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Lettuce (Lactuca sativa L.) is a member of the family Compositae (Asteraceae). This plant, which is grown for its leaves, is grown in open field and greenhouse conditions almost everywhere in the world and in Turkey. With the present study virus diseases of lettuce and their prevalence in Konya province was revealed for the first time. For this purpose, leaf samples were taken from lettuce plants showing virus diseases symptoms with surveys carried out in Konya province lettuce planting areas from May to August in 2020. Then the collected lettuce leaf samples were tested in laboratory conditions by Double Antibody Sandwich Enzyme-linked Immunosorbent Assay (DAS-ELISA) method to reveal infections of Cucumber mosaic virus (CMV), Miraflori lettuce big vein virus (MiLBVV), Lettuce mosaic virus (LMV), and Tomato spotted wilt virus (TSWV). According to the information obtained from the results of the study, it was determined that 40 out of 97 (41.23%) lettuce plant samples and all (6) weed samples were infected with at least one of the viruses. In lettuce leaf samples; TSWV (27.83%), LMV (12.37%), CMV (10.31%) and MiLBVV (5.15%) infections have been detected. In weed samples; infections of CMV (83.33%), LMV (66.66%), and TSWV (50%) have been revealed. The infections of TSWV, LMV, CMV, and MiLBVV on lettuce plants in Konya province were reported firstly with the study.

Lymphatic-venous malformations (LVMs) are development defects that result in abnormal connections between the lymphatic and venous systems. The authors describe a 7-weeks-old female infant who presented with a right orbital LVM extending to the ipsilateral cheek and subconjunctiva of the right eye, intracranial developmental venous anomalies in the right cerebellum, and a significant right eye intraocular retinal vascular malformation. Since orbital LVM is usually diagnosed in infancy or childhood, pediatric ophthalmologists should actively look for intraocular vascular malformations as such findings can poorly affect a patient’s vision.

RESUMO A alface (Lactuca sativa L.) pertencente à família Asteraceae e é uma das hortaliças mais consumidas no Brasil. O Lettuce mosaic virus (LMV) é um dos vírus mais importantes da cultura e, atualmente, a principal forma de controle é a utilização de genótipos portadores do gene de tolerância mol1 e mo12. Um isolado de LMV proveniente de Botucatu (SP), denominado LMV-Bot, foi identificado quanto as suas características biológicas e moleculares. Ao ser inoculado nas variedades de alface diferenciadoras de patótipos de LMV em alface (‘Ithaca - gene Mo’, ‘Malika - mo11’, ‘Vanguard 75 – Mo e mo12’ e ‘Salinas 88 - mo12’), o LMV-Bot induziu sintomas somente em ‘Salinas 88’. A porção N’ terminal que codifica a proteína capsidial foi amplificada, sequenciada e seu posicionamento filogenético revelou similaridade com dois isolados brasileiros denominados Br6 e A435 e também com um coletado na França (Fr4). Porém, o LMV-Bot não se enquadrou no sub-grupo Most e Common. Os resultados sugerem que apesar de raros, isolados atípicos de LMV são encontrados na natureza infectando alface, e podem contornar o gene de resistência mol2.

The potyvirus Lettuce mosaic virus (LMV) is a common pathogen of lettuce crops worldwide, but it also infects other Asteraceae spp. including ornamentals (2,3,4). Cape daisies (Osteospermum sp.) are widely grown perennial ornamentals reported to be natural hosts of LMV (2,4), which causes faint leaf mosaic and sometimes mild flower breaking. A preliminary observation of mosaic symptoms prompted a large-scale survey during the spring of 2005 in Cape daisies grown in the Tunis metropolitan area and the south of Tunisia (Djerba, Medenine). Two hundred seventy-one samples (Tunis: 14 sites, 219 samples; South: 9 sites, 52 samples) were randomly collected from nurseries, roadway plantings, and home gardens and analyzed. Ninety-three samples (Tunis: 40%, South: 12%; overall: 34%) showed distinct mosaic symptoms. LMV infection was verified by immuno-tissue printing on all collected samples (1), providing evidence for even higher infection levels (Tunis: 60%; South: 25%; overall: 56%). This technique, therefore, allowed the detection of symptomless infection in a significant proportion of samples. It should however, be stressed that symptoms can be very difficult to observe in water-stressed plants, a situation frequently observed in Tunisia. Subsequent PCR analysis with LMV-specific primers (1) of a subset of 24 symptomatic and tissue-print-positive samples confirmed LMV infection in all cases. This is to our knowledge, the first report of LMV infection in Cape daisies in Tunisia. The very high rate of infection observed suggests that these popular ornamentals might constitute a reservoir of LMV as previously reported in the United States (4). References: (1) H. Fakhfakh et al. J. Plant Pathol. 83:3, 2001. (2) R. Jordan and M. Guaragna. (Abstr.) Phytopathology 96(suppl.):S56, 2006. (3) O. Le Gall. No. 399 in: Description of Plant Viruses. A. T. Jones et al., eds. CMI/AAB, Kew, Surrey, UK, 2003. (4) D. C. Opgenorth et al. Plant Dis. 75:751, 1991.

Syfte: Butikskedjornas egna varumärken har utvecklats och förändrats. Studien syftar till att öka förståelse för hur konsumenters inställning till varumärken påverkas av butikskedjornas utveckling av egna märkesvaror och leverantörers märkesvaror, i det tredje steget av köpbeslutsprocessen. Metod: Studien utgår från ett hermeneutiskt perspektiv. En kvalitativ studie med tio semistrukturerade intervjuer har tillämpats för insamling av empiriskt material. Populationen som studerats är tio personer, som ofta handlar på apotek. Medelåldern på respondenterna är 43,8 år. Den teoretiska referensramen är baserad på tidigare forskning inom områdena varumärken och köpbeslutsprocessen. Med grund i det teoretiska ramverket har en intervjuguide framtagits, empirin är således framtagen utifrån intervjuguiden. En tematisk analys har därefter gjorts och redovisas i en empiri- och analysdel. Resultat & slutsats: Respondenterna som handlar på apotek menar att de inte påverkas speciellt mycket av själva varumärket i köpbeslutsprocessen, de gör heller ingen skillnad vid utvärdering mellan egna märkesvaror (EMV) och leverantörers märkesvaror (LMV). Konsumenterna är inte tillräckligt medvetna om vilket varumärke som är EMV eller LMV inom apoteksmarknaden. Vidare har konsumenterna en positiv inställning till EMV och uppfattar att marknaden för dessa varor har växt. Examensarbetets bidrag: Det teoretiska bidraget är att skapa mer förståelse för hur konsumenter påverkas av butikskedjornas egna märkesvaror och leverantörers märkesvaror i det tredje steget av köpbeslutsprocessen. Vår forskning visar att gränserna mellan EMV och LMV håller på att suddas ut, utifrån ett konsumentperspektiv. Förslag till fortsatt forskning: Forskning inom andra branscher än apotek samt andra geografiska platser bör undersökas. Skillnader i konsumentbeteenden mellan könen kan även vara intressant att studera. Aim: The brands of the store chains have evolved and changed. This study aims to increase the understanding of how consumers ' attitudes to brands are influenced by the development of their own branded products and suppliers' branded products, in the third stage of the purchasing decision process. Method: This study is based on a hermeneutic perspective. A qualitative study with ten semi-structured interviews has been applied for the collection of empirical material. The population studied is people who often shop at pharmacies. The mean age of the respondents is 43.8 years. The theoretical frame of reference is based on past research in the areas of brands and the purchasing decision process. Based on the theoretical framework, an interview guide has been developed, thus the empiricism is developed based on the interview guide. A thematic analysis has then been made and reported in an empirical and analytical section. Results & Conclusions: The respondents who shop at pharmacies mean that they are not very much affected by the brand itself in the purchasing decision process, nor do they make any difference when evaluating the store chains ' own branded products and suppliers' branded products. Consumers in the pharmacy market are not sufficiently aware of which brand is the store chains ' own branded products and suppliers' branded products. Furthermore, consumer’s have a positive attitude towards EMV and perceive that the market for these goods has grown. Contribution of the thesis: Our theoretical contribution creates a better understanding of how consumers are affected by the store chains 'own branded products and suppliers' branded products in the third stage of the purchasing decision process. Our research shows that the boundaries between EMV and LMV are being erased from a consumer perspective. Suggestions for future research: Research in industries other than pharmacies and other geographical locations should also be further investigated. It may also be interesting to study gender differences in consumer behaviour.

