GENETIC DIVERSITY IN NATURAL POPULATIONS OF PASPALUM INTERMEDIUM MUNRO EX MORONG &BRITTON

HOJSGAARD, DIEGO; ACUÑA C.A.; SCHEDLER M.; BRUGNOLI E.A.; ANA I. HONFI; KARUNARATHNE P.; ZILLI A.L.; MARTINEZ E.J.

FOZ DO IGUAZU

Congreso; 2018 INTERNATIONAL CONGRESS OF GENETICS; 2018

INTERNATIONAL FEDERATION OF GENETICS, SOCIEDADE BRASILERA DE GENETICA, ASOCIACION LATINOAMERICANA DE GENETICA

Paspalum intermedium is a grass native from South America with 2x sexual and 4x facultative apomictic individuals. The aim of this study was to estimate the genetic diversity in 4x P. intermedium natural populations. Five populations of 14 to 19 individuals were evaluated by ISSR (Inter Simple Sequence Repeats) markers. Intra-and inter-population diversity were estimated by percentage of polymorphic loci (PPL), number of genotypes, Shannon Index, genetic distance, and analysis of molecular variance (AMOVA). A total of 90 ISSR markers were analyzed and thePPL was 0 for two populations, 1.1, 2.2 and 5.5% for the other three. The number of genotypes indicated that there are two uniclonal populations, a population with 2 genotypes (represented by 2 and 16 individuals), and another population with 2 genotypes (6 and 13 individuals) and a population with 5 genotypes (1, 1, 3, 5 and 8 individuals). The Shannon Index pointed out values from 0 to 0.6. Genetic distances between populations showed a rank from 0.11 to 0.24. The intraand inter-population AMOVA was 3 and 97%, respectively, with a significant value of 0.96 ?PT between populations. These results indicate that most of the diversity is assigned among populations and that are expected for a species of facultative apomictic reproduction. Nevertheless the lack of variability in two 4x apomictic populations whit potential of sexualitycould be due there is no sexual events occurrence or there is a strong selection pressure against genotypes that may be caused by residual sexuality originating new clonal populations.