Dierking Emily C, Bilyeu Kristin D
University of Missouri-Columbia, Division of Plant Sciences, 110 Waters Hall, Columbia, MO 65211, USA.
USDA-ARS, Plant Genetics Research Unit, 110 Waters Hall, Columbia, MO 65211, USA.
J Plant Physiol. 2009 Aug 15;166(12):1329-1335. doi: 10.1016/j.jplph.2009.01.008. Epub 2009 Mar 14.
Raffinose family oligosaccharides (RFOs), which include raffinose and stachyose, are thought to be an important source of energy during seed germination. In contrast to their potential for promoting germination, RFOs represent anti-nutritional units for monogastric animals when consumed as a component of feed. The exact role for RFOs during soybean seed development and germination has not been experimentally determined; but it has been hypothesized that RFOs are required for successful germination. Previously, inhibition of RFO breakdown during imbibition and germination was shown to significantly delay germination in pea seeds. The objective of this study was to compare the germination potential for soybean seeds with either wild-type (WT) or low RFO levels and to examine the role of RFO breakdown in germination of soybean seeds. There was no significant difference in germination between normal and low RFO soybean seeds when imbibed/germinated in water. Similar to the situation in pea, soybean seeds of wild-type carbohydrate composition experienced a delay in germination when treated with a chemical inhibitor of alpha-galactosidase activity (1-deoxygalactonojirimycin or DGJ) during imbibition. However, low RFO soybean seed germination was not significantly delayed or reduced when treated with DGJ. In contrast to the situation in pea, the inhibitor-induced germination delay in wild-type soybean seeds was not partially overcome by the addition of galactose or sucrose. We conclude that RFOs are not an essential source of energy during soybean seed germination.
棉子糖家族低聚糖(RFOs),包括棉子糖和水苏糖,被认为是种子萌发期间的重要能量来源。与它们促进萌发的潜力相反,当作为饲料成分被单胃动物食用时,RFOs是抗营养物质。RFOs在大豆种子发育和萌发过程中的具体作用尚未通过实验确定;但据推测,成功萌发需要RFOs。此前,已表明在吸胀和萌发期间抑制RFO分解会显著延迟豌豆种子的萌发。本研究的目的是比较野生型(WT)或低RFO水平的大豆种子的萌发潜力,并研究RFO分解在大豆种子萌发中的作用。当在水中吸胀/萌发时,正常RFO和低RFO大豆种子的萌发没有显著差异。与豌豆的情况类似,当在吸胀期间用α-半乳糖苷酶活性的化学抑制剂(1-脱氧半乳糖野尻霉素或DGJ)处理时,野生型碳水化合物组成的大豆种子萌发延迟。然而,用DGJ处理时,低RFO大豆种子的萌发没有显著延迟或降低。与豌豆的情况相反,添加半乳糖或蔗糖并不能部分克服抑制剂诱导的野生型大豆种子萌发延迟。我们得出结论,RFOs不是大豆种子萌发期间的必需能量来源。