title: Effects of inflorescence stem structure and cell wall components on the mechanical strength of inflorescence stem in herbaceous peony.
abstract: Herbaceous peony (Paeonia lactiflora Pall.) is a traditional famous flower, but its poor inflorescence stem quality seriously constrains the development of the cut flower. Mechanical strength is an important characteristic of stems, which not only affects plant lodging, but also plays an important role in stem bend or break. In this paper, the mechanical strength, morphological indices and microstructure of P. lactiflora development inflorescence stems were measured and observed. The results showed that the mechanical strength of inflorescence stems gradually increased, and that the diameter of inflorescence stem was a direct indicator in estimating mechanical strength. Simultaneously, with the development of inflorescence stem, the number of vascular bundles increased, the vascular bundle was arranged more densely, the sclerenchyma cell wall thickened, and the proportion of vascular bundle and pith also increased. On this basis, cellulose and lignin contents were determined, PlCesA3, PlCesA6 and PlCCoAOMT were isolated and their expression patterns were examined including PlPAL. The results showed that cellulose was not strictly correlated with the mechanical strength of inflorescence stem, and lignin had a significant impact on it. In addition, PlCesA3 and PlCesA6 were not key members in cellulose synthesis of P. lactiflora and their functions were also different, but PlPAL and PlCCoAOMT regulated the lignin synthesis of P. lactiflora. These data indicated that PlPAL and PlCCoAOMT could be applied to improve the mechanical strength of P. lactiflora inflorescence stem in genetic engineering.
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.|Jiangsu Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou 225009, China.
authors.forename: Daqiu
authors.initials: D
authors.lastname: Zhao
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.
authors.forename: Chenxia
authors.initials: C
authors.lastname: Han
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.|Jiangsu Key Laboratory of Crop Genetics and Physiology, Yangzhou University, Yangzhou 225009, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Tao
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.
authors.forename: Zhaojun
authors.initials: Z
authors.lastname: Hao
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.
authors.forename: Qingping
authors.initials: Q
authors.lastname: Geng
authors.affiliation: College of Horticulture and Plant Protection, Yangzhou University, Yangzhou 225009, China.
authors.forename: Bei
authors.initials: B
authors.lastname: Du
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002473:Cell Wall / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D002482:Cellulose / Q000378:metabolism; D015870:Gene Expression; D018506:Gene Expression Regulation, Plant; D056626:Inflorescence / Q000166:cytology / Q000502:physiology*; D008031:Lignin / Q000096:biosynthesis; D008969:Molecular Sequence Data; D029596:Paeonia / Q000033:anatomy & histology / Q000166:cytology / Q000502:physiology*; D018547:Plant Stems / Q000033:anatomy & histology / Q000166:cytology / Q000502:physiology*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013718:Tensile Strength / Q000502:physiology*
chemical_list: D002482:Cellulose; D008031:Lignin