Plant Laboratory, Scuola Superiore Sant'Anna, Via Mariscoglio 34, 56124 Pisa, Italy.
Plant J. 2010 Aug;63(4):551-62. doi: 10.1111/j.1365-313X.2010.04262.x.
Soil flooding, which results in a decline in the availability of oxygen to submerged organs, negatively affects the growth and productivity of most crops. Although tomato (Solanum lycopersicum) is known for its sensitivity to waterlogging, its ability to produce adventitious roots (ARs) increases plant survival when the level of oxygen is decreased in the root zone. Ethylene entrapment by water may represent the first warning signal to the plant indicating waterlogging. We found that treatment with the ethylene biosynthesis inhibitor aminoethoxyvinylglycine (AVG) and the auxin transport inhibitor 1-naphthylphthalamic acid (NPA) resulted in a reduction of AR formation in waterlogged plants. We observed that ethylene, perceived by the Never Ripe receptor, stimulated auxin transport. In a process requiring the Diageotropica gene, auxin accumulation in the stem triggered additional ethylene synthesis, which further stimulated a flux of auxin towards to the flooded parts of the plant. Auxin accumulation in the base of the plant induces growth of pre-formed root initials. This response of tomato plants results in a new root system that is capable of replacing the original one when it has been damaged by submergence.
土壤淹水会导致淹没器官的氧气供应减少，从而对大多数作物的生长和生产力产生负面影响。尽管番茄（Solanum lycopersicum）以对水涝敏感而闻名，但当根区的氧气水平降低时，它产生不定根（AR）的能力会增加植物的存活率。乙烯被水捕获可能代表植物对水涝的第一个预警信号。我们发现，用乙烯生物合成抑制剂氨基乙氧基乙烯基甘氨酸（AVG）和生长素运输抑制剂 1-萘基邻氨甲酰苯甲酸（NPA）处理会导致水淹植物中 AR 形成减少。我们观察到，乙烯被 Never Ripe 受体感知后，会刺激生长素的运输。在需要 Diageotropica 基因的过程中，生长素在茎中的积累会引发额外的乙烯合成，这进一步刺激了生长素向植物淹没部分的流动。生长素在植物基部的积累会诱导预先形成的根原基的生长。番茄植株的这种反应会产生一个新的根系，当原根系因淹没而受损时，它能够取代原根系。
