Plant defence responses in oilseed rape MINELESS plants after attack by the cabbage moth Mamestra brassicae

Abstract

HighlightThe larvae of Mamestra brassicae feed less and show reduced growth on plants with ablated myrosin cells, which raises questions about the role of defence cells in Brassicaceae plants.

Arabidopsis myrosinases link the glucosinolate-myrosinase system and the cuticle

“…In our previous studies with Brassica napus transgenic MINELESS plants, which are deficient in myrosinase activity, we showed that MINELESS seedlings accumulated higher levels of glucosinolates14. Likewise, in the present study, the levels of certain glucosinolates were observed to be different in leaves of WT and tgg single and double mutants (Figs 6 and 7).…”

“…This is in terms of their interactive effect relating to insect herbivores by extracting glucosinolates from the leaf surface91011, or glucosinolates possibly originating from deeper leaf layers, herbivores penetrating the wax layer and perceiving compounds like isothiocyanates in deeper layers or through stomata12. Glucosinolates are structurally diverse phytochemicals produced throughout the Brassicaceae, including Arabidopsis thaliana and Brassica crop species81314. They comprise one component of the dual glucosinolate-myrosinase system, in which myrosinase thioglucosidase (TGG) (EC 3.2.3.147) catalyses glucosinolate breakdown into various biologically active molecules upon tissue disruption or insect attack141516.…”

“…Glucosinolates are structurally diverse phytochemicals produced throughout the Brassicaceae, including Arabidopsis thaliana and Brassica crop species81314. They comprise one component of the dual glucosinolate-myrosinase system, in which myrosinase thioglucosidase (TGG) (EC 3.2.3.147) catalyses glucosinolate breakdown into various biologically active molecules upon tissue disruption or insect attack141516.…”

Mechanisms of plant-insect interaction

“…Atle Bone’s laboratory has previously used a novel technique to produce oilseed rape plants that lack myrosinase-containing myrosin cells, which are normally distributed throughout plant tissues ( Ahuja et al , 2011 ). In this volume, the paper by Ahuja et al (2015) describes a series of experiments in which MINELESS plants were used to dissect the role of glucosinolate breakdown products in plant resistance to the cabbage moth Mamestra brassicae . MINELESS plants exhibited negligible levels of myrosinase activity and had higher total glucosinolate concentrations in both the absence and the presence of M. brassicae larvae with altered abundance of individual glucosinolates.…”

Comparative transcriptome analysis provides insights of anti‐insect molecular mechanism of Cassia obtusifolia trypsin inhibitor against Pieris rapae

“…The major defense in Brassicaceae family was the glucosinolate–myrosinase system. When insect herbivores attack plant tissues, glucosinolates are hydrolyzed by the enzyme myrosinase into a variety of toxic products, which can deter further herbivory (Ahuja et al., ). Cassia obtusifolia (Caesalpinioideae, Leguminosae) is a nonhost plant of P. rapae , and an important herb commonly found in subtropical areas.…”