In situ PHENOTYPIC EXPRESSION OF AGRONOMIC AND MORPHOLOGICAL TRAITS IN POPULATIONS OF THE JALA LANDRACE

Abstract

In situ conservation of genetic diversity in maize (Zea mays L.) has been made for years by traditional farmers, through planting native populations, as is the case of the Jala landrace, whose preservation is threatened by urban growth and natural factors. The distinctive characteristics of this landrace, such as plant height and ear length, have become dimibished. The number of farmers who grow in situ population of the Jala landrace is low, and seed of this landrace is often exchanged among them. For these reasons, it is relevant to assess whether or not there is phenotypic variation among current, conserved populations of the Jala landrace in Jala, Nayarit, México, its place of origin and primary distribution. In situ morphological characterization of 18 Jala landrace populations and seven controls were evaluated in 2010 using a 5 x 5 Lattice design with two replications, at three environments within the Jala Valley. With the averages of variables through environments, a combined analysis of variance, Tukey’s mean comparison, principal component analysis (PCA) and cluster analysis (ADC) were performed. PCA defined that the most influential variables for explaining the observed variation were ear length, plant height and cob height. ACD defined three groups of populations, in which there was greater phenotypic similarity with most of the current populations. It is concluded that in the Jala maize landrace there is low phenotypic variation among current in situ conserved populations, with a presumably reduced and common genetic base.