Species-specific differences in architecture and chemical composition of dodder seeds

Abstract

Dodders (Cuscuta spp.) parasite a broad spectrum of crops and cause harvest devastation. Some efficient approaches aimed at restricting dodder distribution can be based on the control of seed germination. The corresponding processes are being studied, however, to a less extent compared to the development of vegetative or generative Cuscuta organs. This work focuses on the seed architecture and chemical composition of dodder species widely distributed in Europe – the European C. europaea L. and the Eastern dodder C. monogyna Vahl. We show that both species have special endosperm architecture and different seed coat thickness. Furthermore, histochemical staining revealed peculiar storage compounds composition and localisation in seeds. Starch deposits occurred directly beneath C. europaea testa, while only in the embryo in C. monogyna. Oleic, palmitic and linoleic acids detected by GC–MS were the most abundant fatty acids (FAs) in seeds of both dodders. Allocation of oil bodies and species-specific testa structure in the hilar region coincide with the dodders’ germination rates. The observed features likely affect seed germination, dormancy and host dependence of the individual species. Deeper knowledge on the corresponding processes and on the seed structure might provide a basis for efficient and environment-friendly control of dodders.