Fusarium verticillioides induction of maize seed rot and its control

Abstract

Experimental evidence is lacking to demonstrate whether Fusarium verticillioides (synonym = Fusarium moniliforme J. Sheld.; teleomorph = Gibberella fujikuroi (Sawada) Ito in Ito & K. Kimura, mating population A) functions as a causative agent or an opportunistic invader in seed (caryopsis) rot of maize (Zea mays L.). Previous researchers have isolated this fungus, along with many other microorganisms, from seed collected in the field long after rot commenced. The current investigations used an isolate of F. verticillioides transformed with a selectable marker and a reporter gene to inoculate previously disinfected maize seed. Seed rot developed, and F. verticillioides containing the introduced genes was isolated from inoculated, but not noninoculated, seed. Efficacy of Plantpro-45, an agent with an iodine-based active ingredient (a.i.), was analyzed for controlling growth of F. verticillioides from conidia and inoculated maize seed. A solution containing <10 µg a.i./mL inhibited growth of conidia suspended for <30 s. Furthermore, seed rot was controlled without diminishing seedling survival at 10 mg a.i./kg maize seed. Thus, F. verticillioides can function as the causative agent of maize seed rot and can be suppressed and (or) controlled at the postinfection stage with Plantpro-45.Key words: mycotoxin, reporter gene, germination, iodine.

Efficacy of bacterial seed treatments for the control of Fusarium verticillioides in maize

“…Previous researchers determined that F. verticillioides can function as the causative agent of maize seed rot (Yates et al 2003). However, we found that all maize plants grown from seeds inoculated with F. verticillioides (10 7 spores ml -1 ) and with the BCAs, B. amyloliquefaciens (T3) and M. oleovorans (T4) at 10 9 CFU ml -1 , grew well and did not show symptoms of disease after 20 days of cultivation in pots.…”

An Interspecies Signaling System Mediated by Fusaric Acid Has Parallel Effects on Antifungal Metabolite Production by Pseudomonas protegens Strain Pf-5 and Antibiosis of Fusarium spp

“…include wilts, rots, cankers, and blights of numerous agronomic, horticultural, and forest plants grown in agricultural, landscape, and natural settings (19). F. verticillioides causes ear rot of maize and sorghum (20) and Pokkah Boeng disease of sugarcane (21). Members of the F. oxysporum species complex cause wilt diseases of more than one hundred plant species (19).…”

“…Diseases caused by these Fusarium spp. are difficult to control with existing fungicides or soil fumigants, and many agricultural plants lack resistance to them (20,22). To meet the need for alternative disease management strategies, scientists have turned to microorganisms that inhibit Fusarium spp.…”

Antifungal Acylcyclopentenediones from Fruiting Bodies of Hygrophorus chrysodon

“…In the upfield portion of the 1 H NMR spectrum of 1, the sp 3 methylene proton resonances comprised a broad signal at δ 1.20-1.30, integrating for 10H, a distorted triplet (J ) 7.0 Hz) for 2H at δ 2.81, a quintuplet (J ) 7.0 Hz) for 2H at δ 1.68, and a distorted quartet (J ) 7.0 Hz) for 2H at δ 2.07. A terminal double bond was identified by the signals from the three spin system at δ 5.86 (1H, ddt, J ) 17.2, 10.1, 7.0 Hz), 4.92 (1H, dtd, J ) 17.2, 1.8, 1.5 Hz), and 5.02 (1H, dtd, J ) 10.1, 1.8, 1.5 Hz), while two quaternary carbons at δ 183.3 and 104.7 in the 13 C NMR spectrum were attributed to an enol moiety.…”

“…To have larger amounts for biological tests, compound 2 was synthesized in 16% yield by condensation of 4-cyclopentene-1,3-dione with undecanoyl chloride in the presence of excess anhydrous AlCl 3 .…”