Multiple Abiotic Stresses Applied Simultaneously Elicit Distinct Responses in Two Contrasting Rice Cultivars.

Fatemeh Habibpourmehraban,Karthik Shantharam Kamath,Farhad Masoomi-Aladizgeh,Brian J. Atwell,Jemma X. Wu,Ardeshir Amirkhani,Yunqi Wu,Paul A. Haynes,Sara Hamzelou

doi:10.3390/ijms23031739

Abstract

Rice crops are often subject to multiple abiotic stresses simultaneously in both natural and cultivated environments, resulting in yield reductions beyond those expected from single stress. We report physiological changes after a 4 day exposure to combined drought, salt and extreme temperature treatments, following a 2 day salinity pre-treatment in two rice genotypes—Nipponbare (a paddy rice) and IAC1131 (an upland landrace). Stomata closed after two days of combined stresses, causing intercellular CO2 concentrations and assimilation rates to diminish rapidly. Abscisic acid (ABA) levels increased at least five-fold but did not differ significantly between the genotypes. Tandem Mass Tag isotopic labelling quantitative proteomics revealed 6215 reproducibly identified proteins in mature leaves across the two genotypes and three time points (0, 2 and 4 days of stress). Of these, 987 were differentially expressed due to stress (cf. control plants), including 41 proteins that changed significantly in abundance in all stressed plants. Heat shock proteins, late embryogenesis abundant proteins and photosynthesis-related proteins were consistently responsive to stress in both Nipponbare and IAC1131. Remarkably, even after 2 days of stress there were almost six times fewer proteins differentially expressed in IAC1131 than Nipponbare. This contrast in the translational response to multiple stresses is consistent with the known tolerance of IAC1131 to dryland conditions.

Highlights

Rice is a critical staple food crop feeding nearly half of the people in the world, and with world population expected to increase to more than 9.5 billion by 2050, producing new varieties of rice with high yield and stress tolerance is essential for sustainable rice productivity [1]
We propose that the pattern of translational responses to combined abiotic stresses could differ qualitatively from the responses to individual stresses reported across disparate experimental protocols
We tested the hypothesis that multiple stresses elicit an immediate translational response, which is more than the simple sum of responses to individual stresses [6]

Summary

Introduction

Rice is a critical staple food crop feeding nearly half of the people in the world, and with world population expected to increase to more than 9.5 billion by 2050, producing new varieties of rice with high yield and stress tolerance is essential for sustainable rice productivity [1]. The sensitivity of rice plants to soil and atmospheric abiotic stress factors—including salt, drought and temperature stresses—is a major threat to rice yields worldwide [2]. Natural vegetation and even highly managed crops often encounter multiple stresses simultaneously, commonly as combinations of drought, salinity and non-optimal temperatures [3,4]. We propose that the pattern of translational responses to combined abiotic stresses could differ qualitatively from the responses to individual stresses reported across disparate experimental protocols. We tested the hypothesis that multiple stresses elicit an immediate translational response, which is more than the simple sum of responses to individual stresses [6]

Methods

Results

Discussion

Conclusion