Abstract

MARIN-MONTES, Iván Maryn et al. Morphological and molecular variation in 55 native tomato collections from Mexico. Rev. Chapingo Ser.Hortic [online]. 2016, vol.22, n.2, pp.117-132. ISSN 2007-4034.  https://doi.org/10.5154/r.rchsh.2016.03.008.

Recognizing native populations as genetic reservoirs necessitates their conservation, especially when referring to characters that are of interest for breeding new cultivars and in light of the limited genetic variation present in current commercial varieties. This research sought to evaluate the genetic variation in 55 collections of native tomato (Solanum lycopersicum L.) from nine states of Mexico, through their morphological and molecular characterization, and to create a strategy for their sustainable and efficient conservation. The collections were characterized morphologically under greenhouse conditions based on 62 descriptors used by the International Plant Genetic Resources Institute (IPGRI). Molecular characterization was performed using ISSR markers with 16 primers, which generated 118 amplified products, of which 81 allowed differentiating collections (68.7 % polymorphism). Multivariate analysis detected three groups based on morphological descriptors of leaves, flowers, stem and fruit, while the molecular characterization generated seven groups, coinciding by only 26.5 %. The origins of the collections had no association with the clusters. The presence of significant genetic variability in the native tomatoes was detected, so it is concluded that within the groups generated it is possible to identify materials with traits of interest for breeding. On the other hand, sustainable conservation of this genetic variability in seedbanks may be more efficient by requiring the safeguarding of 67 % of the collections studied.

Keywords : Solanum lycopersicum L.; molecular markers; morphological characters; ISSR.