ABSTRACT
The Gymnocalycium genus includes numerous highly valued species in the ornamental plant market and their propagation is usually carried out using traditional methods. However, there is a lack of information regarding the efficiency of micropropagation through in vitro tissue culture techniques on these species. So, with the objective of establishing an efficient micropropagation protocol that allows for optimizing the plant obtaining processes, the morphogenic potential of Gymnocalycium cv. Fancy has been studied in this work. For this purpose, plants of two different sizes (medium and large) were used as the starting material, from which three types of explants were obtained (apex, central discs and bases). The effect of three plant growth regulators (6-Benzylaminopurine, BAP; Kinetin, KIN; and Thidiazuron, TDZ) at three different concentrations each were studied, and the number of generated shoots, the frequency of appearance of callogenesis and rhizogenesis by explant and condition were assessed. An efficient protocol based on the use of KIN at 4 µM and central discs as a starting explant was developed. Moreover, the obtained sprouts rooted successfully (especially using BAP at 2 µM), and their subsequent acclimatization was very effective. Furthermore, emergence of a new morphotype is presented, that has not previously been described.
ABSTRACT
BACKGROUND: Traditional varieties of tomato, usually associated with excellent organoleptic quality, are increasingly appreciated in European quality markets. A collection of 126 populations of 16 traditional varieties from the east of Spain (a secondary diversity center for tomato) have been evaluated over 2 years in order to determine their potential value as sources of functional compounds, including ascorbic acid, lycopene, ß-carotene and total phenolic content. RESULTS: Population and population × year interaction significantly affected lycopene and ascorbic acid contents, while year effect was also significant for ß-carotene. Despite finding some global trends in certain varieties concerning their functional value, high levels of variation have been found at the intra-varietal level. Populations with high levels of the compounds analysed have been found, as well as different levels of intra-population and inter-year variation. Maximum mean contents for both years have reached 308 mg kg(-1) ascorbic acid, 130 mg kg(-1) lycopene, 30 mg kg(-1) ß-carotene and 89 mg caffeic acid 100 g(-1) total phenolic contents, though it is difficult to identify accessions with joint high values of the three compounds. CONCLUSION: These results open the possibility to promote traditional materials as sources of functional compounds, thus strengthening their quality niches and consolidating their price premium. Additionally, these materials could also be used in breeding programs for quality.
