Regional Genetic Diversity

Background and Introduction

Restoration along the northern Gulf Coast remains exceedingly important due to impacts from recent natural and anthropogenic disasters. Hurricanes, including Ivan, Rita, and particularly Katrina (in 2004, 2005 and 2005, respectively) have severely eroded barrier islands and coastal marshlands. Katrina alone is documented to have heavily impacted barrier islands, and converted as much as one quarter of coastal marsh to open water in areas that were closely studied. Manmade disturbance has also generated substantial losses in coastal marsh habitat. For example, the Deepwater Horizon oil spill of 2010 oiled approximately 75 km of the Gulf Coast, and it is believed that the synergy between that disaster with other natural and anthropogenic impacts has resulted in extensive coastal marsh erosion. Coastal restoration initiatives since 2005 include the Post-Katrina MS Governor’s $7.5 billion plan (CRS 2006) , the post-2010 BP oil spill recovery and remediation strategies, the 2013 Draft Initial Comprehensive Plan: Restoring the Gulf Coast’s Ecosystem and Economy (www.restorethegulf.gov/); the GoCoast2020 initiative (www.gocoast2020.com/); and the NFWF Environmental Benefit Fund (http://www.nfwf.org).

All plans from these various restoration projects are regionally comprehensive with numerous current and future restoration activities, including barrier island and wetland vegetation. In Mississippi alone, approximately 30,000 acres in the three coastal counties have been allocated for restoration projects. Of these 30,000 acres, over 85% will include restoration of emergent aquatic vegetation with an estimated 5000 plants per acre at a cost of $1.25 each, over $150 million could be allocated back into the Mississippi economy. With these large regional scale restoration plans in progress, a considerable unmet demand for plant materials exists in Mississippi. Obtaining plants from out-of-state nurseries results in increased shipping times and costs as well as possible introduction of diseases and invasive species. All these factors contribute to reduced plant survival and decreased funds available for other restoration activities.

Prior to this research, significant genetic diversity was found in smooth cordgrass populations by Utomo et al. (2009). A series of studies at Louisiana State University funded by USDA-CSREES on smooth cordgrass (Spartina alterniflora) was limited to Louisiana, and all of the genetic work was limited to four wild populations from the upper basins in Louisiana. To date no similar research has been done on the dominant marsh plant species found in Mississippi, the black needlerush (Juncus roemerianus). Therefore, we propose to identify S. alterniflora and J. roemerianus stock from native accessions with signatures of genetic variation that are likely to hasten and increase the probability of successful restoration/remediation in compromised Gulf Coast habitats. To do so, we plan to obtain material from a much wider geographic area, using more modern fingerprinting techniques that will allow us to determine genetic diversity among and between a greater number of populations than has been done in prior published studies. We also plan to release germplasm lines to end-users for commercial propagation and deployment to restoration projects as needed. Knowing the genetic makeup of various individuals in the various populations will allow restoration projects to be composed of appropriate assemblages (both number and type) of germplasm lines; not only from a specific area, but we will be able to select a composition of several lines that when planted together have high fecundity of seed.

However, there are presently no readily available sources of native coastal and wetland plants within the state of Mississippi. The Center for Plant Restoration (CPR) at GCRL is growing plants only from native seeds to avoid genetic problems that could arise from interbreeding the genetic stock of Mississippi with other (e.g., Florida or Louisiana) plant sources. More information is needed about the genetic diversity of the species in MS and how compatible out-of-state plants are for use in local projects. This information and certified plant stock needs to be provided to local restoration and plant nursery businesses to improve access of the appropriate plant material for restoration within MS.

The objective of this amended Tidelands project (USM/FY16-M648-27) is to provide funding for research activities performed by the Coastal Mississippi Plant Consortium, a public-private cooperative for Mississippi coastal plant restoration that meets state requirements and regulations. The objective of the Consortium is to provide information and materials to establish and increase opportunities for the Mississippi nursery community and enhance applied and basic research to support commercial activity. Materials grown by Consortium members will improve the availability of plants for coastal habitat restoration activities, including RESTORE, living shorelines and beneficial use projects.

Specific Project Objectives:

(1) To determine and characterize genetic diversity among S. alterniflora and J. roemerianus populations along the Mississippi Gulf Coast.

(2) To use this information to synthesize appropriate assemblages of genetically diverse individuals that have higher seed production and future adaptability.

(3) To relay this information and disburse these lines for deployment in restoration projects to commercial propagators/end-users.

A research project of the Center for Plant Restoration and Coastal Plant Research - https://sites.google.com/site/coastalplantrestoration/

Spartina alterniflora seeds and seedlings growing in the Center for Plant Restoration greenhouse.