Xiao Gong

Idesia polycarpa from Sichuan is a valuable germplasm with high economic potential, but it faces variety scarcity. To address this, this study collected 16 varieties (lines), identifying IpHT1 as a promising parent due to its high oil content (38.5%) and red fruits. Polyploid induction via adding 0.50% colchicine to Murashige and Skoog (MS) medium yielded 520 IpHT1 mutagenized seedlings. Subsequently, flow cytometry (FCM) was performed on 401 morphologically variant seedlings which had been initially screened, resulting in the identification of 15 suspected triploids, 35 suspected tetraploids, and 3 chimeras. Furthermore, fluorescence in situ hybridization (FISH) analysis found that the probe (AG₃T₃)₃ had terminal signals at both ends of each chromosome, allowing for the counting of 42 chromosomes in diploids and 84 in tetraploids. The probe 5S rDNA showed 2, 3, and 4 hybridization signals in the interphase nuclei of diploid, triploid, and tetraploid cells, respectively, but the probe (GAA)₆ failed to produce any signal on I. polycarpa chromosomes. Ultimately, 18 polyploids were selected, including 7 triploids and 11 tetraploids. Triploids and tetraploids showed significant leaf morphological and physiological differences from diploids. Consequently, this study successfully established a polyploid breeding system for I. polycarpa, thereby enhancing its genetic diversity and breeding potential.

This study was conducted to evaluate the 5S rDNA site number, position, and origin of signal pattern diversity in 42 plant species using fluorescence in situ hybridization. The species were selected based on the discovery of karyotype rearrangement, or because 5S rDNA had not yet been explored the species. The chromosome number varied from 14 to 160, and the chromosome length ranged from 0.63 to 6.88 μm, with 21 species having small chromosomes (<3 μm). The chromosome numbers of three species and the 5S rDNA loci of nineteen species are reported for the first time. Six 5S rDNA signal pattern types were identified. The 5S rDNA varied and was abundant in signal site numbers (2–18), positions (distal, proximal, outside of chromosome arms), and even in signal intensity. Variation in the numbers and locations of 5S rDNA was observed in 20 species, whereas an extensive stable number and location of 5S rDNA was found in 22 species. The potential origin of the signal pattern diversity was proposed and discussed. These data characterized the variability of 5S rDNA within the karyotypes of the 42 species that exhibited chromosomal rearrangements and provided anchor points for genetic physical maps.

Illicium verum Hook. f. is a globally significant spice, which is recognized in China as a food-medicine homolog and extensively utilized across the pharmaceutical, food, and spice industries. China boasts the world’s leading resources of I. verum, yet its comprehensive utilization remains relatively underexplored. Through a resource survey of I. verum and the application of bibliometric visualization using CiteSpace, this study analyzed 324 papers published in the Web of Science Core Collection (WOSCC) from 1962 to 2023 and 353 core documents from China’s three major databases (CNKI, Wanfang Database, and VIP Database). I. verum from Guangxi province towards various southern provinces in China, with autumn fruits exhibited superior quality and market value over their spring fruits. Literature in WOSCC emerged earlier, with a research emphasis on food science technology and pharmacology pharmacy domains. WOSCC research on I. verum could be divided into two phases: an embryonic period (1962–2001) and a growth period (2002–2023), showing an overall upward trend in publication. The three major Chinese databases contain a larger number of publications, with a focus on the food sector, which could be categorized into three stages: an embryonic period (1990–1999), a growth period (2000–2010), and a stable period (2011–2023), with an overall downward trend in publication. Both Chinese and international research hotspots converge on the medical applications of I. verum, with antioxidant bioactivity research emerging as a prevailing trend. This study delineated the resource distribution of I. verum across China and identified the research hotspots and trends both in China and internationally. The findings are beneficial for guiding researchers in swiftly establishing their research focus and furnishing decision-makers with a comprehensive reference for industry information.

5S rDNA is essential component of all cell types. A survey was conducted to study the 5S rDNA site number, position, and origin of signal pattern diversity in 64 plants using fluorescence in situ hybridization. The species used for this experiment were chosen due to the discovery of karyotype rearrangement, and for species checked in which 5S rDNA has not yet been explored. The chromosome number was 14–160, while the chromosome length was 0.63–6.88 μm, with 37 plants (58%) had small chromosome (<3 μm). The chromosome numbers of three species and 5S rDNA loci of 19 species have been reported for the first time. 5S rDNA was varied and abundant in signal site number (2–18), position (e.g., interstitial, distal, and proximal position, occasionally, outside chromosome), and even as intense (e.g., strong, weak, and slight). Our results exposed modifiability in the number and location of 5S rDNA in 33 plants and demonstrated an extensive stable number and location of 5S rDNA in 31 plants. The potential origin of signal pattern diversity was probably caused by chromosome rearrangement (e.g., deletion, duplication, inversion, translocation), polyploidization, self-incompatibility, and chromosome satellites. These data characterized the variability of 5S rDNA within the karyotypes of the 64 plants that exhibited massive chromosomal rearrangements and provided anchor points for genetic physical maps. These data prove the utility of the 5S rDNA oligonucleotide as a chromosome marker in identifying plant chromosomes. This method provides a basis for developing similar applications for cytogenetic analysis in other species. Article Summary: A survey was exploited to study 5S rDNA signal pattern diversity in 64 plants by FISH. The chromosome number of three species and 5S rDNA loci of 19 species have been reported by the first time. 5S rDNA was really rather various and abundant in signal site number (2–18), position (interstitial, distal, proximal position, occasionally, outside chromosome), even as the intense (strong, week, slight). These data prove the utility of 5S rDNA oligonucleotide as chromosome marker in identifying plant chromosomes.

Data for the chromosomal FISH mapping localization of (AG₃T₃)₃ are compiled for 37 species belonging 27 families; for 24 species and 14 families, this is the first such report. The chromosome number and length ranged from 14–136 and 0.56–14.48 μm, respectively. A total of 23 woody plants presented chromosome length less than 3 μm, thus belonging to the small chromosome group. Telomeric signals were observed at each chromosome terminus in 38 plants (90.5%) and were absent at several chromosome termini in only four woody plants (9.5%). Non-telomeric signals were observed in the chromosomes of 23 plants (54.8%); in particular, abundant non-telomeric (AG₃T₃)₃ was obviously observed in Chimonanthus campanulatus. Telomeric signals outside of the chromosome were observed in 11 woody plants (26.2%). Overall, ten (AG₃T₃)₃ signal pattern types were determined, indicating the complex genome architecture of the 37 considered species. The variation in signal pattern was likely due to chromosome deletion, duplication, inversion, and translocation. In addition, large primary constriction was observed in some species, probably due to or leading to chromosome breakage and the formation of new chromosomes. The presented results will guide further research focused on determining the chromosome number and disclosing chromosome rearrangements of woody plants.