RESUMO A alface (Lactuca sativa L.) pertencente à família Asteraceae e é uma das hortaliças mais consumidas no Brasil. O Lettuce mosaic virus (LMV) é um dos vírus mais importantes da cultura e, atualmente, a principal forma de controle é a utilização de genótipos portadores do gene de tolerância mol1 e mo12. Um isolado de LMV proveniente de Botucatu (SP), denominado LMV-Bot, foi identificado quanto as suas características biológicas e moleculares. Ao ser inoculado nas variedades de alface diferenciadoras de patótipos de LMV em alface (‘Ithaca - gene Mo’, ‘Malika - mo11’, ‘Vanguard 75 – Mo e mo12’ e ‘Salinas 88 - mo12’), o LMV-Bot induziu sintomas somente em ‘Salinas 88’. A porção N’ terminal que codifica a proteína capsidial foi amplificada, sequenciada e seu posicionamento filogenético revelou similaridade com dois isolados brasileiros denominados Br6 e A435 e também com um coletado na França (Fr4). Porém, o LMV-Bot não se enquadrou no sub-grupo Most e Common. Os resultados sugerem que apesar de raros, isolados atípicos de LMV são encontrados na natureza infectando alface, e podem contornar o gene de resistência mol2.

RESUMO A alface (Lactuca sativa L.) pertencente à família Asteraceae e é uma das hortaliças mais consumidas no Brasil. O Lettuce mosaic virus (LMV) é um dos vírus mais importantes da cultura e, atualmente, a principal forma de controle é a utilização de genótipos portadores do gene de tolerância mol1 e mo12. Um isolado de LMV proveniente de Botucatu (SP), denominado LMV-Bot, foi identificado quanto as suas características biológicas e moleculares. Ao ser inoculado nas variedades de alface diferenciadoras de patótipos de LMV em alface (‘Ithaca - gene Mo’, ‘Malika - mo11’, ‘Vanguard 75 – Mo e mo12’ e ‘Salinas 88 - mo12’), o LMV-Bot induziu sintomas somente em ‘Salinas 88’. A porção N’ terminal que codifica a proteína capsidial foi amplificada, sequenciada e seu posicionamento filogenético revelou similaridade com dois isolados brasileiros denominados Br6 e A435 e também com um coletado na França (Fr4). Porém, o LMV-Bot não se enquadrou no sub-grupo Most e Common. Os resultados sugerem que apesar de raros, isolados atípicos de LMV são encontrados na natureza infectando alface, e podem contornar o gene de resistência mol2. ABSTRACT Lettuce (Lactuca sativa L.) belongs to the Asteraceae family and is one of the most consumed vegetables in Brazil. Lettuce mosaic virus (LMV) an important virus for this crop and, currently, its main control form is based on the utilization of genotypes carrying the tolerance gene mol1 and mol2. A LMV isolate from Botucatu (SP), named LMV-Bot, was identified considering its biological and molecular characteristics. When inoculated in distinctive lettuce varieties that classifies LMV pathotypes (‘Ithaca - Mo gene’, ‘Malika – mol1’ ‘Vanguard 75 - Mo and mol2’ and ‘Salinas 88 - mo12’), LMV-Bot induced symptoms only in ‘Salinas 88’. The N’ terminal coding region for the capsid protein was amplified and sequenced, and its phylogenetic position revealed similarity to two Brazilian isolates named BR6 and A435 and to another one from France (FR4). However, LMV-Bot did not fit in the sub-group Most and Common. Results suggest that, although rare, atypical isolates of LMV are found in nature infecting lettuce and can break the resistance gene mol2.

UMR 1332 BFP - Equipe Virologie; eIF4E plant factor recruitment by the potyvirus particule: Involvement of the VPg covalently linked to the viral RNA. 16. Rencontres de Virologie Végétale (RVV 2017)

RESUMEN: El estudio del consumidor inversionista, proviene de los distintos problemas con los que el pequeño inversor se ha encontrado, sobre todo, en los años de crisis económica que se iniciaron con la contaminación del mercado de la inversión con las hipotecas subprime, y la posterior falta de liquidez en el mercado que hizo que algunas entidades para proteger sus intereses, forzaran la legislación en la materia, provocando que productos que no estaban pensados para el pequeño ahorrador acabaran en su propiedad. También proviene esta necesidad de las formas de inversión alternativa que periódicamente aparecen en el mercado para captar fondos del pequeño ahorrador. El consumidor y el inversor se encuentran con una falta de tipificación cuando actúan realizando labores de inversión. Esta tesis aborda la diferenciación de ambas figuras para poder determinar los derechos, las figuras de protección y las instituciones que les asisten, puesto que la interpretación de las mismas normas diferirá según sea para la protección de un consumidor o de un inversor que carezca de la consideración de inversor, para ello elaboramos una definición que aclare cuándo alguien que invierte es un consumidor, o por el contrario es un inversor. Para lograr este fin abordamos el problema de considerar la inversión como un acto de consumo. También abordamos diferentes problemas prácticos de contratos comercializados en los mercados, en los que los adquirientes piden ser tratados como inversores en vez de consumidores y otros en los que son tratados como inversores y piden que se les reconozca como consumidores, por lo que se abordan los problemas con los que se encuentran en su actuación en los mercados, analizando distintos productos y medios de inversión, y también abordamos la protección que les corresponde, y los límites de estas figuras. De todos estos análisis recogemos los elementos esenciales que posteriormente fundamentarán la definición buscada. Empleamos para ello, el estudio jurisprudencial y doctrinal. Del estudio realizado llegamos a la conclusión de que existe una especialización en los consumidores que actúan invirtiendo, que denominamos consumidores inversionistas.

