DOCSLIB.ORG

Obtaining Resistant Lettuce Progenies to Downy Mildew

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Obtaining Resistant Lettuce Progenies to Downy Mildew CASTOLDI R; CHARLO HCO; MELO DM; CANDIDO WS; VARGAS PF; DALPIAN T; BRAZ LT. 2014. Obtaining resistant lettuce progenies to downy mildew. Horticultura Brasileira 32: 69-73. Obtaining resistant lettuce progenies to downy mildew Renata Castoldi1; Hamilton CO Charlo2; Danilo M Melo1; Willame S Candido1; Pablo F Vargas3; Tagli Dalpian4; Leila T Braz1 1UNESP-FCAV, Depto. Prod. Vegetal, Rod. Prof. Paulo Donato Castellane s/n, 14884-900 Jaboticabal-SP; [email protected]; melo. [email protected]; [email protected]; [email protected] 2IFTM, R. João Batista Ribeiro 4000, Mercês, 38064-790 Uberaba-MG; [email protected]; 3UNESP, R. Nelson Brihi Badur 430, Vila Tupy, Registro-SP; [email protected]; 4CATI, Casa da Agricultura de Ibirá, Av. Gabriel Sanches 725, 15860-000 Ibirá-SP; [email protected] ABSTRACT RESUMO Lettuce is the most consumed leafy vegetable in Brazil. Its Obtenção de progênies de alface crespa resistentes ao míldio production, nonetheless, is increasing in difficulties mainly due to A alface é a hortaliça folhosa mais consumida no Brasil. No en- the infestation of producing areas with Bremia lactucae. Thus, the tanto, a dificuldade em produzi-la vem aumentando, principalmente use of horizontal resistant cultivars is the most viable alternative in pela infestação das áreas de produção por Bremia lactucae, sendo o controlling progress of disease. So, the objective of this study was uso de cultivares com resistência horizontal, a alternativa mais viável to obtain resistant lettuce progenies to the races of downy mildew: no controle da doença. Diante do exposto, o objetivo do presente SPBl:01, SPBl:02, SPBl:03, SPBl:04, SPBl:05, SPBl:06 and SPBl:07. trabalho foi obter progênies de alface crespa resistentes às raças de The breeding consisted of two stages: crossover of parentals to obtain míldio SPBl:01, SPBl:02, SPBl:03, SPBl:04, SPBl:05, SPBl:06 e the resistant lettuce progenies and endurance test of the progeny SPBl:07. O trabalho de melhoramento consistiu de duas etapas: cru- to B. lactucae races. The parentals used to obtain progenies with zamento dos parentais para obtenção das progênies de alface crespa resistance factor R-18 and R-38 were: JAB 4-13-7 and JAB 4-13-7. resistentes e teste de resistência das progênies às raças de B. lactucae. The Pedigree method was used for obtaining the progeny, using as Os parentais utilizados na obtenção das progênies resistentes foram default selections the Hortência cultivar and JAB 4-13-7genotype. Argeles e linhagem JAB 4-13-7, visando a obtenção de progênies After selection and selfing of the plants in the field, the resistance or de alface do tipo crespa, com os fatores de resistência R-18 e R-38. susceptibility test was realized, by inoculation of the progenies from Para tanto, adotou-se o método genealógico, tendo como padrão, para the crosses, with mixture of distilled water + sporangia of B. lactucae as seleções, a cultivar Hortência e o genótipo JAB 4-13-7. Após a races SPBl:01, SPBl:02, SPBl:03, SPBl:04, SPBl:05, SPBl:06 and seleção e autofecundação das plantas no campo, efetuou-se o teste SPBl:07 obtained from isolates collected in the years 2008-2010. de resistência ou suscetibilidade, por meio da inoculação nas pro- Fifteen days after inoculation, the seedlings were selected as resistant gênies oriundas dos cruzamentos, de uma mistura de água destilada or susceptible, discarding those presenting sporulation and necrotic + esporângios de B. lactucae das raças SPBl:01, SPBl:02, SPBl:03, spots caused by B. lactucae. Through the Pedigree method we found SPBl:04, SPBl:05, SPBl:06 e SPBl:07 obtidas de isolados coletados 69 progenies F with good agronomic characteristics. However, after 3 nos anos de 2008 a 2010. Quinze dias após a inoculação, as plântulas resistance or susceptibility test, only 19 showed all the plants resistant foram