Extending Populus seed longevity by controlling seed moisture content and temperature

Area of Science:

• Botany
• Plant Conservation
• Seed Biology

Background:

• Populus davidiana and P. koreana are vital plantation and biofuel resources.
• Ex-situ seed conservation strategies for these poplar species are not well-established.

Purpose of the Study:

• Determine optimal long-term seed storage conditions for P. davidiana and P. koreana.
• Evaluate seed viability based on seed water content, storage temperature, and duration.

Main Methods:

• Assessed viability of poplar seeds at varying seed water contents (SWCs).
• Tested storage temperatures including room temperature, 4°C, -18°C, -80°C, and liquid nitrogen.
• Monitored germination rates over extended storage periods.

Main Results:

• P. davidiana seeds (<6% SWC) viable for 4 weeks at room temperature.
• P. koreana seeds showed poor room temperature storability.
• P. davidiana seeds (3% SWC) maintained 74% viability after 36 months at 4°C.
• P. davidiana seeds (9-18% SWC) showed >89% viability after 48 months at -18°C.
• Optimal storage for P. davidiana was -80°C (91-98% viability after 48 months, 3-24% SWC).
• P. koreana seeds (<20% viability after 36 months at -18°C and -80°C, 3-24% SWC).
• Liquid nitrogen immersion showed no significant difference for either species.

Conclusions:

• Long-term ex-situ seed conservation is feasible for P. davidiana under specific low-temperature conditions.
• P. koreana presents significant challenges for long-term seed conservation.
• Findings provide critical data for conserving valuable poplar genetic resources.