Pomegranate Flower Receptivity Can Impact Both Fruit Set and Fruit Quality

Pomegranate (Punica granatum L.) is one of the oldest edible fruits and has been used for medicinal purposes since ancient time. Consumption of this juicy and flavorful fruit has increased dramatically in recent years. Yet, physiological studies on this unique crop are rather few, and information on floral biology is especially limited.  The objectives of the current study were to evaluate the performance of flowers pollinated at different flowering stages and to determine how flower receptivity impacts fruit set and quality.  Pomegranate flowers at the closed petal stage (Day 0) were emasculated and bagged.  Flowers were then hand pollinated on Days 0, 1, 2, 3, or 4, with developmental changes in flower morphology defined.  Subsequently, fruit set, fruit weight, and aril weight and number (the edible juice-containing sacs) were assessed. Results showed that flowers pollinated at younger stages not only attained higher fruit set, but also resulted in significantly larger fruits.  Fruits obtained from flowers pollinated on Day 1 were 56% larger and had 51% more aril weight than those from flowers pollinated on Day 4.  In pomegranate, early pollination not only increases fruit set, but has a marked effect on fruit quality.