Developmental changes in spatial distribution of in vivo fluorescence and epidermal UV absorbance over Quercus petraea leaves.

Ann Bot

Laboratoire Ecologie Systématique et Evolution, CNRS, UMR 8079 (CNRS, UPS, AgroParisTech), Université Paris-Sud, Bât. 362, F-91405 Orsay, France.

Published: September 2009

Background And Aims: Epidermal phenolic compounds (mainly flavonoids) constitute a vital screen that protects the leaf from damage by natural ultraviolet (UV) radiation. The effectiveness of epidermal UV-screening depends on leaf anatomy, the content of UV-screening compounds and their spatial uniformity over the leaf area. To investigate in vivo the spatial pattern of the epidermal UV-screen during leaf development, a fluorescence imaging method was developed to map the epidermal UV-absorbance at a microscopic scale. This study was done on oak (Quercus petraea) leaves that were used as a model of woody dicotyledonous leaves.

Methods: The leaf development of 2-year-old trees, grown outdoors, was monitored, at a macroscopic scale, by in vivo measurements of chlorophyll content per unit area and epidermal UV-absorbance using two optical leaf-clip meters. The distribution of pigments within leaves was assessed in vivo spectroscopically. The microscopic images of UV-induced fluorescence and UV-absorbance acquired in vivo during leaf development were interpreted from spectral characteristics of leaves.

Key Results: At a macroscopic scale, epidermal UV-absorbance was high on the upper leaf side during leaf development, while it increased on the lower leaf side during leaf expansion and reached the adaxial value at maturity. At a microscopic scale, in immature leaves, for both leaf sides, the spatial distribution of epidermal UV-absorbance was heterogeneous, with a pattern depending on the flavonoid content of vacuoles in developing epidermal cells. At maturity, epidermal UV-absorbance was uniform.

Conclusions: The spatial pattern of epidermal UV-screen over the area of oak leaves is related to leaf anatomy during development. In vivo spectroscopy and fluorescence imaging of the leaf surface showed the distribution of pigments within the leaf and hence can provide a tool to monitor optically the leaf development in nature.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2729627PMC
http://dx.doi.org/10.1093/aob/mcp144DOI Listing

Publication Analysis

Top Keywords

leaf development
20
epidermal uv-absorbance
20
leaf
15
epidermal
11
spatial distribution
8
quercus petraea
8
petraea leaves
8
leaf anatomy
8
spatial pattern
8
pattern epidermal
8

Similar Publications

Higher PEPC activity and vein density contribute to improve cotton leaf water use efficiency under water stress.

Plant Biol (Stuttg)

January 2025

Key Laboratory of Oasis Eco-agriculture, Xinjiang Production and Construction Corps, Shihezi University, Shihezi, China.

Plants with the C photosynthetic pathway can withstand water stress better than plants with C metabolism. However, it is unclear whether C photosynthesis can be preliminarily activated in droughted cotton leaves, and if this contributes to increase in water use efficiency (WUE). An upland cotton (Gossypium hirsutum L.

View Article and Find Full Text PDF

Intein-mediated split Cas9 for genome editing in plants.

Front Genome Ed

January 2025

Key Laboratory of Herbage and Endemic Crop Biology, Ministry of Education, Inner Mongolia University, Hohhot, Inner Mongolia, China.

Virus-induced genome editing (VIGE) technologies have been developed to address the limitations to plant genome editing, which heavily relies on genetic transformation and regeneration. However, the application of VIGE in plants is hampered by the challenge posed by the size of the commonly used gene editing nucleases, Cas9 and Cas12a. To overcome this challenge, we employed intein-mediated protein splicing to divide the transcript into two segments (Split-v1) and three segments (Split-v3).

View Article and Find Full Text PDF

Study on Antibacterial Activities of and Leaf Extracts Against Some Human Pathogens.

ScientificWorldJournal

January 2025

Department of Biology, College of Science, Bahir Dar University, P. O. Box 79, Bahir Dar, Ethiopia.

The present study was aimed to verify the medicinal value of and traditionally used to treat human and animal ailments in Ethiopia. Fresh leaves of these species were collected, dried under shade, and ground into fine powder. The extraction was carried out by the maceration method using methanol as a solvent.

View Article and Find Full Text PDF

Leaf vein, an essential part of leaf architecture, plays significant roles in shaping the proper leaf size. To date, the molecular mechanisms governing leaf development including leaf venation patterning remains poorly understood in birch. Here, we performed the genome-wide identification of homeodomain-like (HD-like) superfamily genes using phylogenetic analysis and revealed the functional role of a potential HD-like gene in leaf growth and development using transgenic technology and transcriptomic sequencing.

View Article and Find Full Text PDF

Objective: Phyllodes tumor (PT) is a variant of fibroepithelial proliferations of the breast, histologically demonstrating a leaf-like pattern. The WHO has categorized PTs as benign, borderline, or malignant based on their histological characteristics. The objective of this paper is to assess the clinicopathological factors with malignancy in PT of the breast.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!