Rapid and automated characterisation of seed genotype using Micrograd electrophoresis and pattern-matching software.

Abstract

New precast microgels are described for use in quickly identifying seed of cereal varieties by determining protein composition within an hour. For example, gliadin proteins are extracted from crushed wheat grain, wheatmeal or flour with ethylene glycol (centrifugation not necessary) and 5 microliters extract is applied to a Micrograd gel (3-15% gel gradient) for ten minutes' electrophoresis at 300 volts in sodium lactate buffer (pH 3.1). Alternatively, precast gels are available for SDS gel electrophoresis for examining a different aspect of grain composition as a means of identification. To further expedite identification, software packages have been developed to match the protein pattern for an unknown sample against those of authentic samples, thus to provide quick and definite identity, based on electrophoretic banding, densitometer scan, HPLC profile, multiple antibody reaction or RFLP pattern (PatMatch program). Furthermore, the program WhatWheat offers advice on the best combination of methods to use for a specific task of identification.