Respiration and heat production by the inflorescence of Philodendron selloum Koch
Respiration and heat production by the inflorescence of Philodendron selloum Koch
复制标题
喜林芋花序的呼吸和产热
作者：
R. Seymour;G. Bartholomew;M. Barnhart
在2-d的开花序列中，产热的洋百合(Philodendron Sellom)的瓣片通过可逆地抑制呼吸产热来调节小范围内的最高温度(37-44°C)。这种反应保护花序和被引诱的昆虫免受热害。用氧气呼吸测量法测量的全肺产生的热量等于用梯度层量热法测量的热损失，这证实了氧气消耗的热等效性(20.4J·ml-1)。这也表明在产热过程中没有净磷酸化，产热是高呼吸速率的主要功能。不育雄花消耗约30mlg-1h-1，平均124gspadix产生约7W，以维持spadix与环境温度之间的30°C差。产热的能量主要存在于开花前的小花中。尽管呼吸频率很高，但产热作用是生殖过程中一个能量廉价的组成部分。
During a 2-d sequence of anthesis, the spadices of the thermogenic arum lily,Philodendron selloum, regulated maximum temperature within a small range (37–44°C) by reversible thermal inhibition of respiratory heat production. This response protects the inflorescence and the attracted insects from thermal damage. Heat production by whole spadices, measured by O2respirometry, equalled heat loss, measured by gradient layer calorimetry, which confirmed the heat equivalence of O2consumption (20.4 J ml-1). This also indicated that there was no net phosphorylation during thermogenesis, heat production being the primary function of high rates of respiration. The sterile male florets consumed about 30 ml g-1h-1and the average 124-g spadix produced about 7 W to maintain a 30°C difference between spadix and ambient temperature. Most of the energy for thermogenesis is present in the florets before anthesis. Despite high respiratory rates, thermogenesis is an energetically inexpensive component of the reproductive process.