[Paper Review] Cryopreservation of pineapple (Ananas comosus) apices

María Teresa González-Arnao, M. Marquez Ravelo+3 more|arXiv (Cornell University)|Aug 29, 2020

Plant tissue culture and regeneration30 citations

TL;DR

The paper compares encapsulation-dehydration and vitrification for freezing pineapple apices, with vitrification showing positive results under specific preculture, loading, and dehydration conditions, yielding survival across three varieties.

ABSTRACT

The encapsulation-dehydration and vitrification techniques were experimented for freezing apices of pineapple in vitro plantlets. Positive results were achieved using vitrification only. Optimal conditions included a 2-d preculture of apices on medium supplemented with 0.3M sucrose, loading treatment for 25 min in medium with 0.75M sucrose + 1M glycerol and dehydration with PVS2 vitrification solution at 0 degrees C for 7 h before rapid freezing in liquid nitrogen. This method resulted in 65, 35 and 25% survival with apices of varieties Puerto Rico, Perolera and Smooth Cayenne, respectively. Recovery of cryopreserved apices took place directly, without transitory callus formation.

Motivation & Objective

• Motivate improving long-term germplasm preservation for pineapple by evaluating cryopreservation methods.
• Assess encapsulation-dehydration versus vitrification for pineapple apices in vitro plantlets.
• Identify optimal preculture, loading, and dehydration conditions that maximize post-thaw survival.

Proposed method

• Test encapsulation-dehydration and vitrification techniques on in vitro pineapple apices.
• Use a 2-day preculture with 0.3 M sucrose.
• Apply loading treatment for 25 minutes in medium with 0.75 M sucrose + 1 M glycerol.
• Dehydrate with PVS2 at 0 C for 7 hours before rapid freezing in liquid nitrogen.
• Assess survival and recovery after thawing, noting direct recovery without transitory callus formation.

Experimental results

Research questions

• RQ1 Does vitrification outperform encapsulation-dehydration for pineapple apices cryopreservation?
• RQ2 What are the optimal preculture, loading, and dehydration conditions to maximize post-thaw survival?
• RQ3 How do different pineapple varieties respond to the cryopreservation protocol?

Key findings

• Vitrification produced positive results; encapsulation-dehydration did not yield similarly favorable outcomes.
• Under the reported optimal conditions, survival percentages were 65% (Puerto Rico), 35% (Perolera), and 25% (Smooth Cayenne).
• Post-thaw recovery occurred directly without transitory callus formation.
• The protocol involved a 2-d preculture with 0.3 M sucrose, loading in 0.75 M sucrose + 1 M glycerol for 25 min, and PVS2 dehydration at 0 C for 7 h prior to liquid nitrogen cooling.