The viral protein genome-linked (VPg) of potyviruses is a protein covalently linked to the 5′ end of viral RNA. It interacts with eIF4E, a component of the cellular translation initiation complex. It has been suggested that the 5′ RNA-linked VPg could mimic the cellular mRNA cap, promoting synthesis of viral proteins. Here, we report evidence for recruitment of the plant eIF4E by Lettuce mosaic virus (LMV, potyvirus) particles via the 5′ RNA-linked VPg. Analysis of the viral population was performed by enzyme-linked immunosorbent assay–based tests, either with crude extracts of LMV-infected tissues or purified viral particles. In both cases, LMV-VPg and LMV-eIF4E subpopulations could be detected. After reaching a maximum within the first 2 weeks postinoculation, these populations decreased and very few labeled particles were found later than 3 weeks postinoculation. The central domain of VPg (CD-VPg) was found to be exposed at the surface of the particles. Using a purified recombinant lettuce eIF4E and CD-VPg–specific antibodies, we demonstrate that the plant factor binds to the VPg via its central domain. Moreover, the plant eIF4E factor could be imaged at one end of the particles purified from LMV plant extracts, by immunoredox atomic force microscopy coupled to scanning electrochemical microscopy. We discuss the biological significance of these results.

TEZ12162 Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 2017. Kaynakça (s. 59-66) var. XIII, 73 s. :_res. (bzs. rnk.), tablo ;_29 cm. Bu çalışma 2015-2017 yılları sonbahar ve kış dönemlerinde Adana ve Mersin illerinde yaygın olarak marul yetiştiriciliği yapılan alanlarda Marul iri damar hastalığı (Lettuce big-vein disease, LBVD)’nın saptanması ve bu hastalığa neden olan etmen veya etmen kompleksinin belirlenmesi; Marul mozaik virüsü (Lettuce mosaic virus, LMV)’nün tanılanması ve karakterizasyonu amacıyla yürütülmüştür. Arazi çıkışlarında simptomatolojik olarak LBVD (MiLBVV, LBVaV) veya LMV ile enfekteli olduğundan şüphelenilen toplam 160 adet marul bitkisinden örnekleme yapılmış ve ELISA testleri sonucunda, MiLBVV, 53; LMV ise 22 bitkide saptanmıştır. RT-PCR çalışmalarında MiLBVV için MiLBVV(1) ve MiLBVV(2) primer çifti ile Çukurova, Seyhan, Karaisalı, Yakapınar ve Yenice izolatlarından 233 bp; LBVaV’ye özgü VP-248 ve VP-249 primer çifti ile Çukurova, Karaisalı ve Yenice izolatlarından 296 bp; LMV’ye özgü LMV CPR ve LMV CPF primer çifti ile Yakapınar, Yumurtalık ve Yenice’den toplanan marul izolatlarına ait 360 bp büyüklüğünde bandlar elde edilmiştir. Dizi analizleri sonucunda, MiLBVV için, Yenice-1 ve Yenice-2 izolatları aynı grupta yer alırken, Adana’dan alınan izolatlarla Mersin’den alınan izolatlar farklı gruplarda yer almıştır. LBVaV için kullanılan Yüreğir izolatı Suudi Arabistan izolatı ile aynı grupta yer alırken, LMV için kullanılan Yenice-2 izolatı hiçbir ülke izolatı ile aynı grupta yer almamıştır. This study was conducted for detection of and to investigate of causative agents causing Lettuce big-vein disease (LBVD) and diagnosis and characterization of Lettuce mosaic virus (LMV) in the fields where the lettuce cultivation was made extensively in Adana and Mersin provinces in autumn and winter of 2015-2017. A total of 160 lettuce plants suspected to be infected with LBVD (MiLBVV, LBVaV) or LMV were sampled at the field simptomologically. As the result of ELISA tests, MiLBVV and LMV were detected in 53 and 22 plants, respectively. In the RT-PCR studies for MiLBVV, the band a size of 233 bp was obtained by MiLBVV(1)-MiLBVV(2) primer pair for isolates collected from Cukurova, Seyhan, Karaisalı, Yakapınar and Yenice regions; the band a size of 296 bp was obtained for Cukurova, Karaisalı and Yenice isolates by LBVaV specific VP-248 and VP-249 primer pair; a band of 360 bp was observed for isolates collected from Yakapınar, Yumurtalık and Yenice by LMV specific LMV-CPR; LMV-CPF primer pair. As a result of sequence analysis, while Yenice-1 and Yenice-2 isolates of MiLBVV were in the same group, Adana and Mersin isolates of MiLBVV were in different groups. While Yüreğir isolate of LBVaV in the same group with Saudi Arabia isolate, the Yenice-2 isolate used for LMV did not take part any other country isolate. Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi tarafından desteklenmiştir. Proje No: FYL-2016-7227.

Inledning: En distributionskedja fungerar genom att förädla en råvara till färdig produkt genom råvaruleverantörer, producenter, leverantörer, återförsäljare och konsumenter. I den klassiska distributionskedjan är det i regel leverantörerna som hanterar den slutgiltliga förpackningen och står för det varumärke konsumenten ser i butik. Denna marknad har under senare tid upplevt en stor förändring i form av återförsäljarnas egna märkesvaror (EMV). Dessa varor är tillverkade för att vara så lika marknadsledaren som möjligt och står ofta dessutom direkt bredvid dem i butikshyllan. I regel kostar de lite mindre men upplevs ha liknande värde och kvalitet. Marknadsandelarna för dessa egna märkesvaror har de senaste åren ökat stort och förväntas öka ännu mer. Återförsäljarna tillverkar inte dessa egna märkesvaror själva - de produceras av leverantörerna. Då denna marknad är mättad förlorar leverantörerna marknadsandelar då dessa produkter tar plats på marknaden. Denna studie vill gå till botten med hur leverantörerna hanterar denna trend för att fortsätta vara lönsamma och vara en del av distributionskedjan. Syfte: Studien syftar till att utforska leverantörers möjligheter, risker och strategiska beslut i hänseende till en organisations plats och styrka i distributionskedjan. Metod: Detta är en kvalitativ studie som utgår från leverantörens perspektiv. Empirin har samlats in genom semistrukturerade intervjuer med nyckelpersoner hos leverantörsorganisationer som är engagerade i EMV-produktion. Slutsats: EMV erbjuder leverantörerna många möjligheter till tillväxt och utökad konkurrensstyrka, men till en sämre marginal och kostnadsstruktur vilket kan ha förödande konsekvenser. EMV utmanar den klassiska synen på distributionskedjan och konkurrensstrategier. Introduction: A classic distribution chain consists of a raw material supplier, manufacturer, wholesaler, retailer and consumer. In this chain it's usually the manufacturers that delivers the branded product which ends up in the store shelf. This market has in recent times had a great change in the form of the retailers own brands (PL). These products are made to be similar to the market leader, and they are often placed right next to them on the store shelf. As a rule they have a slightly lower price but the similar quality. These products have risen in popularity and they are expected to rise even more. The retailers however do not manufacture their own products - that is the manufacturer's job. Considering the market is completely mature, this implicates that whenever a new product enters, it does this on the cost of someone else. This study wants to examine how the manufacturers work to keep their place in the distribution chain. Purpose: The purpose of this study is to explore the manufacturer's opportunities, risks and strategic possibilities regarding their place in the distribution chain. Methodology: This is a qualitative study from the suppliers perspective. The data is collected through semi-structured interviews with key personalities from within the organizations who are engaged with private label production. Conclusions: EMV offer the manufacturers many possibilities for growth and strength, but at the cost of lower margins. PL challenges the classic view of the distribution chain and strategies of competition.

