血皮槭种子休眠机制研究

利用抑制物生物测定法和酸蚀技术研究了血皮槭种子休眠的原因。血皮槭种子吸水是一个非常缓慢的过程，在140 h以后种子含水量才能达到68%左右。酸蚀处理种子3 h，虽然没有加快种子的吸水速率，但能较好得使果皮变薄，也不影响种子的生活力。种子的各部位（果皮、种皮、子叶、胚根）均含有抑制物质，对小白菜种子的发芽率及胚根生长有很强的抑制作用，子叶各种处理水浸提液的抑制作用最强，果皮和种皮次之。血皮槭种子休眠主要由种壳机械障碍和种胚生理休眠两重因素导致，因此如何克服致密果壳而使激素能接触生理休眠的种胚是打破其种子休眠的关键技术。

Mechanisms of Seed Dormancy of Acer griseum

The internal and external causes of seed dormancy of Acer griseum were studied by inhibitor bioassay method and sulfuric acid treatment. Results showed that the water-absorption of A.griseum seeds was a slow process due to its thick woody pericarp. Water content of seeds of A.griseum reached only 68% after 140 h of water-absorption treatment. The sulfuric acid treatment for 3 h did not speed up the water-absorption, but made the percarp thinner without damaging seed viability. Inhibitory substances were detected in every part of the seed, including pericarp, seed coat, cotyledon and radicle. The cotyledon extracts had the stronger inhibitory effect on seed germination percentage and radicle growth than those from the pericarp and seed coat. The main reason for seed dormancy of A.griseum was physiological dormancy of seed embryo and physical obstacle of the pericarp. How to make the hormone reaching the seed embryo through the compact pericarp was the critical to break its dormancy quickly.