协同进化组知识库

Floral thermogenesis is a well-documented physiological process. However, floret (or inflorescence) development, thermogenesis and pollinator activity is rarely studied in association. In this study, the relationship between blooming, floral temperature and insect activity in Alocasia odora were observed. Based on the phenotypic characteristics of spathes and development of florets, four stages of blooming were categorized in A. odora: stage I (spathe closing), stage II (spathe unfolding, female florets receptive), stage III (male florets releasing pollen), and stage IV (spathe withering). Temperature analyses revealed that the appendix and male zone were the main thermogenic structures, but with different temporal patterns. The male zone showed a 3-day continuous episode of thermogenesis with three waves, to maintain an internal higher temperature, whereas the appendix showed a circadian rhythm of six cycles in 6 days with a duration of 6-7 h every day. Fruit flies were observed to mate, feed on the inflorescence, and enter the female zone to lay eggs when the spathe just opened at stage II. At the same time, the pollen that they carried from previous visits to another inflorescence was deposited on the stigma of female florets. The patterns of blooming and heating were closely tied to the activities of fruit flies. In particular, thermogenesis and behavior of flower-visiting insects were well synchronized and correlated during inflorescence development. Our results therefore suggest that floral thermogenesis plays an important role in successful reproduction.