selecionadas, descartando aquelas que possuíam esporulação e to downy mildew. pontos necróticos causados por B. lactucae. Pelo método genealógico, selecionaram-se 69 progênies F3 com boas características agronômi- cas. No entanto, após o teste de resistência ou suscetibilidade, somente 19 apresentaram todas as plantas resistentes ao míldio. Keywords: Lactuca sativa, resistance factor, Bremia lactucae. Palavras-chave: Lactuca sativa, fatores de resistência, Bremia lactucae. (Recebido para publicação em 30 de abril de 2013; aceito em 1 de novembro de 2013) (Received on April 30, 2013; accepted on November 1, 2013) he lettuce (Lactuca sativa) is one of the Bremia lactucae, etiologic agent of progression can be reduced by the use Tthe most important vegetable crops downy mildew of lettuce. of various control procedures, such as grown worldwide, both in volume and The downy mildew is particularly management of irrigation shift, in order value traded, presenting great consumer important in environmental conditions not to prolong the duration of wetness acceptance (Vieira & Barreto, 2006), of high humidity and mild to low and/or ideal frequency of application mainly because it is a good source of temperature, causing significant of fungicides. However, the most vitamins (A1, B1, B2, B5 and C) and economic losses to producers (Lebeda viable alternative is to develop resistant minerals (Ca, Fe, Mg, P, K and Na), et al., 2001). According to Su et al. varieties, as it is the only economically besides showing reduced caloric content (2004), the optimum temperature for sustainable and effective method of (Menezes et al., 2001). However, many maximum sporulation of B. lactucae control (Beharav et al., 2006). pathogens limit the production in Brazil occurs at 15°C. In lettuce, breeding programs and in the world, among these pathogen, Theoretically, the rate of the disease aiming resistance to downy mildew, Hortic. bras., v. 32, n. 1, jan. - mar. 2014 69 R Castoldi et al. it is important to know the diversity The set of races of B. lactucae may plant, minimizing the problems of of races of B. lactucae, and the gene differ in different countries, mainly overcoming resistance, very common that confers resistance to each of these because of the changes of environmental in the development of lettuce cultivars races, for subsequent transfer of this conditions and in the use of planted resistant to downy mildew. gene to cultivars with good agronomic materials. As the most part of the lettuce In order to obtain progenies with characteristics. For this, it is necessary to cultivars planted in Brazil is imported, resistance to the seven races of B. use cultivars named differentials, which, many of these cultivars, characterized lactucae identified, so far, in the state according to Van Ettekoven & Van Der as resistant to mildew, when grown of São Paulo, the genealogical method Arend (1999), are divided into four under Brazilian conditions, may not was used, considered as a standard for groups, assigning values from 1 to 32 present resistance to the phytopathogen, selections the cultivar Hortência [a to each cultivar, possessing each one a not ensuring, in this way, the Brazilian cultivar of the crisp-leaf group, which gene Dm (Downy mildew) or resistance producer, the disease control in planting presents a cycle of 55 to 60 days; big factor (R). areas. and uniform plants, adapted for growing Physiological races are identified or The resistance depends on the throughout the year in conventional or differentiated by the reaction they cause host genotype as well as the variant hydroponic cultivation; with big leaves in a selected group of hosts (Bueno et of the pathogen, both affected by the and good base of plant and, tolerant to al., 2001). environment. Therefore, knowledge of early bolting and to tip burn (Hortec, The genetic control of resistance the physiological races is a prerequisite 2011)]; as well as the JAB 4-13-7 strain. to downy mildew is due to a dominant for a rigorous and successful test in the The crosses and selections were gene (Dm) and its recessive allele that processes of selection of resistant plants carried out in a greenhouse, from confers susceptibility (dm) (Sala, 2011). (Lima et al., 2005). 