Histological characterization of Passiflora pohlii Mast. root tips cryopreserved using the V-Cryo-plate technique

Area of Science:

• Plant Biotechnology
• Cryobiology
• Plant Anatomy

Background:

• Cryopreservation is vital for plant germplasm conservation, but can cause cellular damage and reduce recovery.
• Passiflora pohlii, a Brazilian native, has agronomic potential and antioxidant saponins in its roots.
• Histological analysis is crucial for understanding cryopreservation effects on plant tissues.

Purpose of the Study:

• To develop an optimized cryopreservation protocol for Passiflora pohlii root tips using the V-Cryo-plate technique.
• To characterize anatomical alterations during cryopreservation using PVS2 and PVS3 solutions.
• To evaluate recovery rates and adventitious root formation after cryopreservation.

Main Methods:

• Root tips from in vitro-derived Passiflora pohlii plants were used.
• The V-Cryo-plate technique was employed for cryopreservation.
• Plant vitrification solutions (PVS2 and PVS3) were applied for varying durations.

Main Results:

• Treatment with PVS2 for 45 minutes resulted in significantly higher recovery (79%) compared to PVS3 (43%).
• The 45-minute PVS2 treatment also yielded the greatest number of adventitious roots.
• Cortical cells showed plasmolysis with PVS2, but pericycle and central cylinder cells remained undamaged; no plasmolysis was observed after 30 days.

Conclusions:

• The V-cryo-plate technique combined with a 45-minute PVS2 treatment is effective for cryopreserving Passiflora pohlii root tips.
• This method ensures high recovery rates and promotes adventitious root development.
• Histological assessment confirmed the safety and efficacy of the optimized cryopreservation protocol.