Chitosan as Source for Pesticide Formulations

SEBASTIÁN D IPPÓLITO; JULIETA RENEÉ MENDIETA; MARÍA CECILIA TERRILE; CLAUDIA VIRGINIA TONÓN; ANDREA YAMILA MANSILLA; SILVANA LORENA COLMAN; LILIANA ALBERTENGO; MARÍA SUSANA RODRIGUEZ; CLAUDIA ANAHÍ CASALONGUE

Biological Activities and Application of Marine Polysaccharides

Intech

Año: 2017; p. 1 - 11

Late blight and wilt caused by the oomycete, Phytophthora infestans, and the fungus,Fusarium solani f. sp. eumartii, respectively, are severe diseases in Solanaceae cropsworldwide. Although traditional approaches to control plant diseases have mainly reliedon toxic chemical compounds, current studies are focused to identify more sustainableoptions. Finding alternatives, a low molecular weight chitosan (LMWCh) obtained frombiomass of Argentine Sea?s crustaceans was assayed. In an attempt to characterize theaction of LMWCh alone or in combination with the synthetic fungicide Mancozeb, theantimicrobial properties of LMWCh were assayed. In a side-by-side comparison withthe SYTOX Green nucleic acid stain and the nitric oxide?specific probe, diaminofluorescein‐FM diacetate (DAF-FM DA), yielded a similar tendency, revealing LMWChmediatedcell death. The efficacy of LMWCh, Mancozeb, and the mixture LMWCh?Mancozeb was in turn tested. A synergistic effect in the reduction of F. eumartii sporegermination was measured in the presence of subinhibitory dosis of 0.025 mg ml−1LMWCh and 0.008 mg ml−1 Mancozeb. This mixture was efficient to increase theeffectiveness of the single treatments in protecting against biotic stress judged by a drasticreduction of lesion area in P. infestans?inoculated tissues and activation of the potatodefense responses.