O objetivo deste trabalho foi selecionar famílias F4 de alface, oriundas do cruzamento entre as cultivares Verônica e Salinas 88, para o cultivo no verão, com relação ao tipo de folha, e à resistência ao Lettuce mosaic virus (LMV) e ao nematóide-das-galhas Meloidogyne javanica. Primeiramente, avaliaram-se a coloração da folha, tipos de borda e limbo foliares, além da tolerância ao calor no campo, em blocos ao acaso compostos pelas 15 famílias F4 previamente selecionadas, pelas cultivares parentais e pela cultivar testemunha Regina 71 (folhas lisas e tolerante ao calor), com cinco repetições e oito plantas por parcela. Na segunda etapa, as famílias foram avaliadas quanto à resistência ao LMV e ao nematóide-das-galhas, em bandejas de 128 células acondicionadas em estufa. As médias das notas atribuídas a cada família foram comparadas às médias de cada cultivar parental pelo teste de Dunnet (5%). A família AFX007B-140-21, homozigota resistente aos nematóides e ao LMV e, também, tolerante ao calor, foi a mais promissora. O cruzamento entre uma cultivar de folhas crespas e soltas com uma de folhas crespas e repolhuda, pode originar linhagens promissoras tanto de folhas crespas quanto de folhas lisas. The aim of this work was to select F4 lettuce families, derived from the cross 'Veronica' x 'Salinas 88 ', for summer cropping, type of leaves, and for resistance to Meloidogyne javanica and to Lettuce mosaic virus (LMV). First, evaluations were made for leaf colour, leaf limb, border type, and heat tolerance in the field, in a complete blocks desing, in 15 F4 families previously selected, parent cultivars and, as control, the cultivar Regina 71 (butterleaf and tolerant to heat). Five replicates and eight plants per plot were used. As second step, the families were evaluated in greenhouse, in 128-cell expanded polystyrene trays, for resistance to LMV and root-knot nematodes. Score means of each family were compared to the means of each parental cultivar by Dunnett test at 5% probability. Family AFX007B-140-21, homozygous for root-knot nematodes, for LMV and heat tolerant, was the most promising. The cross between crisp and butter leaf cultivars can originate promising lineages both with crisp and butter leaves.

Two Lettuce mosaic virus isolates capable of overcoming the resistance afforded by the resistance gene mo12 in lettuce, LMV-AF199 from Brazil, and LMV-E, an European isolate, were evaluated for the rapidity and severity of symptoms induced on the lettuce variety Salinas 88 (mo12). The mosaic symptoms on Salinas 88 plants inoculated with LMV-AF199 appeared 7 days post-inoculation (dpi) and 15 dpi for LMV-E. The symptoms induced by LMV-AF199 in this cultivar were also more severe than those induced by LMV-E. In order to identify the region of the viral genome responsible for this phenotype, recombinant viruses were constructed between these isolates and the phenotype of each recombinant was analysed. The region encoding proteins P1 and HcPro from LMV-AF199 was associated with the increased virulence in Salinas 88., Dois isolados de Lettuce mosaic virus capazes de contornar a resistência conferida pelo gene mo12 em alface, LMV-AF199 proveniente do Brasil e LMV-E um isolado europeu, foram avaliados quanto à rapidez e à severidade dos sintomas induzidos em alface variedade Salinas 88 (mo12). Os sintomas de mosaico induzidos pelo isolado LMV-AF-199 em Salinas 88 são mais severos e aparecem aos 7 dias após a inoculação (dpi), enquanto que para o isolado LMV-E os sintomas são visíveis somente a partir dos 15 dpi. Com o intuito de identificar a região do genoma viral responsável por este fenótipo, vírus recombinantes foram construídos entre estes dois isolados, e o fenótipo avaliado quanto a rapidez e severidade dos sintomas em Salinas-88. A região codificadora para as proteínas P1 e Hc-Pro do LMV-AF199 foi associada com o aumento da virulência deste isolado em Salinas-88.

Using recombinant proteins produced in bacteria or in infected plants, interactions between the VPg and HcPro of Lettuce mosaic potyvirus (LMV) and between LMV VPg and the lettuce translation initiation factor 4E, the cap-binding protein (eIF4E), were demonstrated in vitro. Interaction with eIF4E and HcPro both involved the same VPg central domain. The structure of this domain in the VPg context was predicted to include an amphiphilic α-helix, with the amino acids related to biological functions in various potyviruses exposed at the hydrophilic side.

LMV is one of the most important pathogens of lettuce worldwide. Based on their ability to overcome the resistance genes mo1¹ and mo1² in lettuce, isolates can be divided in two types: LMV-Most, which can infect and are seed-borne in cultivars containing the mo1 gene and LMV-Common, which do not cause symptoms on these cultivars and are seed transmitted only in susceptible cultivars. To evaluate the occurrence of these two types of LMV isolates, a survey was carried out during 2002-2005 in three lettuce production areas from São Paulo State. Total RNA was used for the diagnosis of LMV isolates by RT-PCR using universal primers for the variable N-terminus of the capsid protein, in the 3' end of the genome. Positives samples were analyzed by a second RT-PCR using specifics primers for LMV-Most isolates designed to amplify a fragment from the central region (CI-VPg) of the genome. A total of 1362 samples showing mosaic symptoms were collected and 504 (37.29 %) were positives for LMV. On susceptible lettuce cultivars, LMV-Common was prevalent (77.3%). LMV-Most was found frequently associated with tolerant (mo1¹) lettuce cultivars. Susceptible cultivars correspond today for most of the area of lettuce production. So, despite the ability of LMV-Most isolates to overcome the resistance provided by the recessive mo1¹ gene, they are not prevalent in the conditions of São Paulo State.O LMV ocorre em todo o mundo e é considerado um dos patógenos mais importantes para a cultura da alface. De acordo com a habilidade em contornar os genes de resistência mo1¹ e mo1² encontrados em alface, os isolados de LMV podem ser dividos em dois sub-grupos: LMV-Most, capazes de contornar a resistência propiciada por estes genes e de serem transmitidos pela semente nestas cutivares, e LMV-Common, que não são capazes de causar sintomas nestes cultivares, além de serem transmitidos pela semente somente em cultivares suscetíveis. Para avaliar a ocorrência destes dois tipos de isolados de LMV foram coletadas, durante 2002-2005, amostras de alface com sintomas de mosaico em áreas de produção de alface comercial das regiões de Campinas, Mogi das Cruzes e Bauru no estado de São Paulo. O RNA total foi utilizado para detecção por RT-PCR utilizando-se oligonucleotídeos universais para LMV que amplificam a porção N-terminal variável da capa protéica, localizada no terminal 3´do genoma. As amostras positivas foram analisadas por um segundo primer que amplifica um fragmento da região central (CI-VPg) do genoma viral. Um total de 1362 amostras foram avaliadas, tendo sido detectado o LMV em 504 amostras (37,29%). O LMV-Common prevaleceu em variedades suscetíveis (77,3%). O LMV-Most foi encontrado frequentemente associado a variedades portadoras do gene de tolerância mo1¹. Apesar da existência dos LMV-Most capazes de contornar a resistência em alface, estes não predominam em nossa condições.

