Abstract

Pineapple is one of the most important tropical fruits and therefore intensive genetic improvement programs are being carried out in many countries, including Cuba. Our research team has previously introduced the bar gene, along with chitinase and AP24 genes, into the pineapple genome. Herein, we report on the biochemical side effects of the herbicide FINALE (R) on these transgenic plantlets during hardening. Levels of aldehydes and chlorophylls, and peroxidase activity were recorded. The transformed clone studied here, not sprayed with FINALE (R), showed the following side effects because of transgenesis only. Levels of malondialdehyde, other aldehydes, chlorophyll b, and total chlorophyll pigments decreased. The most remarkable biochemical differences between transgenic and non-transgenic plantlets after application of FINALE (R) follow. Levels of malondialdehyde and other aldehydes in transgenic material were not decreased by FINALE (R), perhaps because these levels were already low as a result of transformation. FINALE (R) increased peroxidase activity in transgenic plantlets but such increase was higher in non-transgenic material. The herbicide increased contents of chlorophyll pigments (a, b, total) in transformed plantlets. However, as expected, non-transgenic plantlets decreased levels of chlorophylls (a, b, total) after application of FINALE (R). The genetic transformation of pineapple with the bar gene not only conferred resistance to the herbicide FINALE (R), but also promoted other biochemical changes.