Induction of Defense Gene Expression and the Resistance of Date Palm to Fusarium oxysporum f. sp. Albedinis in Response to Alginate Extracted from Bifurcaria bifurcata

Abstract

In many African countries, the Bayoud is a common disease spread involving the fungus Fusarium oxusporum f. sp. albedinis (Foa). The induction of plant natural defenses through the use of seaweed polysaccharides to help plants against pathogens is currently a biological and ecological approach that is gaining more and more importance. In the present study, we used alginate, a natural polysaccharide extracted from a brown algae Bifurcaria bifurcata, to activate date palm defenses, which involve phenylalanine ammonia-lyase (PAL), a key enzyme of phenylpropanoid metabolism. The results obtained showed that at low concentration (1 g·L−1), alginate stimulated PAL activity in date palm roots 5 times more compared to the negative control (water-treated) after 24 h following treatment and 2.5 times more compared to the laminarin used as a positive stimulator of plant natural defenses (positive control of induction). Using qRT-PCR, the expression of a selection of genes involved in three different levels of defense mechanisms known to be involved in response to biotic stresses were investigated. The results showed that, generally, the PAL gene tested and the genes encoding enzymes involved in early oxidative events (SOD and LOX) were overexpressed in the alginate-treated plants compared to their levels in the positive and negative controls. POD and PR protein genes selected encoding β-(1,3)-glucanases and chitinases in this study did not show any significant difference between treatments; suggesting that other genes encoding POD and PR proteins that were not selected may be involved. After 17 weeks following the inoculation of the plants with the pathogen Foa, treatment with alginate reduced the mortality rate by up to 80% compared to the rate in control plants (non-elicited) and plants pretreated with laminarin, which agrees with the induction of defense gene expression and the stimulation of natural defenses in date palm with alginate after 24 h. These results open promising prospects for the use of alginate in agriculture as an inducer that triggers immunity of plants against telluric pathogens in general and of date palm against Fusarium oxysporum f. sp. albedinis in particular.

Ncbi: Generalidades Del Repositorio Y Breve Descripción De Recursos Aplicables Al Estudio De La Fitogenética

“…Recientemente, Bouissil et al (2022) hicieron uso de este tipo de repositorios para organizar perfiles de expresión genética derivados de factores de inducción de proteínas de defensa y resistencia de la palmera datilera a Fusarium oxysporum f. sp. albedinis, en respuesta a alginato extraído de Bifurcaria bifurcata.…”

Elicitor Activity of Low-Molecular-Weight Alginates Obtained by Oxidative Degradation of Alginates Extracted from Sargassum muticum and Cystoseira myriophylloides

“…This polysaccharide has been widely used in the food [ 5 ], pharmaceutical, biomedical [ 6 ], and industrial fields [ 7 ]. In addition, several studies have reported the use of alginate in agriculture to stimulate plant growth and development [ 8 , 9 ] and to induce plant resistance mechanisms [ 10 , 11 , 12 ].…”

“…Several studies have investigated some functional mechanisms of oligoalginates in plants [ 25 , 26 ]. Recently, tomato seedlings and date palm roots treated with oligoalginates from Bifurcaria bifurcata showed the induction of natural defenses by increasing PAL activity and the production of polyphenols [ 11 , 12 ]. This has been accompanied by the induction of gene expression and resistance to Fusarium oxysporum f. sp.…”

“…This has been accompanied by the induction of gene expression and resistance to Fusarium oxysporum f. sp. albedinis [ 12 ]. Further works have revealed the ability of alginate oligomers to overcome abiotic stress [ 23 , 26 , 27 ].…”

An Insight into All Tested Small Molecules against Fusarium oxysporum f. sp. Albedinis: A Comparative Review

“…Bayoud disease [1][2][3][4][5], caused by the telluric fungus pathogen Fusarium oxysporum f. sp. albedinis (F.o.a) [6][7][8][9], represents the leading dangerous agent of date palms cultivation, having killed more than 15 million Moroccan and Algerian date palm trees.…”