National audience

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:41Z No. of bitstreams: 1 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) Made available in DSpace on 2013-08-22T18:49:41Z (GMT). No. of bitstreams: 1 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) Previous issue date: 2012-09-01 Made available in DSpace on 2013-09-30T17:45:54Z (GMT). No. of bitstreams: 2 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) S0100-54052012000300012.pdf.txt: 11779 bytes, checksum: f7b89a6efb2acb16c03e3af5bb5165e2 (MD5) Previous issue date: 2012-09-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:20:27Z No. of bitstreams: 2 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) S0100-54052012000300012.pdf.txt: 11779 bytes, checksum: f7b89a6efb2acb16c03e3af5bb5165e2 (MD5) Made available in DSpace on 2014-05-20T13:20:27Z (GMT). No. of bitstreams: 2 S0100-54052012000300012.pdf: 246542 bytes, checksum: e921c8ee93e61edd8659bb2a00f82a9a (MD5) S0100-54052012000300012.pdf.txt: 11779 bytes, checksum: f7b89a6efb2acb16c03e3af5bb5165e2 (MD5) Previous issue date: 2012-09-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Entre os problemas fitossanitários da cultura da alface estão as doenças causadas por vírus. Três vírus causam sintomas de mosaico praticamente indistinguíveis: o Lettuce mosaic virus (LMV, Potyvirus), o Lettuce mottle virus (LeMoV, Sequivirus) e o Bidens mosaic virus (BiMV, Potyvirus). Através de RT-PCR utilizando-se oligonucleotídeos específicos para cada um destes vírus, amostras de alface e plantas invasoras, preferencialmente com sintoma de mosaico, foram coletadas em campos de produção de alface das regiões de Mogi das Cruzes, Campinas e Bauru no Estado de São Paulo e analisadas para a presença dos vírus. Verificou-se que o LeMoV foi o vírus encontrado com maior freqüência, seguido do LMV. A ocorrência de BiMV em alface foi extremamente baixa e restrita às regiões de Campinas e Bauru, onde também foi verificado em plantas invasoras como Bidens pilosa e Galinsoga parviflora. Esta ultima é hospedeira dos três vírus. Among the phytosanitary problems affecting lettuce culture are the diseases caused by viruses. Three viruses cause almost indistinguishable mosaic symptoms: Lettuce mosaic virus (LMV, Potyvirus), Lettuce mottle virus (LeMoV, Sequivirus) and Bidens mosaic virus (BiMV, Potyvirus). By RT-PCR using specific primers for each virus, lettuce and weed samples, preferably with mosaic symptoms, and collected from lettuce fields in the regions of Mogi das Cruzes, Campinas and Bauru, São Paulo State, Brazil, were analyzed for the presence of these viruses. LeMoV was the most frequently found virus, followed by LMV. The occurrence of BiMV in lettuce was extremely low and restricted to the regions of Campinas and Bauru, where it was also found in weeds such as Bidens pilosa and Galinsoga parviflora. The latter plant is the host of these three viruses. UNESP Faculdade de Ciências Agronômicas Departamento de Produção Vegetal Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) Recursos Genéticos e Biotecnologia UNESP Faculdade de Ciências Agronômicas Departamento de Produção Vegetal

8 páginas, 6 fig. y 1 tabla, Aphid-transmitted viruses frequently cause severe epidemics in lettuce grown under Mediterranean climates. Spatio-temporal dynamics of aphid-transmitted viruses and its vector were studied on lettuce (Lactuca sativa L.) grown under tunnels covered by two types of nets: a commercial UV-absorbing net (Bionet) and a Standard net. A group of plants infected by Cucumber mosaic virus (CMV, family Bromoviridae, genus Cucumovirus) and Lettuce mosaic virus (LMV, family Potyviridae, genus Potyvirus) was transplanted in each plot. The same virus-infected source plants were artificially infested by the aphid Macrosiphum euphorbiae (Thomas). Secondary spread of insects was weekly monitored and plants were sampled for the detection of viruses every two weeks. In 2008, the infection rate of both CMV and LMV were lower under the Bionet than under the Standard cover, probably due to the lower population density and lower dispersal rate achieved by M. euphorbiae. However, during spring of 2009, significant differences in the rate of infection between the two covers were only found for LMV six weeks after transplant. The spatial distribution of the viruses analysed by SADIE methodology was “at random”, and it was not associated to the spatial pattern of the vector. The results obtained are discussed analyzing the wide range of interactions that occurred among UV-radiation, host plant, viruses, insect vector and environmental conditions. Our results show that UV-absorbing nets can be recommended as a component of an integrated disease management program to reduce secondary spread of lettuce viruses, although not as a control measure on its own., Weare indebted to Pedro Hernaiz for conduct field experiments, Miguel Angel Mora for the excellent technical assistance in virus assessment, and Joaquín Campos for measuring the transmission properties of the nets. We thank the Spanish Ministry of Science and Innovation (PET2006 0021; AGL2007-66399-C03-01/02) and the CSIC for the fellowship I3P-BPD-2006 to Saioa Legarrea.

