Trait differentiation between native and introduced populations of the invasive plant Sonchus oleraceus L. (Asteraceae)

There is growing evidence that rapid adaptation to novel environments drives successful establishment and spread of invasive plant species. However, the mechanisms driving trait adaptation, such as selection pressure from novel climate niche envelopes, remain poorly tested at global scales. In this study, we investigated differences in 20 traits (relating to growth, resource acquisition, reproduction, phenology and defence) amongst 14 populations of the herbaceous plant Sonchus oleraceus L. (Asteraceae) across its native (Europe and North Africa) and introduced (Australia and New Zealand) ranges. We compared traits amongst populations grown under standard glasshouse conditions. Introduced S. oleraceus plants seemed to outperform native plants, i.e. possessing higher leaf and stem dry matter content, greater number of leaves and were taller at first flowering stage. Although introduced plants produced fewer seeds, they had a higher germination rate than native plants. We found strong evidence for adaptation along temperature and precipitation gradients for several traits (e.g. shoot height, biomass, leaf and stem dry matter contents increased with minimum temperatures, while germination rate decreased with annual precipitations and temperatures), which suggests that similar selective forces shape populations in both the native and invaded ranges. We detected significant shifts in the relationships (i.e. trade-offs) (i) between plant height and flowering time and (ii) between leaf-stem biomass and grain yield between native and introduced plants, indicating that invasion was associated with changes to life-history dynamics that may confer competitive advantages over native vegetation. Specifically, we found that, at first flowering, introduced plants tended to be taller than native ones and that investment in leaf and stem biomass was greater in introduced than in native plants for equivalent levels of grain yield. Our study has demonstrated that climatic conditions may drive rapid adaption to novel environments in invasive plant species.

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Invasive Plant Species: Results of a Consumer Awareness, Knowledge, and Expectations Survey Conducted in Pennsylvania

Journal of Environmental Horticulture ◽

10.24266/0738-2898-24.1.53 ◽

2006 ◽

Vol 24 (1) ◽

pp. 53-58

Author(s):

Kathleen M. Kelley ◽

Janine R. Conklin ◽

James C. Sellmer ◽

Ricky M. Bates

Keyword(s):

Plant Species ◽

Invasive Plants ◽

Invasive Plant ◽

Native Plants ◽

Invasive Plant Species ◽

Consumer Awareness ◽

Attitudes And Behaviors ◽

Potential Problems ◽

Survey Results ◽

Alternative Species

Abstract Consumers were surveyed at the 2004 Philadelphia Flower Show in Philadelphia, PA, from March 8–10, to quantify their attitudes and behaviors towards invasive plant species and potential problems associated with purchasing and planting them. A majority of the 341 participants (81.5%) was aware that non-native plants were used in the landscape and that these plants may be invasive in natural areas. Less than half (40.1%) acknowledged owning plants considered invasive while one third (33.5%) did not know if these plants were growing in their landscapes. Less than half (41.3%) believed that laws should be passed to prevent the sale of non-native plants while 27.8% believed that laws should be passed to allow sale of only native plants in their area. Three distinct consumer segments were identified using Cluster Analysis: ‘Invasive savvy,’ participants knowledgeable about invasives and interested in alternative species; ‘Invasive neutral,’ participants neutral in their decision to purchase alternatives to invasive plants and price sensitive about paying more for plants tested for invasiveness; and ‘Invasive inactive,’ participants were not price sensitive to paying more for plants tested for invasiveness, however, they appeared to oppose the purchase of plants previously listed as invasive which would be available as seedless through breeding and natural selection or other forms of genetic modification. Survey results indicated that media sources (e.g., television and print media) would be effective for educating consumers about potential problems associated with invasive species in the landscape.

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The Relationship of Apis mellifera with Exotic and Native Plants in Boulder County, Colorado

American Journal of Undergraduate Research ◽

10.33697/ajur.2003.017 ◽

2003 ◽

Vol 2 (2) ◽

Author(s):

Kira Krend ◽

Christina Murphy

Keyword(s):

Apis Mellifera ◽

Plant Species ◽

Invasive Plant ◽

Native Plants ◽

Invasive Plant Species ◽

Native Plant ◽

Negative Effects ◽

Native Plant Species ◽

Exotic Invasive ◽

Worldwide Phenomenon

Since honeybees (Apis mellifera) were introduced to North America in the 1600’s, their influence has been profound and widespread. As pollinators, honeybees are extremely valuable economically and are vital to crop pollination. However, their presence has affected native ecosystems, including the plains ecosystem in Colorado. Using recruitment and other unique foraging characteristics, honeybees may be out-competing native pollinators for nectar and pollen resources. Our study was designed to determine if A. mellifera has a preference for exotic or native plants. We observed patches of exotic plants and patches of native plants and recorded the type of bee (exotic or native) that visited each flowering head. We also examined data from Kearns and Oliveras (unpublished), which illustrates that invasive plant species are also popular with native bees, and may draw vital pollinators away from native plants. Our results indicate that honeybees prefer to visit exotic invasive plant species to native plants. Consequently, honeybees may contribute to the spread of exotic plant species and the decline of native plant species, reducing biodiversity. Thus, native plants are doubly jeopardized. The invasion of exotic flora and fauna into native ecosystems on the plains of Colorado is part of a worldwide phenomenon of species invasion, and researchers must continue to investigate interspecies relationships to minimize the potential negative effects of invasive species.

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Invasive Plant Species: Consumer Awareness, Knowledge, and Expectations

HortScience ◽

10.21273/hortsci.40.4.1136a ◽

2005 ◽

Vol 40 (4) ◽

pp. 1136A-1136 ◽

Cited By ~ 1

Author(s):

Kathleen M. Kelley ◽

Janine R. Stumpf ◽

James C. Sellmer ◽

Ricky M. Bates

Keyword(s):

Plant Species ◽

Invasive Plant ◽

Native Plants ◽

Exotic Plants ◽

Invasive Plant Species ◽

Consumer Awareness ◽

Attitudes And Behaviors ◽

Potential Problems ◽

Survey Results ◽

Alternative Species

Consumers were surveyed at the 2004 Philadelphia Flower Show in Philadelphia, Pa. from 8–10 Mar., to quantify their attitudes and behaviors towards invasive plant species and the potential problems associated with purchasing and planting invasives in the landscape. A majority of the 341 participants (81.5%) was aware that non-native exotic plants were used in the landscape and that these plants may be invasive in natural areas. Less than half (40.1%) acknowledged owning plants that were considered invasive, while one-third (33.5%) did not know. Less than half (41.3%) believed that laws should be passed to prevent sale of non-native exotic plants, while 27.8% believed that laws should be passed to allow sale of only native plants in their area. Three distinct consumer segments were identified using cluster analysis: “Invasive savvy,” participants knowledgeable about invasives and interested in alternative species; “Invasive neutral,” participants neutral in their decision to purchasing alternatives to invasive plants and price sensitive in regard to paying more for plants tested for invasiveness; and “Invasive inactive,” participants opposed to purchasing genetically modified plants or those bred to be seedless. Survey results indicated that media sources (e.g., television and newspapers/magazines/books) would be effective for educating consumers about potential problems associated with invasive species in the landscape.

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