Growing a population of cultivated cardoon (Cynara cardunculus var. altilis DC) for further selection as a reference energy crop

Abstract

A population of cultivated cardoon (Cynara cardunculus var. altilis DC) was grown in Madrid (Spain) as a reference crop to select outstanding individuals for energy applications. The work was carried out within the frame of the Spanish funded projects PROBIOCOM (INIA) and FP13-ENER. Seeds for this work were produced by one of the partners of PROBIOCOM-the Agro-Energy Group of UPM-and came from a clonal crop (in vitro propagated plants) previously grown in Madrid. IMIDRA, as Head of that Project, established the reference crop according to the protocol for cardoon energy crop and was responsible for the crop. Seeds were sown in seed trays and once the plants had true leaves they were transplanted into the field. Collection of field data involved 449 individuals at the rosette stage and the dataset comprised the measurement of plant height, rosette diameter and leaf length; leaf type was determined as well. Individuals exhibiting larger leaf size were selected and categorized into two categories: undivided-like leaf blade (16 individuals) and pinnately lobed leaf blade (12 individuals). For these individuals, leaf fresh weight, number of leaves and leaf length of previously selected leaves were determined. Furthermore, three measurements were performed with a SPAD chlorophyll meter and the Munsell color chart. Morphological features were taken according CPVO-OCVV and UPOV protocols. Most plants exhibited pinnately leaves which generally resulted in larger sizes than the undivided-like leaf plants. Results suggested that the morphological plant type could be used as a preliminary selection criterion of C. cardunculus for biomass production; however, further studies are needed at harvest time to confirm this trend.