Effects of Clinostat rotation on stem morphology of Pisum Sativum

초록

Understanding how plants regulate growth and structural form under controlled modulation of gravity-vector persistence is essential for both space agriculture and terrestrial crop biomechanics. While clinostats are widely used as ground-based tools to study gravity-regulated responses, they alter the temporal structure of the gravitational stimulus rather than reproducing true microgravity, with most studies focused primarily on qualitative suppression of gravitropic curvature. Therefore, this study established a quantitative, morphology-based framework to evaluate shoot responses to controlled gravity-vector perturbation using a 2-D clinostat. Pea seedlings (Pisum sativum L.) were subjected to five graded gravity-vector perturbation treatments, spanning static horizontal exposure and continuous clinostat rotation at multiple speeds. Stem morphology was monitored over 10 days using time-resolved image analysis and final destructive measurements. Temporal analyses showed that stem straightness reflects an integrated postural response governed by the balance between gravity-induced bending and intrinsic straightening mechanisms. Continuous rotation suppressed cumulative curvature compared with the static horizontal condition, whereas the non-rotating vertical control maintained near-constant straightness. Increased inter-individual variability at 1 rpm indicated a transitional perturbation regime, whereas higher rotation speeds produced more consistent postural stabilization. Straightness and slenderness were not correlated at the final stage, demonstrating that posture regulation and growth allocation represent functionally independent axes of shoot adaptation under gravity perturbation. © 2026 Committee on Space Research (COSPAR).

키워드