The effects of high oxygen partial pressure on vegetable Allium seeds with a short shelf-life

James Hourston, Marta Perez Suarez, Frances Gawthrop, Michael Richards, Tina Steinbrecher, Gerhard Leubner

Research output: Contribution to journalArticlepeer-review


Main Conclusion: Storage at elevated partial pressure of oxygen and classical artificial ageing cause a rapid loss of seed viability of short-lived vegetable seeds.
Abstract: Prolonging seed longevity during storage is of major importance for gene banks and the horticultural industry. Slowing down biochemical deterioration, including oxygen-dependent deterioration caused by oxidative processes can boost longevity. This can be affected by the seed structure and the oxygen permeability of seed coat layers. Classical artificial seed ageing assays are used to estimate seed 'shelf-life' by mimicking seed ageing via incubating seeds at elevated temperature and elevated relative humidity (causing elevated equilibrium seed moisture content). In this study we show that seed lots of vegetable Allium species are short-lived both during dry storage for several months and in seed ageing assays at elevated seed moisture levels. Micromorphological analysis of the Allium cepa x Allium fistulosum salad onion seed identified intact seed coat and endosperm layers. Allium seeds equilibrated at 70% relative humidity were used to investigate seed ageing at 10-fold elevated partial pressure of oxygen (high pO2) at room temperature (22ºC) in comparison to classical artificial ageing at elevated temperature (42ºC). Our results reveal that 30 days high pO2 treatment causes a rapid loss of seed viability which quantitatively corresponded to the seed viability loss observed by ~7 days classical artificial ageing. A similar number of normal seedlings develop from the germinating (viable) proportion of seeds in the population. Many long-lived seeds first exhibit a seed vigour loss, evident from a reduced germination speed, preceding the loss in seed viability. In contrast to this, seed ageing of our short-lived Allium vegetable seems to be characterised by a rapid loss in seed viability.
Original languageEnglish
Article number105
Pages (from-to)1-9
Number of pages9
Publication statusPublished - 16 May 2020

Cite this