MARKERS RELATED TO TOLERANCE OR SENSITIVITY TO LATE WILT DISEASE IN MAIZE

Abstract

-Sixteen isolates of Magnaporthiopsis maydis were isolated from maize plants showing typical late wilt symptoms, collected from fields at seven different governorates(Beheira ,Kafr-Elsheikh, Monufia, Faiym, Minya ,Assiut and Sohag)in Egypt. 2- Molecular identification for the sixteen isolates of M.maydis were carried out using PCR specific primer . 3-The sixteen isolates of M.maydis were grown on PDA medium for 6 days at 27°C , all isolates were rhizoid in growth form , raised in growth elevation and filiform in growth margin but different in mycelial color which were white, white gray and dark olive. 4-The faster isolate in growth on PDA medium was S3 while the slowest was A2. 5- Pathogenicity test for the sixteen isolates of M. maydis was carried out in green house conditions by using single cross hybrid pioneer 3062.Isolates F13 and F14 were the most virulence (33.33% infection )while the lowest was Mi5 (10% infection). 6- Six RAPD molecular marker were used to study the molecular diversity among the sixteen isolates of M. maydis , 32 bands were generated with average 5.33bands per primer, the polymorphic bands were 93.88% with average 5 polymorphic bands per primer, the most polymorphic primers were 1,2,3 and 6 whereas the polymorphic information contents ranged from 0.20 to 0.39 with average of 0.29