Estudio de resistencia y tolerancia de la variabilidad genética de 18 líneas de maíz (Zea mays L), a las enfermedades presentes en Tunshi, parroquia Licto, cantón Riobamba, provincia de Chimborazo

Abstract

This research proposes: to study the resistance and tolerance of 18 corn lines to phytosanitary problems caused by “manchanorteña” (SetosphaeriaturcicaLuter.), “complejo de la mancha de asfalto” (PhyllachoramaydisMaubl.), MonographellamaydisMüller & Samuels, ConiothyriumphyllachoreaMaubl.), “Roya” (PucciniaSorguiSchwein.) ear rot in Tunshi, parish Licto, canton Riobamba, Chimborazo province. The design was randomized complete blocks with 18 treatments and three replications, so that the known disease as norther blot. The strong varieties were: Penipe, chazo, licto y I-102; the rest of the varieties were very strong. In the complejomancha de asfalto did not present symptoms to be quantifiable. In the roya I-103 reached an area under the curve of 246.8 and a percentage of affected area that varies from 0.97%-10.20% considering as resistant, the rest varieties stood at lower ranks. The damage caused by ear rot were higher in the local variety Chazo whit 24,6% considering them as moderate rots, the res obtained lower values. The varieties whith higher performance per hectare were I-103, I-101- I-102 and Chazo whit (4,5-4,1-4) mt/ha. Respectively, however the highest net profit was presented in the rage Chazo whit a value of 2594,15 dollars whit a cost benefit related of 1,59 dollars. It concludes that diseases are not problems but the ear rot is. That varieties of corm that best respond to conditions of Tunshi-Licto, Were I-103, I-101, I-102 and Chazo by physiological, morphological and economic features. It is recommended to continue researching the variety Chazo with emphasis on behavior ear rot

Keywords: Corn, corn varieties, foliar diseases, genetic resistance