Influence of the Seed Envelope and Growth Regulators Upon Seed Dormancy in Witchweed (Striga lutea Lour.)
Influence of the Seed Envelope and Growth Regulators Upon Seed Dormancy in Witchweed (Striga lutea Lour.)
复制标题
种子包膜和生长调节剂对金缕梅种子休眠的影响（Striga utea Lour.）
DOI：
10.1093/oxfordjournals.aob.a084631
复制
发表时间：
1972
期刊：
影响因子：
--
通讯作者：
G. H. Egley
中科院分区：
文献类型：
--
作者：
G. H. Egley
被子植物寄生虫、巫草（Striga utea Lour.）的种子通常发芽很差或根本不发芽，除非经过充分预处理并暴露于从植物根部分泌物中获得的发芽刺激剂。在某些条件下，在没有刺激剂的情况下，种子包膜的划痕促进了发芽。对于经过充分（两周）预处理的种子，在根端切开或刺穿糊粉层可诱导典型的发芽。种子上其他地方的糊粉层被刺破，很少或根本不发芽。在种子的子叶末端或中心切开糊粉层会诱导非典型发芽，其中胚根伸长但没有穿透胚根上的完整包膜。无论种子划伤的位置如何，在氧气中孵育都不会促进发芽。百分之十的二氧化碳会降低穿孔种子的发芽率。当在胚根上划伤并在空气、氮气、黑暗或光中培养时，种子发芽同样良好。用硫酸进行短暂处理也能诱导发芽。刺激酸处理对糊粉层的软化作用在 6 小时后首次显现出来，并且仅发生在种子的根端。吲哚-3基-乙酸抑制松土和未松土种子的发芽，而乙烯刺激松土种子的发芽。赤霉酸（GAS）对未刮伤的种子没有明显影响，但促进了刮伤的种子的发芽。当用发芽刺激剂、乙烯、GAS 或硫酸处理时，预处理不充分（1 天）或过度（12 至 16 周）的种子发芽不良或根本不发芽。有些种子在胚根处进行翻耕时发芽缓慢，但发芽率和发芽总数均低于预处理2周的翻耕种子。添加刺激剂、乙烯或气体，加速了已松土但预处理不充分的种子的发芽率。在测试的处理中，只有 GA3 增加了过度预处理的划痕种子的缓慢发芽。结果表明糊粉层抑制胚根伸长。胚根上的划痕消除了限制并允许胚根出现。然而，根伸长的能力，受种子预处理时间和外源刺激剂、GA3或乙烯的影响，决定了划伤的种子是否发芽。
Seed of the angiospermous parasite, witchweed ( Striga lutea Lour.), normally germinate poorly or not at all unless adequately pretreated and exposed to a germination stimulant which is obtained from plant root exudates. Under certain conditions, scarification of the seed envelope promoted germination in the absence of the stimulant. With adequately (2-week) pretreated seed, a cut or puncture through the aleurone at the radicular end induced typical germination. A puncture through the aleurone elsewhere on the seed induced little or no germination. A cut through the aleurone at the cotyledon end or centre of the seed induced atypical germination in which the radicle elongated but did not penetrate the intact envelope over the radicle. Incubation in oxygen did not promote germination regardless of the site of seed scarification. Ten per cent carbon dioxide reduced the germination of punctured seed. Seed germinated equally well when scarified over the radicle and incubated in air, nitrogen, darkness, or light. Brief treatments with sulphuric acid also induced germination. The softening effect of stimulatory acid treatments upon the aleurone was first evident 6 h later and only occurred at the radicular end of the seed. Indol-3yl-acetic acid inhibited and ethylene stimulated germination of scarified and non-scarified seed. Gibberellic acid (GAS) had no apparent effect upon nonscarified seed but promoted germination of scarified seed. Inadequately (i-day) or excessively (12to 16-week) pretreated seed germinated poorly or not at all when treated with the germination stimulant, ethylene, GAS, or sulphuric acid. Some seed germinated slowly when scarified over the radicle, but the germination rates and totals were less than those of scarified seed pretreated for 2 weeks. Additions of stimulant, ethylene or GAS, accelerated the germination rates of scarified but inadequately pretreated seed. Of the treatments tested, only GA3 increased the slow germination of the excessively pretreated scarified seed. Results indicated that the aleurone restrained radicle elongation. Scarification over the radicle removed the restraint and permitted radicle emergence. However, the ability of the radicle to elongate, as influenced by time of seed pretreatment and exogenous stimulant, GA3 or ethylene, determined whether or not the scarified seed germinated.