English: tar spot; tar spot of maize; Spanish: mancha de asfalto; mancha negra; mancha negra del maiz; French: tache noire du mais. El “complejo mancha de asfalto” del maíz, su distribución geográfica, requisitos Etiología y manejo de la mancha de asfalto (Phyllachora maydis Maubl.). mancha de asfalto del maiz . Malaguti, G. Subero, L.J.. Access the full text: NOT AVAILABLE. Lookup the document at: google-logo. mancha de asfalto del.
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The reproducibility of the scale was high using the same scale for the assessment of the material, given different evaluators estimated similar severity percentages.
The distribution in this summary table is based on all the information available.
Revista mexicana de fitopatología
The linear regression of the severities estimated by the evaluators produced coefficients of determination that varied within the range of 65 to 91 Table 1.
The logarithmic scale was generated through the 2-Log V1.
High levels of accuracy were observed; r 2 was comprised between the range of 0. Contribution of Reed Herbarium Reed Herbarium. In this study, the symptoms of P. The clypeus stroma of Phyllachora species grows nancha in the epidermis on either side of the leaf and is not an extension of the perithecia Parbery, b. Another member of the fungus complex associated with tar spot is Coniothyrium phyllachoraea pycnidial mais that is considered to be a hyperparasite on Phyllachora. The source of initial inoculum for both fungi is not determined.
Clypeus amphigenous, developing in epidermis, generally circular, 0. Windborne ascospores of P. Table 1 Estimate of the interception parameters b0slope b1and coefficient of determination r2 of the simple linear regression analysis fe between the real and estimated severity of TSC, carried out by 10 evaluators with and without experience in the quantification of diseases.
The precision levels observed indicate that the first contact with the scale is appropriate for successful implementation in the evaluation of TSC. Measures to reduce asflto initial inoculum for a new crop would depend on the source of that inoculum and cultivation practices.
Antiguas variedades de maíz aportan modernas soluciones al complejo de la mancha de asfalto
Cryptogamic Botany, 2 Journal of Agriculture of the University of Puerto Rico, 42 3: Species reported on Sorghum were distinguished by the shape of the ascus from Phyllachora oxysporaand the greater length of ascospores from both P.
Undiagnosed fungus, maize – Guatemala The values of the b 0 intercept were closer to zero for the first group. International Journal of Pest Management, 40 2: Phyllachora species are generally obligate parasites, and cannot be cultured on the usual laboratory media Parbery, b.
Lower leaves should be examined for small, raised, glossy, dark, circular, or oval to irregular, spots, or for brown lesions, often with a dark border, having a dark ascomata at the centres CIMMYT, Given the growing importance, standardized methods are required to quantify disease that allow for reproducible epidemiological methods.
Organizations Top of page Mexico: Biological Control Reduction in size of P. A sequence of 50 photographs of leaves and maize plants with different TSC severity levels was used, previously determining the affected area of each one of them.
The International Seed-Testing Association. Infection may also occur at the 8 to 10 leaf stage Hock et al. Symptoms Top of page Initial symptoms are small, yellow-brown spots on either side of the leaf.
Tests of standard diagrams for field use in assessing the tarspot disease complex of maize Zea mays.
Escala Diagramática de Severidad para el Complejo Mancha de Asfalto del Maíz
The tar spot complex of maize, induced by the fungi Phyllachora maydis and Monographella maydisis a disease of economic importance in Mexico and Central America because it causes severe yield losses.
This has been reported, among others, by Barbosa et al. Where maize [ Zea mays ] is grown continuously in the vicinity, asdalto at sanitation are not likely to be effective.
Ascospores-their liberation and germination. Please consider upgrading your browser to the latest version or installing a new browser. The diagrammatic logarithmic scale for the Rn proposed in this study represents a standardized quantification method for the disease that will help obtain easily reproducible results, due to its high levels of accuracy and precision among several evaluators, therefore, it can be used as supporting material for different kinds of studies related to the quantification of the severity of TSC.
Systematic Mycology and Microbiology Laboratory. Affected ears have reduced weight and loose kernels, and kernels at the ear tip may germinate prematurely CIMMYT, Other types of losses may include reductions in quality of mqncha, plants used for feed, or husks used for food wrapping Bajet et al. El “complejo mancha de asfalto” de maiz, su distribucion geografica, requisition ambientales e importancia economica en Mexico.
Accidental Introduction This has not been reported, but the natural means of dispersal may not be sufficient to explain spread manch environmentally favourable areas of maize cultivation at higher elevations in South America or to islands in the Caribbean. Diseases of minor importance or limited occurrence.
An annotated list of seed-borne diseases. In the field, it has been observed that the maize is first asffalto by P.