In Vitro and in Field Response of Different Fungicides against Aspergillus flavus and Fusarium Species Causing Ear Rot Disease of Maize

Abstract

Aspergillus flavus, the main aflatoxin B1 producing fungal species, Fusarium graminearum, a deoxynivalenol producer, and the fumonisin-producing species F. proliferatum and F. verticillioides are the main toxigenic fungi (TF) that colonize maize. Several strategies are available to control TF and related mycotoxins, such as chemical control. However, there is poor knowledge on the efficacy of fungicides on maize plants since few molecules are registered. The sensitivity of F. graminearum, F. proliferatum, F. verticillioides, and A. flavus to eleven fungicides, selected based on their different modes of action, was evaluated in both in vitro assays and, after selection, in the field. In vitro, demethylation inhibitors (DMI) showed excellent performances, followed by thiophanate-methyl and folpet. Among the succinate dehydrogenase inhibitors (SDHI), isopyrazam showed a higher effectiveness against Fusarium species than boscalid, which was ineffective against Fusarium, like the phenyl-pyrrole fludioxonil. Furthermore, both SDHIs and fludioxonil were more active against A. flavus than Fusarium species. In field trials, prothioconazole and thiophanate-methyl were confirmed to be effective to reduce F. graminearum (52% and 48%) and F. proliferatum contamination (44% and 27%). On the other hand, prothioconazole and boscalid could reduce A. flavus contamination at values of 75% and 56%, respectively.

Natural toxigenic fungal and mycotoxin occurrence in maize hybrids

“…These fungal species produce secondary metabolites (mycotoxins) which cause adverse effects on animal and human health, and economic losses. In particular, species from genera Aspergillus and Fusarium, causers of ear rot, cause serious risk of mycotoxin accumulation in maize (Masiello et al, 2019). Recently, aflatoxins, which are secondary metabolites produced by Aspergillus flavus Link and A. parasiticus Speare have been isolated in high levels on the maize grains in Serbia (Kos et al, 2018;Obradović et al, 2018).…”

“…In particular, species from genera Aspergillus and Fusarium, causers of ear rot, cause serious risk of mycotoxin accumulation in maize (Masiello et al, 2019). Recently, aflatoxins, which are secondary metabolites produced by Aspergillus flavus Link and A. parasiticus Speare have been isolated in high levels on the maize grains in Serbia (Kos et al, 2018;Obradović et al, 2018). Also, mycotoxins such as type B trichothecenes (deoxynivalenol) and zearalenone produced primarily of Fusarium graminearum Schwabe and fumonisins produced mainly of F. verticillioides (Sacc.)…”

Plasma‐assisted deposition of fungicide containing coatings for encapsulation and protection of maize seeds

“…Moreover, this agronomic practice can contribute to reduce further chemical treatments, thus reducing also the impact on environment and farmer health. Several molecules are active against F. graminearum , especially de methylation inhibitor (DMI) fungicides, that result very effective even at low doses . Among DMI fungicides, prothioconazole has been proved to have the best performance .…”

“…Several molecules are active against F. graminearum , especially de methylation inhibitor (DMI) fungicides, that result very effective even at low doses . Among DMI fungicides, prothioconazole has been proved to have the best performance . In spite of its efficacy, though, the increasing need to reduce the impact of chemicals in the agricultural practices requires a continuous improvement of control strategies for better environmentally friendly approaches.…”

“…[14][15][16] Among DMI fungicides, prothioconazole has been proved to have the best performance. [13] In spite of its efficacy, though, the increasing need to reduce the impact of chemicals in the agricultural practices requires a continuous improvement of control strategies for better environmentally friendly approaches.…”