National audience

In recent years, the factors of the eukaryotic translation initiation complex were identified as essential determinants of plant susceptibility to RNA viruses, including potyviruses, the largest and economically the most important of the plant virus groups. Members of this group are responsible for important virus diseases affecting all types of vegetable, fruit, and field crops.In particular, the recessive alleles mo11 and mo12 of mo1 gene, which previously identified as encoding for the translation initiation factor eIF4E, are currently used to protect lettuce crops against lettuce mosaic potyvirus (LMV).Based on the results obtained in the laboratory showing that the LMV determinants involved in the mo1 resistance overcoming include not only the area encoding for the VPg but also upstream, the C-terminal region of that encoding for the CI, my work of thesis consisted in (1) confirm that LMV encodes for two virulence factors, CI and VPg (2) identified by site-directed and random mutagenesis a key amino acids of the CI protein involved in eIF4E-mediated resistance overcoming (3) initiate a functional characterization of interactions involving the three partners eIF4E, VPg and CI.The results obtained showed that the exchange of VPg of a virulent isolate (LMV-E) in a non-virulent (LMV-0) is sufficient to restore full compatibility with lettuce cultivars carrying mo11 allele, but not mo12, whereas the region encoding for the C-terminal portion of the CI and 6K2, is sufficient to overcoming both mo1 alleles. The point mutation in the CI (LMV-0-S621T) obtained by site-directed mutagenesis is able to overcome the resistance conferred by mo12 and partly that conferred by mo11 while the reciprocal mutation (LMV-E-T621S) loses its ability to overcome both resistance alleles.So this is the first example of a potyvirus CI gene acting as a virulence determinant in overcoming eIF4E-mediated resistance. Indeed, the potyvirus VPg was previously identified as the sole virulence determinant vis-a-vis eIF4E. It seems that LMV can use two viral factors (CI and VPg) to overcome the mo1 resistance alleles.This property, combined with the fact that LMV isolates from the wild or ornamental origin are able to evolve towards the overcoming could therefore pose a risk to the durability of the mo1 resistance. Preliminary works were carried on during this thesis to better understand the exact role of mutations affecting virulence factors in the evolutionary process of adaptation of LMV to the pressures imposed by mo1 alleles.Finally, the involvement of the LMV CI in mo1 resistance breaking suggests that this protein could also interact (such as VPg), directly or indirectly with eIF4E. We have shown for the first time in vitro and in vivo interactions between the C-terminal region of the CI protein and the lettuce eIF4E protein. In addition, the mutation at position 621 of the CI which has a key role in mo1 resistance overcoming does not seem to affect these interactions in vitro., Ces dernières années, les facteurs du complexe d'initiation de la traduction eucaryote ont été identifiés comme des déterminants essentiels dans la sensibilité des plantes aux virus à ARN, y compris les potyvirus, genre le plus important à la fois de par leur nombre et leur importance économique chez des espèces légumières, fruitières et de grandes cultures.En particulier, les allèles récessifs mo11 et mo12 du gène mo1 précédemment identifié comme codant pour le facteur d'initiation de la traduction eIF4E, sont actuellement utilisés pour protéger les cultures de laitue contre le potyvirus de la mosaïque de la laitue (LMV).Partant des résultats obtenus au laboratoire démontrant que les déterminants du LMV impliqués dans le contournement de la résistance mo1 comprennent non seulement le domaine codant pour la VPg mais aussi, en amont, l’extrémité carboxy-terminale de celui codant pour la CI, mon travail de thèse a consisté à (1) confirmer que le LMV code pour deux facteurs de virulence, la CI et la VPg (2) identifier par mutagenèse dirigée et aléatoire des acides aminés clés de la CI impliqués dans le contournement de la résistance contrôlée par eIF4E (3) entamer une caractérisation fonctionnelle des interactions impliquant les trois partenaires eIF4E, CI et VPg.Les résultats obtenus ont montré que l'échange de la VPg d'un isolat virulent (LMV-E) dans un non virulent (LMV-0) est suffisant pour restituer la compatibilité complète avec les variétés de laitue portant l'allèle mo11, mais pas mo12, alors que la région codant pour la portion C-terminale de la CI et la 6K2, suffit pour contourner les deux allèles de mo1. Le mutant ponctuel dans la CI (LMV-0-S621T) obtenu par mutagenèse dirigée est capable de contourner la résistance conférée par mo12 et partiellement celle conférée par mo11 tandis que le mutant réciproque (LMV-E-T621S) perd sa capacité à contourner les deux allèles de résistance. Il s’agit donc là du premier exemple d'un gène de CI de potyvirus, agissant comme un déterminant de contournement de la résistance récessive contrôlée par eIF4E. En effet, la VPg des potyvirus a été identifiée jusque là comme l’unique facteur de virulence vis-à-vis de eIF4E. Il semble donc que le LMV puisse utiliser deux facteurs viraux (CI et VPg) pour le contournement des allèles de résistance mo1.Cette propriété, associée au fait que des isolats de LMV d’origine sauvage ou ornementale soient capables d’évoluer vers le contournement pourraient donc présenter un risque pour la durabilité des résistances mo1. Des travaux préliminaires ont été menés lors de cette thèse afin de mieux comprendre le rôle exact des mutations des facteurs de virulence dans le processus évolutif d’adaptation du LMV aux pressions imposées par les allèles mo1.Enfin, l’implication de la CI dans le contournement de la résistance mo1 laisse supposer que cette protéine pourrait elle aussi interagir (comme la VPg), directement ou non, avec eIF4E. Nous avons montré pour la première fois in vitro et in vivo l’interaction entre la région C-terminale de la CI et la protéine eIF4E de laitue. De plus, la mutation en position 621 de la CI ayant un rôle clé dans le contournement de la résistance mo1 ne semble pas affecter ces interactions in vitro

Recently, retailers within the Swedish grocery retail sector have launched lines of products under its own brand, quite often produced by manufactures within the same category of products. The common term of this phenomenon is called private labels. Therefore, private labels could be seen as competitors against branded goods, despite the fact that it is, in several cases, the same manufacturer who produces each of the products. The main purpose of this study is to provide understanding of how the manufacturers choose to position themselves, formulate their strategies and compete on the market among private labels, also to examine the motive behind the manufacturer's choice to produce private labels. The study intends to provide a broader view of how the interaction between manufacturers, retailers, private labels and branded goods appears on the Swedish market. We decided to use a qualitative research method and personal interviews to approach the study. After having identified the manufacturers that produces private labels, five semi-structured interviews were held with key people representing each manufacturer. The survey showed that manufacturers are largely interested in the production of private label. It has mainly to do with the excess capacity in the manufacturer’s factories. The retailer’s procurement methods in negotiations have led the manufacturers to produce private labels at the limit of what is profitable. The investigation concluded that the producers must be innovative marketers to meet the competition of private labels.

Diplôme : Dr. d'Université

A study was conducted to evaluate current proposed models for assessing Medicago sativa L. hay quality, using near infrared reflectance spectroscopy (NIRS) analyses and Cornell Nett Carbohydrate and Protein System (CNCPS) milk production prediction as a criterion of accuracy. Application of the theoretically-based summative total digestible nutrients (TDNlig) model of Weiss et al. (1992), using lignin to determine truly digestible NDF, explained almost all of the variation in milk yield (MY) (r² = 0.98). However, this model involves high analysis costs to develop and maintain NIRS calibrations and several of its components were poorly predicted by NIRS and therefore, not suited for quality assessment in practice. Current available models (forage quality index (FQI), relative forage quality (RFQ); relative feed value (RFV)) for assessing Medicago sativa L. hay quality revealed lower accuracies (r² = 0.83, r² = 0.76, r² = 0.61, respectively), especially when protein was included in the model (total forage quality index (TFI); r² < 0.49). The developed empirical equation named lucerne milk value (LMV), including ADF, ash and lignin (Y = b0 – b1ADF – b2ash – b3lignin) (r² = 0.96), proved to be the most practical, simplistic, economical and accurate quality evaluation model for commercial application.

