Efficacy of Multiple Silicon Root Applications on Wheat Resistance to Fusarium Head Blight

Abstract

Fusarium head blight (FHB), provoked by various Fusarium organisms, is among the main damages presenting in all Triticum spp.-cultivation regions. Silicon (Si) application of Triticum host as sustainable disease management has been shown to increase host resistance to FHB. It has been approved that Si rate does not reach 1.67 mM for the prohibition of host diseases. To test the effect of multiple Si root applications on enhancing wheat resistance in controlled environments, six Triticum lines with different resistances to head blight and inoculated with various Fusarium pathogens with varied aggressiveness were grown in growth chamber amended with 1.7 mM Si. The reduction in disease symptoms due to the effect of Si was expressed as FHB incidence (DI, Type I resistance), FHB severity (DS, Type II) and Area Under Disease Progressive Curve (AUDPC) evaluated on the basis of DI and DS. Overall, DI, DS and AUDPC calculated on the basis of DI and DS were reduced by 21.2%, 21.3%, 20.2% and 20.3% in Si treatments in comparing with -Si wheat plants. In comparing with non-Si applied hosts, Si application strongly enhanced all tested components of the wheat resistance, reinforcing the theory that the tested Si concentration is needed for the effective resistance to be manifested to FHB. Sensitive to moderately sensitive and sensitive lines could reduce FHB damage assessed by DI, DS and AUDPC calculated on the basis of DI and DS to a line exhibited a resistance with moderate level that were not applied with Si. Thus, our results showed that Si increased resistance measured by FHB incidence, FHB severity, AUDPC DI, and AUDPC DS on less resistant wheat lines to levels equivalent to those of lines exhibited a resistance with moderate level to FHB and not applied with Si, postulating theoretically that Si absorption by the roots is necessary to avoid negative impact of Fusarium infection. To our best knowledge, this study involved controlled-environmental tests presented the primary pathogenic evidence linked with the feeding of multiple Si applications in wheat hosts infected by Fusarium. Overall, our results lead to the conclusion that, when commercial wheat lines with elevated levels of resistance are not accessible to farmers in areas where soil is Si deficient, multiple Si fertilization through the root system is a promising component in the integrated host management to increase wheat resistance to FHB.