Genetic diversity in seven populations of Nicaraguan teosinte (Zea nicaraguensis Iltis et Benz) as estimated by microsatellite variation

Teosintes are the closest relatives to modern maize, Zea mays L. ssp. mays. They are wild grasses with a native distribution area from Mexico to Nicaragua and represent an important genetic resource. However, the genetic diversity of Nicaraguan teosinte (Zea nicaraguensis Iltis et Benz) has not yet been determined. This teosinte species has decreased in the last 25 years and now must be regarded as an endangered species. An analysis of the genetic diversity of Zea nicaraguensis was carried out in a total of 240 individuals from seven populations. Eleven Simple Sequences Repeat (SSR) primer pairs were used. A total of 42 alleles were found, the range of alleles per locus was 2-5 (mean 3.8) and the numbers of genotypes varied between primers. The primer Bnlg 1538 showed the highest value, with 45 genotypes through all populations. The genetic diversity observed (Ho) between all populations varied from 0.51 to 0.63, with an average of 0.563. One of the populations had as many as 40 alleles. Analysis of molecular variance (AMOVA) revealed that most of the variation was within population, at a significantly high level (P < 0.001). Rare alleles were detected in all populations, but unique alleles were only found in four populations. These results are highly relevant when developing conservation strategies and show that preserving populations in their natural habits is highly important.