Seeds of several palms are reserve-rich, and have a complex and poorly understood mobilization. The massive endosperm and embryo of Acrocomia aculeata Lodd. ex Mart. possess large amounts of proteins, polysaccharides, and lipids. We evaluated cell features related to reserve mobilization during germination and initial development of seedlings of A. aculeata. Samples of the haustorium (the cotyledonary blade) at different developmental stages and of the entire digestion zone of the endosperm were processed by standard methods for ultrastructural evaluation. The haustorium reserve mobilization begins when germination starts, and proteins are the first to be metabolized, followed by polysaccharides and lipids. Haustorial cells present lipid bodies associated with glyoxysomes and protein vacuoles, which are involved in lipid mobilization. The digestion zone of the endosperm comprises cell layers adjacent to the haustorium, in which reserve mobilization begins after the protrusion of the cotyledonary petiole. The endosperm reserve mobilization is similar to observed in the haustorium, firstly proteins, polysaccharides, and lipids in the end. The abundant carbohydrates in the cell walls of endosperm are hydrolyzed, and the cells lose integrity, while digestion products accumulate around the haustorium. The sinuosities observed in the plasma membrane and the organelles predominating in the epidermal cells of the haustorium are consistent with absorption and transitory storage of reserves, and there is no evidence of the secretion of enzymes that can act in the mobilization of endosperm reserves. Therefore, the endosperm has a storage and self-degradation function, and the products of hydrolysis are transported towards the haustorium via the apoplastic route.

中文翻译：

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Acrocomia aculeata (Arecaceae) 种子储备动员过程中代谢途径和易位途径的超微结构方面

几种棕榈树的种子储量丰富，并且具有复杂且知之甚少的动员。Acrocomia aculeata Lodd 的大量胚乳和胚胎。前马特。含有大量的蛋白质、多糖和脂质。我们评估了与 A. aculeata 幼苗萌发和初始发育期间储备动员相关的细胞特征。通过标准方法处理处于不同发育阶段的吸器（子叶叶片）和整个胚乳消化区的样品以进行超微结构评估。吸器储备动员在萌发开始时开始，蛋白质首先被代谢，然后是多糖和脂质。Haustorial 细胞呈现与乙醛酸体和蛋白质液泡相关的脂质体，它们参与脂质动员。胚乳的消化区包括与吸器相邻的细胞层，其中在子叶叶柄突出后开始储备动员。胚乳储备动员类似于在吸器中观察到的，首先是蛋白质、多糖和脂质。胚乳细胞壁中丰富的碳水化合物被水解，细胞失去完整性，而消化产物在吸器周围积聚。在质膜和吸器表皮细胞中占主导地位的细胞器中观察到的弯曲与储备的吸收和暂时储存一致，并且没有证据表明可以在胚乳储备动员中起作用的酶的分泌。因此，胚乳具有储存和自降解功能，