Seed predation by native and alien rodents can limit plant recruitment and ultimately affect forest dynamics and composition (Campbell & Atkinson 2002, Côté et al. 2003, Hulme 1998, Sánchez-Cordero & Martínez-Gallardo 1998). Even partial consumption of seeds by predators may affect plant community structure, though its importance is poorly understood (Steele et al. 1993, Vallejo-Marín et al. 2006). Despite consumption of relatively large portions of seeds by herbivores, seeds can retain their ability to germinate if the embryo remains intact (Dalling & Harms 1999, Janzen 1972, Mack 1998). Germination of damaged seeds may be accelerated or prolonged (Karban & Lowenberg 1992, Koptur 1998, Vallejo-Marín et al. 2006). Damage by seed pests also facilitates ageing stress; which manifests as decreased seedling vigour, decreased seed viability, lower germination percentages and slower germination rates (Priestley 1986).

Seed germination and seedling vigor can be affected by environmental cues experienced by the mother plant. However, information about how the maternal environment affects seed quality is scarce in ornamental plants. This study aimed to investigate the effects of two different maternal environments on the seed germination and seedling vigor of Petunia × hybrida under a variety of abiotic stresses. Petunia mother plants were grown in either a greenhouse during the summer months or an indoor controlled-temperature-and-light environment. Collected seeds were subjected to external stressors, including polyethylene glycol (PEG), sodium chloride (NaCl), high temperature, and abscisic acid (ABA), to determine seed germination percentage and seedling vigor. Results indicated that seeds harvested from the mother plants grown in a controlled environment germinated better than seeds harvested from the mother plants grown in the greenhouse when suboptimal germination conditions were applied. Additionally, the seedlings from the controlled maternal environment performed better in both ABA and salinity stress tests than the greenhouse seedlings. Interestingly, the greenhouse seedlings displayed less reactive oxygen species (ROS) damage and lower electrolyte leakage than the controlled environment seedlings under dehydration stress. The difference in germination and seedling vigor of seeds from the two different maternal environments might be due to the epigenetic memory inherited from the mother plants. This study highlighted the strong impact of the maternal environment on seed germination and seedling vigor in Petunia and may assist in high-quality seed production in ornamental plants.

Assessments of seed storage physiology among Arecaceae (palm) species are often inconclusive because seeds exhibit diverse responses to low temperature and moisture conditions. Interrelationships between dry matter accumulation, cell structure and water relations during seed development of the endangered Hawaiian endemic palm, Pritchardia remota, suggest that damage from drying results from mechanical strain. Endosperm and fruits accumulate dry mass through most of the 400 d gestation period, but embryos reached maximum dry mass about 250 d post-anthesis (DPA). Mostly sucrose and some triacylglycerols accumulated in the cytoplasm and vacuoles of embryo cells, and organelles in mature embryo cells de-differentiated. Water content and water potential decreased as embryos matured and embryos contained about 0.45 g H₂O (g dry mass)^− 1 ( − 26 MPa) at shedding. Mature embryos survived drying to 0.16 g g^− 1 ( − 49 MPa), but further drying was lethal. A model of allowable cell shrinkage is consistent with the substantial, but incomplete, desiccation tolerance acquired in P. remota embryos, and provides a new framework to explain variation in critical water contents as embryos develop. We suggest that desiccation tolerance, which distinguishes recalcitrant and orthodox physiologies among seeds, can be quantified by mechanical strain when embryo cells shrink during drying.

Native plant sales have increased steadily during the past decade because of consumer concern with invasive plant sales, water conservation, and land management issues. However, native plants are still under-used mostly because of a small market and the lack of education on the use and care of native plants. For example, native plant sales in Florida accounted for only 11% of the total horticultural market in 2005. Within the Florida native plant industry, a small, but competitive market focuses on native wildflowers, but a paucity of information related to opportunities within this segment exists. We sent surveys to 137 members of the Florida native plant industry to learn about their interests, concerns, and trends in the native wildflower market. Survey respondents identified low demand, seed supply, and availability of desired species, plus insufficient customer and industry education as major factors limiting Florida native wildflower (FNW) sales. An overwhelming majority predicted that sales for locally produced FNWs would increase over the next 5 years. Respondents also stated that seed germination, seed storage, and seed production research are vital for the advancement of the industry. This survey provides an excellent opportunity to analyze the current native wildflower market and identify areas to help increase awareness of FNWs.

Wiregrass (Aristida stricta) is an important species for restoration of imperiled pine-grassland ecosystems. However, in situ and ex situ seedling establishment is problematic due to highly variable germination. I assessed seed lot quality with respect to the production of viable and non-viable seeds from seven remnant wiregrass populations occurring in xeric or mesic habitats throughout Alabama, Florida, Georgia, and South Carolina. Additionally, I investigated the incidence of contamination and germination following surface sterilization. Approximately 55 to 90% of seeds were non-viable due to lack of seed fill and fungal contamination. The number of empty seeds always outweighed that of infected seeds. Populations were similar for seed lot quality when grouped by habitat. Alternatively, populations were heterogeneous for seed lot quality when grouped by geographic region. Seeds from all populations were infected with Curvularia and most were infected with Sorosporium. Surface sterilization with up to a 10% bleach solution did not eliminate pathogens on otherwise viable, healthy seeds suggesting that internal seed tissues may have harbored infection. The high level of non-viable seeds implies that large quantities of seeds are required in order to meet restoration objectives and that caution should be exercised if inter-population seed movement is needed.