2025 Volume 94 Issue 4 Pages 483-490
Although Basella alba and B. rubra have been used as annual leafy vegetables, ornamental plants, in dyes and in medicine for a long time in many countries, factors affecting seed germination in these species remain unclear. Therefore, in this study the effects of scarification treatment, temperature and light on seed germination were investigated in B. alba and B. rubra. In darkness, the germination percentage of scarified seeds was increased compared to non-scarified seeds in both species, suggesting that they show physical dormancy. Thermal optima for germination in B. alba and B. rubra were 25°C under dark conditions. In addition, light (white light) irradiation to seeds promoted germination, although they were able to germinate even if they were kept in darkness. It was also clarified in both species that the light quality of red (R) and far-red lights (FR) affected seed germination. Red light irradiation promoted seed germination, but far-red irradiation inhibited it. After far-red light irradiation for four days, the promotive effect of a red light on seed germination was reversed by a far-red light given immediately afterwards. Successive irradiation with R/FR/R promoted seed germination, but the subsequent FR irradiation cancelled the promotive effect of red light. Such reversible effects of red and fa-red light are typical in phytochrome-mediated seed germination in other species. Our results indicated that seeds of B. alba and B. rubra exhibit physical dormancy and light sensitive traits that are controlled by phytochrome(s), possibly phytochrome B.
