Abstract Detail

Population Genetics/Genomics

Gomez Quijano, Maria Jose [1], Etterson, Julie [2], Gross, Briana [1].

Why do Coastal Seeds Fail? A Population genetics and phenotypic analysis of coastal and non-coastal Northern red oak in Minnesota.

The North Shore region in northern Minnesota has a unique climate moderated by Lake Superior, resulting in warmer winters, a reduced risk of spring frost, cooler summers, and an extended fall season. Observations show that coastal seeds from different tree species such as northern red oak (Quercus rubra) fail to become established when they are planted in inland areas, which has led to the avoidance of coastal seed collections. Poor performance of coastal seed sources in inland climates suggest that these populations may be genetically differentiated. Alternatively, the failure to establish could be driven by environmental carryover from the maternal tree’s environment that influences gene regulation with maladaptive outcomes in a non-local climate. To explore possible explanations for the poor performance of coastal seeds, we combined neutral molecular markers and a common garden experiment to examine population differentiation corresponding to distance from the lake. We used restriction site associated DNA sequencing (RAD-seq) to identify single nucleotide polymorphisms (SNPs) and examine population structure in Q. rubra populations at three categorical distances from Lake Superior (coastal, inland, and interior). To examine phenotypic differentiation, we collected acorns and planted them in a fully randomized block design in the greenhouse, where germination and juvenile traits were measured for a full season. Despite the geographical distance between our populations (max = 156.75km, we found no molecular differentiation among populations. With respect to phenotype, coastal populations had significantly lighter seeds, earlier germination dates and higher germination rates than non-coastal populations. Our results suggest that while the Q. rubra populations are not differentiated at neutral genetic markers, the populations do differ for key traits which may be associated with traits under natural selection, environmental carryover effects, or genotype by environment interactions.

1 - University Of Minnesota Duluth, Department Of Biology, 207 Swenson Science Building, 1035 Kirby Drive, Duluth, MN, 55812, United States
2 - University Of Minnesota Duluth, 207 Swenson Science Building, 1110 Kirby Drive, 6770 Haugen Lane, 1035 Kirby Drive, Duluth, MN, 55803, United States

Keywords:
quercus
population genetics
quantitative genetics
RAD-seq
common garden.

Presentation Type: Oral Paper
Session: POPGEN1, Population Genetics/Genomics I
Location: Virtual/Virtual
Date: Tuesday, July 28th, 2020
Time: 3:15 PM
Number: POPGEN1002
Abstract ID:572
Candidate for Awards:Margaret Menzel Award