Indole derivatives enhance resistance against the rice blast fungus Magnaporthe oryzae

Abstract

In leaves pretreated with an indole derivative [indole-3-acetic acid (IAA) tryptamine, or tryptophan], blast lesion formation was suppressed compared to those treated with distilled water (DW) as a control. Phenylalanine ammonia-lyase (PAL) activity and PAL expression were significantly enhanced in the IAA-or tryptophanpretreated leaves, but not in tryptamine-pretreated leaves. This induction of resistance was inhibited by pretreatment with a PAL inhibitor, a-aminooxyacetic acid, in IAA-and in tryptophan-treated leaves, but not in tryptamine-treated leaves. This study strongly shows that the indole derivatives IAA tryptamine and tryptophan can enhance a disease resistance mechanism that is supported by different metabolic pathways.

Induced resistance in tomato plants against root knot nematode using biotic and abiotic inducers

“…In this respect (ElTayeb et al 2006;Gravel et al, 2007;Mandal et al, 2009;Sofy et al, 2014) they reported that, Indole acetic acid (IAA) is endogenous plant growth regulator and play an important role in many physiological processes under different biotic and abiotic stresses. Exogenous application of GA and IAA has been demonstrated to enhance plant resistance against pathogens by acting as potent inducer of systemic resistance (Ueno et al, 2011). The plant growth promoting rhizobacteria have been reported to improve plant growth either through direct stimulation by the synthesis of phytohormones (Xie et al, 1996) or by decreasing the effect of pathogens (Weller et al, 2002).…”

Effects of Salicylic Acid and Indole Acetic Acid Exogenous Applications on Induction of Faba Bean Resistance against Orobanche crenata

“…Moreover, an increase in the concentration of phenolic compounds and the activity of phenol metabolizing enzymes such as peroxidase (POX), polyphenol oxidase (PPO), and phenylalanine ammonia lyase (PAL) in response to salicylic acid (SA) activity were also reported ( Clarke et al, 2000 ; Thakur and Sohal, 2013 ). Other studies showed that indole acetic acid (IAA), a phytohormone auxin, which has been known to be a regulator of plant growth and development ever since its discovery, also shows an important role in the defense process against biotic stress (Al-Wakeel et al, 2013; Gravel et al, 2007 ; Ueno et al, 2011 ).…”

Studies on the expression of light-induced resistance of plants to the rice blast fungus

“…Blast lesion formation was significantly inhibited in these plants (Ueno et al 2004a(Ueno et al , 2011, suggesting that tryptamine pathway-related compounds (IAA, tryptamine, and tryptophan) can enhance a disease resistance mechanism that is supported by different metabolic pathways.…”