How storage circumstance alters the quality of seeds of Lallemantia iberica and Lallemantia royleana produced under maternal drought stress

Abstract

Seed production underpins the agricultural industry and is impacted by the maternal environment during maturation. In addition, inappropriate post-harvest storage conditions can affect seed quality, by accelerating viability loss and reducing seed longevity. The objective of this research was to investigate the impact of storage conditions on the germination and physiological and biochemical processes of seeds of Lallemantia iberica and L. royleana under drought stress. Seeds were matured under maternal plant irrigation regimes of 30% (I30) and 60% (I60) of soil available water depletion and subjected to different storage conditions: control, natural aging (NA), controlled deterioration (CD), elevated partial pressure of oxygen (EPPO), and elevated partial pressure of nitrogen (EPPN). Seeds of both species matured under water deficit I60 had enhanced germination index, unsaturated and saturated fatty acid contents, total soluble sugar, sucrose and starch contents, and α- and β-amylase activities. This treatment also resulted in reduced seed electrical conductivity (EC), hydrogen peroxide (H2O2), and malondialdehyde (MDA) concentrations. The different seed storage conditions had negative effects on germination index, storage compounds, and fatty acids, with the smaller and greater changes under NA and EPPO aging, respectively. During the different aging conditions, it was noted that L. iberica seeds showed greater deterioration compared to L. royleana seeds. In conclusion, post-harvest conditions impact seed quality, with mild stress of the maternal environment increasing the seed longevity of both Lallemantia species.