Seed production and patterns of sex allocation were studied in female and hermaphroditic plants in two gynodioecious populations of Geranium sylvaticum (Geraniaceae). Females produced more flower buds and seeds than hermaphrodites in one of the two study populations. The other female traits measured (pistil biomass, seed number per fruit, individual seed mass) did not differ between the gender ...

Climate warming can modify plant reproductive fitness through direct and indirect pathways. Direct effects include temperature-driven impacts on growth, reproduction, and secondary metabolites. Indirect effects may manifest through altered species interactions, including herbivory, although studies comparing the interactive effects of warming and herbivory are few. We used experimental warming ...

In the present study effects of production history on tuber sprout, root, stem development and crop yield of seed potato cultivars Fambo and Van Gogh were investigated in the High Grade Area of Finland (64.9 N, 25.4 E). The haulms of seed potatoes were destroyed at the time of flowering (50 days after planting, DAP), three weeks after flowering (75 DAP) and as a control the haulm was left to na...

We determined female frequency of 23 populations of the gynodioecious Geranium sylvaticum (Geraniaceae) in Finland. We compared our results to previous results on this species from the 1960s in order to reveal putative changes in female frequencies. Because females may be maintained in gynodioecious populations if their seed production or offspring quality is higher than that of hermaphrodites,...

Unlike other major crops in which seeds provide most of the economic value, cotton seed is largely a by-product of more valuable fiber production and represents only approximately 15% of the farm gate value of the cotton crop. A cotton plant normally produces about 1.6 kg of seed for every kg of lint. Following ginning to remove the lint fiber, fuzzy cotton seed is either used directly as anima...

Pine Siskins exemplify normally boreal seed-eating birds that can be sparse or absent across entire regions of North America in one year and then appear in large numbers the next. These dramatic avian "irruptions" are thought to stem from intermittent but broadly synchronous seed production (masting) in one year and meager seed crops in the next. A prevalent hypothesis is that widespread mastin...

Animal pollination mediates both reproduction and gene flow for the majority of plant species across the globe. However, past functional studies have focused largely on seed production; although useful, this focus on seed set does not provide information regarding species-specific contributions to pollen-mediated gene flow. Here we quantify pollen dispersal for individual pollinator species acr...

Mast seeding, the synchronous production of large crops of seeds, has been frequently documented in oak species. In this study we used several North American oak data-sets to quantify within-stand (!10 km) synchrony in mast dynamics. Results indicated that intraspecific synchrony in seed production always exceeded interspecific synchrony and was essentially constant over distances ranging from ...

National survey data collected for 1997 in USDA’s Agricultural Resource Management Study was used to derive implications and pose hypotheses about the impact on pesticide use, production practices, and producer costs of using genetically modified (GM) seed in soybean and cotton production. Results of the analysis suggest concurrence with scientific and industry claims about the environmental qu...