and spinosad resulted harmless. Takin into consideration these results, spirotetramat could be used against P. kellyanus in orchards where population levels are low and an application against A. aurantii is also need because this insecticide shows high efficacy against this pest. / [ES] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) es actualmente una plaga más en los cítricos valencianos, cuyas ninfas, al alimentarse de la superficie de los frutos recién cuajados, producen unas escarificaciones circulares alrededor del pedúnculo que devalúan el valor del fruto en el mercado. Hoy en día, el control químico es prácticamente la única alternativa contra este trips. Para mejorar la gestión integrada de P. kellyanus es necesario un mayor conocimiento sobre su biología y ecología en campo. Para ello, se ha seguido la dinámica poblacional de las ninfas de P. kellyanus durante el periodo en que los frutos recién cuajados son más sensibles a los daños producidos por las ninfas. Se ha estudiado la distribución de la plaga dentro de los árboles y su movimiento a lo largo del día, factores necesarios para estimar la población de trips y para afinar las aplicaciones de productos fitosanitarios. Tanto la dinámica como los daños variaron según parcelas y años. Tras la caída de pétalos se observaron una o dos generaciones de ninfas que produjeron daños en los frutos. Resultado que subraya la necesidad de realizar muestreos semanales desde la caída de pétalos hasta incluso después del tratamiento contra la primera generación. Además, según los datos obtenidos, cuando se da una segunda generación de P. Kellyanus, ésta es más dañina para los frutos. Las ninfas de P. kellyanus mostraron una preferencia por los frutos situados en la parte alta de la copa, coincidiendo con el mayor número de frutos dañados en esta zona. La distribución de las ninfas fue uniforme en las cuatro orientaciones del árbol y a lo largo del día. Por lo tanto, estos factores no parecen ser claves a la hora de desarrollar un plan de muestreo o realizar aplicaciones fitosanitarias. A continuación se determinó la eficacia de tres insecticidas (clorpirifos, spinosad y spirotetramat), con diferente modo de acción, en el control de las ninfas de P. kellyanus. Clorpirifos y spinosad redujeron significativamente el porcentaje de frutos dañados cuando se dio una sola generación de ninfas P. Kellyanus, sin embargo no evitaron el ataque de una segunda generación de ninfas. Spirotetramat no presentó un efecto de choque y no evitó el segundo ataque. En estos trabajos de campo, se analizaron los efectos secundarios de los insecticidas sobre los enemigos naturales presentes en el momento de los tratamientos. Spinosad como spirotetramat afectaron negativamente a las poblaciones fitoseidos en campo. Debido a las bajas poblaciones del resto de enemigos naturales no pudo evaluarse los efectos secundarios sobre ellos y se estudiaron en condiciones de laboratorio sobre coccinélidos y parasitoides. Se determinaron los efectos letales y subletales de spirotetramat en adultos y larvas de Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae), por aplicación directa de los productos y por ingestión de presa, Planococcus citri Risso (Hemiptera: Pseudococcidae), previamente tratada por los productos. Spirotetramat resultó inocuo al aplicarse directamente sobre larvas o adultos de C. montrouzieri, y no afectó a la supervivencia, longevidad fecundidad, fertilidad y y supervivencia de la descendencia. Spirotetramat también resultó inocuo al alimentar a adultos y larvas de C. montrouzieri con presa previamente tratada. Se determinaron los efectos letales y subletales de los tres insecticidas sobre Aphytis melinus DeBach (Hymenoptera: Aphelinidae), principal parasitoide de Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae) en cítricos. En adultos, clorpirifos y spinosad resultaron tóxicos mientras que spirotetramat resultó moderadamente tóxico. Sobre inmaduros de A. melinus, clorpirifos resultó moderadamente tóxico, spirotetramat ligeramente tóxico y spinosad inocuo. Así, spirotetramat se podría utilizar contra P. kellyanus en parcelas con niveles poblacionales bajos cuando deba tratarse también cont / [CAT] Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae) és, actualment, una plaga més dels cítrics valencians. Les nimfes es refugien i s'alimenten de la superfície dels fruits recentment quallats que produeix unes escarificacions circulars al voltant del peduncle del fruit i devaluen el seu valor al mercat. Hui en dia, el control químic és pràcticament l'única alternativa contra aquest trips. Per poder millorar la gestió integrada de P. kellyanus és necessari un major coneixement sobre la seua biologia i ecologia en camp. Per a això, s'ha avaluat la dinàmica poblacional de les nimfes de P. kellyanus durant el període on els fruits recentment quallats són més sensibles als danys produïts per les nimfes. A més, s'ha estudiat la distribució de la plaga dins dels arbres i el seu moviment al llarg del dia, factors necessaris per a estimar la població de trips i per afinar les aplicacions de productes fitosanitaris. Tant la dinàmica com els danys van variar segons parcel¿les i anys, després de la caiguda de pètals es van observar una o dues generacions de nimfes que van