Effect of Low and High Temperature Regimes on Seed Dormancy and Germination of Ricimus Communis (Castor Oil plant) using Thermal Time Method
Year: 2025
Type: article
Abstract: The Ricinus communis, commonly known as the castor oil plant, is widely cultivated for its oil-rich seeds.Understanding the effects of temperature on seed dormancy and germination is crucial for optimizing agricultural practices.Seed dormancy and germination are significantly influenced by environmental factors, particularly temperature, which regulates metabolic processes essential for seed development.This study aimed at investigating the impact of extreme low and high temperature regimes on the seed dormancy and germination of Ricinus communis using the thermal time method.The experiment was conducted under controlled temperature conditions.Seeds of Ricinus communis were subjected to two temperature regimes: low (wet) and high (heat).Seed emergence was monitored at regulated times (5, 10, and 15 days).Data on seed emergence rates (%SDE), plant height, number of leaves, and plant width were collected.The thermal time model was employed to analyze germination parameters, including actual temperature (T), maximum temperature (Tc), base temperature (Tb), optimal temperature (To), initial germination time (tg), and thermal time (Tt).The study found that temperature regimes significantly influenced seed emergence and early plant development.Under wet conditions, seed emergence rates were 18.18%, 13.64%, 9.09%, and 12.12% at 5, 10, and 15 days, respectively.In contrast, high temperature regimes resulted in lower seed emergence rates, with the highest at 15.15%.Plant height, number of leaves, and plant width varied significantly between treatments.Wet conditions promoted greater plant height and leaf number compared to high temperature conditions.The results indicate that extreme temperatures adversely affect seed emergence and early growth of Ricinus communis.The thermal time method effectively elucidates the temperature ranges that may influence seed dormancy and germination.For optimal agricultural practices, maintaining temperatures within a moderate range is recommended to enhance seed emergence and plant development.Further research should explore long-term effects of temperature variations and their impact on overall plant yield.
Author: Hemen Terseer Joseph
Institution: Nigeria Police Academy
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: diamond
OpenAlex ID: W4411929574