Methods for sequence-directed molecular breeding
The present invention provides breeding methods and compositions to enhance the germplasm of a plant by the use of direct nucleic acid sequence information. The methods describe the identification and accumulation of preferred nucleic acid sequences in the germplasm of a breeding population of plants.
1. A method of plant breeding by multiplex sample sequencing and selection of a plurality of loci comprising:
providing two or more plant DNA samples;
amplifying at least two different loci from each genome of one of said DNA samples in a single multiplex PCR reaction to prepare a plurality of amplicons for each of said two or more plant DNA samples to prepare two or more multiplexed PCR samples;
tagging each of said two or more multiplexed PCR samples with a unique DNA tag to identify the sample origin to prepare two or more tagged multiplexed PCR samples;
combining at least two or more of said tagged multiplexed PCR samples to create a pool of tagged amplicons;
sequencing the said pool of tagged amplicons using high throughput (HT) sequencing to obtain pooled sequences;
binning the sequence information from said pooled sequences according to the sequence of said DNA tag to obtain sample specific bins of sequence information for each of said two or more plant DNA samples;
comparing the sequence of said at least two different loci between said two or more plant DNA samples; and
selecting one or more plants based upon differences between said at least two different loci in said two or more plant DNA samples.
2. The method as set forth in claim 1 , wherein the one or more selected plants are parents for a breeding population.
3. The method as set forth in claim 1 , wherein the one or more selected plants are progeny from a breeding population.
4. The method as set forth in claim 1 , wherein said at least two different loci comprises a polymorphism selected from the group consisting of a single nucleotide polymorphisms (SNPs), insertions or deletions in DNA sequence (Indels), simple sequence repeats of DNA sequence (SSRs), a restriction fragment length polymorphism, and a variation in copy number.
5. The method as set forth in claim 1 , wherein the plant is selected from the group consisting of a forage crop, oilseed crop, grain crop, fruit crop, ornamental plants, vegetable crop, fiber crop, spice crop, nut crop, turf crop, sugar crop, beverage crop, tuber crop, root crop, and forest crop.
6. The method as set forth in claim 1 , wherein said differences between said at least two different loci is indicative of an economically important trait in a plant and wherein said economically important trait is selected from the group consisting of herbicide tolerance, disease resistance, insect or pest resistance, altered fatty acid, protein or carbohydrate metabolism, increased grain yield, increased oil, enhanced nutritional content, increased growth rates, enhanced stress tolerance, preferred maturity, enhanced organoleptic properties, altered morphological characteristics, and sterility.
7. The method as set forth in claim 1 , wherein said at least two different loci comprises a polymorphism that is a transgene.
8. The method as set forth in claim 1 , wherein said at least two different loci comprises at least 96 loci.
9. The method as set forth in claim 1 , wherein said at least two different loci comprises at least 384 loci.
10. The method as set forth in claim 1 , wherein said two or more plant DNA samples comprises at least 96 plant samples.
11. The method as set forth in claim 1 , wherein said two or more plant DNA samples comprises at least 384 plant samples.
12. The method as set forth in claim 1 , wherein said amplifying and said tagging are performed simultaneously.
13. The method as set forth in claim 1 , wherein said amplifying and said tagging are performed sequentially.