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Selaginella Reproduction, Seed Habit, and Life Cycle
Vegetative and sexual methods.
VEGETATIVE REPRODUCTION:
Fragmentation: In S. rupestris, the trailing branches of the stem develop adventitious roots, that separate from the parent plant and grow into new sporo­phyte.
Tubers: Formation has been reported in S. chrysocaulos, S. chrysorhizos, dormant buds (S. chrysocaulis).
Bulbils: dormant buds produced in aerial branches, while tubers may be aerial or underground.
REPRODUCTION BY SPORES:
Numerous haploid spores are produced in the sporangium
The sporangium are located in the sporophylls and the sporophylls are com­pactly arranged to form cones or strobili.
STROBILUS
Generally strobili occur terminally on side branches, but in some species (e.g., S. patula and S. cuspidate produces a shoot with sporophylls and foliage leaves in alternate segments along the axis.
Selaginella is heterosporous and, therefore, sporangia are of two types viz., microsporangia and megasporangia.
The sporophylls associated with these two types of sporangia are designated as microsporophylls and megasporophylls respectively.