title: Rhamnolipid Biosurfactant againstFusarium verticillioidesto Control Stalk and Ear Rot Disease of Maize.
abstract: Antifungal activity of rhamnolipids (RLs) has been widely studied against many plant pathogenic fungi, but not againstFusarium verticillioides, a major pathogen of maize (Zea maysL.).F. verticillioidescauses stalk and ear rot of maize or asymptomatically colonizes the plant and ears resulting in moderate to heavy crop loss throughout the world.F. verticillioidesproduces fumonisin mycotoxins, reported carcinogens, which makes the contaminated ears unsuitable for consumption. In this study, the RL produced using glucose as sole carbon source was characterized by FTIR and LCMS analyses and its antifungal activity againstF. verticillioideswas evaluatedin vitroon maize stalks and seeds. Further, the effect of RL on the mycelia ofF. verticillioideswas investigated by scanning electron microscopy which revealed visible damage to the mycelial structure as compared to control samples.In planta, treatment of maize seeds with a RL concentration of 50 mg l-1resulted in improved biomass and fruiting compared to those of healthy control plants and complete suppression of characteristic disease symptoms and colonization of maize byF. verticillioides. The study highlights the potential of RLs to be used for an effective biocontrol strategy against colonization of maize plant byF. verticillioides.
authors.affiliation: Environmental Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology Guwahati, India.
authors.forename: Siddhartha N
authors.initials: SN
authors.lastname: Borah
authors.affiliation: Environmental Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology Guwahati, India.
authors.forename: Debahuti
authors.initials: D
authors.lastname: Goswami
authors.affiliation: Department of Biotechnology, Gauhati University Guwahati, India.
authors.forename: Hridip K
authors.initials: HK
authors.lastname: Sarma
authors.affiliation: Institute of Microbial Technology Chandigarh, India.
authors.forename: Swaranjit S
authors.initials: SS
authors.lastname: Cameotra
authors.affiliation: Environmental Biotechnology Laboratory, Life Sciences Division, Institute of Advanced Study in Science and Technology Guwahati, India.
authors.forename: Suresh
authors.initials: S
authors.lastname: Deka
keywords: Fusarium verticillioides FS7; In planta activity; Pseudomonas aeruginosa SS14; Zea mays L.; biocontrol; rhamnolipid; scanning electron microscopy