Histologie du pédoncule inflorescentiel de Gerbera jamesonii

The inflorescential axis of Gerbera jamesonii is a determined one, not fully differentiated when growers cut the flowers. A region located 10 cm below the capitulum is very sensitive to “stem break”. Histology of this axis has been studied. Three different levels have been analysed; A, under the capitulum; B, 10 cm below the capitulum; C, halfway on the axis. Among the principal characteristics observed are a very important medullary parenchyma, a morphological endodermis, a half girdle of sclerenchyma under the capitulum and a full girdle of sclerenchyma in the mature zone. The distribution of the different tissues allows us to link the bending to the deficiency in supportive elements, typical of certain cultivars and of certain developmental stages.