produir danys als fruits. Aquest resultat subratlla la necessitat de realitzar mostrejos setmanals des de la caiguda de pètals fins i tot després del tractament contra la primera generació. Segons les dades obtingudes, quan es dóna una segona generació de P. kellyanus, aquesta és més perjudicial per als fruits. Les nimfes van mostrar un clara preferència pels fruits situats a la part alta de la copa, coincidint amb el major nombre de fruits danyats en aquesta zona. No obstant això, la distribució de les nimfes va ser uniforme en les quatre orientacions de l'arbre i la seva abundància tampoc va variar al llarg del dia. Per tant, son factors que no semblen ser claus a l'hora de desenvolupar un pla de mostreig o realitzar aplicacions fitosanitàries. El següent objectiu va ser determinar l'eficàcia de tres insecticides (clorpirifos, spinosad i spirotetramat), amb acció diferent, en el control de les nimfes de P. kellyanus. Clorpirifos i spinosad van reduir significativament el percentatge de fruits danyats quan es va donar una sola generació de nimfes, però no varen evitar l'atac d'una segona generació de nimfes. Spirotetramat no va presentar un efecte de xoc contra aquesta plaga i tampoc va evitar l'atac d'una segona generació. En aquests treballs de camp, se va analitzar els efectes secundaris d'aquests tres insecticides sobre els enemics naturals presents en el moment dels tractaments. Spinosad i spirotetramat van afectar negativament les poblacions fitoseids en camp. Com varen ser baixes les poblacions de la resta d'enemics naturals es va estudiar els efectes secundaris sobre coccinélids i parasitoids en condicions de laboratori. Es varen determinar els efectes letals i subletals de spirotetramat en adults i larves de Cryptolaemus montrouzieri Mulsant (Coleoptera: Coccinellidae) per aplicació directa dels productes i per ingestió de presa, Planococcus citri Risso (Hemiptera: Pseudococcidae), prèviament tractada pels productes. Spirotetramat va resultar innocu a la aplicació directa sobre larves o adults de C. montrouzieri, no va afectar la supervivència, longevitat fecunditat, fertilitat i supervivència de la descendència. I el mateix quan adults i larves de van ser alimentats amb presa prèviament tractada. Finalment, es van determinar els efectes letals i subletals dels tres insecticides sobre Aphytis melinus DeBach (Hymenoptera: Aphelinidae), principal parasitoid de Aonidiella aurantii (Maskell) (Hemipteta: Diaspididae) en cítrics. En adults, clorpirifos i spinosad van resultar tòxics, spirotetramat va resultar moderadament tòxic. Sobre immadurs de A melinus, clorpirifos va resultar moderadament tòxic, spirotetramat lleugerament tòxic i spinosad innocu. Així, spirotetramat es podria utilitzar contra P. kellyanus en parcel¿les amb nivells poblacionals baixos aprofitant el tractament contra A. aurantii al p / Planes Insa, L. (2016). BASES PARA LA GESTIÓN INTEGRADA DE PEZOTHRIPS KELLYANUS (BAGNALL) (THYSANOPTERA: THRIPIDAE) EN CÍTRICOS [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63676 / TESIS

No description available.

Thesis (DPhil)--University of Stellenbosch, 2008. / ENGLISH ABSTRACT: Sub-Antarctic islands represent the only mid to high latitude terrestrial biomes in the Southern Hemisphere. These islands have various geological origins and histories, well-preserved terrestrial ecosystems and high levels of species endemism. In an attempt to understand the evolution and biogeography of terrestrial taxa in the South Polar Region, the first broad-scale molecular phylogeny was constructed for the unique terrestrial group, the ameronothroid mites (genus Halozetes (Oribatida)), collected from sub-Antarctic and Maritime Antarctic localities. Phylogenetic analyses based on a combined mitochondrial (cytochrome oxidase subunit I (COI)) and nuclear (histone-3 (H3)) sequence dataset indicated that the evolution of these mites were habitat specific (i.e. intertidal, supralittoral and terrestrial). Notwithstanding criticisms levelled against a molecular clock, the mites were evolutionary young (<10myo), contrary to their status as an ancient group predating Gondwana fragmentation. Biogeographic analyses indicated a complex pattern mainly sculpted by multiple independent dispersal events across the Antarctic Polar Frontal Zone similar to previous findings for other marine and terrestrial taxa. Also, the molecular phylogeny displayed considerable discourse with contemporary taxonomy suggesting the need for taxonomic revisions and reassessment of morphological characters. Sub-Antarctic Marion Island, the larger of the two islands comprising the Prince Edward Island archipelago (PEI), has experienced extensive glaciation and volcanism. To assess the impact of historical events (volcanism (including recent eruptions) and glaciation) and contemporary mechanisms (gene flow) on the genetic spatial distribution of species from Marion Island, two mite species namely Eupodes minutus (Prostigmata) and Halozetes fulvus (Oribatida) as well as a single plant species, Azorella selago (Apiaceae), were selected as model organisms. For independent phylogeographic analyses, mitochondrial sequence data (COI) were obtained for both mite species, while chloroplast sequence (trnH-psbA) and amplified fragment length polymorphism (AFLP) data were generated for the cushion plant, A. selago. Since A. selago is typified by two growth forms namely discrete cushions and continuous mats, it was essential to examine the growth dynamics prior to phylogeographic analyses. The sequence and fragment data indicated that both mite and plant species were significantly substructured across Marion Island. Manual comparisons indicated unique populations on the western (Kaalkoppie for H. fulvus, La Grange Kop for E. minutus and Mixed Pickle for A. selago), eastern (Bullard Beach for H. fulvus and Kildalkey Bay for E. minutus), northern (Middelman and Long Ridge for H. fulvus) and southern side (Grey Headed for H. fulvus and Watertunnel for A. selago) of the island. Importantly, the western side had unique localities for all species. Interestingly, based on the H. fulvus data, the western populations were relatively young, characterized by high migration rates, small effective (female) population sizes with no isolation-by-distance. The opposite scenario was found for the eastern populations. This spatial genetic structure described for species on Marion Island can be ascribed to both historical events and environmental conditions. These areas with their unique genetic composition are of special conservational concern; consequently this research will contribute to an active management plan for PEI, South Africa’s only Special Nature Reserve. / AFRIKAANSE OPSOMMING: Sub-Antarktiese eilande verteenwoordig die enigste terrestriële bioom in die middel tot hoër breedtegrades van die Suidelike Halfrond. Hierdie eilande besit ‘n verskeidenheid van geologiese oorspronge en geskiedenisse, goed-bewaarde terrestriële ekosisteme en hoë vlakke van endemisme. In ‘n poging om die evolusie en biogeografie van terrestriële taksa in die Suid Pool Area te verstaan, is die eerste grootskaalse molekulêre filogenie saamgestel vir ‘n unieke terrestriële groep, die ameronothoïed miete (genus Halozetes (Oribatida: Ameronothroidea)), vanaf menigte sub-Antarktiese en Maritime Antarktiese lokaliteite. Filogenetiese analises gebaseer op die saamgestelde mitochondriale (sitokroom oksidase subeenheid I (COI)) en nukluêre (histoon-3 (H3)) basispaarvolgordes het aangedui dat die evolusie van hierdie miete habitat spesifiek is (m.a.w inter-gety, supralitoraal en terrestrieël). Ongeag die kritiek teenoor ‘n molekulêre klok, is hierdie miete evolusionêr jonk (<10mjo), wat teenstrydig is met hulle status as ‘n antieke groep wat terugdateer voor Gondwana fragmentasie. Biogeografiese analises het ‘n komplekse patroon aangedui wat grotendeels gekarakteriseer word deur menigte onafhanklike verspreidingsgebeurtenisse bo-oor die Antarktiese Polêre Frontale Zone, wat ooreenstemmend is met vorige bevindinge vir ander mariene en terrestriële taksa. Die molekulêre filogenie het ook aansienlik verskil van die tradisionele taksonomie, dus is taksonomiese aanpassings en herklassifisering van morfologiese karakters noodsaaklik. Sub-Antarktiese Marion Eiland, die groter eiland van die Prins Edward eilandgroep (PEI), het uitermate glasiasie en vulkanisme ondervind. Om die impak van historiese gebeurtenisse (vulkanisme (insluitend onlangse uitbarstings) en glasiasie) en kontemporêre meganismes (geenvloei) op die genetiesgespasieërde verspreiding van spesies vanaf Marion Eiland te bepaal, was twee mietspesies naamlik Eupodes minutus (Prostigmata) en Halozetes fulvus (Oribatida) asook ‘n enkele plantspesie, Azorella selago (Apiaceae), gekies as model organismes. Vir onafhanklike filogeografiese analises, was die mitochondriale basispaarvolgorde (COI) vir beide mietspesies bepaal, terwyl chloroplast basispaarvolgorde (trnH-psbA) asook geamplifiseerde fragmentlengte polimorfisme (AFLP) data gegenereer was vir die kussingplant, A. selago. Aangesien A. selago gekenmerk word deur twee groeivorme, naamlik diskrete kussings en aaneenlopende matte, was dit noodsaaklik om eers die groeidinamika van die plant te ondersoek alvorens ‘n filogeografiese studie kon geskied. Die basispaarvolgordebepalings en fragmentdata het aangedui dat beide mietspesies sowel as die plantspesie betekenisvolle substruktuur vertoon regoor Marion Eiland. Informele vergelykings het unieke populasies aangedui op die westelike (Kaalkoppie vir H. fulvus, La Grange Kop vir E. minutus en Mixed Pickle vir A. selago), oostelike (Bullardstrand vir H. fulvus en Kildalkeybaai vir E. minutus), noordelike (Middelman en Long Ridge vir H. fulvus) en suidelike kant (Grey Headed vir H. fulvus en Watertunnel vir A. selago) van die eiland. Die westelike kant besit dus unieke lokaliteite vir al die spesies. Interressantheidhalwe het die H. fulvus data getoon dat die westelike populasies relatief jonk is en gekarakteriseer word deur hoë migrasiesyfers en klein effektiewe (vroulike) populasiegroottes met geen isolasie-oor-afstand nie. Die resultate vir die populasies aan die oostelike kant van die Marion Eiland was presies teenoorgesteld. Dié beskryfde substruktuur vir die spesies op Marion Eiland is afkomstig van beide historiese gebeurtenisse asook omgewingstoestande. Hierdie areas met hul unieke genetiese samestelling, is belangrik vir natuurbewaring. Hierdie navorsing sal bydra tot die bestuursriglyne van PEI, Suid Afrika se enigste Spesiale Natuurreservaat.

