An experimental device for studying seed responses to naturally fluctuating temperature of surface soil under a constant water table
An experimental device for studying seed responses to naturally fluctuating temperature of surface soil under a constant water table
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研究恒定地下水位下种子对表层土壤自然波动温度反应的实验装置
DOI：
10.1046/j.1365-2435.1998.00210.x
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发表时间：
1998
影响因子：
5.2
通讯作者：
I. Washitani
中科院分区：
文献类型：
--
作者：
Sachiko Araki;S. Shiozawa;I. Washitani
1.设计了一种简单的实验装置，利用马里奥特虹吸式自动供水系统，在恒定的土壤水分条件下，使种子暴露在地表土壤温度的自然波动中。
2.除夏季干旱期间外，装置内5 cm深度的表层土壤温度及其波动与受自然水分波动影响的表层土壤温度基本一致。
3.在自然萌发季节，在装置内土壤0.5 cm处放置的紫苏种子萌发，而在5 cm或10 cm厚的枯枝落叶层以下放置的种子不能萌发。
4.在实验室条件下，8月份回收的未萌发种子不能在适宜的交变温度下萌发，除非暴露在先前的湿冷条件下，这表明诱导了二次休眠。因此，夏季较高的温度而不是夏季干旱或水分波动似乎是诱导休眠的原因，因为休眠是在充分水分的种子中诱导的。
1. A simple experimental device was designed, in which seeds can be exposed to natural fluctuation of surface soil temperature under a constant soil moisture condition maintained by an automatic water supply system based on the principle of a Mariotte siphon.
2. Except for the period during summer drought, surface soil temperature at a depth of 5 cm and its fluctuation within the device were largely similar to the temperature of the surface soil subjected to natural fluctuation of moisture.
3. The seeds of Persicaria lapathifolia placed at the depth of 0·5 cm in the soil within the device germinated during the natural germination season of the species, while the seeds placed at the depth of 5 cm or beneath the 10 cm-thick layer of litter failed to germinate.
4. The ungerminated seeds retrieved in August did not germinate at the favourable alternating temperature in the laboratory test unless exposed to previous moist chilling, suggesting the induction of secondary dormancy. Therefore, higher summer temperatures but not summer drought or moisture fluctuation seem to have been responsible for the dormancy induction, because the dormancy was induced in the fully hydrated seeds.