Effect of seed hardening on the seedling emergence and α-amylase activity in the grains of wheat and rice sown in dry soil
Effect of seed hardening on the seedling emergence and α-amylase activity in the grains of wheat and rice sown in dry soil
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DOI：
10.1626/jcs.71.220
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发表时间：
2002-06-01
影响因子：
--
通讯作者：
Kobata, T
中科院分区：
文献类型：
--
作者：
Andoh, H;Kobata, T
种子硬化、播种前润湿和重新干燥种子，可以提高在干燥土壤中播种的小麦和水稻的发芽率和出苗率。我们研究了种子硬化对种子水势（土壤吸水驱动力）以及α-淀粉酶（可溶性碳水化合物供应的关键酶）活性的影响。在小麦品种Norin-61中，播种时硬化种子中的水分和渗透势分别为-7.2和-12.3MPa，非硬化种子中分别为-4.8和-9.9MPa。然而，在水稻品种日本晴中，水和渗透势均未受到种子硬化的明显影响。在Norin-61和日本晴中，在干燥土壤中播种后12小时的硬化种子中，α-淀粉酶活性分别是未硬化种子的2.7和2.8倍。在其他几个日本品种和韩国本土品种中，通过硬化处理提高了干燥土壤中的出苗率和播种前的α-淀粉酶活性，并且播种前硬化种子的α-淀粉酶活性相当于未硬化种子的1.9倍和8.3倍。据推测，由于α-淀粉酶活性增加，可溶性碳水化合物供应增加，种子硬化，从而提高了干燥土壤中的发芽率和出苗率。然而，硬化处理并没有降低水稻种子的渗透势。硬化处理期间的再干燥可能使除α-淀粉酶之外的一些酶的活性保持在发芽前的水平，从而促进发芽。
Seed hardening, wetting and redrying of the seed before sowing, increases the rates of germination and seedling emergence of wheat and rice sown in dry soil. We examined the effect of the seed hardening on the water potential of seed, a driving force of water absorption from soil, and the activity of alpha-amylase, a key enzyme for soluble carbohydrate supply. In wheat variety Norin-61, the water and osmotic potentials at the time of sowing were -7.2 and -12.3 MPa., respectively, in the hardened seed, and was -4.8 and -9.9 MPa, respectively, in non-hardened seed. However, in rice variety Nipponbare, neither water nor osmotic potential was clearly affected by seed hardening. In hardened seeds, the activity of alpha-amylase at 12 hours after sowing in dry soil was 2.7 and 2.8 times as high as that in non-hardened seeds in both Norin-61 and Nipponbare, respectively, In several other Japanese varieties and Korean native varieties also, seedling emergence rate in dry soil and alpha-amylase activity before sowing were increased by hardening treatment, and alpha-amylase activity of hardened seeds before sowing was 1.9similar to8.3 times as high as that of non-hardened seeds. It was assumed that the rates of germination and seedling emergence in dry soil were increased by seed hardening through the increase of soluble carbohydrate supply owing to increased alpha-amylase activity. However, hardening treatment did not decrease osmotic potential of rice seed. Redrying during the hardening treatment may have kept the activities of some enzymes in addition to alpha-amylase at the levels just before germination, and thus promoted germination.