Evaluación de dos elicitores de síntesis química y dos microorganismos para el control de roya blanca (Albugo tragopogonis pers.) en tres variedades de girasol ornamental

Abstract

The present investigation aimed to evaluate the effect of two elicitors of chemical synthesis and two microorganisms for the control of white rust (Albugo tragopogonis) in three varieties of ornamental sunflower, in the sector San Martin de Veranillo, Riobamba canton, Chimborazo province. The experiment was carried out under a randomised complete block design (RCBD) with two factors, factor A (Varieties) and factor B (elicitors) with four replications and 15 treatments, and the variables evaluated were: Percentage of yield at 15 days after transplanting (dat), plant height at 30, 40 and 50 dat, stem diameter at 30, 40 and 50 dat, diameter of the seedhead at the cutting point was made at 40 dat for the variety Vicent's Fresh, 50 dat for the variety Vicent's Choice and 70 dat for the variety Sunbright Golden Yellow, percentage of incidence and severity every 30, 40 and 50 dat, for the determination of severity a scale of affectation of Albugo tragopogonis was designed, using as reference the different levels and economic analysis of the treatments. These variables were analysed statistically using the R program. The results showed that T1 (Vicent's Choice + salicylic acid) generated the greatest height with 94.6 cm at 50 dat, the earliest variety is Vicent's Fresh, the percentage of severity in the treatment T6 (Vicent's Choice + Potassium Phosphite) generated the lowest degree of affection with 0.9%. Thus, it is concluded that T5 (Vicent's Fresh + Potassium Phosphite) generated the best Minimum Acceptable Rate of Yield with 100.70% and a B/C of 2.01 USD. It is recommended to carry out studies with potassium phosphite in combination with fungicides for the control of white rust (Albugo tragopogonis).