01/30/09 to 11/14/10. According to Costa et al. (2003), the Given the above, this study aimed The seeding was performed on genes DM-17, DM-18, R-36, R-37, to obtain progenies of crisp-leaf 01/3/09, in expanded polystyrene trays R-38 and R-40, confer resistance to lettuce resistant to races SPBl:01, with capacity for 288 cells, filled with downy mildew races found in Brazil SPBl:02, SPBl:03, SPBl:04, SPBl:05, substrate Plantmax®HA. The trays were so far. SPBl:06 and SPBl:07, since they are placed under protected cultivation, The genetic interaction between the predominant races in the state of São arch type, with 15 m long, 7 m wide, Bremia lactucae and lettuce has been Paulo (Souza et al., 2011). 3 m ceiling height and a low density studied, and a gene-to-gene relationship polyethylene cover with thickness has been demonstrated. Dominant MATERIAL AND METHODS of 150 microns. The irrigation was resistance genes (Dm) correspond performed twice a day. to dominant avirulence genes (Avr). The breeding program consisted of The transplant was performed 31 The combination of gene Dm and a two phases: Parental cross and test of days after sowing, in greenhouse, when corresponding avirulence (Avr) gene resistance of progenies to races of B. the plants presented 3 or 4 definitive results in an incompatible interaction, lactucae. leaves. The spacing used was 0.50x1.00 expressed as the host hypersensitivity The parental crosses used to obtain m for a better crop management and in (Bonnier et al., 1994). resistant progenies were: Argeles order to perform the crossings. For this, According to Matiello et al.
Load more

Recommended publications
  • Report of a Working Group on Leafy Vegetables: First Meeting
    European Cooperative Programme for Plant Genetic Report of a Working Resources ECP GR Group on Leafy Vegetables First Meeting, 13-14 October 2005, Olomouc, Czech Republic L. Maggioni, A. Lebeda, I. Boukema and E. Lipman, compilers IPGRI and INIBAP operate under the name Bioversity International Supported by the CGIAR European Cooperative Programme for Plant Genetic Report of a Working Resources ECP GR Group on Leafy Vegetables First Meeting, 13-14 October 2005, Olomouc, Czech Republic L. Maggioni, A. Lebeda, I. Boukema and E. Lipman, compilers ii REPORT OF A WORKING GROUP ON LEAFY VEGETABLES: FIRST MEETING Bioversity International is an independent international scientific organization that seeks to improve the well- being of present and future generations of people by enhancing conservation and the deployment of agricultural biodiversity on farms and in forests. It is one of 15 centres supported by the Consultative Group on International Agricultural Research (CGIAR), an association of public and private members who support efforts to mobilize cutting-edge science to reduce hunger and poverty, improve human nutrition and health, and protect the environment. Bioversity has its headquarters in Maccarese, near Rome, Italy, with offices in more than 20 other countries worldwide. The Institute operates through four programmes: Diversity for Livelihoods, Understanding and Managing Biodiversity, Global Partnerships, and Commodities for Livelihoods. The international status of Bioversity is conferred under an Establishment Agreement which, by January 2008, had been signed by the Governments of Algeria, Australia, Belgium, Benin, Bolivia, Brazil, Burkina Faso, Cameroon, Chile, China, Congo, Costa Rica, Côte d’Ivoire, Cyprus, Czech Republic, Denmark, Ecuador, Egypt, Ethiopia, Ghana, Greece, Guinea, Hungary, India, Indonesia, Iran, Israel, Italy, Jordan, Kenya, Malaysia, Mali, Mauritania, Morocco, Norway, Oman, Pakistan, Panama, Peru, Poland, Portugal, Romania, Russia, Senegal, Slovakia, Sudan, Switzerland, Syria, Tunisia, Turkey, Uganda and Ukraine.
