Research Report 2019_20

AGRISCIENCE RESEARCH

Ada Stewart of the HudsonAlpha Genome Sequencing Center sequencing plant genomes such as wild and domestic variations of cotton and peanuts on the PacBio ® machines at HudsonAlpha.

For their study, the group sequenced and assem- bled reference-grade genomes for two major lineages of domesticated cotton and three pre-domestication wild species. Despite the wide geographic distribution and diversification, the wild and domesticated genomes turned out to be surprisingly similar. Domesticated cot- ton genomes retained much of the gene content and genomic diversity relative to the wild plants. While the group was surprised at the lack of diversity between wild and domesticated cotton, comparative analysis of the five cotton genomes did identify unique genes relat- ed to fiber and seed traits in two domesticated species. In addition, they found that wild cotton has more disease resistance triggers than domesticated cotton varieties, which tend to be more vulnerable. The lack of diversity means that researchers will not be able to reach back as easily into the wild cotton gene pool to introduce lost traits like disease resistance back into domesticated cotton plants. However, the en- tire team is confident that the newly assembled cotton genomes will lead to direct benefits for cotton producers and the cotton industry. The conceptual advances and genomic resources discovered in this study will help improve cotton fiber yield and quality.

continued on p.30 Reference genomes are also useful for tracing the evolutionary history of domesticated crops. Grimwood and Schmutz helped create a reference genome for Arachis hypogaea, the species of peanut that is grown in fields today 2 . A. hypogaea is the result of a natural cross between two wild species of peanut that were brought together by humans in South America.

DNA extraction is the first step to making a reference genome.

2019-20 Research Report 29

Made with FlippingBook - Online magazine maker