ACUÑA Carlos Alberto
congresos y reuniones científicas
VARIABILITY FOR FERTILITY AND GERMINATION OF SEEDS IN THE SEXUAL TETRAPLOID GERMPLASM OF BAHIAGRASS
ALEX L. ZILLI; CARLOS A. ACUÑA; ERIC J. MARTÍNEZ
Congreso; 9TH INTERNATIONAL HERBAGE SEED CONFERENCE; 2017
INTERNATIONAL HERBAGE SEED GROUP
Bahiagrass (Paspalum notatum Flüggé) is a warm-season perennial grass native to South America and used as utility forage and turf around the world. It has two cytotypes, the diploid reproduce sexually and the tetraploid by apomixis. In spite of its numerous desirable traits for forage, its adoption has been limited mainly due to low germination levels. A few experimental sexual tetraploid genotypes (ESTG) have been generated. Recently a sexual synthetic tetraploid population (SSTP) was generated offering a wide genetic background for improvement. The objective of this work was to characterize the seed fertility and germination of the SSTP, and to compare this germplasm with the ESTG. Fertility was measured in 3 ESTG and in a sample of 28 individuals from the SSTP, based on seed set under self- (SP) and open-pollination (OP). Seeds obtained from OP were sowed on November under a complete randomized design with two replicates of 50 seed each one. Germination was calculated 21 d after sowing (G). Germinative energy (GE) was calculated based on germination 8 d (G8) after sowing (GE= GxG8/100). The SSTP showed 18.4% (Coefficient of variation (CV) = 54.2) and 30.6% (CV= 43.2) of seed set under SP and OP respectively, whereas ESTG showed 9.9% (CV= 58) and 22.5 % (CV= 41.1) of seed set under SPand OP respectively. The SSTP showed a G of 51.1% (CV= 43.2), significantly higher than the 26% (CV= 121) obtained in ESTG. The GE of the SSTP was 11.4% (CV= 115.2), significantly higher than the 4.5% (CV= 151.9) obtained in ESTG. There were not statistical differences between fertility of the two groups of genotypes; however, G and GE were improved on the SSTP with respect to ESTP. The high CV observed in all evaluated traits indicate high variation betweeN genotypes, which will be useful in breeding programs.