Transport and Retention of Phytophthora capsici Zoospores in Saturated Porous Media.

Autor: Jeon S, Krasnow CS, Kirby CK, Granke LL; Crop Protection Discovery, Dow AgroSciences , Indianapolis, Indiana 46268, United States., Hausbeck MK, Zhang W
Jazyk: angličtina
Zdroj: Environmental science & technology [Environ Sci Technol] 2016 Sep 06; Vol. 50 (17), pp. 9270-8. Date of Electronic Publication: 2016 Aug 24.
DOI: 10.1021/acs.est.6b01784
Abstrakt: Phytophthora capsici is an important plant pathogen capable of infecting several major vegetable crops. Water-induced P. capsici transport is considered to be a significant contributor to disease outbreaks and subsequent crop loss. However, little is known about factors controlling P. capsici zoospore transport in porous media, thus impeding our understanding of their environmental dispersal and development of filtration techniques for contaminated irrigation water. This study investigated the transport and retention of P. capsici zoospores in saturated columns packed with iron-oxide-coated sand (IOCS) or uncoated sand in Na(+) or Ca(2+) background solution at pH 7.7 ± 0.5 or 4.0 ± 0.3, in combination with XDLVO interaction energy calculations and microscopic visualizations. Significantly more encysted zoospores were retained in IOCS than in uncoated sand, and at pH 4.0 than at pH 7.7, which likely resulted from increased electrostatic attraction between zoospores and grain surface. At pH 7.7, up to 99% and 96% of the encysted zoospores were removed in IOCS and uncoated sand, respectively, due to a combination of strong surface attachment, pore straining, and adhesive interactions. Motile biflagellate zoospores were more readily transported than encysted zoospores, thus posing a greater dispersal and infection risk. This study has broad implications in environmental transport of Phytophthora zoospores in natural soils as well as in cost-effective engineered filtration systems.
Databáze: MEDLINE