根尖分生组织细胞核大小:一个可能用于植物入侵性评估的新指标(英文)

植物的入侵性与DNA C-值之间存在统计学上的负相关关系。在这种关系中,细胞和细胞核大小可能起关键作用,因此我们推测分生组织细胞核大小在评估植物或至少某些分类群的入侵性方面有潜在的应用价值。本研究以豌豆属(Vicia)5种入侵能力不同的植物为材料,观察了它们的分生组织染色体、细胞核和细胞大小以及有丝分裂速率,同时测定了种子产量、单位种子干重产生的幼苗生物量(近似于幼苗相对生长速率)和生活史的长短。结果显示根尖分生区细胞核较小的植物细胞较小,细胞分裂速率快,单位种子干重产生的幼苗生物量高,种子小而数量多,生活史短。这些结果表明5种豌豆属植物中分生组织细胞核较小的倾向于具有较高的入侵性,其原因主要是:(1)能够产生小而多的种子;(2)具有较高的有丝分裂速率、相对较快的幼苗生长速率和短的生活史。分生组织细胞核大小影响植物入侵性与DNA C-值的作用是一致的,在植物入侵性评估模型中,分生组织细胞核大小在评估植物入侵性方面可能具有潜在的应用价值,而且其测定方便、费用低廉。但是,这一指标的应用范围和条件需要进一步筛选。

Root Meristematic Karyon Size: Possible New Index in the Evaluation of Plant Invasiveness

Many reports have found a statistically negative correlation between DNA C-value and plant invasiveness, with meristematic karyon size playing a key role in this correlation according to previous research. We hypothesized that meristematic karyon size could be applied as an evaluation index of plant invasiveness for at least some taxa. To test this hypothesis, we examined the sizes of karyons, cells, and mitosis rates of five Vicia species with different invasiveness and DNA C-values, and also investigated their seed production, seedling weight/dry seed weight (similar to relative seedling growth rate), and their life spans. Results showed that plants with smaller meristematic karyons were prone to have smaller chromosomes, karyons, cells, and seeds, quicker mitosis, higher relative seedling growth rate, shorter generation time, and produce more and smaller seeds. Furthermore, among the five Vicia species, plants with smaller meristematic karyons exhibited higher invasiveness, which may be explained by two aspects: (1) smaller seeds with much higher seed production; and (2) higher rates of cell division and seedling growth with shorter generation times. The effects of meristematic karyon size on plant invasiveness coincided with that of the DNA C-value. Therefore, for plant invasiveness evaluation models, meristematic karyon size has potential value in invasiveness assessment due to its convenience and lower expense, though more work is needed to determine its application scope and methodology.