EVALUATION OF TRAITS RELATED TO SEED QUALITY IN ACROCERAS MACRUM (NILE GRASS)

SILVANA C. FERRARI USANDIZAGA; CARLOS A. ACUÑA; ELSA A. BRUGNOLI; LUIS GÁNDARA; CARLOS M. MAIDANA; NOELIA MAY PETROFF; JUAN P. BASUALDO

Pergamino

Congreso; 9TH INTERNATIONAL HERBAGE SEED CONFERENCE; 2017

INTERNATIONAL HERBAGE SEED GROUP

Acroceras macrum is a warm-season perennial grass native to tropical and subtropical regions of Africa. Its value as forage is due to the C3 photosynthetic pathway, offering higher nutritive value than C4 grasses. A. macrum is well adapted to wet or flooded Alfisols and vertisols of thenortheastern region of Argentina (NEA), where its use allows higher and more intense production in comparison to the natural grasslands. Its adoption on production systems is limited because the unavailability of commercial seed, although vegetative implantation through rhizomes and stolons can be achieved with excellent persistence. The tetraploid (2n = 4x = 36) cytotype of A. macrum available in Argentina presents wide genetic variability. The species is sexual, and it is possible to achieve viable seed by crosses between different 4x genotypes, with averages between 0 and 69%. Our objective was to study some features related to A. macrum seed quality. Sixteenfamilies (a total of 160 hybrids) obtained by crossing different 4x genotype were studied. Seeds were collected throughout the flowering period. Seed varied on size, maturation degree and pigmentation (brown) degree. The largest (2.8 mm) and heaviest seeds (2.6g / 1000 seeds) had germination (G) of 60% and a germinative energy (GE) of 30%, these were predominantly pigmented seeds. The lightest (1.2g / 1000 seeds) and smallest seed (2.2mm) had a G of 1.4% and an EG of 0%. Seeds with inmature aspect had G and EG of 0%. Significant differences in weight, seed filling and number of inflorescences produced per plant at peak flowering (mean 500-100 panicles) were found among families. Based on these results, we have initiated a breeding program based in selection against seed quality features.