Effect of High-Temperature Stress on Plant Physiological Traits and Mycorrhizal Symbiosis in Maize Plants.

Vangimalla R. Reddy,Sonal Mathur,Anjana Jajoo,Richa Agnihotri,Mahaveer P. Sharma

doi:10.3390/jof7100867

Abstract

Increasing high temperature (HT) has a deleterious effect on plant growth. Earlier works reported the protective role of arbuscular mycorrhizal fungi (AMF) under stress conditions, particularly influencing the physiological parameters. However, the protective role of AMF under high-temperature stress examining physiological parameters with characteristic phospholipid fatty acids (PLFA) of soil microbial communities including AMF has not been studied. This work aims to study how high-temperature stress affects photosynthetic and below-ground traits in maize plants with and without AMF. Photosynthetic parameters like quantum yield of photosystem (PS) II, PSI, electron transport, and fractions of open reaction centers decreased in HT exposed plants, but recovered in AMF + HT plants. AMF + HT plants had significantly higher AM-signature 16:1ω5cis neutral lipid fatty acid (NLFA), spore density in soil, and root colonization with lower lipid peroxidation than non-mycorrhizal HT plants. As a result, enriched plants had more active living biomass, which improved photosynthetic efficiency when exposed to heat. This study provides an understanding of how AM-mediated plants can tolerate high temperatures while maintaining the stability of their photosynthetic apparatus. This is the first study to combine above- and below-ground traits, which could lead to a new understanding of plant and rhizosphere stress.

Highlights

Maize (Zea mays L.) is one of the important and widely grown commercial crops of the world
Higher chlorophyll content in arbuscular mycorrhizal fungi (AMF) enriched plants compared to high temperature exposed plants could be associated with an increased photosynthesis rate or an increase in the N and Mg content of plants accompanied with an increased carbohydrate/sugar accumulation
The damaging effect of high-temperature stress on PSI and photosystem II (PSII) was restrained by arbuscular mycorrhizal fungi enrichment

Summary

Introduction

Maize (Zea mays L.) is one of the important and widely grown commercial crops of the world. Higher temperatures (HT) (35 ◦ C and above) affect the vegetative and reproductive growth of maize, from germination to grain filling [2]. High-temperature stress-induced responses in plants include modifications in the photosynthetic machinery, organizational changes in cellular structures to maintain membrane functioning, and stomatal closure to limit transpirational water loss [3]. A slight increase in temperature can have a negative impact on growing crops, grain filling, and yield [4]. Jagdish et al [5] reported that heat stress such as short term HT, heat waves, or long term high temperature, have a detrimental effect on plant growth and yield [5]

Objectives

Methods

Results

Discussion

Conclusion