WATER RESPONSE OF HYGROCHASTIC SKELETONS OF TRUE ROSE OF JERICHO (ANASTATICA-HIEROCHUNTICA L)
WATER RESPONSE OF HYGROCHASTIC SKELETONS OF TRUE ROSE OF JERICHO (ANASTATICA-HIEROCHUNTICA L)
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DOI：
10.1007/bf00345108
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发表时间：
1978-01-01
期刊：
影响因子：
2.7
通讯作者：
ELLIS, M
中科院分区：
文献类型：
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作者：
FRIEDMAN, J;GUNDERMAN, N;ELLIS, M
A. hierochuntica的骨架和果实的形态及其对种子传播的调节作用，根据水分条件的观点进行了研究。在实验室条件下，干骨架吸水是一个快速的过程，只需几分钟。接着是骨骼卷曲的树枝慢慢张开。饱和骨架在约2 h内达到最大打开。当只有骨架的主根浸入水中时，也会发生水的吸附和随后的打开。这一过程也被原位灌注的完整骨骼所复制。响应于蒸发的骨架闭合最初是缓慢的，仅在60%的水从饱和骨架中损失后才获得树枝的明显卷曲。骨架的打开使大部分水果暴露在雨滴的力量下。事实上，没有自发开放的果实发生在大多数实验室程序的骨架浸泡表明，在自然界中发生2个连续的过程：骨架必须首先uncurl hygrochasticly，使雨滴可以有力地撞击在附属物的果实阀，从而导致种子释放的ombrohydrochory。在充足的降雨量下，第一个打开的果实是那些在外部果序;更大的降雨量将释放种子从内部果序的上部果实，然后，从基部的果实。果瓣与隔片的结合力是可变的，其强度与果实在骨骼上不同位置的不同结构有关。这确保了与降雨量相称的释放速度，并确保第一粒种子至少有最低限度的水。就植物的年龄而言，骨架种群的异质性进一步确保了在给定地区的扩散速度与降雨量成正比。
The hygrochastic apparatus in A. hierochuntica was investigated from the standpoint of morphology of the skeleton and fruit and its contribution to the regulation of seed dispersal in accordance with the water conditions. Water adsorption by the dry skeletons upon shoot immersion under laboratory conditions is a rapid process requiring only a few minutes. It is followed by a slow opening of the curled branches of the skeleton. Maximal opening is attained by the saturated skeletons in approximately 2 h. Adsorption of water and subsequent opening also occur when only the main root of the skeleton is immersed in water. The process was also duplicated by intact skeletons irrigated in situ. Skeleton closure in response to evaporation is initially slow, noticeable curling of the branches obtained only after 60% of the water is lost from the saturated skeletons. Opening of the skeleton exposes most of the fruits to the force of falling raindrops. The fact that no spontaneous opening of fruits occurred under most laboratory procedures of skeleton immersion suggests that in nature 2 successive processes occur: the skeletons must first uncurl hygrochasticly so that raindrops can impinge forcefully on the appendages of the fruit valves and thus cause seed release by ombrohydrochory. Under adequate rainfall, the 1st fruits to open are those at the outer infructescences; heavier rainfall will release seeds from the upper fruits of the inner infructescences, and later, from fruits at their bases. The force that binds the valves of the fruits to the septa is variable, its strength correlated with different structure of the fruits at different positions on the skeleton. This ensures a rate of speed release commensurate with the rainfall, and secures at least a mimimum of water for the 1st seeds. The heterogeneity of skeleton populations, insofar as age of the plants is concerned, further ensures that speed dispersal in a given area will be proportional to the amount of rainfall.