Ácaros tetraniquídeos são considerados pragas secundárias em soja, no entanto, nos últimos anos, foram registrados ataques severos e freqüentes destes em diferentes regiões produtoras do Brasil. Experimentos foram realizados em campo e laboratório com o objetivo de estudar os fatores determinantes dos aumentos populacionais de ácaros tetraniquídeos em soja. Para determinar se cultivares transgênicas de soja seriam mais susceptíveis aos ácaros, foi estudado o ciclo biológico e a tabela de vida dos ácaros Mononychellus planki (McGregor) e Tetranychus urticae Koch em três cultivares de soja transgênicas, glifosato-tolerante, e três não-transgênicas com elevada semelhança genética às respectivas cultivares transgênicas. Testes de toxicidade foram realizados em laboratório com agrotóxicos comumente utilizados em soja para determinar os efeitos destes sobre importantes inimigos naturais dos ácaros tetraniquídeos e das lagartas da soja, os fungos Neozygites floridana e Nomuraea rileyi, respectivamente. Em campo, durante duas safras agrícolas (2007/2008 e 2008/2009), foi estudado o efeito de cinco manejos fitossanitários sobre a flutuação populacional de ácaros tetraniquídeos, lagartas, percevejos fitófagos e de alguns de seus inimigos naturais. As cultivares transgênicas não afetaram significativamente o ciclo biológico de M. planki e T. urticae e as pequenas diferenças observadas para alguns parâmetros da tabela de vida destas espécies entre cultivares não estão relacionadas à modificação genética. A avaliação do efeito dos agrotóxicos sobre os patógenos revelou que o fungicida Alto 100 e o herbicida Roundup Ready inibiram o crescimento micelial de N. rileyi. Para N. floridana todos os fungicidas contendo estrubirulinas inibiram completamente a esporulação, enquanto que os produtos do grupo dos triazóis resultaram em taxas intermediárias de esporulação e germinação de conídios. A espécie M. planki foi mais abundante do que T. urticae em campo. O ácaro predador Neoseiulus anonymus e o fungo N. floridana foram os inimigos naturais associados a estes ácaros pragas. Os fungicidas Priori Xtra e Alto 100 reduziram a prevalência de N. floridana, mas não interferiram na dinâmica de N. anonymus. O inseticida piretróide Decis 25 EC reduziu a densidade deste predador, mas não afetou o fungo. No tratamento onde foram aplicados os fungicidas com o inseticida observou-se aumentos populacionais de ácaros fitófagos. A pulverização do herbicida glifosato não afetou N. anonymus e N. floridana, e a presença de plantas daninhas favoreceu o predador. Os picos populacionais mais elevados de Anticarsia gemmatalis foram observados em 2008/09, nas parcelas onde foram empregados fungicidas, e maiores densidades de Pseudoplusia includens foram observadas no tratamento com Decis 25 EC. A aplicação deste inseticida também afetou negativamente a densidade de insetos predadores e resultou em maiores densidades de percevejos fitófagos. O herbicida glifosato não afetou a densidade de pragas e inimigos naturais, no entanto, a presença de plantas daninhas favoreceu os insetos predadores e desfavoreceu os percevejos fitófagos. Em geral, os estudos em campo indicam que o uso de fungicidas e inseticidas são fatores associados aos aumentos populacionais de ácaros em soja. / Spider mites are secondary pests of soybean, however, recently outbreaks has frequently been reported on different producing regions of Brazil. Experiments were carried out in field and laboratory aiming to determine the main factors associates with spider mite outbreaks in soybean. To determine if genetically modified (GM) soybean varieties are more susceptible to spider mites, the life cycle and life table of the mites Mononychellus planki and Tetranychus urticae was studied on three GM soybean cultivars glyphosate-tolerant and three non-transgenic cultivars genetically similar to the transgenic ones. Toxicological tests were carried out in laboratory with pesticides commonly used in soybean to determine the pesticide effect on important natural enemies of spider mites and soybean catterpillars, the fungi Neozygites floridana and Nomuraea rileyi, respectively. In the field during two growing seasons (2007/2008 and 2008/2009), the effects of five plant protection managements were studied on the population dynamics of spider mites, caterpillars, stink bugs and some of their natural enemies. The transgenic cultivars did not significantly affect the life cycle parameters of M. planki e T. urticae and differences observed for some life table parameters between cultivars are not related to the genetic modification. Evaluation of the effect of pesticides on the pathogens showed that the fungicide Alto 100 and the herbicide Roundup Ready inhibited the mycelial growth of N. rileyi. Against N. floridana, all fungicides with strobilurins completely inhibited sporulation, while the triazole products hence showed intermediate rates of sporulation and conidia germination. The spider mite M. planki was more abundant than T. urticae in the field. The predatory mite Neoseiulus anonymus and the fungus N. floridana were the main natural enemies associated to these mite pests. The fungicides Priori Xtra and Alto 100 reduced the prevalence of N. floridana, though this pesticide did not negatively affected N. anonymus. The pyrethroid insecticide Decis 25 EC reduced the density of this predator, but did not affect the fungus. The treatment where fungicides and the insecticide were applied, increases on populations of phytophagous mites were observed. Spraying of the herbicide glyphosate did not affect N. anonymus and N. floridana, and the presence of weeds favored the predator. Higher population peaks of Anticarsia gemmatalis were associated with fungicide applications in 2008/09 and higher densities of Pseudoplusia includens were observed in treatment with Decis 25 EC. This insecticide also negatively affected the density of predatory insects and resulted on higher densities of stink bugs. The herbicide glyphosate did not affect density of pests and natural enemies; however, the presence of weeds favored insect predators, and resulted on lower populations of stink bugs. Overall, the field studies indicate that the use of fungicides and insecticides are important factors associated to spider mite outbreaks in soybean.

