J. Plant Physiol. 160. 961 – 966 (2003)  Urban & Fischer Verlag http://www.urbanfischer.de/journals/jpp Uptake and distribution of sinigrin in microspore derived embryos of Brassica napus L. M. Cassim Mohamed Iqbal 1 *, Christian Möllers 2 1 Plant Reproductive Biology, Institute of Fundamental Studies, Hantana Road, Kandy, Sri Lanka 2 Institute ofAgronomy and Plant Breeding, Georg-August-Universität,Von Siebold Str. 8, D-37075 Göttingen, Germany Received January 10, 2002 · Accepted November 25, 2002 Summary In Brassica napus, glucosinolates are transported from all parts of the plant into the embryo during seed development. In this study we describe the uptake of the alkenyl glucosinolate sinigrin by microspore derived embryos from high and low glucosinolate genotypes. Microspore derived embryos develop completely isolated from maternal tissues unlike zygotic embryos, which contains glucosinolates transported into the embryo synthesised in the vegetative tissues. The sinigrin in the culture medium was almost completely absorbed by the embryos after three days of culture. The embryos of high and low glucosinolate genotypes were equally capable of absorbing sinigrin from the medium. A significant increase in different alkenyl glucosinolates following feeding of sinigrin suggests induction of biosynthetic enzymes in the embryos. Following excess feeding of sinigrin, we found a strong uptake against a concentration gradient and stable accumulation by the embryos. The glucosinolate was detected in single dissected cotyledons by a photometric test and by HPLC. This test could potentially be useful for screening mutants defective in glucosinolate uptake into the embryo. Key words: Brassica napus – glucosinolate uptake – microspore derived embryos – sinigrin Abbreviations: dw = dry weight Introduction Glucosinolates are secondary metabolites found in 15 fami- lies of Dicotyledons (Rodman 1991) present in all parts of the plant, their amounts varying in different plant tissues. In Bras- sica napus the embryo is the site of glucosinolate accumula- tion (Röbbelen and Thies 1980). A major objective in breed- * E-mail corresponding author: mcmif@hotmail.com ing has been to reduce glucosinolate content in seeds for use as animal feed. During seed development in B. napus, glucosinolates are transported into the seeds from other plant parts and stored in the embryo. Kondra and Stefansson (1970) found that the genotype of the maternal parent determines the seed glucosi- nolate content. To identify the source of glucosinolates in the seeds, Lein (1972) made reciprocal grafts of siliques between high and low glucosinolate containing B. napus genotypes 0176-1617/03/160/08-961 $ 15.00/0