Inter-specific hybridation improves forage quality, salt tolerance and tannins levels in Lotus spp

ESCARAY FJ, F PAOLOCCI, P CARRASCO; S DEL VALLE; FL PIECKENSTAIN, OA RUIZ

San Miguel de Tucumán, Tucumán, Argentina

Congreso; XLV Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009

Sociedad Argentina de Investigaciones Bioquímicas

Lotus tenuis is a keystone species in cattle production of the Salado River Basin (Argentine). Its tolerance to marginal edaphic regions is well known, but its condensed tannins (CT) levels should be improved. By contrast, L. corniculatus has adequate CT levels. The CT are polyphenolic oligomers that, in adequate concentration, increase the forage value diminishing internal parasites, avoiding rumen bloat and increasing the “bypass protein”.With the aim to improve the forage quality, we obtained a hybrid between diploid population of L. corniculatus collected in the Albufera de Valencia (Spain) and selected genotypes of L. tenuis (Argentina). Hybrid status was confirmed by PCR amplification and sequencing of ITS. The lines obtained showed an average content of CT (6,2 mg CT/g MS) between parental lines. The analyses of the relative expression of nine genes of the biosynthetic pathway of CT permit their correlation with foliar CT content. In addition, hybrid plants had a better photosynthetic performance than L. tenuis under saline stress. Fresh and dry weights and the Na+, K+, Cl-, chlorophyll, anthocyanins and CT levels were also assessed. In resume, the hybrid obtained has a high agronomical potential and constitute a good material to analyze the biochemically and molecular regulation of CT biosynthetic pathway and abiotic tolerance traits in Lotus crops species