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The UN has elected cassava as the food of the 21st century. It has the possibility of full utilization, the leaf is used for animal and human feed, while the handles can be used for propagation or silage. In Brazil, cassava is cultivated with minimal or no use of inputs in a knock down-and-burn system, although with tolerance to acidity and scarcity of resources, continuous cultivation without replacement of exported nutrients may cause depletion of reserves. nutritional and lead to degradation. The objective was to evaluate the phytometry of the Manihot esculenta Crantz variables, when submitted to limestone and plaster application. The experiment was carried out in the field, in 2018, in the experimental area of the Department of Soils, belonging to the Institute of Agrarian Sciences of the Universidade Federal Rural da Amazonia - UFRA, located in the city of Belém, Pará. The experimental design was a randomized block design. 2x3 factorial arrangement, with six replications, totaling 36 experimental units. The factors were: 2 varieties of macaxeira (Caeté and Manteiguinha) and 3 corrections (limestone, plaster, limestone + plaster). The treatments consisted of soil correction with limestone (T1), plaster (T2), and the combination of both (T3), which were implanted the varieties Caeté (C1) and Manteiguinha (C2). The phytometric variables were: plant height (AP), first branch height (APR), leaf fresh matter (MFF), leaf dry matter (MSF), cuttings fresh matter (MFE) and harvest index (CI). The isolated and combined applications of limestone and plaster promoted significant results for the analyzed variables. [ABSTRACT FROM AUTHOR]

Se relaciona la incidencia con la severidad de la roya asiática de la soya, donde los valores generados por las ecuaciones pueden ser usados en cualquier estudio de este patosistema, proporcionando una herramienta para evaluar la incidencia como también la severidad. Se generaron gradientes de la enfermedad mediante el uso de fungicidas y momentos de aplicación, de manera preventiva y curativa. El experimento de campo con el cultivar Nidera 5909 RG, fue distribuido en bloques completos al azar. La intensidad de la roya asiática fue medida en los estratos inferior, medio y superior de la planta, a través de diferentes conteos de incidencia (porcentaje) y severidad (lesiones cm-2, urédias cm-2 y porcentaje) en folíolos. Las regresiones realizadas, presentaron una correlación significativa entre incidencia y severidad a 1% de probabilidad. Con los datos obtenidos, el evaluador puede escoger el método de cuantificación mas razonable o confiable a su criterio para otros trabajos de investigación o aplicar un determinado control de la enfermedad, utilizando las ecuaciones lineales generadas, facilitando el trabajo de cuantificar la roya asiática, bien se busque medir la incidencia (%) o el número de lesiones cm-2, urédias cm-2 o severidad (%).Incidence is related to severity of the Asian soybean rust, where values generated by the equations can be used in any study of this pathosystem, providing a tool to evaluate incidence as well severity. Gradients of the disease were generated by means of the use of fungicides and moments of application, in a preventive and curative way. The field experiment with the cultivar Nidera RG 5909, was distributed in a randomized complete block. The intensity of Asian rust layers was measured in the lower, middle and top of the plant, through various counts of incidence (percentage) and severity (lesions cm-2, uredinia cm-2 and percentage) in leaflets. The regressions showed a significant correlation between incidence and severity at 1% probability. With obtained data, the assessor can choose the most reasonable or reliable quantification method at their discretion for other research or apply a particular disease control, using the linear equations generated, facilitating the work of quantifying Asian soybean rust either seeking to measure the incidence (%) or the number of injuries cm-2, urédias cm-2 or severity (%).