Nectar secretion pattern, removal effects, and breeding system of Ligaria cuneifolia (Loranthaceae)

Some aspects of the reproductive biology of Ligaria cuneifolia have been studied, addressing the following questions: (i) Are there temporal differences in the female and male functions? (ii) How do nectar composition, volume, concentration, and amount of sugar vary throughout the flower lifetime? (iii) How does the plant respond to nectar removal? (iv) What is the breeding system of this species? Flowers last 4 days. There is a predominance of the male function in the first days and of the female function in the last days. Chemical composition of nectar varies throughout the flower lifetime; there is a constant decrease in sucrose along with an increase in glucose. Nectar is secreted during nights, and every secretion period is followed by a cessation interval. After the final cessation, a period of active resorption follows. During the mostly male phase of the flower, nectar has more sucrose than hexose, its secretion is discontinuous, and nectar removal reduces the rate of nectar production. During the...