Validation of in vitro conservation of pineapple germplasm [Ananas comosus (L.) Merr.] for ten years based on field morphological characterization

The genetic erosion of the Ananas Mill. genus has been accelerating in recent years. In the Pineapple Active Germplasm Bank (AGB) of the Embrapa Cassava and Fruits research unit ( Embrapa Mandioca e Fruticultura ), in vitro safety duplication has been an efficient strategy to protect this important germplasm. However, there are indications that in vitro culture conditions can cause somaclonal variations that interfere in the rescue and subsequent cultivation of the genetic material. Therefore, the objective of this work was to evaluate in field conditions the genetic stability of 45 accessions of different botanical varieties of Ananas , after in vitro conservation for 10 years, and to consolidate the efficiency of this type of conservation. Six plants of each accession were acclimatized and submitted to all the steps until transplantation to the field, where the morphological characterization was performed based on 21 quantitative and qualitative descriptors in two production cycles of pineapple plants. The accessions presented a normal production cycle, with genetic variations only noted in accessions AGB-003 and AGB-020 ( Ananas comosus var. bracteatus (Lindl.) Coppens & F. Leal]). Some accessions in this evaluation could not be grouped with their corresponding plants grown in the AGB field, mainly regarding quantitative data. This was due to the greater vigor of these plants because they came from in vitro culture and were virus free. The results demonstrated the morphological stability of the preserved accessions even after the long in vitro conservation period, permitting the validation of this technique as a secure and efficient strategy to preserve pineapple germplasm.