Diversity of Seed Coat Ultrastructure and Soluble Carbohydrate Content
 in Lupinus 

Dariusz J. Michalczyk1*, Agnieszka I. Piotrowicz-Cieślak1, Ewa Sawicka-Sienkiewicz2, Renata Galek2, Anna Bochenek1, and Katarzyna Głowacka1

1Department of Plant Physiology and Biotechnology, University of Warmia and Mazury, ul. Oczapowskiego 1A, 10-718 Olsztyn, Poland
2Department of Plant Breeding and Seed Production, 
University of Agriculture, ul. Cybulskiego 34, 50-205 Wrocław, Poland

*e-mail: darim@uwm.edu.pl

Received August 10, 2005; revision accepted January 19, 2006

Seed sculpture, seed coat thickness and soluble carbohydrate profiles were compared in three lupin species, each represented by three different genetic lines, from sections Pilosus (L. pilosus) and Atlanticus (L. atlanticus, L. cosentinii). Seed coat thickness varied most in the three lines of L. pilosus (330–1000 µm), while in the other species it varied little from 400 µm thickness. The studied seeds accumulated approximately 100 mg/g d.m. soluble carbohydrates. The obtained results together with published data suggest that the soluble carbohydrate composition of seeds is clearly section-specific in Lupinus sections Pilosus and Atlanticus. Sect. Pilosus was characterized by a high level of galactosyl cyclitols, while seeds of sect. Atlanticus contained much higher amounts of the raffinose family oligosaccharides. In all species, however, the dominating soluble carbohydrate was stachyose. The results on the biochemical parameters analyzed in this paper confirm that L. atlanticus and L. cosentinii are more closely related to each other than to L. pilosus. The seed coat roughness/smoothness criterion seems inadequate for building a classification of lupin species, as one of the analyzed lines of L. pilosus, formally ascribed to the rough-seeded lupins, produces smooth seeds.

Key words: Lupin seeds, seed sculpture, seed coat thickness, soluble carbohydrates, galactosyl cyclitols.