Genetic Diversity of Brassica Species Revealed by Amplified Fragment Length Polymorphism and Simple Sequence Repeat Markers

Maoteng Li,Chunyu Zhang,Wei Qian,Jinling Meng 한국원예학회 2007 Horticulture, Environment, and Biotechnology Vol.48 No.1

Amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers were employed for assessing the genetic diversity of 21 Brassica cultivars including three oilseed species, B. rapa, B. carinata, and B. napus. Nineteen AFLP primer pairs generated an average of 83.05 with 78.95 polymorphic bands (95.05% of polymorphism) and 19 SSR primer pairs produced an average of 11.16 allelic products with 10.74 polymorphic products (91.50% of polymorphism). The dendrogram showed that the three species can be clearly distinguished and every two B. rapa cultivars was with the most abundant genetic diversity. The similarity matrixes detected by two-way Mantel test showed that the matrix correlation between the data from 19 AFLP and 19 SSR primer pairs showed a good fit, which revealed that the AFLP and SSR markers were all good for assessing the genetic diversity of Brassica species. However, the AFLP markers had slightly higher resolution of genetic similarities than the SSR markers.

The Production and Cytological Analysis of Brassica napus -B Genome Chromosome Monosomic Addition Lines and Their Hybrids

Li Maoteng,Xiang Jun,Liu Jianmin,Yu Longjiang,Li Dianrong 한국유전학회 2008 Genes & Genomics Vol.30 No.2

The Brassica napus-B genome monosomic addition lines (MALs) (AACC + B’, 2n = 39) were developed from self-pollination of pentaploid hybrids (AABCC) that were derived from hybridization between hexaploid hybrids (AABBCC) and B. napus (AACC). The alien chromosomes of the B genome in MALs were identified by the GISH technique, by observation of the meiotic behavior of pollen mother cells (PMCs), and by B-genome-specific molecular marker analysis. Studies of the meiotic behavior of B. napus-B genome chromosome MALs at diakinesis revealed that the majority of the chromosome configuration was 19²+1¹, which indicated that the alien B genome chromosome remained univalent in most cases. The laggard-free PMCs also appeared at a lower ratio, which indicated that the B genome chromosome could be transmitted into gametes. The chromosome configurations of 20² and 19²+2¹ that appeared in double MALs (AACC+ 2 chromosomes of the B genome) indicated different homoeology between different B genome chromosomes. The paired B genome bivalent in double MALs can be normally segregated at anaphase in most cases. PMCs with multivalents were observed in all the double MAL combinations, which indicated homology of the B genome chromosomes with the A or C genome chromosomes. The Brassica napus-B genome monosomic addition lines (MALs) (AACC + B’, 2n = 39) were developed from self-pollination of pentaploid hybrids (AABCC) that were derived from hybridization between hexaploid hybrids (AABBCC) and B. napus (AACC). The alien chromosomes of the B genome in MALs were identified by the GISH technique, by observation of the meiotic behavior of pollen mother cells (PMCs), and by B-genome-specific molecular marker analysis. Studies of the meiotic behavior of B. napus-B genome chromosome MALs at diakinesis revealed that the majority of the chromosome configuration was 19²+1¹, which indicated that the alien B genome chromosome remained univalent in most cases. The laggard-free PMCs also appeared at a lower ratio, which indicated that the B genome chromosome could be transmitted into gametes. The chromosome configurations of 20² and 19²+2¹ that appeared in double MALs (AACC+ 2 chromosomes of the B genome) indicated different homoeology between different B genome chromosomes. The paired B genome bivalent in double MALs can be normally segregated at anaphase in most cases. PMCs with multivalents were observed in all the double MAL combinations, which indicated homology of the B genome chromosomes with the A or C genome chromosomes.

Transcriptionally and Phylogenetically Analyzing the P Protein Gene of Glycine Decarboxylase for Understanding the Evolution of C_3-C_4 Species in Brassicaceae

Chunyu Zhang,박인애,Fangsen Xu,Maoteng Li,임용표,Jinling Meng 한국원예학회 2011 Horticulture, Environment, and Biotechnology Vol.52 No.4

Lacking P protein of glycine decarboxylase (GDCP) from the mesophyll cells was one of the major steps for C_3species to evolve into C_3-C_4 species. Previous studies indicated that the lack of P protein in the mesophyll cells of C_3-C_4species of Flaveria is regulated by gene different transcription. In the family of Brassicaceae, most plants show a typical C_3photosynthetic characteristic, which includes some important vegetables and oil crops, while few plants in this family exhibit a C_3-C_4 type of character. To understand the mechanism of difference in distribution of P protein between the 2 different photosynthetic types, a C_3 type of 1.6 kb BnGDCP promoter from Brassica napus was used for detailed analysis in this study. This promoter exhibited the ability to drive beta-glucuronidase gene (GUS) expression in both mesophyll and the bundle sheath cells of C_3 species, Arabidopsis. However, the same promoter was also found to drive GUS expression in both the mesophyll and bundle sheath cells of a typical of C_3-C_4 species such as Moricandia arvensis, which loses the P protein from the mesophyll cells. This implies that in absence of P protein from the mesophyll cells of Moricandia (C_3-C_4 species) may be regulated by differential transcription of the P protein gene as well. And then, a region, which determines a mesophyll cells specific expression, was narrowed down to 135 bp in length through detailed promoter/reporter gene assay. DNA sequences alignment of the 5′-flanking sequences from either a C3 or C_3-C_4 species in Brassicaceae indicated that 2 different nucleotide acids only conserved to C_3 species were revealed. Phylogenetic analysis of those 5′-flanking sequences of GDCP indicated that C_3-C_4 species in the genus of Moricandia might have been evolved from different C_3 ancestors; interestingly, a C_3-C_4species, D. tenuifolia, was indicated to have shared common ancestors with the C_3-C_4 species, M. spinosa, and the C_3 species M. foleyii in Moricandia.

Anatomical Adaptations of the Xerophilous Medicinal Plant, Capparis spinosa, to Drought Conditions

Lu Gan,Chunyu Zhang,Yongtai Yin,Zhiwei Lin,Yongwei Huang,Jun Xiang,Chunhua Fu,Maoteng Li 한국원예학회 2013 Horticulture, Environment, and Biotechnology Vol.54 No.2

Capparis spinosa is a plant that grows in dry and arid environments. As far as can be ascertained, no comprehensive studies on how the leaf, stem and root structures adapt to drought conditions have been published to date. In this paper, a study into the anatomical adaptations of the leaf, stem and root of C. spinosa to drought environments was conducted using in vitro cultured seedlings as control. The results showed that C. spinosa could change its leaf, stem, and root structures when adapting to drought conditions. The plant growing under drought conditions possessed an enlarged transit region between the stem and root where the xylem and fibro-vascular system had increased in order to enhance water absorption and storage capacity. The leaf, stem and root of C. spinosa under drought conditions were better developed than those under normal in vitro culture conditions. The leaf possessed uniform mesophyll cells and three or four layers of palisade mesophyll cells on both sides of the mature leaves. The stomata were evenly distributed across both sides of the leaf, and they remained open continually during the day throughout the summer growing period, especially those on the lower leaf surface. The xylem in the stem was extremely well developed with wide vessels and much thicker cortical layers. All these characteristics can enhance the adaptability of C. spinosa and enable it to survive in extremely dry and arid areas.