HERBICIDE-RESISTANT SUGARCANE (SACCHARUM-OFFICINARUM L.) PLANTS BY AGROBACTERIUM-MEDIATED TRANSFORMATION

The presence of undesirable plants in sugarcane (Saccharum officinarum L.) plantations reduces crop yields. Using genetic engineering as a c omplement for traditional breeding methods it is possible to introduce herbicide-resistant traits into Saccharum germplasm. Transgenic sugar cane plants resistant to phosphinothricine (PPT), the active compound of the commercial herbicide BASTA were generated by Agrobacterium tume faciens-mediated transformation. Meristematic sections of sugarcane we re treated with anti-necrotic compounds to minimize oxidative bursts a nd used as explants. Four transformation protocols were assessed and t he transformation frequencies reached 10-35%. The regeneration rate wa s high and did not appear to be affected by the transformation procedu re. Southern blot analysis of several transformed plants indicated the integration per genome of one or two intact copies of the bar gene wh ich encodes PPT acetyltransferase and confers resistance to BASTA. The levels of BASTA resistance were evaluated under greenhouse and small- plot conditions.