IS IT POSSIBLE TO ASSOCIATE SEED DORMANCY WITH DOMESTICATION PROCESSES?

MARTÍNEZ, ANALÍA; BENECH ROBERTO; CAPPARELLI AYLEN; LEMA VERÓNICA; BARTOLI CARLOS

Corrientes

Otro; XXXI Reunión Argentina de Fisiología Vegetal; 2016

Asociación Argentina de Fisiología Vegetal

Domestication processes have led to a series of morphological and / or physiological changes in plant species, modifications that are due to both, cultural and natural selection forces. In this presentation seed dormancy as an indicator of domestication processes is discussed, using the association between Cucurbita maxima subsp. maxima, domesticated form known as ?criollo? pumpkin and Cucurbita maxima subsp. andreana, spontaneous form considered as its wild ancestor. In order to simulate possible crossbreeding occurred in the past, experimental crops and controlled crossinges between the two subspecies and among its hybrids (F1, F2) were experimentally characterized through various tests.Results indicate a loss of dormancy in seeds of domesticated subspecies and that the inhibition of germination in the wild subspecies is controlled by the seed coats. It was observed that embryos showed no germination difficulties in any genotype, but they do possess different sensitivity to growth regulators. It is concluded that the domestication processes resulted in changes at the physiological level by reducing the dormancy, a phenomena identified to be hormonally regulated  by the differential content of abscisic acid in seed coats and seeds as a whole.