Development of transgenic plants in jatropha with drought tolerance

Abstract

The seed oil of jatropha (Jatropha curcas L.) is a source of biodiesel fuel. Although jatropha can grow in semiarid lands unsuitable for the food production, its oil productivity in such conditions is unsatisfactory at present. Therefore, it is desirable to improve the oil productivity of jatropha even in semi-arid lands by enhancing its drought tolerance. Genetic engineering is promising to dramatically improve plant traits. Although we previously reported a transformation method, which involves wounding of tissue explants in order to increase the chance of Agrobacterium infection, for jatropha, it remains a challenge to enhance the shoot regeneration and root induction processes. Here, we report the generation of three kinds of transgenic jatropha plants in an attempt to improve their drought tolerance. The first one overexpresses the PPAT gene, which encodes an enzyme that catalyzes the CoA biosynthetic pathway; the second overexpresses the NF-YB gene, which encodes a subunit of the NF-Y transcription factor; and the last overexpresses the GSMT and DMT genes, which encode enzymes that catalyze production of glycine betaine. We also report a modified protocol that improves the efficiency of shoot regeneration and root induction in transgenic jatropha plantlets.