Annual Life Cycle and Floral Development of 'Sarah Bernhardt' Peony in Israel

Abstract

The life cycle and morphogenesis of the floral shoot of Paeonia lactiflora Pallas cv. Sarah Bernhardt were studied under Israeli conditions. The renewal buds for the following year originate on the underground crown, at the base of the annual stems. Bud emergence begins in early spring. Stems elongate rapidly and reach heights of 50-70 cm in 60-70 days. Flowering begins in April and continues until the end of May. After flowering, the leafy stems remain green until September-October, when the leaves senesce, and the peony plant enters the “rest” stage for 3-4 months. The new monocarpic shoot initiated in the renewal bud at the end of June with the formation of the first leaf primordia and continued to increase in size until February. During summer, the renewal buds remain vegetative. The apical meristem ceases leaf formation after senescence of the aboveground shoots in the fall. During September, the apical meristem of the renewal buds reaches the generative stage and achieves the form of a dome, but remains undifferentiated. In October, floral parts become visible. Floral differentiation is terminated at the beginning of December. Floral initiation and differentiation of peony do not require low temperatures. Morphological development and florogenesis were similar to other geophyte species with an annual thermoperiodic life cycle.