Genetic structure of the genus Lemna L. (Lemnaceae) as revealed by amplified fragment length polymorphism

Abstract

Duckweeds (Lemnaceae) are extremely reduced in morphology, which made their taxonomy a challenge for a long time. The amplified fragment length polymorphism (AFLP) marker technique was applied to solve this problem. 84 clones of the genus Lemna were investigated representing all 13 accepted Lemna species. By neighbour-joining (NJ) analysis, 10 out of these 13 species were clearly recognized: L. minor, L. obscura, L. turionifera, L. japonica, L. disperma, L. aequinoctialis, L. perpusilla, L. trisulca, L. tenera, and L. minuta. However, L. valdiviana and L. yungensis could be distinguished neither by NJ cluster analysis nor by structure analysis. Moreover, the 16 analysed clones of L. gibba were assembled into four genetically differentiated groups. Only one of these groups, which includes the standard clones 7107 (G1) and 7741 (G3), represents obviously the "true" L. gibba. At least four of the clones investigated, so far considered as L. gibba (clones 8655a, 9481, 9436b, and Tra05-L), represent evidently close relatives to L. turionifera but do not form turions under any of the conditions tested. Another group of clones (6745, 6751, and 7922) corresponds to putative hybrids and may be identical with L. parodiana, a species not accepted until now because of the difficulties of delineation on morphology alone. In conclusion, AFLP analysis offers a solid base for the identification of Lemna clones, which is particularly important in view of Lemnaceae application in biomonitoring.

Taxonomy of duckweeds (Lemnaceae), potential new crop plants

“…However, according to our investigations, the morphological differences between L. yungensis and L. valdiviana Phil. are not very distinct and the molecular analysis also does not provide markers for a clear differentiation between the two species (Bog et al, 2010;Borisjuk et al, 2015). In-depth molecular analysis might provide a substantial basis for further conclusions in this respect.…”

“…Within the last three decades, quite a number of changes have been introduced to taxonomic classification of duckweeds in comparison to the published key. Moreover, molecular taxonomy and barcoding of duckweed species (Wang et al, 2010;Bog et al, 2010Bog et al, , 2013Bog et al, , 2015Borisjuk et al, 2015) has made huge progress and it aids in identification of duckweed species. However, it is not practically and economically viable to determine each of the collected duckweed clones by Amplified Fragment Length Polymorphism (AFLP) or by sequencing of DNA markers.…”

Zinc conferred cadmium tolerance in Lemna minor L. via modulating polyamines and proline metabolism

“…Lemna minor L., a member of the duckweed family, lives in many types of fresh water ecosystems (Bog et al 2010). In particular, it has been commonly used as a test organism in ecotoxicological and environmental studies (Horvat et al 2007;Khellaf and Zerdaoui 2010), owing to the physiological properties (small size, high multiplication rates and vegetative propagation).…”

Genetic transformation of Indian isolate of Lemna minor mediated by Agrobacterium tumefaciens and recovery of transgenic plants

“…The gene transfer in duckweed in general and in L. minor in particular has, so far, been difficult and challenging because of their inherent recalcitrance to in vitro culture and regeneration from cells and calli. Genetic transformation via Agrobacterium in L. gibba G3 and L. minor 8627 and 8744 (Yamamoto et al 2001) and via particle bombardment in Wolffia columbiana (Kruse et al 2002) have been attempted, although stable transformation still awaits optimization (Bog et al 2010).…”