DNA Barcoding Case Studies

Sitemap | text size +/−

Submitted By

Title & Categories

Scope

Taxon based DNA identification study in the flowering plant family Lauraceae. Preliminary exploratory research will be limited to species present in the CTFS Neotropical lowland forest research plots LTER plots in the region. Further expansion to Neotropical montane forests and paleotropical forest research plots in Southesat Asia is envisioned.  Material will be newly collected in Silica gel with vouchers from ca. 160 species ca. 50% of which are unidentified. At least two individuals from each “species” will be sampled. Plant DNA Barcode regions will be sequenced in accordance with the “Barcoding of Life Plant Working Group” guidelines. Initial exploratory phase will last 18 months. 

Purpose

Lauraceae are a large family of flowering of plants with ca. 2,750 species in 52 genera. The family is notorious among field botanists. Identification of genera and species is extremely difficult without flowering and fruiting material. One of the striking characteristics of Neotropical Lauraceae is that species almost identical in leaf characters can differ profoundly in floral or fruiting morphology, both within and between genera. Another serious problem in identifying Neotropical Lauraceae is that vegetative characters often vary considerably within species, populations, and even individuals (Burger 1988). Different collections of the same species have been described in different genera, even by the same specialist. This confusion represents a major stumbling block to understanding tropical plant life because an increasing proportion of what is known about tropical plant ecology comes from permanent tree plots where by necessity a large proportion of plants are identified on the basis of leaf characters in just a few, or even one, individual. 

Background

The "laboratorio de Botanica y Sistematica" of the University of the Andes in Bogota, Colombia has been one of the most active Barcioding labs in the region. Together with ten other institutions worldwide and led by The Royal botanic Gardens, Kew it has been involved in the development of a standard plant DNA barcode region. The PI, Santiago Madrinan is a Lauraceae taxonomists. 

Logistics

We are proposing to do a pilot study to test the feasibility of our approach and of the genetic markers. The budget requested is for specimen collection at three sites in the North West Amazon; 225 species will be sampled (ca.  100 spp. at Yasun and Amacayacu, and ca. 25 spp. at Los Amigos, in accordance with census data at each site), with two specimens for each species. Four herbarium vouchers will be made (one for the site’s herbarium, one for a major herbarium at each country, and two for the herbarium at the Universidad de los Andes, one of which will later be deposited at MO), plus a leaf sample in Silica gel. Shipping and handling of specimens to Colombia is included. Laboratory supplies for DNA extraction, amplification of four genetic regions for each of the 250 samples, and sequencing double strands of these two regions, for a total of ca. 1000 sequences. A technician in Bogot will extract total DNA, and amplify and sequence the proposed regions. The PI and a selected group of graduate students will travel to the sites to obtain ecological and morphological data of the specimens sampled for species identification. The PI and two graduate students will travel to Missouri Botanical Garden to match specimens with the extensive expert identified collection held at the herbarium 

Updates