Short Communication: Timing of stinkweed and shepherd's-purse recruitment affects biological characteristics of progeny

Abstract

Van Acker, R. C. and Cici, S. Z. H. 2012. Short Communication: Timing of stinkweed and shepherd's-purserecruitment affects biological characteristics of progeny. Can. J. Plant Sci. 92: 933–936. The effect of recruitment timing (fall versus spring recruitment) on seed characteristics and performance of two common Canadian facultative winter annual weeds; stinkweed (Thlaspi arvense L.) and shepherd's-purse (Capsella bursa-pastoris L.) was investigated. Seed germination proportion was unaffected by maternal emergence timing but germination was faster for spring versus winter cohort seeds of stinkweed. Proportionally more seeds from winter (fall-recruited) cohorts were rendered non-viable by aging treatments, while for shepherd's purse, aging treatments broke dormancy instead of reducing viability and this was especially true for winter cohort seeds. For both weed species, spring cohort seeds produced earlier flowering plants with greater and lesser biomass allocation to reproductive tissues and roots, respectively. These results show the potential importance of germination timing and maternal effects on weed populations and demonstrate additional complexity in the nature of facultative winter annual weeds, in particular.

Effects of germination time on seed morph ratio in a seed-dimorphic species and possible ecological significance

“…Plants that have a long growing season invest a high amount of biomass in vegetative structures, which subsequently increases their reproductive output (Van Rooyen et al, 1992;Donohue, 2002;Van Acker and Cici, 2012). When life span was shortened by delayed germination, S. corniculata adjusted its life span by shortening the vegetative period but maintained a reproductive period of sufficient length to produce seeds.…”

“…The time of seed germination in a dimorphic species may differ between the diaspores due to differences in dormancybreaking and germination requirements, which are sensitive to temporal environmental variation in the habitat (Donohue, 2005;Baskin and Baskin, 2014). In species with monomorphic diaspores, it has been shown that a delay in germination has direct influences on seedling establishment (Gross and Smith, 1991;Lloret et al, 2009), phenology (Donohue et al, 2007;Chiang et al, 2009), physiology (Kimball et al, 2010(Kimball et al, , 2011, longevity (Rees, 1994), reproduction and fitness (Cohen, 1967;Donohue, 2002), and phenotypic expression of offspring (Galloway, 2002;Van Acker and Cici, 2012). Thus, the influence of germination timing on the subsequent life history states of plants (Donohue et al, 2005b) is critical for the success of desert annual species (Adondakis and Venable, 2004;Kimball et al, 2010) and acts as a selective force in the evolution of post-germination traits (Donohue, 2002;Donohue et al, 2005a).…”

Do winter and summer cohorts of the invasive weed Parthenium hysterophorus differ in seed germination and seedling growth?

“…Intraspecific variation in seed biomass may be explained by temperature experienced by the mother plant during seed development (Peltonen‐Sainio et al, 2011; Platenkamp & Shaw, 1993). During the summer, when climatic conditions are favourable with high temperatures and abundant rainfall, plants invest a large amount of biomass in vegetative structures (dry biomass accumulation), which increases their reproductive output (Van Acker & Cici, 2012). However, seed filling duration usually shortens, thereby reducing seed size (Nguyen et al, 2017) and seed biomass (Young et al, 2004).…”

The Biology of Canadian Weeds. 159.Capsella bursa-pastoris(L.) Medik.

“…The time of emergence of the maternal plant may affect the seed germination and morphology of the seed and plant. Van Acker and Cici (2012) reported that spring emerging plants produced seed that germinated faster, flowered earlier, and resulted in differential allocation of biomass to roots and reproductive tissue.…”