Effects of elevated atmospheric CO₂ concentration on morphology of leaf blades in Chinese yam

Abstract

The effects of elevated carbon dioxide concentration on the morphology of leaf blades in two Chinese yam lines under different temperature conditions were determined. Plants were grown under two [CO 2 ] levels, ambient (about 400 µmol mol −1 ) and elevated (ambient + 200 µmol mol −1 ) in the daytime, and two mean air temperature regimes, approximately ambient temperature (22.2°C) and high temperature (25.6°C). The palisade layer was thicker under elevated [CO 2 ] than under ambient [CO 2 ] in both temperature regimes, and the whole yam leaf blade was thicker under elevated [CO 2 ] than under ambient [CO 2 ] in the approximately ambient temperature regime. The numbers of chloroplasts per palisade cell and spongy cell as well as per unit profile area of palisade cell, number of starch grains per chloroplast, profile area of the starch grain, and starch-to-chloroplast area ratio in both palisade and spongy cells were higher under elevated [CO 2 ] than under ambient [CO 2 ] in both temperature regimes. Furthermore, the stomatal density on the abaxial side of the leaf blade in Chinese yam was greater under elevated [CO 2 ] than under ambient [CO 2 ] under both temperature regimes, and stomatal-pore length was higher under elevated [CO 2 ] than under ambient [CO 2 ] in the approximately ambient temperature regime. These results indicate that elevated [CO 2 ] positively affects the photosynthetic apparatus. The results of this study provide information for understanding the response characteristics of the leaf blade under elevated [CO 2 ] and a possible explanation for the positive photosynthetic responses of Chinese yam to elevated [CO 2 ] in our previous study. List of Abbreviations:[CO 2 ]: carbon dioxide concentration ARTICLE HISTORY

Interplay between Plant Functional Traits and Soil Carbon Sequestration under Ambient and Elevated CO2 Levels

“…eCO 2 generally leads to larger leaf area, size, thickness, increased number of veins, and decreased stomatal density in crop plants. Increased plant height, altered root and shoot branching characteristics, increased ratio of internode length to node number, and increased stem diameter under eCO 2 have also been reported [53,57,58]. Root traits such as root length, root diameter, and other root morphological developments may be enhanced under eCO 2 , which implies increased potential for CS [53,59].…”

Environmental adaptability of the genus Carex-A case study of Carex heterostachya and Carex breviculmis in northwest China

“…For instance, the relatively stable leaf structure traits are capable of indicating the maximization of carbon harvest (Correa et al 2018;Taylor et al 2012). The leaf thickness will increase signi cantly at the extremely high CO 2 concentration in the environment (Teng et al 2006;Thinh et al 2018). The leaf physiological traits-Photosynthesis has been found as the physiological basis for plant growth and development (Evans 2013).…”

Effect of environmental gradients on leaf morphological traits in the Fandoghlo forest region (NW Iran)

“…Leaf morphology is incredibly variable both among and within species (Hovenden & Vander Schoor 2006). Leaf morphological traits of most woody plants change with the local environmental conditions as a response to change in abiotic factors like soil moisture (Kolodziejek & Michlewska 2015), air temperature (Holland & Richardson 2009), solar radiation (Bussotti et al 1998), and atmospheric CO 2 concentration (Thinh et al 2018). Understanding the adaptive modifications of leaf traits to changes in environmental conditions, e.g., along elevation gradients, is vital (Akinlabi et al 2014).…”