O Sistema de Análise de Perigos e Pontos Críticos de Controle (APPCC) ou Hazard Analysis Critical Control Point (HACCP) é de grande importância para a Saúde Pública, quanto às doenças veiculadas por alimentos. O objetivo deste trabalho foi verificar a aplicabilidade do uso desse sistema na indústria de moagem de trigo, no processamento de farinha de trigo integral, produto com demanda crescente no mercado. Trinta produções de farinha foram coletadas numa indústria cuja capacidade de moagem é de 15ton./h na cidade de São Paulo. A população amostrada foi de 30 sub-amostras de trigo argentino (A) (12,8% de umidade média), 17 sub-amostras de trigo brasileiro (B) (13,1% de umidade média), 30 sub-amostras de trigo preparado para moagem (M) (15,6% de umidade média) e 30 sub-amostras de farinha de trigo integral (FTI), coletadas num período de 5 meses (de outubro de 97 à março de 98). A metodologia utilizada para pesquisa de sujidades leves foi a adotada pelos Métodos Oficiais da AOAC (1995). Houve modificações no método e um estudo foi realizado para conhecer sua performance. No isolamento de fungos foi utilizada a metodologia empregada pela AOAC/FDA Bacteriological Analytical manual (1992). Para identificação de fungos em relação ao gênero foi utilizado o método preconizado GELLI et al.(1990), SAMSON et al (1995), PITT and HOCKING (1997). Na análise de sujidades leves nos trigos foi evidenciada a contaminação por ácaros (A=90%, B=53%, M=77% e FTI=53%); no trigo argentino houve uma predominância para a família Tarsonemidae, enquanto que na respectiva farinha foi a família Acaridae. Alguns ácaros dessa última família estão implicados em reações alérgicas e estão sendo tratados como emergentes na segurança alimentar. Os insetos thisanópteros, os mais freqüentes nos trigos, foram eliminados na farinha de trigo integral. O percentual médio de contaminação fúngica dos grãos foi de A=99%, B=95% e M=94%. O principal gênero encontrado foi Aspergillus spp (A= 79,0%, B= 39,3% e M= 64,2%). O menos freqüente Fusarium spp (A= 2,9%, B= 2,7% e M=1,5%). Na farinha de trigo integral o principal gênero encontrado foi o Penicillium spp e o Fusarium não foi isolado. O desoxinivalenol foi encontrado em uma amostra de farinha de trigo integral a uma concentração de 231 ng/g. O sistema APPCC se aplica aos moinhos e os auxilia a controlar suas produções do ponto de vista da segurança alimentar. / Food safety is a major concern facing the food industry today. Hazard Analysis Critical Control Point (HACCP) provides a structured approach to the assurance of safety of products. The aim of this study was to verify the use of HACCP system in a milling industry, precisely in the whole wheat flour production. At first step two hazards were analyzed: deoxynivalenol and allergenic mites in whole wheat flour Thirty (30) lots of flour were collected in an industry which capacity was 15 ton./h in São Paulo city. Those lots had 30 sub-samples of argentine (A) wheat (12,8% average moisture content), 17 sub-samples of brazilian (B) wheat (13,1% m.c.), 30 sub-samples of wheat for milling (M) (15,6% m.c), and 30 sub-samples of whole wheat flour (FTI) that were analyzed in a five months period (from 97/october to 98/march). Light filth was isolated from grains and flour, according to Official Methods of AOAC International. Methodology of extraction of light filth from whole wheat flour was studied to know the repeatability according to AOAC methods. Fungi isolation was performed according to AOAC/FDA Bacteriological Analytical Manual (1992) methodology; genera were identified according GELLI et al.(1990), SAMSON et al (1995), and PITI and HOCKING (1997). Detection and quantification of deoxynivalenol (DON) were done by thin layer chromatography (TLC) according to SABINO et al. (1989).The most significant light filth contamination in wheat were mites (A= 90%, B= 53%, M= 77% e FTI= 57%), argentine wheat had as a predominant mite the family Tarsonemidae and flour had Acaridae. The average fungal contamination in grains was 99%, 95% e 94% in argentine, brazilian and wheat for milling respectively. The predominant genera was Aspergillus spp ( A= 79,0, B=39,3% e M= 64,2 %), and Fusarium was the least frequent in wheat (A>/b>=2,7%, B= 2,8% e M=1,5%). Only one lot of whole wheat flour was contaminated by DON at level 231 ng/g. This study showed that HACCP system is appropriated for control hazards in milling industry. However, DON should be controlled before wheat get into industry, and this control need to be registered. Mites are new emergentes to cause allergy by ingestion and have to be controlled by GMP procedures.

