Protocolos para conservação ex situ de recursos genéticos de Butia (Arecaceae) e Solanum (Solanaceae)

Abstract

Searching for alternatives that conserve the native and wild genetic resources of Brazilian biodiversity is extremely necessary, for the maintenance of plant diversity, and to guarantee the future of the human food base. Thus, the present study aims to adapt ex situ conservation protocols that can meet the long-term conservation of species of the Butia genus and wild potato species. For Butia species, in vitro cultivation, organogenesis and cryopreservation methodologies were carried out. For the genus Butia, success was achieved in the in vitro cultivation of the three analyzed species, using 4.5 µM of 2,4-D (2,4- dichlorophenoxyacetic acid), reaching 90% germination in Butia odorata (Barb. Rodr.) Noblick, 80% for Butia lallemantii (Deble & Marchiori) and Butia exilata Deble & Marchiori. For organogenesis, the treatment with 35.60 µM of silicon promoted the development of part area, being 96% for B. odorata, 88% for B. lallemantii and 75% for B. exilata. In cryopreservation, the best results were obtained with the adaptation of droplet vitrification, with 80% germination of cryopreserved embryos of B. odorata, 65% for B. lallemantii and 75% for B. exilata. The present work allowed the cryopreservation of the three species of the genus Butia, thus making this genetic material available in cryobanks, emphasizing that these results are unprecedented for the species for B. lallemantii and B. exilata. For wild potato species, micropropagation, production of encapsulable units and germination of botanical seeds and cryopreservation were carried out, using the rapid freezing methodology, both for plant material established in vitro and for botanical seeds. In micropropagation there were no significant differences for the concentration of salts in the culture medium and without the need to use growth regulators to induce shoots or rooting, obtaining more than 90% of acclimatization for the seedlings of S. chacoense, S. malmeanum and S. calvencens. For the composition of the encapsulation matrix, the best result was with 50% of salts from the culture medium in which there was 96% germination of S. chacoense capsules. In cryopreservation, 82% of S. chacoense bud regeneration occurred, 72% for S. malmeanum in the encapsulation, saturation and vitrification methodology, while for S. calvencens there was 96% of bud regeneration in encapsulation and vitrification. botanical seeds, treatment T2 (immersion in a solution containing 250 µM of GA3) is indicated, in which 92% germination occurred in S. malmeanum, 40% for S.commersonii and 72% for S. tuberosum. In the cryopreservation of botanical seeds with immersion in PVS2 for 30 minutes, 68% germination was reached in S. malmeanum, 28% S. commersonii and 65% S. tuberosum.