Development of a Large Set of Microsatellite Markers in Zapote Mamey (Pouteria sapota (Jacq.) H.E. Moore & Stearn) and Their Potential Use in the Study of the Species.

Renée Arias,Jaime Martínez-Castillo,Brian Scheffler,Nasib Blancarte-Jasso,Linda Ballard,Sheron Simpson,Brian Irish,Mary Duke,Victor Sobolev,Xiaofen Liu

doi:10.3390/molecules200611400

Abstract

Pouteria sapota is known for its edible fruits that contain unique carotenoids, as well as for its fungitoxic, anti-inflammatory and anti-oxidant activity. However, its genetics is mostly unknown, including aspects about its genetic diversity and domestication process. We did high-throughput sequencing of microsatellite-enriched libraries of P. sapota, generated 5223 contig DNA sequences, 1.8 Mbp, developed 368 microsatellites markers and tested them on 29 individuals from 10 populations (seven wild, three cultivated) from Mexico, its putative domestication center. Gene ontology BLAST analysis of the DNA sequences containing microsatellites showed potential association to physiological functions. Genetic diversity was slightly higher in cultivated than in the wild gene pool (HE = 0.41 and HE = 0.35, respectively), although modified Garza–Williamson Index and Bottleneck software showed evidence for a reduction in genetic diversity for the cultivated one. Neighbor Joining, 3D Principal Coordinates Analysis and assignment tests grouped most individuals according to their geographic origin but no clear separation was observed between wild or cultivated gene pools due to, perhaps, the existence of several admixed populations. The developed microsatellites have a great potential in genetic population and domestication studies of P. sapota but additional sampling will be necessary to better understand how the domestication process has impacted the genetic diversity of this fruit crop.

Highlights

The genus Pouteria Aublet (Sapotaceae) has 325 species, many of them known for their edible fruit and quality wood
Sequencing of P. sapota microsatellite-enriched libraries of genomic DNA resulted in 5223 assembled contigs with an average length of 345 bp, and an average reads per contig of 4.4
It is very important to know about how the domestication process has impacted the extent and distribution of the genetic diversity in vegetatively propagated fruit trees

Summary

Introduction

The genus Pouteria Aublet (Sapotaceae) has 325 species, many of them known for their edible fruit and quality wood. It is a non-monophyletic genus composed of at least three distinct evolutionary lineages [1,2]. Mexico is the most important producer of zapote mamey in the world, being Yucatan State the main producing area [7]. In this country, the traditional method of production is still in small orchards or by harvesting wild trees in the regions where they exist, whereas grafting is generally employed in small plantations or traditional home gardens [6]. Zapote mamey has been introduced as a fruit crop in South America, the Caribbean, Europe, Asia, Australia, and among other regions on the world [6]

Objectives

Results

Conclusion