    [Show full text]
  • Effector Identification in the Lettuce Downy Mildew Bremia Lactucae By
    bs_bs_banner MOLECULAR PLANT PATHOLOGY (2012) 13(7), 719–731 DOI: 10.1111/J.1364-3703.2011.00780.X Effector identification in the lettuce downy mildew Bremia lactucae by massively parallel transcriptome sequencing JOOST H. M. STASSEN1, MICHAEL F. SEIDL2,3, PIM W. J. VERGEER1, ISAÄC J. NIJMAN4, BEREND SNEL2,3, EDWIN CUPPEN4 AND GUIDO VAN DEN ACKERVEKEN1,3,* 1Plant–Microbe Interactions, Department of Biology, Utrecht University, Padualaan 8, 3508 CH Utrecht, the Netherlands 2Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, Padualaan 8, 3508 CH Utrecht, the Netherlands 3Centre for BioSystems Genomics (CBSG), Wageningen University, Binnenhaven 5, 6709 PD Wageningen, the Netherlands 4Hubrecht Institute, Developmental Biology and Stem Cell Research, KNAW and University Medical Center Utrecht, Uppsalalaan 8, Utrecht, the Netherlands agent of the Irish potato famine, and P. ramorum, which causes SUMMARY sudden oak death. The downy mildews have a narrow host range, Lettuce downy mildew (Bremia lactucae) is a rapidly adapting for instance Hyaloperonospora arabidopsidis grows only on living oomycete pathogen affecting commercial lettuce cultivation. Arabidopsis thaliana plants, Plasmopara viticola is an important Oomycetes are known to use a diverse arsenal of secreted proteins grape pathogen and Bremia lactucae is the most important patho- (effectors) to manipulate their hosts. Two classes of effector are gen of lettuce (Lactuca sativa). The control of B. lactucae is an known to be translocated by the host: the RXLRs and Crinklers. To increasingly difficult task as fungicides have been phased out gain insight into the repertoire of effectors used by B. lactucae to because of environmental concerns, and fungicide resistance is manipulate its host, we performed massively parallel sequencing becoming more widespread (Brown et al., 2004).
    [Show full text]
  • Genetic Variability and Distance Between Lactuca Serriola L
    Acta Bot. Croat. 77 (2), 172–180, 2018 CODEN: ABCRA 25 DOI: 10.2478/botcro-2018-0019 ISSN 0365-0588 eISSN 1847-8476 Genetic variability and distance between Lactuca serriola L. populations from Sweden and Slovenia assessed by SSR and AFLP markers Michaela Jemelková1, Miloslav Kitner1, Eva Křístková1, Ivana Doležalová2, Aleš Lebeda1* 1 Palacký University in Olomouc, Faculty of Science, Department of Botany, Šlechtitelů 27, 783 71 Olomouc, Czech Republic 2 Department of Genetic Resources for Vegetables, Medicinal, and Special Plants of Crop Research Institute in Olomouc, Šlechtitelů 29, 783 71 Olomouc, Czech Republic Abstract – The study involved 121 samples of the common weed, Lactuca serriola L. (prickly lettuce), represent- ing 53 populations from Sweden and Slovenia. The seed materials, originating from different habitats, were re- generated and taxonomically validated at the Department of Botany, Palacký University in Olomouc, Czech Re- public. The morphological characterizations of the collected plant materials classified all 121 samples as L. serriola f. serriola; one sample was heterogeneous, and also present was L. serriola f. integrifolia. Differences in the amount and distribution of the genetic variations between the two regions were analyzed using 257 ampli- fied fragment length polymorphism (AFLP) and 7 microsatellite (SSRs) markers. Bayesian clustering and Neigh- bor-Network were used for visualization of the differences among the samples by country. Under the Bayesian approach, the best partitioning (according to the most frequent signals) was resolved into three groups. While the absence of an admixture or low admixture was detected in the Slovenian samples, and the majority of the Swedish samples, a significant admixture was detected in the profiles of five Swedish samples collected near Malmö, which bore unique morphological features of their rosette leaves.
