Recent advances in regeneration protocols from weeping lovegrass [Eragrostis curvula (Schrad.) Nees]

SOBANSKI MANFRED; MARTÍNEZ-MACÍAS FÉLIX; LUCIANI GABRIELA; ECHENIQUE VIVIANA

Buenos Aires, Bs As, Argentina

Simposio; The 6th Edition of The International Symposium on the Molecular Breeding of Forage and Turf (MBFT 2010); 2010

Weeping lovegrass [Eragrostis curvula (Schrad.) Nees] is a suitable candidate for forage and lignocellulosic biomass production in marginal areas due to its low management, fertilization and irrigation requirements. However, weeping lovegrass nutritional and biofuel qualities could be improved by decreasing lignin levels and/or modifying lignin composition. A continuous and homogenous explant supply and an efficient and robust plant regeneration protocol are the first and essential steps to achieve stable transformation and develop successful molecular breeding strategies. Therefore, we focused in developing a plant regeneration protocol from seed derived-calli with the objective of providing a permanent explant supply and improving plant regeneration efficiency to use them in further transformation experiments. First, we used a factorial design to compare two Murashige and Skoog media (MS1: MS supplemented with 2.0 mg L-1 2,4-D, and MS2: supplemented with 1.0 mg L-1 BAP and 3.0 mg L-1dicamba) and three weeping lovegrass cultivars (‘Tanganiyka’, ‘Kromdraii’ and ‘Don Pablo’). Seeds were germinated, small calli were formed and plantlets were regenerated after 75 days. Calli formation and plant regeneration rates were registered. Our results indicated that cv. ‘Tanganyika’ generated 52% callus and from these calli 25% regenerated in MS2 medium. Second, we used other factorial design to improve this regeneration rate by using the MS2 medium supplemented with different BAP and dicamba concentrations (0.25, 0.5, 1.0 mg L-1 BAP and 3.0 and 1.5 mg L-1dicamba). We obtained 58% plant regeneration in a MS2 medium supplemented with 1.5 mg L-1 dicamba and 0.25 mg L-1 BAP in the cv. ‘Tanganyika’. Therefore, this protocol provides and efficient and robust plant regeneration system that could be used in further stable transformation experiments of weeping lovegrass.