Open Access

ARTICLE

Estimation of Growth and Photosynthetic Performance of Two C₄ Species (Pennisetum spicatum (L.) Körn. and Zea mays L.) under a Low Temperature Treatment

by Abdulkhaliq Alshoaibi^*

Department of Biology, Faculty of Science, Taibah University, Almadinah Almunawwarah, 41311, Saudi Arabia

* Corresponding Author: Abdulkhaliq Alshoaibi. Email:

(This article belongs to the Special Issue: Plant Physiology for Crop Production and Sustainable Agriculture)

Phyton-International Journal of Experimental Botany 2022, 91(1), 45-55. https://doi.org/10.32604/phyton.2022.016434

Received 05 March 2021; Accepted 12 April 2021; Issue published 16 August 2021

Abstract

Pearl millet (Pennisetum spicatum (L.) Körn.) and maize (Zea mays L.) are C₄ grass species grown for feeding humans and animals in Almadinah Almunawwarah, which is in the western part of Saudi Arabia. During the winter, the mean temperature, which drops to 14°C, represents a major problem for the growth of these species in this region. Therefore, the objectives of this research were to investigate the growth response and the photosynthetic performance of P. spicatum and Z. mays under a low temperature stress. The treatments involved daytime and nighttime temperatures of 14/12°C (low temperature) and 24/22°C (optimum temperature). The results indicated that low temperature significantly reduced all growth and physiological parameters, including seed germination, leaf expansion, leaf area, shoot length and root length of the two species compared to those of the control. Additionally, the low temperature significantly decreased the light-saturated assimilation rate (A_sat), quantum yield (ϕ), saturated rate of carbon dioxide uptake (A_max) and efficiency of carboxylation on both species compared to those of the control. Moreover, the values of Fv/Fm and the chlorophyll contents of both species were significantly reduced by low temperature compared to those of the control. It can be concluded that both species had little tolerance to low temperatures.

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Keywords

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