EFFECTS OF ANOXIA ON WHEAT SEEDLINGS .1. INTERACTION BETWEEN ANOXIA AND OTHER ENVIRONMENTAL-FACTORS
EFFECTS OF ANOXIA ON WHEAT SEEDLINGS .1. INTERACTION BETWEEN ANOXIA AND OTHER ENVIRONMENTAL-FACTORS
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DOI：
10.1093/jxb/42.11.1427
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发表时间：
1991-11-01
影响因子：
6.9
通讯作者：
GREENWAY, H
中科院分区：
文献类型：
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作者：
WATERS, I;KUIPER, PJC;GREENWAY, H
在根系首次暴露于0.016 ~ 0.06 mol m-3的O2浓度1 d后，对4-6 d龄的完整小麦幼苗施加缺氧。如果从缺氧返回到空气中发生伸长，则认为种子根的主轴尖端耐受缺氧，此后称为“伸长电位保留”。在缺氧条件下，完整幼苗根部的延伸电位比在0-5 mm切除的根尖上保留的时间更长，并提供50 mol m-3葡萄糖。完整幼苗在15℃条件下的伸长电位比在25℃条件下的延长，在pH 5.0和6.0条件下的延长电位比在pH 4.0条件下的延长。在外源性葡萄糖的存在下，这些处理之间的差异得以维持，葡萄糖的供应延长了所有缺氧处理中伸长电位的保留。在极低的O2浓度（0.006 ~ 0.01 mol m-3）下，伸长电位的保留时间远长于缺氧条件下；这是在pH 4.0时建立的。在pH值为6.0和15℃的缺氧条件下，对完整植株的根进行了实验，结果显示，缺氧抑制了79-97%的糖从芽和/或胚乳向根的运输。总体而言，研究结果表明：(i)田间涝渍期间缺氧的不利影响可能与其他环境因素相互作用；（ii）整合不同实验室获得的缺氧耐受性数据存在明显困难。
Anoxia was imposed on 4-6-d-old, intact wheat seedlings, after the roots had first been exposed for 1 d to O2 concentrations between 0.016 and 0.06 mol m-3. Apices of the main axis of the seminal roots were considered to have tolerated anoxia if elongation occurred after return from anoxia to air, hereafter called 'retention of elongation potential'. During anoxia, elongation potential was retained longer in roots of intact seedlings than in 0-5 mm excised root tips supplied with 50 mol m-3 glucose.In intact seedlings, elongation potential was retained longer at 15-degrees-C than at 25-degrees-C, and at pH 5.0 and 6.0 than at pH 4.0. These differences between treatments were maintained in the presence of exogenous glucose, and glucose supply prolonged the retention of elongation potential in all anoxic treatments.Elongation potential was retained much longer at very low O2 concentrations (0.006 to 0.01 mol m-3) than under anoxia; this was established at pH 4.0.Anoxia inhibited the transport of sugars from the shoots and/or endosperm to the root by 79-97%, as assessed from experiments with roots of intact plants exposed to anoxia at pH 6.0 and 15-degrees-C.Overall, the results demonstrate: (i) that the occurrence of adverse effects of anoxia during waterlogging in the field may interact with other environmental factors and (ii) that there are pronounced difficulties integrating data on tolerance to anoxia obtained in different laboratories.