Fusarium species substantially threaten wheat harvests, resulting in considerable losses. Applying chemical fungicides
to address fungal diseases may adversely affect the environment and human health. Therefore, the development of novel
environmentally sustainable fungicides is imperative. This work isolated fifteen Streptomyces (St) isolates from soil and
subsequently identified them using morphological, biochemical, and molecular techniques. Four St isolates (St1, St2, St3,
and St4) were chosen for their pectinase and antifungal activities as alternative fungicides against Fusarium clumorum
infection in wheat. The sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) electropherogram of four
Streptomyces bungoensis isolates exhibited 35.7% polymorphic protein bands. In contrast, discontinuous polyacrylamide
gel electrophoresis (DISC-PAGE) analysis of pectinase isozymes revealed seven bands with differing densities, of which
five polymorphic bands constituted 71.4%. Random amplified polymorphic deoxyribonucleic acid analysis by polymerase
chain reaction (RAPD-PCR) revealed polymorphism among four isolates by identifying eight polymorphic amplified DNA
fragments, representing 94% of the total. The St1, St3, and St4 isolates produced unique DNA fragments of 127, 575,
and 950 base pairs. The phylogenetic tree indicates that the four isolates are closely linked within a single group. The St4
was chosen for the in vivo greenhouse trial due to its antifungal properties, superior protein content, and pectinase activity. Administering St4 (100 µg/ml) diminished the pre-emergence of root rot disease by 87%; concurrently, it decreased
the incidence and severity of crown and root rot disease (CRD) by 81% and 90%, respectively. The Fusarium infection
decreased shoot weight by 33%, although root weight remained consistent with the control group. The grain yield rose by
10% in healthy wheat plants and did not impact FC-infected plants treated with Streptomyces. The weight of 1000 grains
rose by 40% relative to the control group. The St4 was established to regulate the levels of total chlorophyll, carotenoids,
and antioxidant content in wheat infected with F. clumorum. T |