    [Show full text]
  • Bremia Lactucae)
    International Journal of Forestry and Horticulture (IJFH) Volume 4, Issue 2, 2018, PP 1-6 ISSN No. (Online) 2454–9487 DOI: http://dx.doi.org/10.20431/2454-9487.0402001 www.arcjournals.org Method Optimization Studies on Inoculation and Isolation of the Causal Agent of Lettuce Downy Mildew (Bremia Lactucae) Razieh Ebrahimzadeh1, F. Sara Dolar1*, Kenan Sönmez2, Ş. Şebnem Ellialtıoğlu3 1 Ankara University, Faculty of Agriculture, Department of Plant Protection, Ankara, Turkey. 2Eskişehir Osmangazi University, Faculty of Agriculture, Department of Horticulture, Eskişehir, Turkey. 3Ankara University, Faculty of Agriculture, Department of Horticulture, Ankara, Turkey. *Corresponding Author: F. Sara Dolar, Department of Plant Protection, Faculty of Agriculture, Ankara University, Ankara, Turkey. Abstract: Downy mildew disease caused by Bremia lactucae causes one of the most devastating diseases of lettuce worldwide. An obligat parasite, B.lactucae’s sporulation in unnatural environments and storage is more difficult than necrotrophic pathogens and some special methods are needed to be developed. For this aim, disease samples were collected during 2016 lettuce growing seasons. The all samples were stored at -20 °C and -80 °C. Small leaf parts showing symptoms from the samples were dissected and spores were scraped by various methods. The spore suspensions were obtained using three methods (keep at room illumination+room temperature, room illumination+stored in ice, darkness+room temperature). In order to determine the suitable inoculation method, seedling, and detached leaf tests (blotter, floating, waxed slide test and water agar methods) were performed. A series of petri plates and seedlings were kept at 13±1 °C in the climate chamber and another series of assay were incubated at 18-21 °C until sporulation.
    [Show full text]
  • Phylogenetic Relationships of Plasmopara, Bremia and Other
    Mycol. Res. 108 (9): 1011–1024 (September 2004). f The British Mycological Society 1011 DOI: 10.1017/S0953756204000954 Printed in the United Kingdom. Phylogenetic relationships of Plasmopara, Bremia and other genera of downy mildew pathogens with pyriform haustoria based on Bayesian analysis of partial LSU rDNA sequence data Hermann VOGLMAYR1, Alexandra RIETHMU¨LLER2, Markus GO¨KER3, Michael WEISS3 and Franz OBERWINKLER3 1 Institut fu¨r Botanik und Botanischer Garten, Universita¨t Wien, Rennweg 14, A-1030 Wien, Austria. 2 Fachgebiet O¨kologie, Fachbereich Naturwissenschaften, Universita¨t Kassel, Heinrich-Plett-Strasse 40, D-34132 Kassel, Germany. 3 Lehrstuhl fu¨r Spezielle Botanik und Mykologie, Botanisches Institut, Universita¨tTu¨bingen, Auf der Morgenstelle 1, D-72076 Tu¨bingen, Germany. E-mail : [email protected] Received 28 December 2003; accepted 1 July 2004. Bayesian and maximum parsimony phylogenetic analyses of 92 collections of the genera Basidiophora, Bremia, Paraperonospora, Phytophthora and Plasmopara were performed using nuclear large subunit ribosomal DNA sequences containing the D1 and D2 regions. In the Bayesian tree, two main clades were apparent: one clade containing Plasmopara pygmaea s. lat., Pl. sphaerosperma, Basidiophora, Bremia and Paraperonospora, and a clade containing all other Plasmopara species. Plasmopara is shown to be polyphyletic, and Pl. sphaerosperma is transferred to a new genus, Protobremia, for which also the oospore characteristics are described. Within the core Plasmopara clade, all collections originating from the same host family except from Asteraceae and Geraniaceae formed monophyletic clades; however, higher-level phylogenetic relationships lack significant branch support. A sister group relationship of Pl. sphaerosperma with Bremia lactucae is highly supported.
