The role of abscisic acid and low temperature in chickpea (Cicer arietinum) cold tolerance.: II.: Effects on plasma membrane structure and function
The role of abscisic acid and low temperature in chickpea (Cicer arietinum) cold tolerance.: II.: Effects on plasma membrane structure and function
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DOI：
10.1093/jxb/erl120
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发表时间：
2006-11-01
影响因子：
6.9
通讯作者：
Dominy, Peter
中科院分区：
文献类型：
--
作者：
Bakht, Jehan;Bano, Asghari;Dominy, Peter
许多植物如鹰嘴豆的抗冻性可以通过暴露于低的非冻结温度和/或脱落酸（阿坝）的应用而增加，这一过程称为霜冻驯化。实验进行了研究超过14天的时间内丰富的质膜组分分离鹰嘴豆植物暴露于低温和喷施外源阿坝的反应。诱导50%叶细胞死亡（LT 50）的温度的测量和随后的统计分析表明，与许多植物一样，当与对照植物（20/7摄氏度;白天/夜晚）相比时，暴露于低温（5/-2摄氏度;白天/夜晚）诱导鹰嘴豆中显著水平（P < 0.05）的霜冻驯化。喷施外源阿坝也能显著提高植株的抗冻性（P < 0.05），但效果不如低温锻炼。预暴露于低温和阿坝预处理增加了质膜中脂肪酸去饱和的水平（测量为双键指数，DBI）。与未处理的对照植物相比，鹰嘴豆植物暴露于低温使DBI在第4天增加15%，在第14天增加19%。单独施用阿坝在任何时候都不会使DBI增加6%以上;两种处理一起施用的效果大于相加，与对照相比，在第14天诱导DBI增加27%。DBI与LT_（50）之间存在良好的相关性（P < 0.05），表明质膜中存在更多的不饱和脂质可以防止低温下的细胞溶解。无论是预暴露于低，非冻结温度和阿坝预处理引起的膜流动性的可测量的变化，但这些变化并不与LT 50的变化，这表明质膜的物理性质以外的流动性参与在鹰嘴豆霜冻驯化。
The frost hardiness of many plants such as chickpea can be increased by exposure to low non-freezing temperatures and/or the application of abscisic acid (ABA), a process known as frost acclimation. Experiments were conducted to study the response over a 14 d period of enriched plasma membrane fractions isolated from chickpea plants exposed to low temperature and sprayed with exogenous ABA. Measurement of the temperatures inducing 50% foliar cell death (LT50), and subsequent statistical analysis suggest that, like many plants, exposure to low temperatures (5/-2 degrees C; day/night) induces a significant level (P < 0.05) of frost acclimation in chickpea when compared with control plants (20/7 degrees C; day/night). Spraying plants with exogenous ABA also increased frost tolerance (P < 0.05), but was not as effective as low temperature-induced frost acclimation. Both pre-exposure to low temperatures and pre-treatment with ABA increased the levels of fatty acid desaturation in the plasma membrane (measured as the double bond index, DBI). Exposure of chickpea plants to low temperatures increased the DBI by 15% at day 4 and 19% at day 14 when compared with untreated control plants. Application of ABA alone did not increase the DBI by more than 6% at any time; the effects of both treatments applied together was more than additive, inducing a DBI increase of 27% at day 14 when compared with controls. There was a good correlation (P < 0.05) between the DBI and LT50, suggesting that the presence of more unsaturated lipid in the plasma membrane may prevent cell lysis at low temperatures. Both pre-exposure to low, non-freezing temperatures and pre-treatment with ABA induced measurable changes in membrane fluidity, but these changes did not correlate with changes in LT50, suggesting that physical properties of the plasma membrane other than fluidity are involved in frost acclimation in chickpea.