Genetic relationships among Aster species by multivariate analysis and AFLP markers

Abstract

Fourteen species of Aster were characterized for morphological traits of commercial interest, chromosome number and genetic diversity by AFLP markers to exploit this material not only for breeding purposes but also as source of pharmaceuticals. The variation observed among the Aster species for five morphological traits was summarized by means of discriminant analysis. Three significant canonical variables, accounting for about 96% of total variance, were mainly correlated with capitulum diameter, number of ligulae and leaf length. The morphological variation appeared related to ploidy level of the species. A diploid chromosome number ranging from 10 to 18 was evident in seven species whereas the other species are polyploids with variable chromosome numbers up to 52. The pollen production and stainability were quite variable among Aster species. Furthermore, seven species produced big pollen grains besides normally-sized ones, at a frequency ranging from 1 to 12%, possibly due to 2n pollen production. The possibility that evolution of Aster genus could be driven by 2n gametes and sexual polyploidization is discussed. Implications of 2n gametes for Aster breeding are also mentioned. AFLP analysis of the fourteen Aster species based on six primer combinations revealed a total number of 421 polymorphic amplified DNA fragments. The genetic similarities estimated between the Aster species, based on both shared and unique amplification products ranged from 0.335 to 0.604 across all species and revealed a geographically based clustering within the genus. The highest similarity was detected between A. alpinus and A. amellus with Eurasian origin.

Syncyte formation in the microsporangium of Chrysanthemum (Asteraceae): a pathway to infraspecific polyploidy

“…There is no previous record of syncytes in the Asteraceae. However, several reports have been published on the occurrence of 2n pollen grains in the Asteraceae, for instance in Aster (Cammareri et al 2004) and Chrysanthemum morifolium (Bino et al 1990), although it was unclear how they originate. Generally, meiotic diploidization leading to the formation of 2n or unreduced pollen is widely known in various plant species (Veilleux 1985), and those produced from syncyte formation may be included.…”

Qualitative characterization of cultivated and wild edible plants: mineral elements, phenols content and antioxidant capacity

“…Linear discriminant analysis (Moore et al, 2010;McLaclan, 1992;Webb, 2002;Cammareri et al, 2004) was used to best explain the differences between the different cluster groups obtained by cluster analysis and to evaluate which of the main parameters play the most important roles in determining these differences. The independent variables defined 13 qualitative parameters, and the dependent variable was the wild species.…”

Cytomictic Anomalous Male Meiosis and 2nPollen Grain Formation inMertensia echioidesBenth. (Boraginaceae) from Kashmir Himalaya

“…All polyploids are thought to have arisen from unreduced gametes [ 53 ]. Syncyte/4x cells have been reported in angiospermic families like Asteraceae [ 54 , 55 ], Fabaceae [ 26 ], Poaceae [ 18 ], and Solanaceae [ 56 ]. Elsewhere Boraginaceae falls in the list of top five families in dicotyledons with the highest frequency of intrageneric polyploidy [ 57 ].…”