Fruit development in trillium. Dependence On stem carbohydrate reserves
Fruit development in trillium. Dependence On stem carbohydrate reserves
复制标题
延龄草的果实发育。
作者：
Lapointe
叶是大多数物种果实成熟的主要碳源。然而，在看到对比光照条件的植物中，如一些春季植物，春季固定的碳可以用于支持夏季光合速率低的果实发育。我们监测碳水化合物含量的根茎（多年生器官）和地上茎延龄草（延龄草直立）在整个生长季节（5月至11月）。在结果阶段开始时，收获携带发育中的果实的茎，除去它们的叶，并将无叶茎在受控条件下保持在水溶液中直至果实完全成熟。这些实验表明，茎碳水化合物含量足以支持果实发育，在没有叶和根茎。据我们所知，这是第一个报告的情况下，完整的水果发展持续只有一个临时的碳水化合物水库。春季茎中碳水化合物的积累使植物能够更好地利用当时的高辐射。许多其他物种可能会建立短期碳水化合物库，以应对生长条件的季节性变化。
Leaves are the main source of carbon for fruit maturation in most species. However, in plants seeing contrasting light conditions such as some spring plants, carbon fixed during the spring could be used to support fruit development in the summer, when photosynthetic rates are low. We monitored carbohydrate content in the rhizome (a perennating organ) and the aboveground stem of trillium (Trillium erectum) over the entire growing season (May-November). At the beginning of the fruiting stage, stems carrying a developing fruit were harvested, their leaves were removed, and the leafless stems were maintained in aqueous solution under controlled conditions up to full fruit maturation. These experiments showed that stem carbohydrate content was sufficient to support fruit development in the absence of leaves and rhizome. This is the first reported case, to our knowledge, of complete fruit development sustained only by a temporary carbohydrate reservoir. This carbohydrate accumulation in the stem during the spring enables the plant to make better use of the high irradiances occurring at that time. Many other species might establish short-term carbohydrate reservoirs in response to seasonal changes in growing conditions.