The effect of shading during seed development on subsequent germination is largely unknown so far. In this study, two soybean seed production systems, monocropping (MC) and maize-soybean intercropping (IC), were employed. Compared to the MC soybean seeds, which received the normal light spectrum, the developing IC seeds were exposed to shade resulting from the taller neighboring maize plants. The IC seeds germinated faster than did the MC seeds, while there was no significant difference in the seed coat thickness. The soluble pro-anthocyanidin concentration in the IC seed coat was significantly lower than that in the MC seed coat, and the change of concentrations of several types of fatty acids in IC seeds was documented, findings which are consistent with the germination evidence. The expression levels of genes involved in abscisic acid (ABA) biosynthesis were down-regulated in IC seeds, while the transcription levels of the genes related to gibberellin (GA) biosynthesis were up-regulated. Consistently, this was also reflected in decreasing ABA concentration and increasing active GA4 concentration in IC seeds, resulting in an increased GA4/ABA ratio. Altogether, shading in mother plant during seed development promoted subsequent seed germination by mediating the biosynthesis of pro-anthocyanidins, fatty acids and phytohormones.

中文翻译：

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种子发育期间母体植物的遮荫促进大豆随后的种子发芽。

到目前为止，在种子发育过程中遮荫对随后发芽的影响尚不清楚。在这项研究中，采用了两种大豆种子生产系统，即单作（MC）和玉米-大豆间作（IC）。与接受正常光谱的MC大豆种子相比，正在发育的IC种子暴露在较高的邻近玉米植物的阴影下。IC种子的发芽速度比MC种子快，而种皮厚度没有显着差异。IC种皮中的可溶性原花色素浓度显着低于MC种皮中的可溶性原花青素浓度，并且记录了IC种中几种类型脂肪酸的浓度变化，这一发现与发芽证据相符。IC种子中脱落酸（ABA）生物合成相关基因的表达水平下调，而赤霉素（GA）生物合成相关基因的转录水平上调。一致地，这也反映在IC种子中ABA浓度降低和活性GA4浓度升高，导致GA4 / ABA比增加。总之，通过调节原花青素，脂肪酸和植物激素的生物合成，种子植物在种子发育过程中的遮荫促进了随后的种子发芽。导致增加的GA4 / ABA比。总之，通过调节原花青素，脂肪酸和植物激素的生物合成，种子植物在种子发育过程中的遮荫促进了随后的种子发芽。导致增加的GA4 / ABA比。总之，通过调节原花色素，脂肪酸和植物激素的生物合成，种子植物在母体中的遮荫促进了随后的种子发芽。