Antifungal activities of cyanobacterial filtrate, compost tea, H2O2, garlic oil, barnyardgrass root exudates and Premis fungicide were tested against Cephalosporium maydis, the pathogenic fungus of late wilt disease of maize plants. In vitro and two field trials were carried out during 2015 and 2016 growing seasons under disease nursery conditions. In vitro, cyanobacterial filtrate and 30% premis fungicide were the superior treatments, by them linear growth of C. maydis were prevented totally and fulfillment inhibitions (100 %) were resulted with lowest IC50 values. Cyanobacterial filtrate and 3% H2O2 were more effective in developing grain germination. Disease incidence showed better efficacy due to use 30 % Premis fungicide followed by 3 % H2O2 with massive disease reductions reached 83.21 and 75.37 %, respectively during 2015 season. Effectiveness of the 3 % H2O2 dose was extended to the 2016 season with 5.11 % disease incidence and 73.39 % disease reduction. For grain productivity, remarkable enhancements in the weights of both 10 ears and 1000 grains due to all treatments compared to control were recorded in both seasons. Due to their antifungal activities, qualitative analysis of Cyanobacterial filtrate and barnyardgrass root exudates was assayed on Gas chromatography mass-spectrum (GC-MS). Malonic acid, 2,3-Butandiol, Hexestrol, 12-Crown-4-ether and cis-Vaccenic acid were the major compounds extracted from the cultured blue-green algae. Whereas, Nadolol, Quinine, α- Methylionol, Phyllocladene, alcohols, acids, phenols and 2,6-dihydroxy benzoic acid were the most abundant antimicrobial agents in the barnyardgrass root exudates.