Streptomyces biocontrol suppresses Sugarcane mosaic virus in Egyptian genotypes

Egyptian researchers have identified a new isolate of Sugarcane mosaic virus (SCMV) and found that a preventive application of a Streptomyces-based biocontrol agent significantly suppresses the disease and improves sugar quality in sugarcane, with genotype EH128-2 showing the strongest resistance. The study, conducted during the 2024/2025 season, tested four sugarcane genotypes under four treatment regimens. Applying the Bio-Act treatment before virus inoculation was most effective, boosting sucrose content to 9.6%, purity to 75%, and sugar recovery to 8.8%, while also enhancing biochemical defenses like phenolic content and antioxidant enzyme activity. The Egyptian SCMV isolate showed 94.6-99.8% nucleotide identity with global isolates, most closely matching Iranian strains. Genotype EH128-2 demonstrated the lowest viral load and highest defense responses, making it a promising candidate for breeding programs, though field trials are needed to validate the biocontrol strategy's commercial viability.