International Journal of Agricultural Research and Review

ISSN 2360-7971

Maize Common Smut (Ustilago maydis) Infection Mechanism and Its Management Options


Abstract: Maize indeed plays a crucial role in Ethiopia’s food security, but its productivity faces significant challenges due to maize smut (Ustilago maydis (DC.) Corda). U. maydis poses a serious threat as it can infect different parts of the maize plant, leading to substantial yield losses ranging from 40 to 100%. Understanding the lifecycle of U. maydis is essential for devising effective control strategies. This pathogen exhibits a dimorphic lifestyle, with haploid sporidia that are not infectious but can grow as saprophytes. However, infection occurs when compatible diploid sporidia mate, initiating filamentous growth and ultimately leading to host infection. Teliospores facilitate the pathogen's survival and spread. Implementing good agronomic practices includes removing infected plants before the pathogen bursts, deep plowing, crop rotation, disease-free seed, recommended nitrogen fertilization, and plant density. Using advanced methods like bi-1 gene silencing and UmRrm75 gene deletion could help make maize more resistant to U. maydis and weaken its ability to infect other plants. Additionally, seed dressing with Carboxin 15% and Thiram 13% has proven effective against seed-borne U. maydis. By combining cultural practices, genetic resistance, and chemical control measures, farmers can mitigate the impact of maize smut and improve maize productivity in Ethiopia.

 

Keywords:

 teliospores, maize, smut, karyogamy, gene silencing, gene deletion