Reproductive Development of the Apex of Brachiaria decumbens Stapf

The development of Brachiaria decumbens tillers, as based onapex morphology, may be conveniently divided into six phases.These are the (1) vegetative, (2) raceme initiation, (3) spikeletinitiation, (4) spikelet differentiation, (5) inflorescenceexsertion and anthesis, and (6) seed maturation phases. Theonset of reproductive development is characterized by an increasein apex length and proceeds with the expansion of a bud in theaxil of the most recently initiated leaf primordium. This budgives rise to the first raceme and further racemes are formedin basipetal succession. Changes in apex morphology during thefirst four phases of development are described and illustratedwith scanning electron microscope and median longitudinal sectionphotomicrographs. Brachiaria decumbens, signal grass, apex morphology, SEM, median longitudinal sections, developmental phases