Marcadores enzimáticos e microssatélites para a caracterização de cultivares de milheto [Pennisetum glaucum (L.) R. Br.)]

Abstract

The demand for millet seeds has increased each year due to the expansion of direct planting areas and, thus, the investments for the development of new cultivars have become increasingly necessary. With the approval of the Cultivar Protection Law in 1997, in which is foreseen the right to charge for royalties by the cultivar breeders, the illegal commerce of seeds has become expressive, compromising the quality of the seeds, directly reflecting on the productivity. One of the means to insure genetic purity and protection rights is characterizing the cultivars with safe methods. The objective of this work was to characterize millet cultivars by means of enzyme and microsatellite markers and selecting microsatellite primers and enzymatic systems for cultivar identification. The analyzed cultivars were the following: ADR 300, ADR 500, ADR 7010, ADR 7020, ADR 8010, ANBS MC, ANM 17, ANM 30, IPA BULK 1BF, BN-1, BN-2 and BRS 1501. Seven enzymatic systems were tested: alcohol dehydrogenase (ADH), catalase (CAT), esterase (EST), glutamate oxaloacetate transaminase (GOT), malate dehydrogenase (MDH), isocitrate dehydrogenase (IDH) and acid phosphatase (ACP). A sufficient polymorphism for cultivar differentiation was not observed for enzymes ACP and CAT. For the microsatellite analysis we tested 123 pairs of primers of which 60 were selected. It was possible to identify millet cultivars by means of enzyme and microsatellite markers. Of the evaluated enzymatic systems, that of the esterase presented higher polymorphism for distinguishing the evaluated cultivars. It was possible to distinguish all millet cultivars used in this research with the primers PSMP2008, PSMP2045 and PSMP2056. For the microsatellite markers we observed polymorphism varying from 20 to 90%.