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

0531298 - ÚEB 2021 RIV DE eng J - Journal Article
Hourston, J. E. - Pérez, M. - Gawthrop, F. - Richards, M. - Steinbrecher, T. - Leubner-Metzger, Gerhard
The effects of high oxygen partial pressure on vegetable Allium seeds with a short shelf-life.
Planta. Roč. 251, č. 6 (2020), č. článku 105. ISSN 0032-0935. E-ISSN 1432-2048
Institutional support: RVO:61389030
Keywords : Accelerated artificial ageing * Allium cepa x Allium fistulosum * Classical seed ageing * Controlled deterioration * Elevated partial pressure of oxygen (EPPO) * Salad onion * Seed longevity * Seed viability * Spring onion
OECD category: Plant sciences, botany
Impact factor: 4.116, year: 2020
Method of publishing: Open access
http://doi.org/10.1007/s00425-020-03398-y

Main conclusion: Storage at an 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 tenfold elevated partial pressure of oxygen (high pO2) at room temperature (22 ºC) in comparison to classical artificial ageing at elevated temperature (42 ºC). 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.
Permanent Link: http://hdl.handle.net/11104/0309991