Long-term preservation of Cicer arietinum L. germplasm by in vitro propagation and cryopreservation

Chickpea (Cicer arietinum L.) is one of the most important pulse worldwide. This crop plays a significant role to maintain soil fertility through symbiotic N fixation, as well as in the Mediterranean diet for its important content of noble protein. In South Italy, particularly in the Puglia region, many traditional landraces are still cultivated in marginal areas, becoming therefore at strong risk of genetic erosion or even extinction. In vitro culture is a useful and innovative approach for the collection and the long-term preservation of threatened germplasm by means of the cryopreservation technology, as ex situ conservation strategy complementary to traditional ones. The aim of this study was to develop an efficient protocol for the multiplication and cryopreservation of two accessions of an Apulian black chickpea threatened landrace. Seeds of Apulian black chickpea were inoculated on agarized sucrose-free nutrient medium. The cotyledonary node and axillary buds were excised from the seedlings and then cultured on the same medium, supplemented with 6-benzylaminopurine and sucrose. After three subculture cycles, shoot tips from in vitro proliferated shoots were induced to rooting on IBA or used for germplasm conservation by comparing three cryopreservation techniques, i.e. PVS2-vitrification, droplet-vitrification and V-cryoplate. The results are very promising in terms of explant survival. However, the study should now progress to optimize a recovery medium, able to further improve shoot regrowth rates and plantlet formation in post-cryopreservation.