Departament de Biologia Vegetal, Facultat de Biologia, Universitat de Barcelona, Barcelona, Spain.
Plant Biol (Stuttg). 2010 May 1;12(3):475-83. doi: 10.1111/j.1438-8677.2009.00246.x.
To better understand aging in perennials, age-related changes in the physiology of leaves and flower buds of the Mediterranean shrub, Cistus albidus L. were evaluated. Two groups of different ages (5 and 10 years old), both at advanced developmental stages but of similar size, were compared. Total plant biomass, biomass produced per apical meristem and levels of cytokinins, abscisic acid and jasmonic acid in leaves and flower buds, as well as flower production, were measured. No differences in plant size, vegetative growth rates and levels of phytohormones in leaves were observed between 5- and 10-year-old plants. However, they showed significant differences in flower bud development; the older plants having reduced vigour, with 29.6% of flowers reaching anthesis compared to 52.5% in the younger plants. Furthermore, endogenous concentrations of zeatin and abscisic acid in flower buds at stage I (start of flower organ formation) were 61% and 41%, respectively, smaller in 10- than in 5-year-old plants. At stage II (with all flower organs formed), zeatin and abscisic acid concentrations decreased by ca. 90% and 80%, respectively, but differences between age groups were still evident (60% and 29% for zeatin and abscisic acid, respectively). Jasmonic acid levels in flower buds decreased by 80% from stage I to II, but did not differ between age groups. Despite reductions in flower bud vigour, total number of flowers per individual was not significantly different between age groups, so that an age-related loss in reproductive vigour at the organ level did not lead to a decrease in flower production at the whole plant level.
为了更好地了解多年生植物的衰老过程，评估了地中海灌木 Cistus albidus L. 的叶片和花芽的生理学与年龄相关的变化。比较了两组不同年龄（5 岁和 10 岁）的个体，它们都处于高级发育阶段，但大小相似。测量了叶片和花芽中的总植物生物量、每个顶芽产生的生物量以及细胞分裂素、脱落酸和茉莉酸的水平，以及花的产量。在 5 岁和 10 岁植物之间，叶片的植物大小、营养生长速度和植物激素水平没有差异。然而，它们在花芽发育方面表现出显著差异；较老的植物活力降低，有 29.6%的花达到开花期，而较年轻的植物有 52.5%。此外，在 I 期（花器官形成开始时），花芽中玉米素和脱落酸的内源浓度分别比 10 岁植物低 61%和 41%。在 II 期（所有花器官形成时），玉米素和脱落酸的浓度分别下降了约 90%和 80%，但年龄组之间仍存在差异（玉米素和脱落酸分别为 60%和 29%）。从 I 期到 II 期，花芽中的茉莉酸水平下降了 80%，但在年龄组之间没有差异。尽管花芽活力降低，但个体的总花数在年龄组之间没有显著差异，因此器官水平上生殖活力的年龄相关损失并没有导致整个植物水平上花产量的减少。
