Abstract

Information about seed source effects on germination and stress tolerance of the multipurpose exotic Prosopis juliflora (Sw.) DC. is scarce. Here, we investigate the influence of seed provenance on salinity tolerance and germination requirements of P. juliflora. Seeds collected from saline (SH) and nonsaline (SNH) habitats were treated with different NaCl concentrations (0–600 mM) and incubated in two photoperiods and three thermoperiod regimes. The results showed that tolerance of seeds from SH and NSH to salinity depended on thermoperiod, but not on photoperiod or interactions between photoperiod with both NaCl and thermoperiod. Germination of seeds from the two habitats did not differ significantly across thermoperiods in control and 200 mM NaCl. However, in 400 and 600 NaCl, germination was significantly greater for seeds from NSH than those from SH at lower thermoperiod in both light and darkness; whereas the reverse was true at higher temperatures in light. Seed germination of both habitat types was significantly lower at higher than at both lower and intermediate thermoperiods in all salt solutions, but the difference was more pronounced at higher salinities. Germination recovery failed in darkness at all photoperiod and thermoperiod regimes. Partial germination recovery happened only for seeds that failed to germinate in 400 mM NaCl in light and intermediate thermoperiod. Germination was significantly faster for seeds from SH than from NSH at higher salinities. The results emphasize the importance of considering the seed source for the restoration of salt-affected lands.

摘要

有关种子来源对多用途外来Prosopis juliflora (Sw.) DC发芽和胁迫耐受性影响的信息。稀缺。在这里，我们调查了种子来源对P. juliflora耐盐性和发芽要求的影响. 从盐水 (SH) 和非盐水 (SNH) 栖息地收集的种子用不同的 NaCl 浓度 (0-600 mM) 处理，并在两个光周期和三个热周期方案中孵育。结果表明，SH和NSH种子对盐分的耐受性取决于热周期，而不是光周期或光周期与NaCl和热周期之间的相互作用。来自两个栖息地的种子发芽在对照和 200 mM NaCl 的温度周期内没有显着差异。然而，在 400 和 600 NaCl 条件下，NSH 种子的萌发率在较低温度周期的光照和黑暗中均显着高于 SH 种子；而在光照较高的温度下，情况正好相反。在所有盐溶液中，两种生境类型的种子发芽率均显着低于较低和中等温度周期，但在较高盐度下差异更为明显。在所有光周期和热周期状态下，在黑暗中发芽恢复均失败。部分发芽恢复仅发生在 400 mM NaCl 中在轻度和中温期未能发芽的种子。在较高盐度下，SH 种子的萌发速度明显快于 NSH 种子。结果强调了考虑种子源恢复盐渍地的重要性。部分发芽恢复仅发生在 400 mM NaCl 中在轻度和中温期未能发芽的种子。在较高盐度下，SH 种子的萌发速度明显快于 NSH 种子。结果强调了考虑种子来源恢复盐渍地的重要性。部分发芽恢复仅发生在 400 mM NaCl 中在轻度和中温期未能发芽的种子。在较高盐度下，SH 种子的萌发速度明显快于 NSH 种子。结果强调了考虑种子源恢复盐渍地的重要性。