    [Show full text]
  • EPPO Standards 
    EPPO Standards GUIDELINES ON GOOD PLANT PROTECTION PRACTICE LETTUCE UNDER PROTECTED CULTIVATION PP 2/3(2) English oepp eppo European and Mediterranean Plant Protection Organization 1, rue Le Nôtre, 75016 Paris, France APPROVAL EPPO Standards are approved by EPPO Council. The date of approval appears in each individual standard. REVIEW EPPO Standards are subject to periodic review and amendment. The next review date for this set of EPPO Standards is decided by the EPPO Working Party on Plant Protection Products. AMENDMENT RECORD Amendments will be issued as necessary, numbered and dated. The dates of amendment appear in each individual standard (as appropriate). DISTRIBUTION EPPO Standards are distributed by the EPPO Secretariat to all EPPO Member Governments. Copies are available to any interested person under particular conditions upon request to the EPPO Secretariat. SCOPE EPPO guidelines on good plant protection practice (GPP) are intended to be used by National Plant Protection Organizations, in their capacity as authorities responsible for regulation of, and advisory services related to, the use of plant protection products. REFERENCES All EPPO guidelines on good plant protection practice refer to the following general guideline: OEPP/EPPO (1994) EPPO Standard PP 2/1(1) Guideline on good plant protection practice: principles of good plant protection practice. Bulletin OEPP/EPPO Bulletin 24, 233-240. OUTLINE OF REQUIREMENTS For each major crop of the EPPO region, EPPO guidelines on good plant protection practice (GPP) cover methods for controlling pests (including pathogens and weeds). The main pests of the crop in all parts of the EPPO region are considered. For each, details are given on biology and development, appropriate control strategies are described, and, if relevant, examples of active substances which can be used for chemical control are mentioned.
    [Show full text]
  • UC Davis UC Davis Previously Published Works
    UC Davis UC Davis Previously Published Works Title Sporulation of Bremia lactucae affected by temperature, relative humidity, and wind in controlled conditions Permalink https://escholarship.org/uc/item/9j91h7dr Journal Phytopathology, 94(4) ISSN 0031-949X Authors Su, H van Bruggen, AHC Subbarao, K V et al. Publication Date 2004-04-01 Peer reviewed eScholarship.org Powered by the California Digital Library University of California This article is from the April 2004 issue of published by The American Phytopathological Society For more information on this and other topics related to plant pathology, we invite you to visit APSnet at www.apsnet.org Ecology and Epidemiology Sporulation of Bremia lactucae Affected by Temperature, Relative Humidity, and Wind in Controlled Conditions H. Su, A. H. C. van Bruggen, K. V. Subbarao, and H. Scherm First, second, and third authors: Department of Plant Pathology, University of California, Davis 95616; and fourth author: Department of Plant Pathology, University of Georgia, Athens 30602. Current address of H. Su: Alberta Research Council, Vegreville, Alberta, Canada. Current address of A. H. C. van Bruggen: Leerstoelgroep Biologische Bedrijfssystemen, 6709 PG Wageningen, The Netherlands. Accepted for publication 4 December 2003. ABSTRACT Su, H., van Bruggen, A. H. C., Subbarao, K. V., and Scherm, H. 2004. 0.0001) affected the number of cotyledons with sporulation and the Sporulation of Bremia lactucae affected by temperature, relative humid- number of sporangia produced per cotyledon. No sporulation was ob- ity, and wind in controlled conditions. Phytopathology 94:396-401. served at wind speeds of >0.5 m s–1, regardless of RH. In still air, the number of sporangiophores produced per cotyledon increased linearly The effects of temperature (5 to 25°C), relative humidity (81 to 100%), with RH from 81 to 100% (P = 0.0001, r = 0.98).
