Peroxidase and α‐Amylase Activities in Relation to Germination of Dormant and Nondormant Wheat

Abstract

Germination capacity, and α‐amylase production in relation to the peroxidase and isoperoxidase activities in the grains of three varieties of wheat have been analysed and compared. A high percentage of germination and α‐amylase producation at 25°C are associated with low peroxidase activity of the isolated embryo. This correlation is lacking when the intact grain is considered. A 2‐day treatment at 4°C which further increases the percentage germination and enhances α‐amylase synthesis, lowers the activity of peroxidase in the embryos. A general decrease in activity of all the isoenzymes is observed. Based on the above data and on differences in the activity of the most cathodic isoperoxidasic bands, a hypothesis is put forward which suggests that a sufficiently low peroxidase activity and a minimum auxin level of the embryo are responsible for the onset of germination.

A comparative study of the changes of peroxidase patterns during wheat, rye, and triticale kernel maturation

“…The results of the present work on wheat, rye, and triticale clearly coincide in the general facts that peroxidase isozymatic patterns are different in different tissues or organs of kernels and adult plants (Asins et al 198 1;Benito and PCrez de la Vega 1979;Garcia et al 1982;McDonald and Smith 1972;Upadhya 1968) and that pattern changes depend upon the developmental stage of the organ (Asins et al 1982;Gaspar et al 1977;Hamill and Brewbaker 1969;Kruger andLaBerge 1974a, 1974 6). While the differences among organs are clearly due to the activity of different sets of genes, as Benito and PCrez de la Vega (1979), Asins et al Garcia et al (1982) demonstrated in wheat and rye kernels, the changes in peroxidase patterns of the same organ during kernel maturation could be explained by changes in isozyme levels (amount of activity) or by posttranscriptional modifications affecting very slightly the mobility in relation to isozyme of mature stage (Asins et al 1982).…”

“…For instance, it has been observed that different parts of cereal kernels, such as embryo and endospenn, show different peroxidase electrophoretic patterns in Triticum aestivum L. (Gaspar et al 1977;Benito and Perez de la Vega 1979), Triticum turgidum L. (Asins et al 1981), Secale cereale L. (Garcia et al 1982), and Triticale (unpublished). For instance, it has been observed that different parts of cereal kernels, such as embryo and endospenn, show different peroxidase electrophoretic patterns in Triticum aestivum L. (Gaspar et al 1977;Benito and Perez de la Vega 1979), Triticum turgidum L. (Asins et al 1981), Secale cereale L. (Garcia et al 1982), and Triticale (unpublished).…”