Heterosis is a term used in genetics and selective breeding. It is also known as hybrid vigor, or outbreeding enhancement, describes the increased strength of different characteristics such as size, growth rate, fertility, yield, and tolerance to pests and environmental stress in hybrids over those of its parents.

Heterosis is widely exploited in applied plant breeding by plant breeders to the benefit of agriculture and society. Facing the challenge of population growth and cropland reduction, it is obvious that the only way to solve this problem is to improve the yield of cereal crops namely, rice, wheat and corn etc. For example, ~95% of U.S. maize average is planted to hybrids. As one of the most ancient grain crops, rice is a staple food for people due to it being high in carbohydrates, low in fat, and rich in proteins, vitamins and minerals. It has been used as a major food for over ten thousand years. The hybrid rice (Oryza sativa L.) breeding that was initiated in China in the 1970s led to a great improvement in rice productivity. It has been cultivated in 113 countries. It is estimated that half of the world¡¯s population subsists wholly or partially on rice. The Chinese Superhybrid Rice Genome Project, initiated by BGI in 2000, focused on the hybrid rice ¡°Liang You Pei Jiu¡± which was developed by the famous Chinese rice expert Longping Yuan, as the basic research object. The goal was to reveal the molecular mechanism of the hybridization advantages, thus providing the theoretical basis for improving output and selecting better strains of agriculture crops. The Heterosis related gene database (HRGD) is thus developed as an integrated information resource and analysis platform for genetic, genomic, and molecular studies of Heterosis.

HRGD hosts all rice HRG generated by BGI and curates all other published HRG sequences including maize, wheat. HRGD provides a series of tools and viewers for analyzing the expression patterns, functional categories, pathways of these genes comparatively. A searching system is developed for users to retrieve a combination of different data types by setting various search options. The BLAST, multiple sequence alignment tools and GO/KEGG functional analysis tools were integrated for online data analysis. HRGD aims to be a powerful information resource and an analysis workbench for scientists working on heterosis breeding.

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If you have any problem in using the HRGD database or you have new data to submit and update our database, please contact us. You could click on here to view the file format and detail instruction for your uplode file

 News

The current version of HRGD data was updated on 2007-8-13

The new EST data and Protein data will soon be uploaded

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