The effects of a myrmecochore-produced chemical on entomopathogenic fungal growth and seed-dispersing ant survival rates and foraging patterns.

Myrmecochory, a type of ant-mediated seed dispersal, is a diffuse, widespread mutualism in which both partners are purported to benefit from the services or rewards of the other. However, ant benefits in this interaction are conflicted and understudied, especially in the context of microbial third parties. Here, we investigate the effect of a myrmecochore plant-produced antimicrobial chemical (sanguinarine) on the growth of a common entomopathogenic fungus ().

Nest substrate, more than ant activity, drives fungal pathogen community dissimilarity in seed-dispersing ant nests.

Myrmecochory is a widespread mutualism in which plants benefit from seed dispersal services by ants. Ants might also be providing seeds with an additional byproduct benefit via reduced plant pathogen loads in the ant nest environment through their antimicrobial glandular secretions. We investigate this byproduct benefit by identifying fungal communities in ant nests and surrounding environments and quantifying fungal community change (1) through time, (2) between different nest substrates, and (3) as a function of average ant activity levels within nests (based on observed ant activity at nest entrances throughout the summer).

Effects of seed morphology and elaiosome chemical composition on attractiveness of five species to seed-dispersing ants.

Morphological and chemical attributes of diaspores in myrmecochorous plants have been shown to affect seed dispersal by ants, but the relative importance of these attributes in determining seed attractiveness and dispersal success is poorly understood. We explored whether differences in diaspore morphology, elaiosome fatty acids, or elaiosome phytochemical profiles explain the differential attractiveness of five species in the genus to eastern North American forest ants. Species were ranked from least to most attractive based on empirically-derived seed dispersal probabilities in our study system, and we compared diaspore traits to test our hypotheses that more attractive species will have larger diaspores, greater concentrations of elaiosome fatty acids, and distinct elaiosome phytochemistry compared to the less attractive species.

Overall seed dispersal effectiveness is lower in endemic Trillium species than in their widespread congeners.

Premise Of The Study: Comparing ecological attributes of endemic species with related, widespread species can reveal differences accounting for rarity. Forests of the southeastern United States are home to many range-restricted endemic and widespread species of Trillium, a genus of ant-dispersed herbs. Evidence suggests that aspects of seed-related life history stages are often correlated with plant rarity, but few studies have tested whether the process of seed dispersal differs for endemic and widespread species.

Pollen-mediated gene flow from transgenic to non-transgenic switchgrass (Panicum virgatum L.) in the field.

Background: Switchgrass is C perennial grass species that is being developed as a cellulosic bioenergy feedstock. It is wind-pollinated and considered to be an obligate outcrosser. Genetic engineering has been used to alter cell walls for more facile bioprocessing and biofuel yield.

Sensitivity of a real-time PCR method for the detection of transgenes in a mixture of transgenic and non-transgenic seeds of papaya (Carica papaya L.).

Background: Genetically engineered (GE) ringspot virus-resistant papaya cultivars 'Rainbow' and 'SunUp' have been grown in Hawai'i for over 10 years. In Hawai'i, the introduction of GE papayas into regions where non-GE cultivars are grown and where feral non-GE papayas exist have been accompanied with concerns associated with transgene flow. Of particular concern is the possibility of transgenic seeds being found in non-GE papaya fruits via cross-pollination.

Advances in biotechnology and genomics of switchgrass.

Switchgrass (Panicum virgatum L.) is a C4 perennial warm season grass indigenous to the North American tallgrass prairie. A number of its natural and agronomic traits, including adaptation to a wide geographical distribution, low nutrient requirements and production costs, high water use efficiency, high biomass potential, ease of harvesting, and potential for carbon storage, make it an attractive dedicated biomass crop for biofuel production.

Gene flow matters in switchgrass (Panicum virgatum L.), a potential widespread biofuel feedstock.

There currently exists a large push for the use, improvement, and expansion via landscape modification of dedicated biofuel crops (feedstocks) in the United States and in many parts of the world. Ecological concerns have been voiced because many biofuel feedstocks exhibit characteristics associated with invasiveness, and due to potential negative consequences of agronomic genes in native wild populations. Seed purity concerns for biofuel feedstock cultivars whose seeds would be harvested in agronomic fields also exist from the agribusiness sector.

Transgene introgression in crop relatives: molecular evidence and mitigation strategies.

Incorporation of crop genes into wild and weedy relative populations (i.e. introgression) has long been of interest to ecologists and weed scientists.

Native grasses as a management alternative on vegetated closure caps.

Capped waste sites often are vegetated with commercial turf grasses to increase evapotranspiration and prevent erosion and possible exposure of the barrier. Fertilizer, frequent watering, and mowing may be required to establish the turf grass and prevent invasion by trees and shrubs. Oldfield vegetation of grasses and forbs is a possible sustainable alternative to turf grass communities.

Cold temperature increases winter fruit removal rate of a bird-dispersed shrub.

We tested the hypothesis that winter removal rates of fruits of wax myrtle, Myrica cerifera, are higher in colder winters. Over a 9-year period, we monitored M. cerifera fruit crops in 13 0.