However, chemical pesticides are not always equally effective against B. Along with fungicides, crop rotation, antagonistic or growth promotion bacteria and fungi, as well as their metabolites with fungicidal or resistance-eliciting activity, and chemicals mimicking biogenic elicitors are used for wheat seed treatment to reduce FCR and CRR. The risk of plant rotting increases after sowing under unfavorable conditions when seeds sit long in the cool or wet heavy soil, hence pre-sowing seed treatment with fungicides is the primary tool for reduction of seedling damage.
Since FCR and CRR belong to seed-transmitted diseases, infection of seed significantly contributes to pre- or post-emergence death of young seedlings.
Helminthosporium sativum, teleomorph: Cochliobolus sativus) prevails in southern regions, these fungi often occur together, forming the Fusarium-Helminthosporium root rot pathogenic complex in the spring wheat rhizosphere, where the composition and proportion of the rot-inducing species vary depending on local climate, soil type and cropping systems.
is more typical for cooler wheat-growing areas, while CRR caused by Bipolaris sorokiniana (syn. Although FCR caused by several Fusarium spp. In Russia, Fusarium crown-foot-root rot (FCR) as well as common root rot (CRR) are damaging diseases wherever wheat and barley are grown, but generally FCR is of more concern because of fusariotoxins and association with scab of cereals. Root rots caused by soil fungi result in yield losses of various cereals including wheat, which is a crop of great economic importance for many grain-producing regions worldwide. PME-induced ion exchange response in cultured wheat cells, their increased survivability, and up-regulated expression of some defensins’ genes in PME-exposed seedlings allow the suggestion of the plant-mediated character of disease-controlling effect observed in field. Pre-sowing PME application on seeds of two spring wheat cultivars naturally infected with FCR and CRR provided the mitigation of both diseases under field conditions during four growing seasons (2013–2016). In vegetation experiments, reductions in the DON production were observed with doses of 0.5 and 1 mg/mL of PME. Pre-inoculation treatments of seeds with PME significantly decreased the incidence (from 30 to 40%) and severity (from 37 to 50%) of root rots on seedlings without any inhibition of the seed germination and potentiation of deoxynivalenol (DON), DON monoacetylated derivatives and zearalenon production in FCR agents. kiharae cells, particularly the extracellular alkalinization assay, as well as gene expression analysis in germinated wheat seeds were used. To elucidate mechanisms putatively underlying PME protective activity, tests with cultured Triticum aestivum and T. Plant-protecting effect of the purified mycelial extract (PME) was demonstrated in vegetation experiments using a rolled-towel assay and by small-plot field trials. sambucinum strain FS-94 that induces resistance to tomato wilt was shown by this study to be a source of non-fungitoxic wheat-protecting metabolites, which were contained in a mycelium extract purified by gel-chromatography and ultrafiltration.
An approach to manage seed-transmitted Fusarium crown-foot-root rot (FCR, Fusarium spp.) and common root rot (CRR, Bipolaris sorokiniana) on wheat, avoiding environmental risks of chemicals, is seed treatments with microbial metabolites.
0 kommentar(er)