Ácaros tetraniquídeos são considerados pragas secundárias em soja, no entanto, nos últimos anos, foram registrados ataques severos e freqüentes destes em diferentes regiões produtoras do Brasil. Experimentos foram realizados em campo e laboratório com o objetivo de estudar os fatores determinantes dos aumentos populacionais de ácaros tetraniquídeos em soja. Para determinar se cultivares transgênicas de soja seriam mais susceptíveis aos ácaros, foi estudado o ciclo biológico e a tabela de vida dos ácaros Mononychellus planki (McGregor) e Tetranychus urticae Koch em três cultivares de soja transgênicas, glifosato-tolerante, e três não-transgênicas com elevada semelhança genética às respectivas cultivares transgênicas. Testes de toxicidade foram realizados em laboratório com agrotóxicos comumente utilizados em soja para determinar os efeitos destes sobre importantes inimigos naturais dos ácaros tetraniquídeos e das lagartas da soja, os fungos Neozygites floridana e Nomuraea rileyi, respectivamente. Em campo, durante duas safras agrícolas (2007/2008 e 2008/2009), foi estudado o efeito de cinco manejos fitossanitários sobre a flutuação populacional de ácaros tetraniquídeos, lagartas, percevejos fitófagos e de alguns de seus inimigos naturais. As cultivares transgênicas não afetaram significativamente o ciclo biológico de M. planki e T. urticae e as pequenas diferenças observadas para alguns parâmetros da tabela de vida destas espécies entre cultivares não estão relacionadas à modificação genética. A avaliação do efeito dos agrotóxicos sobre os patógenos revelou que o fungicida Alto 100 e o herbicida Roundup Ready inibiram o crescimento micelial de N. rileyi. Para N. floridana todos os fungicidas contendo estrubirulinas inibiram completamente a esporulação, enquanto que os produtos do grupo dos triazóis resultaram em taxas intermediárias de esporulação e germinação de conídios. A espécie M. planki foi mais abundante do que T. urticae em campo. O ácaro predador Neoseiulus anonymus e o fungo N. floridana foram os inimigos naturais associados a estes ácaros pragas. Os fungicidas Priori Xtra e Alto 100 reduziram a prevalência de N. floridana, mas não interferiram na dinâmica de N. anonymus. O inseticida piretróide Decis 25 EC reduziu a densidade deste predador, mas não afetou o fungo. No tratamento onde foram aplicados os fungicidas com o inseticida observou-se aumentos populacionais de ácaros fitófagos. A pulverização do herbicida glifosato não afetou N. anonymus e N. floridana, e a presença de plantas daninhas favoreceu o predador. Os picos populacionais mais elevados de Anticarsia gemmatalis foram observados em 2008/09, nas parcelas onde foram empregados fungicidas, e maiores densidades de Pseudoplusia includens foram observadas no tratamento com Decis 25 EC. A aplicação deste inseticida também afetou negativamente a densidade de insetos predadores e resultou em maiores densidades de percevejos fitófagos. O herbicida glifosato não afetou a densidade de pragas e inimigos naturais, no entanto, a presença de plantas daninhas favoreceu os insetos predadores e desfavoreceu os percevejos fitófagos. Em geral, os estudos em campo indicam que o uso de fungicidas e inseticidas são fatores associados aos aumentos populacionais de ácaros em soja. / Spider mites are secondary pests of soybean, however, recently outbreaks has frequently been reported on different producing regions of Brazil. Experiments were carried out in field and laboratory aiming to determine the main factors associates with spider mite outbreaks in soybean. To determine if genetically modified (GM) soybean varieties are more susceptible to spider mites, the life cycle and life table of the mites Mononychellus planki and Tetranychus urticae was studied on three GM soybean cultivars glyphosate-tolerant and three non-transgenic cultivars genetically similar to the transgenic ones. Toxicological tests were carried out in laboratory with pesticides commonly used in soybean to determine the pesticide effect on important natural enemies of spider mites and soybean catterpillars, the fungi Neozygites floridana and Nomuraea rileyi, respectively. In the field during two growing seasons (2007/2008 and 2008/2009), the effects of five plant protection managements were studied on the population dynamics of spider mites, caterpillars, stink bugs and some of their natural enemies. The transgenic cultivars did not significantly affect the life cycle parameters of M. planki e T. urticae and differences observed for some life table parameters between cultivars are not related to the genetic modification. Evaluation of the effect of pesticides on the pathogens showed that the fungicide Alto 100 and the herbicide Roundup Ready inhibited the mycelial growth of N. rileyi. Against N. floridana, all fungicides with strobilurins completely inhibited sporulation, while the triazole products hence showed intermediate rates of sporulation and conidia germination. The spider mite M. planki was more abundant than T. urticae in the field. The predatory mite Neoseiulus anonymus and the fungus N. floridana were the main natural enemies associated to these mite pests. The fungicides Priori Xtra and Alto 100 reduced the prevalence of N. floridana, though this pesticide did not negatively affected N. anonymus. The pyrethroid insecticide Decis 25 EC reduced the density of this predator, but did not affect the fungus. The treatment where fungicides and the insecticide were applied, increases on populations of phytophagous mites were observed. Spraying of the herbicide glyphosate did not affect N. anonymus and N. floridana, and the presence of weeds favored the predator. Higher population peaks of Anticarsia gemmatalis were associated with fungicide applications in 2008/09 and higher densities of Pseudoplusia includens were observed in treatment with Decis 25 EC. This insecticide also negatively affected the density of predatory insects and resulted on higher densities of stink bugs. The herbicide glyphosate did not affect density of pests and natural enemies; however, the presence of weeds favored insect predators, and resulted on lower populations of stink bugs. Overall, the field studies indicate that the use of fungicides and insecticides are important factors associated to spider mite outbreaks in soybean.

No description available.

