Cytogenetic study of the ecotypic variety of maize from Calama, northern Chile

Abstract

The ecotypic variety of maize from Calama, known as “choclo calameño,” is cultivated in the surroundings of the highland city of Calama at an altitude of 2,400 m a.s.l. in northern Chile. However, factors such as urban expansion, the reduced flow of the Loa River, and the sale of agricultural land have drastically decreased its cultivation, placing this variety at risk of extinction. Currently, no cytogenetic information is available for this maize, which is essential for its conservation and genetic improvement. Therefore, the objective of this study was to characterize the structure and number of its chromosomes. Cytogenetic analysis determined a chromosome number of 2n = 20, with the following karyotypic formula: 5M + 4SM + 1SM/SAT. These results provide a fundamental basis for understanding aspects of its genome and applying this knowledge to the genetic improvement of the variety. Furthermore, the study highlights the importance of Calama maize as biological heritage and as an ecotypic resource with economic and social value.