摘要
(E)-b-Farnesene (EbF) synthase catalyses the production of EbF, which for many aphids is the main or only component of the alarm pheromone causing the repellence of aphids and also functions as a kairomone for aphids’ natural enemies. Many plants possess EbF synthase genes and can release EbF to repel aphids. In order to effectively recruit the plant-derived EbF synthase genes for aphid control, by using chloroplast transit peptide (CTP) of the small subunit of Rubisco (rbcS) from wheat (Triticum aestivum L.), we targeted AabFS1, an EbF synthase gene from sweet wormwood (Artemisia annua L.), to the chloroplast of tobacco to generate CTP t AabFS1 transgenic lines. The CTP t AabFS1 transgenic tobacco plants could emit EbF at a level up to 19.25 ng/day per g fresh tissues, 4–12 fold higher than the AabFS1 transgenic lines without chloroplast targeting. Furthermore, aphid/parasitoid behavioral bio-assays demonstrated that the CTP t AabFS1 transgenic tobacco showed enhanced repellence to green peach aphid (Myzus persicae) and attracted response of its parasitoid Diaeretiella rapae, thus affecting aphid infestation at two trophic levels. These data suggest that the chloroplast is an ideal subcellular compartment for metabolic engineering of plant-derived EbF synthase genes to generate a novel type of transgenic plant emitting an alarm pheromone for aphid control.
(E)-b-Farnesene (EbF) synthase catalyses the production of EbF, which for many aphids is the main or only component of the alarm pheromone causing the repellence of aphids and also functions as a kairomone for aphids’ natural enemies. Many plants possess EbF synthase genes and can release EbF to repel aphids. In order to effectively recruit the plant-derived EbF synthase genes for aphid control, by using chloroplast transit peptide (CTP) of the small subunit of Rubisco (rbcS) from wheat (Triticum aestivum L.), we targeted AabFS1, an EbF synthase gene from sweet wormwood (Artemisia annua L.), to the chloroplast of tobacco to generate CTP t AabFS1 transgenic lines. The CTP t AabFS1 transgenic tobacco plants could emit EbF at a level up to 19.25 ng/day per g fresh tissues, 4–12 fold higher than the AabFS1 transgenic lines without chloroplast targeting. Furthermore, aphid/parasitoid behavioral bio-assays demonstrated that the CTP t AabFS1 transgenic tobacco showed enhanced repellence to green peach aphid (Myzus persicae) and attracted response of its parasitoid Diaeretiella rapae, thus affecting aphid infestation at two trophic levels. These data suggest that the chloroplast is an ideal subcellular compartment for metabolic engineering of plant-derived EbF synthase genes to generate a novel type of transgenic plant emitting an alarm pheromone for aphid control.
基金
partly funded by the Research Initiative on Development of Insect Resistance Transgenic Wheat Plants supported by the Chinese Ministry of Agriculture (2014ZX0800201B)
Natural Science Foundation of China (31171618, 31371702)
Education Department of Henan Province (14A210004)
Nanyang Normal University (ZX2014061)
the Chinese State Key Laboratory for Biology of Plant Diseases and Insects (SKLOF201307)