Morphological Variability of Wild Cardoon (Cynara cardunculus L. var. sylvestris) Populations in North of Tunisia

Abstract

In north of Tunisia, wild cardoon (Cynara cardunculus L. var. sylvestris (Lamk) Fiori) is called “khurshef.” It is consumed mainly for its fleshy stems and leafstalks in some traditional dishes. In some regions, heads were used to prepare cheese. North Tunisian germplasm has been currently damaged by severe genetic erosion, pollution, urbanization, and bad farming practices. In order to preserve this species and to assess morphological relationship between accessions, the present study aims to prospect and to characterize individuals in several areas of the north of Tunisia. Six populations were collected and then 20 individuals per population were evaluated using UPOV (International Union for the Protection of New Varieties of Plant) descriptors related to leaves, leafstalks, and heads. Multivariate analyses were used to elucidate relationship among the studied populations. Principal components analysis revealed more diversity within each population. Cluster study reveals large variability among populations. This analysis allows classifying the germplasm of wild cardoon into five groups. Similarities observed between ecotypes despite their distinctiveness of geographic origin suggest a narrow genetic base. These analyses are very useful for the management and the use of wild cardoon in future breeding programs for Cynara germplasm.

Genetic variability in wild cardoon (Cynara cardunculus L. var. sylvestris) revealed by SSR markers and morphological traits

“…In this study, the most part of genetic variation was found within populations and a considerable level of gene exchange was observed between populations. According to the high level of genetic diversity proved in a previous study (Ben Ammar et al, 2014), it would be very interesting to manage these genetic resources by the establishment of an ex situ collection. Moreover, it would be useful to complete this work by estimating the genetic diversity of this understudied germplasm using biochemical and other morphological characterization.…”

“…Recently, the study conducted by Ben Ammar et al (2014) and Khaldi et al (2012) has revealed a large variability among wild cardoon populations. Therefore, the objective of this http://dx.doi.org/10.1016/j.scienta.2015.01.017 0304-4238/© 2015 Elsevier B.V. All rights reserved.…”

Understanding dormancy breakage and germination ecology of Cynara cardunculus (Asteraceae)

“…For the lesser dormant population, a similar treatment duration resulted in total dormancy loss, without induction into secondary dormancy with extended storage. Differences among C. cardunculus populations were already described for many attributes (Ben Ammar et al ., ), for instance tolerances to abiotic stress (Raccuia et al ., ) and chemical profiles (Portis et al ., ). Here, differences between populations were recorded for the first time for response to temperature‐dependent dormancy release.…”

“…The rest of the experiments were performed using achenes collected in Olavarr ıa in 2015 and 2016. For this set of experiments, achenes were cleaned and immediately stored at À18°C to maintain their initial dormancy level (Benech-Arnold et al, 2006) until used in the experiments.…”

“…Seed dormancy alleviation is associated with a widening of the environmental conditions at which seeds can germinate. In many cases, when dormancy level is sufficiently low, seeds lose their requirement of alternating temperatures and/or light to germinate and can germinate under a wide range of constant temperatures (Benech-Arnold et al, 2000). Knowledge about the way in which the environment modulates dormancy alleviation in weed species is useful to predict germination and seedling emergence patterns in the field, and to develop rational strategies of weed management (Ramirez et al, 2014).…”