Understanding direct and indirect defense mechanisms that enhance host plant resistance (HPR) and biological control is critical for successful development of an integrated pest management (IPM) approach. Cassava green mite (CGM) (Mononychellus tanajoa Bondar (Acari: Tetranychidae)) is a major arthropod pest of cassava (Manihot esculenta Crantz) in Africa. Strategies to control CGM include HPR and biological control by use of exotic natural enemies particularly the predatory mite Typhlodromalus aripo DeLeon (Acari: Phytoseiidae). The success of the latter depends on continuous survival of the natural enemy which requires suitable host plants and weather conditions. Various plant morphological traits have been recognized as indirect defense mechanisms that enhance HPR to CGM, and/or attract T. aripo in cassava. It was envisaged that integration of HPR and classical biological control approaches through manipulation of such indirect defense traits would lead to a more sustainable management of CGM in view of anticipated climate change. Lack of information on farmers’ perception of CGM and preferred varietal attributes, and gene action controlling the inheritance of CGM resistance also limits success of resistance breeding and adoption of varieties. This research was undertaken to gather information on farmers’ perceptions of cassava varietal attributes and cultural practices in relation to CGM resistance, identify suitable sources of resistance and environments for future breeding; and to determine the nature of gene action controlling CGM resistance and the inheritance of plant morphological traits that enhance the ability of cassava to host and support continuous survival of natural enemies. High fresh storage root yield (FSRY), high storage root dry mass percentage (SRDM%), earliness combined with extended underground storability, and resistance to foliar pests and diseases are the major factors that influence adoption and retention of genotypes by farmers. Moles, termites and CGM are the most widespread and most damaging pests. However, due to the non-conspicuous nature of CGM, its effects are under-estimated and are given limited attention by farmers. The majority of the farmers are familiar with CGM leaf damage symptoms but they cannot associate them with the actual pest. Participation of farmers in field training and field research activities helps them to know CGM. Crop rotation, intercropping, removal of shoot tips, selective pruning of infested shoots, and burning of cassava fields are some of the ways used by farmers to manage CGM. Farmers associate hairy broad-leaved, tall cassava genotypes and pink leaf pigmentation (anthocyanin) with low CGM damage. There is substantial genetic variability in the Zambian cassava germplasm for CGM resistance and associated plant morphological traits such as leaf pubescence (Pbs), leaf retention (LR), stay green (SG), tip size (TS), tip compactness, and plant height (PH), stem diameter (StD), SRDM% and FSRY. Genotypes with wide or specific adaptability for these traits have been identified, and should be recommended for general or localized production and for use as sources of desired genes in crop improvement. Genotypes L9.304/147, 92/000, TME2, 4(2)1425, I60/42 and L9.304/175 combine wide adaptability with high levels of resistance to CGM. Genotypes Kapeza, L9.304/147 and 4(2)1425 are able to produce 13-15 t ha ¯¹ at 9 months after planting suggesting their potential for early bulking. This study has shown that both additive and non-additive gene effects play a role in the expression of CGM resistance and associated plant morphological traits. The best combinations of parents for resistance against CGM were 4(2)1425 x L9.304/147 and Mweru x L9.304/147, while L9.304/147 x I92/000 displayed combined resistance to CGM and cassava mosaic disease (CMD). The resistance of cassava to CGM is positively correlated with Pbs, LR, and TS, SG, PH, StD. Overall, the study has shown that there is wide diversity in the expression of valuable indirect defense traits among genotypes, indicating that there is scope for integration of biological control and host plant resistance for CGM in Zambia. The release of genotypes that exhibit high level of intra-season and inter-season stability for enhanced expression of LR, SG, and Pbs will minimize the impact of CGM on FSRY and SRDM% that results from seasonal effects. Such genotypes should also provide habitat for and thus help to ensure the survival of T. aripo in cassava fields. The study has contributed to the promotion of food security through identification of early-bulking genotypes which also have good potential for extended underground storability of roots. Early-bulking, high FSRY and SRDM% and SRR resistance are farmer-preferred traits. Therefore, enhancement of such traits through plant breeding is likely to increase the adoption of new genotypes by farmers. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Indoor air quality is described as the chemical, physical and biological characteristics of air in a residential or occupational indoor environment. In residential settings, there are many contributions to indoor pollution levels namely; human activities, biological sources and outdoor air. There has been increased focus on house dust due to its potential to contain biological and chemical pollutants in indoor environments. These have the potential to cause harm to human health. The purpose of this study was to conduct toxicological analysis of house dust collected from inside selected Durban residential buildings. The objectives of this study were to isolate, identify and quantify mould occurrence in house dust samples; to measure the occurrence of heavy metals (arsenic, lead and mercury) in house dust; and to analyse the cytotoxicity of house dust on human lung bronchus carcinoma epithelial line (A549) and human lung bronchus virus transformed epithelial cell line (BBM). One hundred and five house dust samples were obtained from households that participated in the South Durban Health Study. In each home, a sample of settled dust was collected, using standardized protocols, then sieved and individually packed into polystyrene bags. The samples were taken from three surface areas namely; living room couches, bed mattresses, and carpets. Well documented methods were used for the isolation, identification and quantification of mould. The samples for heavy metals analysis were sent to Umgeni Water (chemistry laboratory, Pietermaritzburg) where standardised methods were used. Human cell lines were treated with five different dilutions of each house dust extract. Cell viability was assessed using the MTT assay. Toxic effects of house dust extract were analyzed, following house dust extract treatment and cells were stained with double dye (annexin-V- and propidium iodide) and analysed with flow cytometry, and fluorescent microscope. Cytokines were analysed by Microbionix (Neuried, German) using a Luminex®100 plate reader for multiplex human cytokines analysis. There were (n=128) mould types isolated and (n=105) were identified, of which (n=10) were predominately isolated moulds. This was further confirmed by