Plant & Animal Genomes XVI Conference

January 12-16, 2008
Town & Country Convention Center
San Diego, CA

Abolishing Aliphatic Glucosinolate Biosynthesis By RNAi In B. napus And Other Brassica Species

¹Genyi Li , ¹Zheng Liu , ¹Peter B. E. McVetty , ¹Fouad Daayf

  ¹ Department of Plant Science, University of Manitoba Winnipeg, Manitoba, R3T 2N2, Canada

When Brassica species is used as oilseed crops, reduced glucosinolate content in the seeds is essential for the improvement of meal quality. Aliphatic glucosinolates are the major glucosinolate components in seeds and their reduction commonly results in low content of total glucosinolates in seeds such as B. napus. Using the sequence of the Bo-GSL-ELONG in B. oleracea, two RNAi constructs were made to transform B. napus for silencing their corresponding genes and abolishing aliphatic glucosinolate biosynthesis. More than 100 transgenic plants were produced and crosses between transgenic B. napus, B. rapa and B. juncea were made. Glucosinolate analysis showed that most T₂ transgenic plants and F₁ plants had only trace amount of aliphatic glucosinolate content in leaves and some also had 80% reduction of aliphatic glucosinolate content in T₂ seeds. Interestingly, there was changed cotyledon glucosinolate content in F₁ plants of these crosses between the transgenic canola with trace amount of aliphatic glucosinolates and rapeseed with high content of glucosinolates, suggesting that seed glucosinolates are synthesized in embryos, not transferred from maternal tissues.