Screening of Some Biotic and Abiotic Agents for Controlling Maize Late Wilt Disease Caused by <i>Magnaporthiopsis maydis</i>

Abstract

Current work was conducted to evaluate 4 biotic and 8 abiotic agents, as seed soaking, against maize late wilt disease caused by Magnaporthiopsis maydis. It was performed in vitro and/or in vivo to achieve satisfied degree of disease control. Obtained results revealed that all tested fungicides in all doses were in vitro effective and completely inhibited M. maydis growth. Used fungicides herein ranked the first for antifungal activity followed by Pseudomonas fluorescens, sodium and potassium silicate. Greenhouse and field experiments showed that, Strong-X fungicide exhibited stability in its activity against the disease incidence with significant differences compared with the control. However, yield parameters obtained following the tested fungicides, even with the high application dose, were insignificantly different from the control. Meanwhile, potassium and sodium silicate as well as P. fluorescens were equivalent or superior the tested fungicides in protecting maize plants from wilt. Furthermore, sodium silicate significantly enhanced the 100-kernel weight (100KW) and net grains weight of ear (NGWE) per plant, whereas potassium silicate increased NGWE/plant only. On the other hand, soaked seeds in the suspension of Enteromorpha flexuosa and Ulva fasciate exhibited high performance for disease reduction with both application doses in the field and significantly reflected only on NGWE/plant. It could be concluded that the ecofriendly agents; potassium silicate, sodium silicate, P. fluorescens, E. flexuosa and U. fasciate are promising for control the disease. Further studies are needed to test other application methods of these promising materials against maize late wilt disease to maximize the obtained benefit.