Allerton Provincial Laboratory in Pietermaritzburg. Among the isolated genera in all three surface areas, Rhizopus spp and Penicillium spp were widely distributed throughout surface areas in greater proportion. The overall highest mean which was reported in this study and expressed in colony forming unit per gram (CFU/g) for Penicillium spp ranged (3400 - 62316 CFU/g) obtained from living room couches, followed by Rhizopus spp (5200 - 15990 CFU/g). The mould results were compared with the South African Occupational Health and Safety Act (OHSA) 85 of 1993 as amended suggested guidelines of 1,000, 000 CFU/g. The findings of this study suggest the moulds in the homes studied were below the suggested guideline. However, this does not imply that the indoor conditions are unsafe or hazardous. Instead, the findings act as an indicator of moulds presence indoors. The type of airborne mould, its concentration and extent of exposure and the health status of the occupants of a building will determine the health effects on an individual. Heavy metals were detected in the dust in the following ascending order: arsenic (As) ranged from 1.3 ug/g -18.4 ug/g (mean, 4.26 ug/g), lead (Pb) ranged from 28.0 - 872 ug/g (mean 171.66 ug/g), and mercury (Hg) ranged from 0.6 -19.0 ug/g (mean, 2.22 ug/g). The mean concentration of lead in the dust was within the range of Canadian National Classification guidelines on residential contamination (500 ug/g). There was numerous numbers of samples in this study that exceeded these guidelines. The mean concentration of arsenic was within residential soil guidelines (20 ug/g). Mercury was within limits when compared with Global Hg project guidelines of soil/residential (6.6 ug/g), thought some of samples were notably above this mean. The ability of house dust extract to lower the cell viability which was slightly above 80% (prior treatment) to less than 50% (post treatment) in both cells was observed in this study. The findings in this study showed that dust extract are toxic to human cell lines, and cells undergone a degree of apoptosis and necrosis 62% (A549) and 99% (BBM). The cytokines serve an important role in the non-specific defence external against insults. It was observed that A549 cells up-regulated the release of IL-6 and IL-8 pro-inflammatory cytokines and under-regulated the release of other cytokines analysed (IL-4, IL-13, and TNF-a). BBM cells released IL-4, IL-8 and IL-13 within limit of detection. The presence of moulds in these sampled indoor household dusts, which is comparable with findings elsewhere indoors, show that moulds act as an indicator for building conditions such as dampness, which supports mould growth. Individuals, whether they are sensitized or not, may develop allergic reactions towards spores, thus the elevated numbers of spores quantified in this study are of concern. Some of the heavy metals reported in this study were higher or marginally higher than international norms and guidelines. The findings in this study strongly suggest that house dust extract is toxic to human lung cell lines. It must be noted, however, that this study may not reflect all that happens when a human lung is exposed to house dust. The findings of this study could contribute to the development of South African indoor air guidelines. In conclusion further study needed to be undertaken with respect to air pollution disease such as allergic; the reason being this study shown the reduced expression of cytokines that are involved in allergic inflammation. / Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2009.

The aims of this study were to develop a detailed record of the tetranychid mites of Kenya and Tanzania, to assess the diversity of tetranychid mites in the east African biodiversity hotspots and to determine female characters that can be used to identify the species of the economically important Tetranychus species found in these countries. The genetic diversity of the most abundant Tetranychus species (Tetranychus evansi Baker & Pritchard) was also assessed. The Tetranychidae (Acari) contain some of the most important pest species of phytophagous mites worldwide. Out of the almost 1,300 species in this family, 256 species are known to occur in Africa. Before this study, ten species had been reported from Kenya and only three in Tanzania. The genus Tetranychus to which most of the pest species belongs to, can only be identified to species level by the use of the male aedeagus that is often difficult to visualize. The natural habitat, the Eastern Arc Mountains and East African Coastal Forests in Kenya and Tanzania is recognized as biodiversity hotspots but prior to his study, information on Tetranychidae in these hotspots was lacking. Thus, no information on the natural mite fauna composition was available. In Kenya, 18 tetranychid mite species from various plant hosts have been recorded. Four of these species belong to the subfamily Bryobiinae and the other 14 to the subfamily Tetranychinae. Eight of the mite species identified belong to the genera Bryobia, Petrobia, Peltanobia, Paraplonobia, Duplanychus, Eutetranychus and Mixonychus and are being reported for the first time in Kenya while the other ten had already been reported before. For Tanzania, six species belonging to the genera Tetranychus, Eutetranychus and Mixonychus are being reported for the first time from Tanzania and other three had been reported before. A list of these species, their brief descriptions as well as a key for identification is provided. A redescription of Peltanobia erasmusi including previously undescribed male characters is given. Schizotetranychus kwalensis sp. nov. from Kenya and Brevinychus meshacki from Tanzania were collected on Omorcarpum kirkii (Fabaceae) from Matuga, Kwale district, Kenya and Philonoptera eriocalyx (Fabaceae) from Sangasanga, Mvomero district, Tanzania respectively and described. Revised keys of Brevinychus and of the African species of Schizotetranychus are also provided. Tetranychus evansi Baker & Pritchard ranked highest in abundance amongst all the tetranychid mites collected. It was found in four out of five fragments of the hotspot, and it survives in a wide range of altitudes from as low as 123 m to 1655 m. Molecular examination of T. evansi collected from Kenya and Tanzania and on different host plants revealed an identical DNA sequence of the mitochondrial COI fragment and 19 identical microsatellite alleles suggesting a single introduction of this species to this part of East Africa. Female characters of four Tetranychus species found in Kenya were explored using the scanning electron microscope. Differences in the distances between the duplex setae of species belonging to the desertorum group (Tetranychus evansi Baker & Pritchard and Tetranychus ludeni Zacher) and those grouped by Flechtmann and Knihinicki (2002) under group 9 (Tetranychus neocaledonicus Andre and Tetranychus urticae Koch) were observed. The dorsal striae of T. evansi, T. neocaledonicus and T. urticae have semicircular lobes whereas those on the dorsal striae of T. ludeni are triangular. / Thesis (PhD (Environmental Sciences))--North-West University, Potchefstroom Campus, 2012.