Arabidopsis enhanced drought tolerance1/HOMEODOMAIN GLABROUS11 confers drought tolerance in transgenic rice without yield penalty.

Linhui Yu,Shimei Wang,Qisheng Zhu,Shigui Li,Xi Chen,Yuping Wang,Zhen Wang,Chengbin Xiang

doi:10.1104/pp.113.217596

Abstract

Enhancing drought tolerance without yield decrease has been a great challenge in crop improvement. Here, we report the Arabidopsis (Arabidopsis thaliana) homodomain-leucine zipper transcription factor Enhanced Drought Tolerance/HOMEODOMAIN GLABROUS11 (EDT1/HDG11) was able to confer drought tolerance and increase grain yield in transgenic rice (Oryza sativa) plants. The improved drought tolerance was associated with a more extensive root system, reduced stomatal density, and higher water use efficiency. The transgenic rice plants also had higher levels of abscisic acid, proline, soluble sugar, and reactive oxygen species-scavenging enzyme activities during stress treatments. The increased grain yield of the transgenic rice was contributed by improved seed setting, larger panicle, and more tillers as well as increased photosynthetic capacity. Digital gene expression analysis indicated that AtEDT1/HDG11 had a significant influence on gene expression profile in rice, which was consistent with the observed phenotypes of transgenic rice plants. Our study shows that AtEDT1/HDG11 can improve both stress tolerance and grain yield in rice, demonstrating the efficacy of AtEDT1/HDG11 in crop improvement.

Highlights

Enhancing drought tolerance without yield decrease has been a great challenge in crop improvement
The transgenic lines exhibited a significantly higher survival ratio, ranging from 70.4% to 100% (Fig. 1B). These results demonstrate that AtEDT1/HDG11 can significantly improve drought tolerance of rice seedlings
The increased grain yield was largely contributed by larger panicle size and higher seed-setting rate (Table II), consistent with the greenhouse results. These results demonstrate that AtEDT1/HDG11 cannot only enhance drought tolerance in transgenic rice, and increase grain yield, making

Summary

Introduction

Enhancing drought tolerance without yield decrease has been a great challenge in crop improvement. We report the Arabidopsis (Arabidopsis thaliana) homodomain-leucine zipper transcription factor Enhanced Drought Tolerance/HOMEODOMAIN GLABROUS11 (EDT1/HDG11) was able to confer drought tolerance and increase grain yield in transgenic rice (Oryza sativa) plants. The improved drought tolerance was associated with a more extensive root system, reduced stomatal density, and higher water use efficiency. The everincreasing world population and frequent global climate change challenge the world agriculture to produce enough food to feed the world (HongBo et al, 2005) To meet this challenge, it is important to improve crop yields by breeding crops with enhanced stress tolerance. Two receptor-like kinases, ERECTA and O. sativa Stress-Induced Protein Kinase, were reported to affect stomatal density and drought tolerance in Arabidopsis and rice, respectively (Masle et al, 2005; Ouyang et al, 2010)

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Results

Conclusion