Background VPgs are viral proteins linked to the 5' end of some viral genomes. Interactions between several VPgs and eukaryotic translation initiation factors eIF4Es are critical for plant infection. However, VPgs are not restricted to phytoviruses, being also involved in genome replication and protein translation of several animal viruses. To date, structural data are still limited to small picornaviral VPgs. Recently three phytoviral VPgs were shown to be natively unfolded proteins. Results In this paper, we report the bacterial expression, purification and biochemical characterization of two phytoviral VPgs, namely the VPgs of Rice yellow mottle virus (RYMV, genus Sobemovirus) and Lettuce mosaic virus (LMV, genus Potyvirus). Using far-UV circular dichroism and size exclusion chromatography, we show that RYMV and LMV VPgs are predominantly or partly unstructured in solution, respectively. Using several disorder predictors, we show that both proteins are predicted to possess disordered regions. We next extend theses results to 14 VPgs representative of the viral diversity. Disordered regions were predicted in all VPg sequences whatever the genus and the family. Conclusion Based on these results, we propose that intrinsic disorder is a common feature of VPgs. The functional role of intrinsic disorder is discussed in light of the biological roles of VPgs.

LMV is one of the most important pathogens of lettuce worldwide. Based on their ability to overcome the resistance genes mo1¹ and mo1² in lettuce, isolates can be divided in two types: LMV-Most, which can infect and are seed-borne in cultivars containing the mo1 gene and LMV-Common, which do not cause symptoms on these cultivars and are seed transmitted only in susceptible cultivars. To evaluate the occurrence of these two types of LMV isolates, a survey was carried out during 2002-2005 in three lettuce production areas from São Paulo State. Total RNA was used for the diagnosis of LMV isolates by RT-PCR using universal primers for the variable N-terminus of the capsid protein, in the 3' end of the genome. Positives samples were analyzed by a second RT-PCR using specifics primers for LMV-Most isolates designed to amplify a fragment from the central region (CI-VPg) of the genome. A total of 1362 samples showing mosaic symptoms were collected and 504 (37.29 %) were positives for LMV. On susceptible lettuce cultivars, LMV-Common was prevalent (77.3%). LMV-Most was found frequently associated with tolerant (mo1¹) lettuce cultivars. Susceptible cultivars correspond today for most of the area of lettuce production. So, despite the ability of LMV-Most isolates to overcome the resistance provided by the recessive mo1¹ gene, they are not prevalent in the conditions of São Paulo State. O LMV ocorre em todo o mundo e é considerado um dos patógenos mais importantes para a cultura da alface. De acordo com a habilidade em contornar os genes de resistência mo1¹ e mo1² encontrados em alface, os isolados de LMV podem ser dividos em dois sub-grupos: LMV-Most, capazes de contornar a resistência propiciada por estes genes e de serem transmitidos pela semente nestas cutivares, e LMV-Common, que não são capazes de causar sintomas nestes cultivares, além de serem transmitidos pela semente somente em cultivares suscetíveis. Para avaliar a ocorrência destes dois tipos de isolados de LMV foram coletadas, durante 2002-2005, amostras de alface com sintomas de mosaico em áreas de produção de alface comercial das regiões de Campinas, Mogi das Cruzes e Bauru no estado de São Paulo. O RNA total foi utilizado para detecção por RT-PCR utilizando-se oligonucleotídeos universais para LMV que amplificam a porção N-terminal variável da capa protéica, localizada no terminal 3´do genoma. As amostras positivas foram analisadas por um segundo primer que amplifica um fragmento da região central (CI-VPg) do genoma viral. Um total de 1362 amostras foram avaliadas, tendo sido detectado o LMV em 504 amostras (37,29%). O LMV-Common prevaleceu em variedades suscetíveis (77,3%). O LMV-Most foi encontrado frequentemente associado a variedades portadoras do gene de tolerância mo1¹. Apesar da existência dos LMV-Most capazes de contornar a resistência em alface, estes não predominam em nossa condições.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:49:31Z No. of bitstreams: 1 S0100-54052008000200009.pdf: 123994 bytes, checksum: 4e5a0145e037c43b4605377f51f5dd01 (MD5) Made available in DSpace on 2013-08-22T18:49:31Z (GMT). No. of bitstreams: 1 S0100-54052008000200009.pdf: 123994 bytes, checksum: 4e5a0145e037c43b4605377f51f5dd01 (MD5) Previous issue date: 2008-06-01 Made available in DSpace on 2013-09-30T17:46:58Z (GMT). No. of bitstreams: 2 S0100-54052008000200009.pdf: 123994 bytes, checksum: 4e5a0145e037c43b4605377f51f5dd01 (MD5) S0100-54052008000200009.pdf.txt: 12482 bytes, checksum: a57e7b8c28318d6b7fa01614ada865f1 (MD5) Previous issue date: 2008-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:20:48Z No. of bitstreams: 2 S0100-54052008000200009.pdf: 123994 bytes, checksum: 4e5a0145e037c43b4605377f51f5dd01 (MD5) S0100-54052008000200009.pdf.txt: 12482 bytes, checksum: a57e7b8c28318d6b7fa01614ada865f1 (MD5) Made available in DSpace on 2014-05-20T13:20:48Z (GMT). No. of bitstreams: 2 S0100-54052008000200009.pdf: 123994 bytes, checksum: 4e5a0145e037c43b4605377f51f5dd01 (MD5) S0100-54052008000200009.pdf.txt: 12482 bytes, checksum: a57e7b8c28318d6b7fa01614ada865f1 (MD5) Previous issue date: 2008-06-01 O LMV ocorre em todo o mundo e é considerado um dos patógenos mais importantes para a cultura da alface. de acordo com a habilidade em contornar os genes de resistência mo1¹ e mo1² encontrados em alface, os isolados de LMV podem ser dividos em dois sub-grupos: LMV-Most, capazes de contornar a resistência propiciada por estes genes e de serem transmitidos pela semente nestas cutivares, e LMV-Common, que não são capazes de causar sintomas nestes cultivares, além de serem transmitidos pela semente somente em cultivares suscetíveis. Para avaliar a ocorrência destes dois tipos de isolados de LMV foram coletadas, durante 2002-2005, amostras de alface com sintomas de mosaico em áreas de produção de alface comercial das regiões de Campinas, Mogi das Cruzes e Bauru no estado de São Paulo. O RNA total foi utilizado para detecção por RT-PCR utilizando-se oligonucleotídeos universais para LMV que amplificam a porção N-terminal variável da capa protéica, localizada no terminal 3´do genoma. As amostras positivas foram analisadas por um segundo primer que amplifica um fragmento da região central (CI-VPg) do genoma viral. Um total de 1362 amostras foram avaliadas, tendo sido detectado o LMV em 504 amostras (37,29%). O LMV-Common prevaleceu em variedades suscetíveis (77,3%). O LMV-Most foi encontrado frequentemente associado a variedades portadoras do gene de tolerância mo1¹. Apesar da existência dos LMV-Most capazes de contornar a resistência em alface, estes não predominam em nossa condições. LMV is one of the most important pathogens of lettuce worldwide. Based on their ability to overcome the resistance genes mo1¹ and mo1² in lettuce, isolates can be divided in two types: LMV-Most, which can infect and are seed-borne in cultivars containing the mo1 gene and LMV-Common, which do not cause symptoms on these cultivars and are seed transmitted only in susceptible cultivars. To evaluate the occurrence of these two types of LMV isolates, a survey was carried out during 2002-2005 in three lettuce production areas from São Paulo State. Total RNA was used for the diagnosis of LMV isolates by RT-PCR using universal primers for the variable N-terminus of the capsid protein, in the 3' end of the genome. Positives samples were analyzed by a second RT-PCR using specifics primers for LMV-Most isolates designed to amplify a fragment from the central region (CI-VPg) of the genome. A total of 1362 samples showing mosaic symptoms were collected and 504 (37.29 %) were positives for LMV. on susceptible lettuce cultivars, LMV-Common was prevalent (77.3%). LMV-Most was found frequently associated with tolerant (mo1¹) lettuce cultivars. Susceptible cultivars correspond today for most of the area of lettuce production. So, despite the ability of LMV-Most isolates to overcome the resistance provided by the recessive mo1¹ gene, they are not prevalent in the conditions of São Paulo State. Universidade Estadual Paulista Faculdade de Ciências Agronômicas Depto. de Produção Vegetal/Defesa Fitossanitária Tomatec, Agro comercial Ltda Sindicato Rural de Mogi das Cruzes Universidade Estadual Paulista Faculdade de Ciências Agronômicas Depto. de Produção Vegetal/Defesa Fitossanitária

