Abstract Detail


Shen, Fengjiao [1], Bai, Xiaoxia [2], Cui, Mengwei [1], Shi, Shuo [1], Li, Lin [1], Li, Zhibin [2], Zhao, Jiancheng [3].

Identification of 17 Chinese Rhododendron cultivars: A Preliminary Study Based on DNA Barcodes and Leaf Epidermis Microscopic Characteristics.

Rhododendron is a group of famous ornamental plants. The horticulturalists usually divides genus Rhododendron L. into "Rhododendron" and "Azalea".Rhododendronsare regarded as the "boutique" of Rhododendron L. However, the first problem of research, development, and use of the cultivated plant is identification.There are few studies on the identification of Rhododendroncultivars.The traditionalidentification method depends on the flowering period,which is limited by the growth stage; thus, the accurate identification of Rhododendroncultivars at the non-flowering stage is the most significant difficulty.In this study, the DNA barcoding technique, and leaf epidermis microscopic characteristics analysis were applied to the study oftheidentification of 17cultivars, 71 individualsof Rhododendrons. The results showed: 1. The use of DNA barcodescan classify Rhododendron cultivars. Sequence psbA-trnHhadthe highest resolution in the alternative four DNA barcodes(ITS, matK, psbA-trnH, rbcL),and the resolution of new primer "matK"was higher than the resolution of ITS and rbcL. When using the two-genes combination, the psbA-trnH+matK resolution was higher than that of the single gene and other combinations. There was no significant difference in the results of joint tree-building with three genes and four genes. Therefore, using psbA-trnH+matK joint analysis for the identification of Rhododendron cultivars was suggested. 2. In this study, the leaf epidermis shape, vertical wall pattern, stomatal size, and stomatal density in the epidermis microstructures of Rhododendron cultivars were studied. There was a significant difference in the epidermis microstructure among different cultivars. Therefore, the leaf epidermis microstructureswere presumed couldbe used in the identification of Rhododendron cultivars. Also, the leaf epidermis morphology and DNA barcode sequences of 17Rhododendron cultivars were described in detail, which provided references for future identification of Rhododendron cultivars. 3. Synthesizing the above analytical methods and results, the DNA barcodes combined with the leaf epidermis microstructure features can accurately identify 17Rhododendron cultivars. To summarize, the DNA barcodes combined with the leaf epidermis microstructure features is a new idea and method for accurately identify the cultivars of Rhododendron.There are fiveadvantages:1) Identification is not limited by the growth stage and can be performed regardless of the flower; 2) Less material needed to avoid damage to the precious plant; 3) Easy to operate, the process does not depend on the participation of experts; 4) Better repeatability, identification results are relatively stable and objective; 5) Save time and low cost. Furthermore,a similar method can probablybe used in the identification of the cultivars of other taxa.

1 - Hebei Normal University, College of Life Sciences, No. 20 East Nanerhuan Road, Shijiazhuang, Hebei, 050024, China
2 - Shijiazhuang Academy of Agriculture and Forestry Sciences, Shijiazhuang Academy of Agriculture and Forestry Sciences, Shijiazhuang, Hebei, 050021, China
3 - Hebei Normal University, College of Life Sciences, No. 20 East Nanerhuan Road, Shijiazhuang, Hebei, 050024, China

cultivated plants
parental tracing.

Presentation Type: Oral Paper
Session: ETH1, Ethnobotany
Location: Virtual/Virtual
Date: Tuesday, July 28th, 2020
Time: 3:45 PM
Number: ETH1004
Abstract ID:604
Candidate for Awards:Economic Botany Section best student paper

Copyright © 2000-2020, Botanical Society of America. All rights reserved