Quantifying Temperature and Osmotic Stress Impact on Seed Germination Rate and Seedling Growth of Eruca sativa Mill. via Hydrothermal Time Model

Germination models are quite helpful in predicting emergence times, dormancy periods, and their applications in crop management. This study investigated the germination behaviors of Eruca sativa Mill. in response to fluctuations in temperatures (T-s) and water potentials (psi(s)). Germination percentage (GP) increased 95% with rising temperature within the range of 20-30 degrees C, and decreased 25% at 5 degrees C. Moreover, each psi and T resulted in a decrease in GP as psi decreased. Further, we noted that the theta T1 value was substantially high at 30 degrees C and in (0 MPa), whereas the theta T2 value was maximum at 10 degrees C (-0.02 MPa) and it decreased with decreasing psi. The maximum hydrothermal time constant (theta HTT) and hydrotime (theta H) values were obtained at 10 and 30 degrees C, respectively. In addition, a linear increase in the GR((g)) pattern was observed at T-b and a decrease below the T-o. The calculated cardinal T-s was 5 degrees C for the base T, and 30 degrees C for both the optimum and ceiling T. The germination characteristics were higher at 30 degrees C having (0 MPa). Therefore, using cardinal temperatures, germination results, and the hydrothermal time model (HTT) could reveal the independent and interactive impacts of both T and the psi on the response of seed germination subjected to diverse environmental conditions.

Automated summary

This study investigated the germination behaviors of Eruca sativa Mill. in response to fluctuations in temperatures and water potentials. The results showed that both increasing temperature and decreasing water potential led to a decrease in germination percentage. Additionally, the germination characteristics were higher at 30 degrees C with 0 MPa.