The effect of the etched (et) mutation on the amylolytic enzyme activities in germinating kernels and seedlings of Zea mays

Abstract

The etched (et) mutation in maize causes distinct depressions and structural gaps in the endosperm and also gives rise to virescent seedlings, α- and β-Amylase activities were observed to be higher in et ⁺ et ⁺ kernels and seedlings as compared to that of the et et mutant. The total amylase and β-amylase trends during germination also differed between normal and mutant kernels and seedlings (it increases in the wildtype and decreases in et et). On the contrary, the overall α-amylase trend was found to be similar in both genotypes (slight decrease during germination). The native gel electrophoresis of crude enzyme extracts did not reveal any qualitative differences in α and β amylases during germination. The germinating et et kernels initially showed lower levels of starch compared with the wild type kernels, whereas no such difference was found at later stages of germination. It is concluded that et gene associated endosperm lesions lead to an impairment of starch degradation in germinating kernels resulting in virescent seedlings.