Abstract Detail

Population Genetics/Genomics

Lee, Soo-Rang [1], Ha, Young-Ho [2], Oh, Seung-Hwan [2].

Risk of genetic swamping in the progenitor of the domesticated apple (Malus sieversii) from the diversity hotspot, Tien Shan, Kazakhstan.

There is growing attention to gene flow between crops and the wild relatives as global landscapes have rapidly converted into agricultural farm fields over the past century. Coupled with the natural habitat degradation, crop to wild introgression may advance the extinction risks of rare plants through demographic swamping and/or genetic swamping. Malus sieversii, the progenitor of the apple, is exclusively distributed along Tien Shan mountains. Habitat fragmentation and hybridization between M. sieversii and the cultivated apples have been proposed to be the causal mechanism of the accelerated extinction risk. We examined the genetic diversity pattern of eleven apple populations (8 M. sieversii, 2 M. domestica and 1 M. niedzwetzkyana) and assessed the gene flow between M. sieversii and the cultivated apples in Kazakhstan using thirteen nuclear microsatellite loci. On average, apple populations harbored fairly high within-population diversity (He=0.76) in part due to inter- and intra- specific hybridization. In contrast, pairwise F_ST values (0.01-0.13) were very low suggesting long distance dispersal medicated by frugivorous animals and humans. Assignment results showed a split pattern between the cultivated and wild apples and frequent admixture among the apple populations. The level of gene flow estimated by migration rates appeared to be much higher in the historical measure than in the contemporary measure, which might infer the increased human intervention within the recent past. Our study highlighted the prevalent crop to wild gene flow of apples occurring in Kazakhstan proposing an accelerated risk of genetic swamping. 

1 - Korea National Arboretum , Division Of Forest Biodiversity, 415 Gwangneungsumokwon-ro, Soheul-eup , Pocheon, 41, 11186, Korea, Republic of
2 - Korea National Arboretum, Division of Forest Biodiversity

Keywords:
genetic diversity
gene flow
Apple
Tien Shan
Malus sieversii
Migration rate.

Presentation Type: Poster
Session: P, Population Genetics/Genomics Posters
Location: Virtual/Virtual
Date: Thursday, July 30th, 2020
Time: 5:00 PM Time and date to be determined
Number: PPG007
Abstract ID:561
Candidate for Awards:None