Progress 10/01/01 to 09/30/04
Outputs
We have completed our exploration of molecular assays as a measure of agricultural impact to amphibian populations breeding in farm ponds. Our efforts to develop the AFLP analyses met with some unexpected difficulties, forcing us to focus on two of the four species we had originally proposed. We found that for those two species of common frogs, the patterns of genetic distribution vary in traditional and organic farms, but that the impact of farming alone is sufficient to alter the geographic distribution of genetic diversity. Our findings are corroborated by a recently published paper (Gustafson et al., 2001, J. Environmental Management) demonstrating that amphibian populations are highly sensitive to land use changes, and therefore the primary disturbance (modification of land for agriculture) has more impact than the choice of agricultural procedures, as measured by the populations breeding in farm ponds. Our results have led us to explore other changes in frogs,
such as increased susceptibility to disease and changes in reproductive function, that might serve as better indicators of the relative impact of different farming practices on natural populations. Using our pilot data, my lab has submitted a proposal to the New York State Biodiversity Research Institute to continue work on this system.
Impacts
An objective assay for the genetic consequences of farming practices on amphibian populations will help define the thresholds for impact on these species. Our expectation is that populations breeding in ponds that receive runoff from pesticide application in traditional farms will have the genetic signature of bottlenecked populations. If these expectations are met, our assay will enable an independent test for the environmental benefits of practices that reduce application of pesticides to crops.
Publications
- No publications reported this period
|
Progress 01/01/03 to 12/31/03
Outputs
The goal of our Hatch grant is to develop a molecular assay that can be used to determine the impact of traditional and organic farming on amphibian populations breeding in farm ponds. During the past year we have developed and optimized the molecular protocols for applying AFLP analyses in tadpoles of 4 different species, and began collections of tadpoles from ponds that are found on organic and traditional farms. We encountered some difficulties when comparing genetic diversity from various species; primarily because in our AFLP analyses our primer combination that yielded reliable amplification of 30-50 bands (the target number for comparisons among populations) did not work equally well for all species. We are working further on this fine-tune the laboratory protocols and should have them worked out in the next few months. During the next breeding season (Feb/March) we will perform the bulk of the collections and test the generality of this molecular assay of
amphibian population health.
Impacts
An objective assay for the genetic consequences of farming practices on amphibian populations will help define the thresholds for impact on these species. Our expectation is that populations breeding in ponds that receive runoff from pesticide application in traditional farms will have the genetic signature of bottlenecked populations. If these expectations are met, our assay will enable an independent test for the environmental benefits of practices that reduce application of pesticides to crops.
Publications
- No publications reported this period
|
Progress 01/01/02 to 12/31/02
Outputs
The goal of our Hatch grant is to develop a molecular assay that can be used to determine the impact of traditional and organic farming on amphibian populations breeding in farm ponds. During the past year we have developed and optimized the molecular protocols for applying AFLP analyses in tadpoles of 4 different species, and began collections of tadpoles from ponds that are found on organic and traditional farms. In a preliminary sampling, we collected tadpole samples from 6 ponds and used the 4 species collected at these sites to develop the molecular assay for genetic heterogeneity, using amplified fragment length polymorphism (AFLP). AFLP analyses works well for all 4 species tested and after extensive optimization we found a primer combination that yielded reliable amplification of 30-50 bands (the target number for comparisons among populations). The laboratory protocols are now in place. During the next breeding season we will focus on collecting larger
samples, to test the generality of this molecular assay of amphibian population health.
Impacts
An objective assay for the genetic consequences of farming practices on amphibian populations will help define the thresholds for impact on these species. Our expectation is that populations breeding in ponds that receive runoff from pesticide application in traditional farms will have the genetic signature of bottlenecked populations. If these expectations are met, our assay will enable an independent test for the environmental benefits of practices that reduce application of pesticides to crops.
Publications
- No publications reported this period
|
|