Tetrazolium Staining, Mitochondria, and Barley Quality

Dennis E. Briggs^1,3, Stanley M. Sole², and Philip Latham¹
¹ School of Biology, University of Birmingham, Edgbaston, Birmingham, U.K.
² Crisp Malting Group, Ltd., Norfolk, U.K. and author’s present address is 5, Sutton Road, Swaffham, Norfolk, PE37 7SN, U.K.
3 Corresponding author. Email: debriggs061@clara.co.uk
Author’s present address is 66 Sandhills Lane, Barnt Green, near Birmingham, B45 8NX. U.K

J. Inst. Brew. 115(1), 41–48, 2009 | VIEW ARTICLE

ABSTRACT
Triphenyl tetrazolium chloride (TTC) staining of individual isolated barley aleurone layers was carried out under aseptic conditions and the amount of formazan generated under a standardized incubation period was quantified. The nature of the tests minimized or excluded the influences of grain damage, ageing or contaminating microorganisms. Embryos from selected Triumph barley grains, having intensely or poorly staining aleurone layers, were grown on to maturity. Collected grain was analysed and embryos from the highest-staining progeny from the highstaining aleurone line and the lowest-staining progeny of the low-staining aleurone line were grown on to yield grain of the second selected generations. Aleurone layers of the high-staining line continued to stain intensely, respired strongly, and generated large amounts of α-amylase in response to gibberellic acid and embryos from these grains respired and grew vigorously, as did whole grains. In contrast, the aleurone layers of grains from the low-staining line continued to stain poorly and respired weakly, generated little α-amylase in response to gibberellic acid, the embryos respired slowly and lacked vigour and, like the whole grains, grew poorly. It is proposed that these results are the consequence of the selection procedure separating lines with superior and inferior mitochondria. If this apparently novel approach using TTC staining is confirmed as being valid, it opens a new way for plant breeders to select for more vigorous cereal lines.

Key words:
Barley, mitochondria, novel plant-breeding possibilities, tetrazolium chloride (TTC) staining, uniformity, vigour.