Abstract

ALCANTARA-MENDOZA, Susana et al. Detection and Evaluation of Maize Bushy Stunt Phytoplasm in the State of Veracruz, Mexico. Rev. mex. fitopatol [online]. 2010, vol.28, n.1, pp.34-43. ISSN 2007-8080.

A maize disease of unknown etiology appeared in the state of Veracruz, Mexico, during 2003-2004. Diseased plants were characterized by premature death, proliferation and poor ear growth, sterility in both male and female flowers, stalk rot, leaves with white spots, yellowing and reddening on leaf margins, leaf stripes, and necrosis. Maize Bushy Stunt (MBS) phytoplasma was PCR detected and associated with plants with yellow and red leaves and ear proliferation in Tlalixcoyan, Cosoleacaque and Paso de Ovejas counties in 2006 and 2007. Ten maize genotypes were evaluated for incidence and severity of the disease and grain yield performance in an experimental plot in Tlalixcoyan, Ver. in 2007. MBS was PCR detected in CP-562, 30F83, 30F92, Orca, 30F96, Nutria and Asgrow 7573; whereas Pioneer 3086, 30F97 y CP-560 were MBS negative. Highest incidence and severity was detected in 30F83 (27 %, 0.29), AS-7573 (21 %, 0.14) and 30F97 (21 %, 0.15). Best grain yield was produced by AS-7573 (5.4 ton ha^-1), Orca (4.7 ton ha^-1), and 30F97 (4 ton ha^-1). Positive correlation was obtained between incidence and severity of the disease (r=0.69**), incidence and number of symptomatic ears (r=0.43**) and severity with decrease in weight of healthy grain (r=0.51**). There was no correlation between disease and yield.

Keywords : Maize; yield; incidence; severity; PCR.