Use of anthocyanin biosynthesis stimulatory genes as markers for the genetic transformation of haploid embryos and isolated microspores in wheat

Experiments were undertaken to study the use of anthocyanin biosynthesis st imulatory genes under the control of CaMV35S promoter and first intron of m aize alcohol dehydrogenase (Adh1), as marker genes for genetic transformati on of wheat haploid embryos and microspores by microprojectile bombardment. Transient expression was monitored for isolated microspore cultures of 1 a nd 8 days, after bombardment at 650 and 1100 psi. Anthocyanin expression in 1 day cultured microspores was only recovered at 650 psi, while a higher e xpression efficiency was obtained with 8 days old microspore culture at 110 0 psi. Experiments conducted on embryos show that total regeneration as wel l as albino and green plant regeneration of embryos were not affected by bo mbardment. 64.5% embryos presented spots and 6.2% of the regenerated plants were chimeric, with sectorial expression of anthocyanin on leaves. The com parison of GUS and anthocyanin expression was realized and we have shown th at anthocyanins are more reliable markers when compared with GUS. Besides b eing more practical, they give a better estimation of transformation proced ure efficiency. Results show that anthocyanin biosynthesis stimulatory gene s should be used as markers in haploid embryos and isolated microspores tra nsformation in wheat.