Effect of seed coat mucilage, temperature and photoperiod on germination of four Arabian Desert species

GAIROLA, SANJAY; MAHMOUD, TAMER; ALKETBI, ASMA MOHAMMED; SHABANA, HATEM AHMED ; CARÓN, M.M.; EL-KEBLAWY, ALI

BOTANY

NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS

Lugar: Otawa; Año: 2022

1916-2790

In this study, we assessed the effects of mucilage presence, thermoperiod, and photoperiod on seed germination percentage and germination velocity (mean germination time) of four Arabian desert species. We hypothesized that mucilage presence, thermoperiod, and photoperiod and their interaction would influence seed germination. Seeds with and without mucilage were germinated under different alternating temperature regimes of 15/25° C, 20/30 and 25/35° C, night/ day temperatures with a 12 h/0 h light/dark photoperiod. Results show that the incubation temperature affected the germination of all the studied species. Photoperiod significantly affected the germination of Boerhavia elegans, Salvia aegyptiaca, and Sporobolus ioclados, while the mucilage presence influenced the germination of only S. ioclados. The interaction between mucilage presence, temperature, and photoperiod significantly influenced the germination percentage of B. elegans and S. aegyptiaca. Neither removal of the mucilage nor light conditions affect the germination percentages of Sporobolus spicatus. However, the temperature affected the germination of S. spicatus. The germination of all the studied species was faster for demucilaged seeds. Ecologically, the mucilaginous seed coat is considered an important adaptation for dispersal as it anchors seeds on the ground, and holds water around the seed during the germination stage in the stressful arid deserts habitats.