    [Show full text]
  • Wild Lactuca Species in North America
    Horticulture Publications Horticulture 2019 Wild Lactuca Species in North America A. Lebeda Palacký University E. Křístková Palacký University I. Doležalová Medicinal and Special Plants of Crop Research Institute in Olomouc M. Kitner Palacký University Mark P. Widrlechner Iowa State University, [email protected] Follow this and additional works at: https://lib.dr.iastate.edu/hort_pubs Part of the Agricultural Science Commons, Ecology and Evolutionary Biology Commons, Horticulture Commons, Natural Resources and Conservation Commons, and the Plant Breeding and Genetics Commons The complete bibliographic information for this item can be found at https://lib.dr.iastate.edu/ hort_pubs/39. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Book Chapter is brought to you for free and open access by the Horticulture at Iowa State University Digital Repository. It has been accepted for inclusion in Horticulture Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Wild Lactuca Species in North America Abstract This chapter presents a brief history of the uses of lettuce (Lactuca sativa L.) and its wild North American relatives, and reviews the agricultural importance of lettuce and challenges in its cultivation, in relation to nutritional quality, diseases, pests, and edaphic and climatic limitations. The evolution and taxonomy of the genus Lactuca are presented, with a primary focus on the wild Lactuca species of North America, their characterization, biogeography and distribution, habitat ecology, and genepools. Specific examples of phenotypic variability, genetic diversity and disease resistance of wild Lactuca taxa from both published reports and recent evaluations conducted in our laboratory are also presented.
    [Show full text]
  • I. Albuginaceae and Peronosporaceae) !• 2
    ANNOTATED LIST OF THE PERONOSPORALES OF OHIO (I. ALBUGINACEAE AND PERONOSPORACEAE) !• 2 C. WAYNE ELLETT Department of Plant Pathology and Faculty of Botany, The Ohio State University, Columbus ABSTRACT The known Ohio species of the Albuginaceae and of the Peronosporaceae, and of the host species on which they have been collected are listed. Five species of Albugo on 35 hosts are recorded from Ohio. Nine of the hosts are first reports from the state. Thirty- four species of Peronosporaceae are recorded on 100 hosts. The species in this family re- ported from Ohio for the first time are: Basidiophora entospora, Peronospora calotheca, P. grisea, P. lamii, P. rubi, Plasmopara viburni, Pseudoperonospora humuli, and Sclerospora macrospora. New Ohio hosts reported for this family are 42. The Peronosporales are an order of fungi containing the families Albuginaceae, Peronosporaceae, and Pythiaceae, which represent the highest development of the class Oomycetes (Alexopoulous, 1962). The family Albuginaceae consists of the single genus, Albugo. There are seven genera in the Peronosporaceae and four commonly recognized genera of Pythiaceae. Most of the species of the Pythiaceae are aquatic or soil-inhabitants, and are either saprophytes or facultative parasites. Their occurrence and distribution in Ohio will be reported in another paper. The Albuginaceae include fungi which are all obligate parasites of vascular plants, causing diseases known as white blisters or white rusts. These white blisters are due to the development of numerous conidia, sometimes called sporangia, in chains under the epidermis of the host. None of the five Ohio species of Albugo cause serious diseases of cultivated plants in the state.
    [Show full text]
  • Downy Mildew of Lettuce in Florida1 Lis Rodrigues-Porto, Richard N
    HS1403 Downy Mildew of Lettuce in Florida1 Lis Rodrigues-Porto, Richard N. Raid, and Germán V. Sandoya2 The Importance of Lettuce and opportunities for foodborne pathogens, such as Escherichia coli or Salmonella enterica. Impact of Downy Mildew in Florida The United States produces 15% of the world’s lettuce (Table 1), and Florida ranks third among states, following only California and Arizona (Figure 1). In Florida, lettuce is mostly field grown, with limited production in protected structures. The majority of Florida’s field production is located on the rich organic “muck” soils of the Everglades Agricultural Area (EAA), amounting to over 10,000 acres, primarily in Palm Beach County. The state’s production values for the lettuce crop routinely exceed $80 million annually. In response to a growing demand for organically produced lettuce, production within protected structures (greenhouses) has expanded in recent years. Such facilities offer a distinct advantage in terms of greater environmental Figure 1. Percentage based on production of lettuce planted in control. A recent survey conducted and compiled with California, Arizona, and Florida in the United States according to the USDA Census of Agriculture in 2017. Source: https://www.nass.usda. responses from 240 grower operations in Florida indicated gov/ rapid growth in this type of production within the state of Credits: Lis Natali Rodrigues Porto, UF/IFAS Florida. Causal Organism Lettuce downy mildew (LDM) is the most important LDM is caused by the oomycete Bremia lactucae Regel. disease of lettuce worldwide, with losses of up to 100% Oomycetes were previously considered part of the Fungi reported in individual fields in Florida.