SUMMARY Taxonomy: Lettuce mosaic virus (LMV) belongs to the genus Potyvirus (type species Potato virus Y) in the family Potyviridae. Physical properties: The virion is filamentous, flexuous with a length of 750 nm and a width of 15 nm. The particles are made of a genomic RNA of 10 080 nucleotides, covalently linked to a viral-encoded protein (the VPg) at the 5′ end and with a 3′ poly A tail, and encapsidated in a single type of capsid protein. The molecular weight of the capsid protein subunit has been estimated electrophoretically to be 34 kDa and estimated from the amino acid sequence to be 31 kDa. Genome organization: The genome is expressed as a polyprotein of 3255 amino-acid residues, processed by three virus-specific proteinases into ten mature proteins. Hosts: LMV has a worldwide distribution and a relatively broad host range among several families. Weeds and ornamentals can act as local reservoirs for lettuce crops. In particular, many species within the family Asteraceae are susceptible to LMV, including cultivated and ornamental species such as common (Lactuca sativa), prickly (L. serriola) or wild (L. virosa) lettuce, endive/escarole (Cichorium endiva), safflower (Carthamus tinctorius), starthistle (Centaurea solstitialis), Cape daisy (Osteospermum spp.) and gazania (Gazania rigens). In addition, several species within the families Brassicaceae, Cucurbitaceae, Fabaceae, Solanaceae and Chenopodiaceae are natural or experimental hosts of LMV. Genetic control of resistance to LMV: The only resistance genes currently used to protect lettuce crops worldwide are the recessive genes mo11 and mo12 corresponding to mutant alleles of the gene encoding the translation initiation factor eIF4E in lettuce. It is believed that at least one intact copy of eIF4E must be present to ensure virus accumulation. Transmission: LMV is transmitted in a non-persistent manner by a high number of aphid species. Myzus persicae and Macrosiphum euphorbiae are particularly active in disseminating this virus in the fields. LMV is also seedborne in lettuce. The effectiveness of LMV transmission depends on the cultivar and the age of the seed carrier at the inoculation time. Symptoms: The characteristic symptoms on susceptible lettuce cultivars are dwarfism, mosaic, distortion and yellowing of the leaves with sometimes a much reduced heart of lettuce (failure to form heads). The differences in virus strains, cultivars and the physiological stage of the host at the moment of the attack cause different symptom severity: from a very slight discoloration of the veins to severe necrosis leading to the death of the plant.

The eukaryotic translation initiation factor 4E (eIF4E) (the cap-binding protein) is involved in natural resistance against several potyviruses in plants. In lettuce, the recessive resistance genesmo11andmo12againstLettuce mosaic virus(LMV) are alleles coding for forms of eIF4E unable, or less effective, to support virus accumulation. A recombinant LMV expressing the eIF4E of a susceptible lettuce variety from its genome was able to produce symptoms inmo11ormo12varieties. In order to identify the eIF4E amino acid residues necessary for viral infection, we constructed recombinant LMV expressing eIF4E with point mutations affecting various amino acids and compared the abilities of these eIF4E mutants to complement LMV infection in resistant plants. Three types of mutations were produced in order to affect different biochemical functions of eIF4E: cap binding, eIF4G binding, and putative interaction with other virus or host proteins. Several mutations severely reduced the ability of eIF4E to complement LMV accumulation in a resistant host and impeded essential eIF4E functions in yeast. However, the ability of eIF4E to bind a cap analogue or to fully interact with eIF4G appeared unlinked to LMV infection. In addition to providing a functional mutational map of a plant eIF4E, this suggests that the role of eIF4E in the LMV cycle might be distinct from its physiological function in cellular mRNA translation.

The effect of growing seedlings under screen house during different periods and transplanting at different distances from the source of inoculum were evaluated for viral disease effect on the production of lettuce Veronica cultivar. The experiments were conducted from June to September, 1999, adopting an entirely randomized experimental design with three replications. Seven periods of seedling protection and three planting distances from the virus inoculum’s source were tested. After each period of protection, the seedlings were maintained under anti-aphid screen and transferred to a greenhouse exposed to natural virus infection until they reached the stage of transplanting. No significant differences among the treatments regarding the time of protection of the seedlings, were observed. A gradient of production was also verified, that is, the further from the source of inoculum, the larger the productivity. The induced symptoms were attributed to LMV and LeMoV. Com o objetivo de avaliar os efeitos dos períodos de permanência das mudas de alface em telado antiafídeo e da distância da fonte principal de inóculo na ocorrência de fitoviroses e na produção de alface, cv. Verônica, foram conduzidos três experimentos em Maringá, Estado do Paraná, durante o período de junho a setembro de 1999. Adotou-se o delineamento experimental inteiramente casualizado, com três repetições, quando foram avaliados sete períodos de proteção das mudas: 0, 5, 10, 15, 20, 25 e 30 dias. Após cada período de proteção, as mudas foram transferidas para um abrigo com cobertura plástica e expostas a insetos vetores dos vírus, até atingirem o ponto de transplante. Os experimentos foram instalados, respectivamente, a distâncias que variaram entre 20 e 41 m, 41 e 62 m e 62 e 83 m da fonte principal de inóculo - cultura com maior idade e apresentando sintomas característicos de infecção viral. Não se verificou efeito dos períodos de proteção das mudas na severidade dos sintomas de viroses e nas características de crescimento e produção. O efeito da distância da fonte de inoculo, entretanto, foi inversamente proporcional � severidade dos sintomas de viroses e diretamente proporcional ao crescimento e produção da alface. Os sintomas induzidos - danos - foram atribuídos ao LMV e ao LeMoV.