Orchids of the genus Dendrobium hold a high economical value in the international markets both as pot plants or cut flowers, and for the production of some metabolites with antioxidant and anti-tumoral activities. Manipulating ploidy levels of Dendrobium species is one of the possible methods to develop new varieties with increased ornamental value and a higher production of secondary metabolites. In this work, we present a new and fast flow cytometry approach to obtain and select Dendrobium phalaenopsis × Dendrobium loddigesii polyploids, through an early in vitro screening on protocorm like bodies (PLBs) after antimitotic treatment. Our approach allows the identification of the best time of treatment on control PLBs and the assessment of best conditions for polyploid recovery just one month after treatments, by using Cycle Value. We were able to discard about the two-third of the unchanged material by drastically reducing the explants to work with and the corresponding costs. Different conditions, regarding concentrations and exposition time, were tested using colchicine or amiprophos-methyl (APM). A high polyploids recovery, up to 80%, were obtained with both antimitotic agents, and those materials were further characterized by liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS), to identify independent polyploids explants with increased levels in high-value molecules as shihunidine and hircinol, together with stochastic events and genotype-specific metabolite fluctuations.

Cynara cardunculus L. (2n=34) is a traditional vegetable crop of the Mediterranean basin including two cultivated varieties: Cynara cardunculus L. var. scolymus L (globe artichoke), grown for its fleshy capitula, and C. cardunculus var. altilis DC (cardoon) grown for its succulent young leaves. Unlike other species belonging to the family of Asteraceae (i.e., sunflower, lettuce and chicory), the genome organization and the chromosome morphology both of globe artichoke and cardoon has not been sufficiently explored. To our knowledge, no karyotype analysis for this species is available so far. Different factors make very difficult the definition of chromosome morphology such as: the plant rigid cell wall, the presence of cellular debris, the thick cytoplasmic remains and the small size of the 34 chromosomes of Cynara cardunculus. In order to develop an effective chromosome preparation method for globe artichoke karyotyping here we evaluated different chromosome preparation systems and we observed the effect of some spindle inhibitors on globe artichoke cell cycle. The first Cynara cardunculus L var. scolymus L. karyotype is presented.