    [Show full text]
  • Marieke J.W. Jeuken the Genetics of Non-Host Resistance to the Lettuce
    Marieke J.W. Jeuken The genetics of non-host resistance to the lettuce pathogen Bremialactucae i n Lactucasaligna Promotor: Prof. Dr. Ir. P.Sta m Hoogleraar in deplantenveredeling , in het bijzonder de selectiemethoden en duurzame resistentie Co-promotor: Dr. P. Lindhout Universitair hoofddocent Leerstoelgroep plantenveredeling Promotiecommissie: Prof. Dr. Ir. A. H. C. van Bruggen, Wageningen Universiteit Prof. Dr. Ir. M. Koornneef, Wageningen Universiteit Dr. Ir. F.P .M . Govers, Wageningen Universiteit Dr. Ir. K.Reinink , RijkZwaan BV, De Lier ^0X201,3^03 Marieke J.W. Jeuken The genetics of non-host resistance to the lettuce pathogen Bremialactucae i n Lactucasaligna Proefschrift ter verkrijging van degraa d van doctor op gezag van derecto r magnificus van Wageningen Universiteit, Prof. Dr. Ir. L. Speelman in het openbaar te verdedigen op woensdag 22 mei 2002 om half twee 's middags in de Aula. 6u ^93? ISBN 90-5808-619-4 Keywords: plant breeding, lettuce, Lactucasativa, Lactuca saligna, Bremia lactucae, downy mildew, genetics,non-hos t resistance, QTL,quantitativ e trait locus, molecular marker, marker assisted selection STELLINGEN 1.D e oude definities van "Dm" en '7?"-genen zijn achterhaald. Het verdient voorkeur om dit onderscheid tebasere n op gekloneerde genen. 2. De extra inspanning die nodig is om AFLP merkers co-dominant te kunnen scoren wordt ruimschoots gecompenseerd door het grote gemak waarmee genetische kaarten met behulp van co-dominante merkers geconstrueerd worden. 3. De niet-waard resistentie van Lactuca saligna tegen Bremia lactucae is de meest waardevolle resistentie voor de sla-veredeling. 4. De Backcross Inbred Line karteringsstrategie kan genen onthullen die verborgen blijven in een F2karteringsbenaderin g (dit proefschrift).
    [Show full text]
  • Crop Profiles -- Washington
    Crop Profile for Lettuce in Washington Prepared: December, 2000 General Production Information ● Percent of U.S. Production: <1.0 ● Rank: #7 in U.S. acres harvested in 1997 ● Acres Harvested: 900 in 1997 (multiple crops on farms in yearly estimate) ● Yield Per Acre: 200 cwt./acre in 1997 for a total of 180,000 cwt./900 acres, with an average market price of $15.10/cwt. ● Value Per Harvested Acre: $3,020 in 1997 ● Total Value of Production: $2,718,000 in 1997 Production Regions Commercial production regions are centered in the Puget Sound area of western Washington, primarily Pierce and King counties. Other counties, such as Thurston, Whatcom, Clark, Island, Kitsap, Okanogan, Snohomish, Spokane, Stevens, and Walla Walla also reported some lettuce acreage in the 1997 Census The Crop Profile/PMSP database, including this document, is supported by USDA NIFA. of Agriculture. General Information Both head lettuce (iceberg, butterhead) and leaf lettuce (green leaf, romaine, red leaf) are grown for fresh markets, primarily located in western Washington and Alaska. The Washington lettuce industry is a niche industry, depending upon markets not utilized by the California lettuce industry. The average farm size is 50 to 60 acres, with the average lettuce field size being five acres. The majority of growers plant green leaf lettuce along with other varieties throughout the season in an effort to meet fluctuating market demands. Most farms plant three or, infrequently, four crops of lettuce per year in staggered plantings. Some growers plant lettuce followed by other vegetable crops such as Chinese cabbage, celery, or radish.
    [Show full text]