Assessment of seed quality in novel sexual tetraploid population of Paspalum notatum

MARTINEZ ERIC JAVIER; ZILLI ALEX LEONEL; ACUÑA CARLOS ALBERTO

Foz do Iguazu

Congreso; International Congress of Genetics; 2018

Paspalum notatum is a warm-season perennial grass native from America, used as forage species around the world. Despite of its numerous advantages as forage, its adoption has been limited mainly because of low and variable germination of seeds. Recently, a sexual synthetic tetraploid population (SSTP) has been generated by mean of crossing a few experimental sexual tetraploid genotypes (ESTG) and natural apomictic tetraploid genotypes (NATG), and recombining the sexual F1. The aim of this work was to characterize the SSTP, based on features of seed quality, and compare its performance with ESTG and NATG. Seed fertility was estimated, based on seed set under self- (SP) and open-pollination (OP). The weight of 1000 seeds (W1000), germination power (GP) at 21 d after sown and speed of germination (SG) 8 d after sown (SG= GP*GP8/100) were measured using the obtained seeds. Seed set was 18.1 (CV= 52%), 7.4 (124%) and 10.3 (102%) under SP and 32.1 (29%), 10.9 (96%) and 23.4 (46%) under OP for NATG, ESTG and SSTP, respectively. The NATG showed higher seed fertility under both pollination methods, whereas the SSTP showed higher open-fertility than the ESTG. The remaining variables did not show differences between pollination methods neither between groups of genotypes. Mean for W1000 was 3.58 g (18%), while for GP and SG were 29% (75%) and 6% (179%), respectively. The seed quality of the SSTP was similar to its ancestors; meanwhile open-fertility was intermediate. The high variability observed in the SSTP would be useful for breeding programs.