Research Highlights

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  • Genetics

Published online: 21 May 2008 | doi:10.1038/nchina.2008.115

Genetics: Productivity booster

Jane Qiu

Introduction

© (2008) istockphoto.com/Thammarat Kaosombat

The productivity of rice is determined by plant height, flowering time and crop yield — traits known to be regulated by genes in several positions called quantitative trait loci on chromosome 7. Qifa Zhang and co-workers at the Huazhong Agricultural University in Wuhan¹ have isolated one such gene named Ghd7, which has a crucial role in simultaneously regulating all these traits in rice.

The Ghd7 protein contains a so-called CCT domain, which is shared by many molecules that regulate flowering time, circadian rhythm and light signalling across plant species. The researchers found that light stimulates Ghd7 expression in rice plants and that the level of Ghd7 protein correlated to the length of the day.

Interestingly, Ghd7 had no effects on genes associated with the circadian clock. By contrast, increased expression of Ghd7 under long-day conditions suppressed Ehd1 and Hd3a, which have been known to induce flowering, and gave rise to taller plants with bigger clusters of flowers.

By screening a variety of natural rice strains, Zhang and co-workers identified several Ghd7 mutations in strains grown in the Heilongjiang province of northeastern China, which resulted in proteins with reduced functions. The researchers hold the opinion that this mutation may have allowed rice to be cultivated in temperate and cool regions.

The authors of this work are from:
National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan, China.

Reference

1. Xue, W. et al. Natural variation in Ghd7 is an important regulator of heading date and yield potential in rice. Nature Genet. doi: 10.1038/ng.143 (2008). | Article |