Abstract Detail

Ecology

Choi, Jiyeong [1], Mincey, Katherine [2], Boyd, Robert Steven [3].

Nickel concentrations of the high-Ni insect Melanotrichus boydi, a specialist on the Ni hyperaccumulator plant Streptanthus polygaloides (Brassicaceae).

The Ni hyperaccumulator Streptanthus polygaloides (Brassicaceae) is an annual herb endemic to the California Sierra Nevada mountain range. It consists of four morphotypes: yellow (Y), purple (P), yellow/purple (Y/P) and undulate (U). These morphotypes vary in sepal color, morphology and geographic location. This plant hyperaccumulates Ni from the soil at concentrations that vary depending on the morphotype. The high-Ni specialist insect Melanotrichus boydi (Hemiptera: Miridae) feeds on S. polygaloides via cellular disruption. This study compares Ni concentrations of M. boydi to other hemipterans collected from S. polygaloides plants. We also examined Ni concentrations of M. boydi to determine if insects collected from different host plant morphs varied significantly. We collected M. boydi specimens that were feeding on the four morphotypes of S. polygaloides. Additionally, non-Ni hemipteran herbivores were collected from some sites to compare the whole-body Ni concentrations of those hemipterans to M. boydi collected from the same sites. We used Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) to analyze whole-body Ni concentrations of individual insects. Nickel concentrations of M. boydi (mean: 672 µg Ni/g) were more than 16-fold higher Ni than those of other hemipteran herbivores (mean: 38 µg Ni/g). In addition, one-way ANOVA revealed that Ni concentrations of M. boydi differed significantly depending on their host S. polygaloides morphotype. M. boydi from U morphotype plants had significantly greater Ni concentrations (1436 µg Ni/g) than M. boydi from P (486 µg Ni/g), Y/P (587 µg Ni/g) or Y (611 µg Ni/g) morphotypes. However, Ni concentrations of M. boydi from P, Y/P, and Y morphotypes did not significantly differ from each other. We conclude that M. boydi contain significantly more Ni than other hemipterans collected from S. polygaloides, confirming its status as a high-Ni insect species. In addition, concentrations of Ni in M. boydi differ due to their morphotype host. Future studies will explore Ni concentrations in the different morphotype hosts to determine their correlation with Ni concentrations in M. boydi.

1 - Auburn University, Biological Sciences, 101 Rouse Life Science , Auburn, AL, 36830, USA
2 - Auburn University, 1309 Gatewood Dr #1102, Auburn, AL - Alabama, 36830, United States
3 - Auburn University, Department Of Biological Sciences, 101 ROUSE LIFE SCIENCES BLDG, AUBURN UNIVERSITY, AL, 36849-5407, USA

Keywords:
hyperaccumulation
Serpentine
Streptanthus polygaloides
Melanotrichus boydi.

Presentation Type: Poster
Session: P, Ecology Section Posters
Location: Exhibit Hall/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 5:30 PM This poster will be presented at 6:15 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PEC032
Abstract ID:744
Candidate for Awards:Ecological Section Best Undergraduate Presentation Award