Esterases as Genetic Markers in Finger Millet

Different varieties of finger millet (Eleusine coracana Gaertn.) were screened for esterase activity colorimetrically and electrophoretically using 1-naphthyl acetate and acetylthiocholine chloride as substrates. The Indian brown seed coat variety (Purna), the Indian white seed coat variety (Hamsa), hybrids of these designated as HPB (brown) and HPW (white), African varieties (brown) and Indian-African hybrid varieties (brown) all exhibited 1-naphthyl acetate hydrolysing activity and showed 6,5,6,5,8 and 8 esterolytic bands respectively on gel electrophoresis. The white seed coat varieties, both parental (Hamsa) and hybrid (HPW), did not possess any acetylthiocholine chloride hydrolysing activity while all the brown seed coat varieties did, the African varieties having greater activities than Indian brown seed coat varieties. Thus, the demonstrable variation in esterase isozymic pattern and cholinester hydrolysing activity with the varieties tested provides a useful genetic marker for identifying different varieties of finger millet