Navigation Links
Statistical model predicts performance of hybrid rice

RIVERSIDE, Calif. Genomic prediction, a new field of quantitative genetics, is a statistical approach to predicting the value of an economically important trait in a plant, such as yield or disease resistance. The method works if the trait is heritable, as many traits tend to be, and can be performed early in the life cycle of the plant, helping reduce costs.

Now a research team led by plant geneticists at the University of California, Riverside and Huazhong Agricultural University, China, has used the method to predict the performance of hybrid rice (for example, the yield, growth-rate and disease resistance). The new technology could potentially revolutionize hybrid breeding in agriculture.

The study, published online this week in the Proceedings of the National Academy of Sciences, is a pilot research project on rice. The technology can be easily extended, however, to other crops such as maize.

"Rice and maize are two main crops that depend on hybrid breeding," said Shizhong Xu, a professor of genetics in the UC Riverside Department of Botany and Plant Sciences, who co-led the research project. "If we can identify many high-performance hybrids in these crops and use these hybrids, we can substantially increase grain production to achieve global food security."

Genomic prediction uses genome-wide markers to predict future individuals or species. These markers are genes or DNA sequences with known locations on a chromosome. Genomic prediction differs from traditional predictions in that it skips the marker-detection step. The method simply uses all markers of the entire genome to predict a trait.

"Classical marker-assisted selection only uses markers that have large effects on the trait," Xu explained. "It ignores all markers with small effects. But many economically important traits are controlled by a large number of genes with small effects. Because the genomic prediction model captures all these small-effect genes, predictability is vastly improved."

Without genomic prediction, breeders must grow all possible crosses in the field to select the best cross (hybrid). For example, for 1000 inbred parents, the total number of crosses would be 499500.

"It is impossible to grow these many crosses in the field," Xu said. "However, with the genomic prediction technology, we can grow only, say, 500 crosses, then predict all the 499500 potential crosses, and select the best crosses based on the predicted values of these hybrids."

Xu noted that genomic prediction is particularly useful for predicting hybrids because hybrid DNA sequences are determined by their inbred parents.

"More cost-saving can be achieved because we do not need to measure the DNA sequences of the hybrids," he said. "Knowing the genotypes of the parents makes it possible to immediately know the genotype of the hybrid. Indeed, there is no need to measure the genotype of the hybrid. It is fully predicted by the model."

When the researchers incorporated "dominance" and "epistasis" into their prediction model, they found that predictability was improved. In genetics, dominance describes the joint action of two different alleles (copies) of a gene. For example, if one copy of a gene has a value of 1 and the other copy has a value of 2, the joint effect of the two alleles may be 4, indicating that the two alleles are not additive. In this case, dominance has occurred. Epistasis refers to any type of gene-gene interaction.

"By incorporating dominance and epistasis, we took into account all available information for prediction," Xu said. "It led to a more accurate prediction of a trait value."

Genomic prediction can be used to predict heritable human diseases. For example, many cancers are heritable and genome prediction can be performed to predict disease risk for a person.

Xu was joined in the research by Qifa Zhang and his student Dan Zhu at Huazhong Agricultural University, China.

Next the research team, led by Xu and Zhang, will design a field experiment to perform hybrid prediction in rice.


Contact: Iqbal Pittalwala
University of California - Riverside

Related biology news :

1. Statistical test increases power of genetic studies of complex disease
2. New statistical models could lead to better predictions of ocean patterns
3. New research helps place modern temperatures into a more complete statistical framework
4. Synteract to Host Joint Statistical Meeting Roundtable in San Diego
5. A new application allows online statistical analysis of gene-expression data
6. Clinical trial tests COXEN model to predict best treatment for bladder cancer
7. Reduction of tau protein improves symptoms in model of severe childhood epilepsy
8. UTSA researcher awarded NSF grant to create computer models for food insecurity project
9. A new way to model cancer
10. C. difficile vaccine proves safe, 100 percent effective in animal models
11. Classic Lewis Carroll character inspires new ecological model
Post Your Comments:
Related Image:
Statistical model predicts performance of hybrid rice
(Date:11/17/2015)... , Nov. 17, 2015 Pressure BioSciences, ... in the development and sale of broadly enabling, pressure ... life sciences industry, today announced it has received gross ... $5 million Private Placement (the "Offering"), increasing the total ...  One or more additional closings are expected in the ...
(Date:11/12/2015)... 2015   Growing need for low-cost, easy ... been paving the way for use of biochemical ... analytes in clinical, agricultural, environmental, food and defense ... in medical applications, however, their adoption is increasing ... continuous emphasis on improving product quality and growing ...
(Date:11/9/2015)... DUBLIN , Nov. 09, 2015 /PRNewswire/ ... announced the addition of the "Global ... to their offering. --> ... "Global Law Enforcement Biometrics Market 2015-2019" ... Research and Markets ( ) ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... 2015 /CNW/ - iCo Therapeutics ("iCo" or "the Company") ... for the quarter ended September 30, 2015. Amounts, ... and presented under International Financial Reporting Standards ("IFRS"). ... said Andrew Rae , President & CEO ... not only value enriching for this clinical program, ...
(Date:11/24/2015)... Tampa, Florida (PRWEB) , ... November 24, 2015 ... ... its biggest event of the year and one of the premier annual events ... USA, and ran from 8–11 November 2015, where ISPE hosted the largest number ...
(Date:11/24/2015)... Global, Inc., a worldwide provider of clinical research services headquartered in ... company has set a new quarterly earnings record in Q3 of ... for Q3 of 2014 to Q3 of 2015.   ... with the establishment of an Asia-Pacific office ... Kingdom and Mexico , with the ...
(Date:11/24/2015)... ... November 24, 2015 , ... This fall, global software solutions leader SAP and ... to develop and pitch their BIG ideas to improve health and wellness in their ... votes to win the title of SAP's Teen Innovator, an all-expenses paid trip to ...
Breaking Biology Technology: