Growth and Development of Horticultural Crops (1+1)

Reproductive development

• The output of the regulatory pathways which sense environmental and developmental signals results in the shoot apical meristem (SAM) entering the reproductive phase of growth. An inflorescence meristem is produced on which secondary floral meristems are borne; it is these which will develop to form the flowers. The inflorescence meristem may be determinate, eventually producing a terminal flower, or indeterminate, depending upon the species examined. It was recognized very early that reproductive development and reproductive organs appear to be modified forms of vegetative growth. Goethe in 1790 suggested that flowers were modified shoots and that the floral organs were modified leaves. Indeed the cell layers which can be distinguished in the vegetative SAM persist in the floral meristems, and genes such as CLV and STM which regulate the size of the vegetative meristem, fulfill a similar role in the floral meristem.