Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Seed health testing of corn for Cephalosporium maydis.

Abstract

In seed health testing of 13 maize cultivars, potato dextrose yeast extract agar medium was more efficient than blotters in detecting C. maydis. The fungus could be detected after 2 days of incubation at 20°C under 12 hour alternating cycles of near ultraviolet light (NUV) and darkness. The fungus was distinguished in 12 seed samples on agar medium, however only 9 samples were detected on blotters. Maximum infection rate in a seed sample of cultivar Giza 2 was 9% on agar medium, compared with 5% on blotters. C. maydis was detected in a higher percentage of white maize seeds (1-9%) than in yellow cultivars (1-3%). C. maydis was detected in different ear parts, i.e., ear branch, cob, seeds, ear husks and silk of naturally infected maize cultivars. It was mostly manifested in the branch followed by cob, seeds, husks and silk. C. maydis is internally and externally seedborne in maize as it was detected at higher levels in the embryo and in both the endosperm and coat of the 13 tested seed samples, with the exception of seeds of cultivar Amon in which the fungus was confined to the seed coat.