{"title":"Assessment of Downy mildew Resistance (Peronospora farinosa) in a Quinoa (Chenopodium quinoa Willd.) Germplasm","authors":"Manal Mhada, BrahimEzzahiri, Ouafae Benlhabib","volume":87,"journal":"International Journal of Agricultural and Biosystems Engineering","pagesStart":277,"pagesEnd":281,"ISSN":"1307-6892","URL":"https:\/\/publications.waset.org\/pdf\/9997868","abstract":"<p>Seventy-nine accessions, including two local wild species (<em>Chenopodium album<\/em> and <em>C. murale<\/em>) and several cultivated quinoa lines developed through recurrent selection in Morocco were screened for their resistance against <em>Peronospora farinose,<\/em> the causal agent of downy mildew disease. The method of artificial inoculation on detached healthy leaves taken from the middle stage of the plant was used. Screened accessions showed different levels of quantitative resistance to downy mildew as they were scored through the calculation of their area under disease progress curve and their two resistance components, the incubation period and the latent period. Significant differences were found between accessions regarding the three criteria (Incubation Period, Latent Period and Area Under Diseases Progress Curve). Accessions M2a and S938\/1 were ranked resistant as they showed the longest Incubation Period (7 days) and Latent Period (12 days) and the lowest area under diseases progress curve (4). Therefore, M24 is the most susceptible accession as it has presented the highest area under diseases progress curve (34.5) and the shortest Incubation Period (1 day) and Latent Period (3 days). In parallel to this evaluation approach, the accession resistance was confirmed under the field conditions through natural infection by using the tree-leaf method. The high correlation found between detached leaf inoculation method and field screening under natural infection allows us to use this laboratory technique with sureness in further selection works.<\/p>\r\n","references":"[1]\tS.E. Jacobsen, Mujica A, Jensen CR. The resistance of quinoa (Chenopodium quinoa Willd.) to adverse abiotic factors. Food Rev Int 2003;19(1-2):99-109.\r\n[2]\tS.E. Jacobsen, Mujica A, Stolen. O. Salt tolerance of quinoa during germination. Agronomia Tropical. 1998;48:359-66.\r\n[3]\tJ. Risi, Galwey NW. Chenopodium quinoa of the Andes: a crop for temperate latitudes. New Crops Food 1989;21:329-52.\r\n[4]\tS. Danielsen, Munk L. Evaluation of disease assessment methods in quinoa for their ability to predict yield loss caused by downy mildew. Crop Prot. 2004;23:219-28.\r\n[5]\tS. Danielsen, Jacobsen SE, Echegaray J, Ames T. Impact of downy mildew on the yield of quinoa. Lima: 2001.\r\n[6]\tS. Danielsen, Jacobsen SE, Hockenhull J. First report of downy mildew of quinoa caused by Peronospora farinosa f.sp. chenopodii in Denmark. Plant Dis. 2002;86:1175.\r\n[7]\tW. J. Byford, Downy mildews of beet and spinash, in The downy mildews. 1981, Academic Press: London. p. 531-543.\r\n[8]\tI. Herath, Stoddard F, Marshall D. Evaluating faba beans for rust resistance using detached leaves. Euphytica. 2001;117:47-57.\r\n[9]\tO. Benlhabib,Atifi M, Jellen E, Jacobsen S. The introduction of a new Peruvian crop \"quinoa\u201d to a rural community in Morocco. European Society of Agronomy Proceedings Copenhagen, Denmark. 2006:881-2.\r\n[10]\tT. L. Carver, Adaigbe ME. Effects of oat genotype, leaf age and position and incubation humidity on germination and germling development by Erysiphe graminis f. sp. avenae. Mycol Res 1990;94:18-26.\r\n[11]\tG. Shaner, Finney RE. The effect of nitrogen fertilization on the expression of slow mildewing resistance in Knox wheat. Phytopathology. 1977;67:1051-6.\r\n[12]\tR Development Core Team. R: A language and environment for statistical computing. R Foundation for statistical omputing; 2013.\r\n[13]\tD. Pontier, Tronchet M, Rogowsky P, Lam E, Roby D. Activation of hsr203J, a plant gene expressed during incompatible plant-pathogen interactions, is correlated with programmed cell death. . Mol Plant Microbe Interact. 1998;11:544-54.\r\n","publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 87, 2014"}