Combined flow cytometry and K-mer analysis for genome size estimation and genomic characterization of Schnabelia terniflora

doi:10.14088/j.cnki.issn0439-8114.2026.07.021

Abstract

Abstract: To further elucidate the genetic background of Schnabelia terniflora and promote the development of its genomic resources, flow cytometry was used to estimate the genome size of Schnabelia terniflora, with maize used as the reference plant. Meanwhile, the genome of Schnabelia terniflora was sequenced using the Illumina sequencing platform, and K-mer analysis was used to analyze the heterozygosity, GC content, and other genetic information of the Schnabelia terniflora genome, followed by NT alignment. The results showed that the genome size of Schnabelia terniflora estimated by flow cytometry was approximately 1 210 Mb. A total of 103.77 Gb of high-quality data was obtained using the Illumina sequencing platform, with an average sequencing depth of 73×. The genome size of Schnabelia terniflora was estimated to be approximately 1 220 Mb, with a heterozygosity rate of 1.18%, a GC content of 38.04%, and a repetitive sequence proportion of 80.20%. A comparison revealed that the genome size estimated by K-mer analysis was basically consistent with the results detected by flow cytometry. In addition, according to the NT database alignment results, among all species with known sequences, the sequencing reads of Schnabelia terniflora showed the highest matching rate with Scutellaria galericulata (17.82%), followed by Schnabelia terniflora itself (10.44%), Ballota nigra (4.77%), Schnabelia oligophylla (3.24%), and other plants. The genome of Schnabelia terniflora exhibited relatively low heterozygosity and a high proportion of repetitive sequences.

Key words: Schnabelia terniflora, flow cytometry, K-mer analysis, genome size, medicinal plant

CLC Number:

Q949.777.6

DENG Yu-jie, ZHANG Ze-zhi, YOU Lei, ZHANG Yong-hong, ZHENG Lan-lan. Combined flow cytometry and K-mer analysis for genome size estimation and genomic characterization of Schnabelia terniflora[J]. HUBEI AGRICULTURAL SCIENCES, 2026, 65(7): 133-139.

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