Growth dynamics of the branching system in grasses: an architecture-based methodology for quantitative evaluation applied to two genotypes of Paspalum vaginatum

Abstract The aerial growth dynamics of the shoots of the widespread turfgrass Paspalum vaginatum was studied. With the aim of identifying quantitative differential features between two genotypes, plants were cultivated outdoors in pots during two consecutive summers. Axes of different branching order were marked for periodical observation to quantify internode production rate, axis production rate, covering rate and reproductive effort. The genotypes differed significantly in the following quantitative features: plagiotropic vs. orthotropic axes proportion, internode production rate, flowering vs. vegetative tiller ratio, vegetative cover and spatial distribution of the canopy. Knowledge of these features may help to understand the great plasticity and adaptability of this species to multiple environmental conditions.

摘要 本研究针对广泛分布的草坪草海雀稗（Paspalum vaginatum）的地上枝条生长动态开展研究。为明确两种基因型间的定量差异特征，本研究于连续两个夏季将供试植株以盆栽方式露地栽培。对不同分枝级数的枝条进行标记并定期观测，以量化节间生成速率、枝条生成速率、覆盖速率及繁殖投入。两种基因型在以下定量特征上存在显著差异：斜生枝条与直立枝条的占比、节间生成速率、开花分蘖与营养分蘖的比例、营养覆盖度以及冠层空间分布。明晰上述特征，有助于理解该物种对多样环境条件的极强可塑性与适应性。