Comportamiento de hibridos de maiz a la mancha ocular (Kabatiella zeae) y al tizon foliar comun (Exserohilum turcicum)

FORMENTO, A.N.; NOVELLI, L.E.,; PIOLI, R.; PLOPER, L. D.

Rosario

Congreso; Maiz HD - X Congreso Nacional de Maiz; 2014

Asociacion de Ingenieros Agronomos del Norte de Buenos Aires

In late-planted corn (Zea mays L.), December to early January instead of September-October, favorable environmental conditions allow the development of foliar diseases, especially eyespot (ES), caused by Kabatiella zeae, and northern leaf blight (NLB), produced by Setosphaeria turcica (anamorph Exserohilum turcicum). The aim of this study was to characterize the reaction of maize hybrids to ES and NLB during the 2012/2013 growing season. Template hybrids (M 505 and 510 HXRR2 PW) and tropical hybrids (2K 562 y 2A 120 HXRR2) were planted on 26-12-2012 at INTA EEA Paraná on a Mollisol soil with over 15 years in zero tillage. Previous crops were wheat/soybean (2009); corn (2010) and wheat/soybean (2011). Fertilizers (P and N) were applied at planting and growth stage V2. On 23/04/2013, at growth stage R5 (dent grain) the hybrid reaction was assessed using the scale of Camochena et al. (2008) for ES and the Bleicher scale (1988) for NLB. The experimental design was a randomized complete blocks with two replications. Five leaves, including ear leaf (EL), EL-2, EL-1, EL+1, and EL+2 on 10 plants per replication (n=100) were evaluated. All values expressed as a percentage were transformed (arcs√%), analyzed by ANOVA, and treatments means compared with LSD 5%. The incidence of ES and NLB was 100% and 8.2%, respectively. The severity ranged between 1 and 8.75% for ES and between 0.4 and 0.9% for NLB. Highly significant differences (p