Biocontrol traits of plant growth suppressive arbuscular mycorrhizal fungi against root rot in tomato caused by Pythium aphanidermatum

Abstract

Arbuscular mycorrhizal (AM) fungi known to cause plant growth depressions in tomato were examined for their biocontrol effects against root rot caused by Pythium aphanidermatum. The main hypothesis was that plant growth suppressive AM fungi would elicit a defence response in the host plant reducing Pythium root rot development. To test this hypothesis a fully factorial experiment was performed with AM fungi (Glomus intraradices, G. mosseae, G. claroideum or nonmycorrhizal), Pythium (± P. aphanidermatum) and harvest (7 and 14 days after pathogen inoculation (dapi)) as the main factors. Two weeks after AM fungi inoculation, roots were challenged with P. aphanidermatum. Variables evaluated at each harvest were root colonization levels of the interacting fungi, plant growth responses, and expression of a plant pathogenesis related protein gene (PR-1). All of the tested AM fungi caused marked growth suppressions, but did not affect PR-1 gene expression or the phosphorous concentration in the host plant. Plants singly inoculated with P. aphanidermatum had an increased PR-1 expression and phosphorous concentration. Among the AM fungi included in the study only G. intraradices reduced the pathogen root infection level, measured both in terms of Pythium ELISA and by recovery on selective media and only at the first harvest. Likewise, P. aphanidermatum root infection reduced colonization levels of G. intraradices, but not that of the two other AM fungi. In conclusion, plant growth suppressive AM fungi may offer plant beneficial traits in terms of biocontrol of root cortical pathogens.

Interactions between arbuscular mycorrhizal fungi and Meloidogyne incognitain the ornamental plant Impatiens balsamina

“…In the present study both AMF inocula caused host growth suppressions in treatments with fertilization and without nematode inoculation, but provided clear biocontrol traits in terms of induced tolerance against root-knot nematodes. Similar biocontrol traits of plant growth suppressive AMF have been reported in tomato-Glomus symbioses (Larsen et al 2012).…”

Micorrización de Agave cupreata: Biocontrol de Fusarium oxysporum y promoción del crecimiento vegetal

“…Los HMA juegan un papel importante en el control de diversos fitopatógenos a través de mecanismos directos o indirectos (Jung et al, 2012). Mecanismos directos como la competencia por sitios de colonización (Cordier et al, 1998;Larsen et al, 2012;Hernández-Montiel et al, 2013;Reyes-Tena et al, 2016), cambios en la composición de exudados radicales (Scheffknecht et al, 2006;Ren et al, 2015) e indirectos como la resistencia inducida por la micorrización de los diferentes mecanismos de defensa vegetal (Jung et al, 2012;Cameron et al, 2013). Jaiti et al (2007) encontraron que plantas de palma datilera (Phoenix dactylifera) inoculadas con un consorcio nativo (Glomus sp., Sclerocystis sp., Acaulospora sp.…”

EFEKTIFITAS FUNGI MIKORIZA ARBUSKULAR TERHADAP PERTUMBUHAN KIHIANG ( Benth) DI PERSEMAIAN DAN LAPANGAN

“…Keuntungan yang didapatkan para praktisi (pelaksana) penghijauan kehutanan di lapangan apabila menggunakan FMA pada produksi bibit di pesemaian adalah bibit tanaman bermikoriza lebih sehat dan kokoh, waktu pembibitan yang lebih singkat (Irianto, 2015a), bibit mempunyai daya adaptif yang tinggi untuk ditanam pada lahan marginal (Setiadi, 2009), tingkat ketahanan bibit/tanaman yang tinggi terhadap penyakit patogen tular tanah (Hage-Ahmed et al, 2013, Larsen et al, 2012, et al, 2 et al, Ismail 013, Kobra 2009, meningkatkan biomassa tanaman (Binu et al, 2015), serta mengurangi jumlah pupuk yang digunakan pada saat pembibitan maupun penanaman di lapang.…”