Beta-aminobutyric acid-induced resistance in grapevine against downy mildew: involvement of pterostilbene

Abstract

BABA, a non-protein amino acid, was used to induce resistance in grapevine against downy mildew. BABA-induced resistance was observed in the susceptible cv. Chasselas as well as in the resistant cv. Solaris. Following BABA treatment, sporulation of Plasmopara viticola was strongly reduced and the accumulation of stilbenes increased with time following infection. Induction of trans-piceide, trans-resveratrol and, more importantly, of trans-ɛ-and trans-δ-viniferin and trans-pterostilbene was observed in BABA-primed Chasselas. On the other hand, induction of transresveratrol, trans δ-viniferin and trans-pterostilbene was observed in BABA-primed Solaris. The accumulation of stilbenes in BABA-primed Solaris was much higher than that found in BABA-primed Chasselas. Furthermore, BABA-treatment of Solaris led to a rapid increase in transcript levels of three genes involved in the phenylpropanoid pathway: phenylalanine ammonia lyase, cinnamate-4-hydroxylase and stilbene synthase. BABA-primed Chasselas showed increased transcript levels for cinnamate-4-hydroxylase and stilbene synthase. Here we show that pre-treatment of a susceptible grapevine cultivar with BABA prior to infection with P. viticola primed the accumulation of specific phytoalexins that are undetectable in non-BABA-primed plants. As a result, the susceptible cultivar became more resistant to downy mildew.

Thiamine modulates metabolism of the phenylpropanoid pathway leading to enhanced resistance to Plasmopara viticola in grapevine

“…viticola sporangia suspension (10 4 sporangia/ml). ( A ) Presence of fluorescent material (discontinued arrows) under autofluorescence corresponding to stilbenes [6], surrounding unbranched and degenerated hyphae (discontinued arrows) of P . viticola in the mesophyll of thiamine-treated plant leaves.…”

“…IR in grapevine against P . viticola is characterized by the generation of H 2 O 2 [4], enhanced expression of pathogenesis-related (PR) proteins with antimicrobial activity, such as chitinases and glucanases [4,5], phytoalexin production [6,7], and callose deposition [4,5]. …”

“…Phenylpropanoid pathway-derived defense responses such as the synthesis of flavonoids, lignin, stilbenes and phenols have been shown to be associated with β-aminobutyric acid (BABA)-IR to P . viticola in grapevine [5,6]. A marked expression of phenylpropanoid pathway-derived phytoalexins including different stilbenic forms has been also reported to be associated with IR to P .…”

“…The general phenylpropanoid metabolism generates an array of secondary metabolites, which are based on the few intermediates of the shikimate pathway as the core unit [6]. The more relevant Vitaceae phytoalexins comprise a group of molecules belonging to the stilbene family [13].…”

Whole genome wide expression profiles of Vitis amurensisgrape responding to downy mildew by using Solexa sequencing technology

“…Genetic and gene expression profiling studies have concluded that Rpv1 , NPR1 homologs, and PR protein encoding genes contribute to the function of DM resistance in grapevines [10-12]. Others factors, including the amino acid beta-aminobutyric acid [13], and the proteins beta-1, 3-Glucanase [14], stilbene synthase (STS) [15], phenylalanine ammonia lyase (PAL) [16], thaumatin-like proteins and chitinase [17] may also play an important role in DM resistance. Many attempts, including transgenic [18-21] and traditional breeding approaches [10,22,23], have been undertaken to introgress resistance into V. vinifera genotypes.…”