Transient expression of SbDhr2 and MeHNL in Gossypium hirsutum for herbivore deterrence assay with Spodoptera litura

Abstract

Background: Spodoptera litura (Lepidoptera: Noctuidae), commonly known as tobacco cutworm or cotton leafworm, is a polyphagous pest which causes considerable damage to cotton (Gossypium hirsutum) and other crops. Herbivore-induced defence response is activated in plants against chewing pests, in which plant secondary metabolites play an important role. Dhurrinase2 (SbDhr2), a cyanogenic β-glucosidase from Sorghum bicolor, is the key enzyme responsible for the hydrolysis of dhurrin (cyanogenic β-glucosidic substrate) to phydroxymandelonitrile. Hydroxynitrile lyase (MeHNL) from Mannihot esculanta catalyses the dissociation of cyanohydrins to hydrogen cyanide and corresponding carbonyl compound, both enzymes play a pivotal role in plant defence mechanism. Results: SbDhr2 and MeHNL genes were expressed individually and co-expressed transiently in cotton leaves. We examined the feeding response of S. litura to leaves in the choice assay. The S. litura population used in this study showed better feeding deterrence to leaves co-expressing both genes compared with the expression of an individual gene. Conclusion: Our results suggest that co-expression of SbDhr2 and MeHNL genes in cotton leaves demonstrate feeding deterrence to S. litura. Engineering cyanogenic pathway in aerial parts of cotton would be an additional defence strategy against generalist pests and can be enhanced against specialist pests.

Transgenic Cotton Plants Expressing Spidroin Gene Presenting Increased Fiber Quality

“…physiology, or improve fiber quality. The expression of many genes including GUS gene under the control of cotton A4 cellulose synthase promoter [21], cotton actin protein under the control of GhACT1 [21] GUS and GFP under the control of GhSCFP promoter [22] has been previously investigated. In this study, MaSp1 spider protein was specifically expressed in fibers and the whole plant.…”