Host Range and Virulence of a Fungal Pathogen for Control of Giant Salvinia (Salvinia molesta) ()
Affiliation(s)
1USDA-ARS, Biological Control of Pests Research Unit, Stoneville, MS, USA.
2Crop Production Systems Research Unit, Stoneville, MS, USA.
3Louisiana Tech University, Ruston, LA, USA.
ABSTRACT
A
teleomorph of the fungus Botryosphaeria rhodina (Berkeley et Curtis) von Arx, (Br) was evaluated as a bioherbicide
for control of giant salvinia (Salvinia molesta D.S. Mitchell) under greenhouse conditions and
in small-scale field trials. We found that fungal mycelium was highly infective
and could be rapidly produced (48+ h) in soy flour-cornmeal liquid media
contained in shake flasks or fermenters. A dew period was not required to
achieve infection and mortality of inoculated plants. A surfactant (Silwet L-77, a
polyalkyleneoxide modified heptamethyl-trisiloxane) incorporated in the fungal
formulation was required for Br to infect and kill plants. Infection and
mortality occurred rapidly (within 48 h after treatment), and re-growth of
treated plants did not occur. In replicated field trials, Br controlled giant salvinia ~95%. Br also infected other plants, such as
common salvinia (S. minima Baker), and Azolla filiculoides Lam., as
determined in ongoing host range research. However, no symptomatology was observed on several
economically important crop species, such as rice (Oryza sativa L.), corn (Zea mays L.), and several woody species such as bald cypress (Taxodium distichum L.)
and loblolly pine (Pinus taeda L.) occurring in areas where giant
salvina occurs that would be subject to contact with releases of Br. These results suggest that
this teleomorph of Botryosphaeria rhodina has potential as a bioherbicide for controlling this
onerous aquatic weed.
Share and Cite:
Boyette, C. , Hoagland, R. , Higgenbotham, L. , Walker, H. , Young, J. and Stetina, K. (2021) Host Range and Virulence of a Fungal Pathogen for Control of Giant Salvinia (
Salvinia molesta).
American Journal of Plant Sciences,
12, 444-454. doi:
10.4236/ajps.2021.123029.