Storage Potential of Seeds of Maize Collection Samples (Zea mays L.)

Abstract

The main condition for secure ex situ conservation of germplasm in plant gene banks is the necessity to preserve the viability of seeds, their physiological quality and to minimize aging rate. Loss of physiological quality of seeds results in yield decrease and low quality of seeds, loss of their uniformity and worsening of growth and development of plants as well as low resistance to environmental stresses. Production of seeds with high germinability is not sufficient per se. To ensure high storage potential of seeds it is necessary not only to obtain seed material with high viability but also to ensure its correct storage with the purpose of maintaining initial germinability. Therefore it is very important to determine storage potential of genotypes before placing them for long-term storage and to rank by this trait of valuable collection material. Use of test for accelerated aging of seeds (AA) allowed determination of genotypic features of maize collection accessions and their grouping by a potential capability of preservation of seed viability after the exposure to stress factors (increased temperature and humidity). With the help of morphophysiological (germination power and germinability of seeds, length of seedling rootlets, fresh and dry biomass of seedlings, electric conductivity of seeds) and biochemical (peroxidase activity) parameters of seeds and seedlings there has been determined storage potential of various genotypes of maize that is an important complex characteristics of collection accessions when they are placed for long-term storage in plant gene bank. Determination of storage potential allows revealing samples inappropriate for long-term storage and saving resources for conservation, as well as giving recommendations about reproduction of seed material and necessity to restore the viability of collection accessions using different physicochemical factors.