Molecular breeding

About: Molecular breeding is a research topic. Over the lifetime, 2120 publications have been published within this topic receiving 56908 citations.

Phenomics: A Challenge for Crop Improvement in Genomic Era

Abstract: The last two decades have observed tremendous progress in the genomics for plant breeding research, especially the availability of a large number of high-throughput cost-effective molecular markers and genotyping platforms, advances in sequencing technologies leading the reduction in sequencing costs and making available genome sequences of major crop genomes, etc. But the advance in phenomics is lagging far behind our present day capacity to generate high-throughput molecular genotyping data, thus creating phenotypic bottleneck”. The accurate and precise phenotypic data is an essential component in the discovery of genes/QTLs of important agronomic traits using modern genomic approaches; otherwise it leads to false positives and false negatives. Therefore, it necessitates the development of high-throughput phenotyping facilities. Although, several phenotyping facilities have been developed around the world that can scan and record precise and accurate data for thousands of plants quickly by making use of non-invasive imaging, spectroscopy, image analysis, robotics and high-performance computing facilities, but more efforts and funds are required to be allocated in this field to achieve fruitful results from genomics/molecular breeding approaches like QTL interval mapping, association mapping, genome-wide association studies (GWAS), QTL cloning, QTL validation, marker-assisted selection (MAS), marker-assisted recurrent selection (MARS), TILLING (Targeting Induced Local Lesions in Genomes) and genomic selection (GS) or genome-wide selection (GWS).

Application of Next Generation Sequencing and Genotyping Technologies to Develop Large‐Scale Genomic Resources in SAT Legume Crops

Abstract: Molecular markers and genetic maps are the pre‐requisites for trait mapping and genomics‐assisted crop improvement. However, very limited genomic resources were available until recently for the legume crops important in the semi‐arid tropics (SAT). As a part of several initiatives, species‐specific genomic resources are now being developed in most of these legume crops. For instance, using simple sequence repeat (SSR)‐enriched libraries and bacterial artificial chromosome (BAC)‐end sequence mining approaches, nearly 1,500‐ 3,000 novel SSR markers have been developed for chickpea, pigeonpea and groundnut. In addition, next generation sequencing technologies like Roche 454/FLX and Illumina/Solexa, in addition to Sanger sequencing, are being used to sequence the transcriptomes of reference or parental genotypes of mapping populations of chickpea and pigeonpea to access the gene space and develop functional markers. Based on Sanger and 454/FLX transcript reads, transcriptome assemblies have been developed for chickpea (103,215 tentative unique sequences, TUSs) and pigeonpea (127,754 TUSs) that are being characterized using genome sequence data of Medicago and soybean. In parallel, RNA of four chickpea and twelve pigeonpea genotypes, that represent parents of different mapping populations, have been sequenced by using Illumina/Solexa sequencing approach that has resulted ca. 120 million reads for chickpea and 20 million reads for pigeonpea. Alignment of these Illumina/Solexa reads of these genotypes with transcriptome assembly of the respective species has provided a large number (tens of thousands) of SNPs. Selected set of SNPs are being used to develop large‐scale SNP genotyping platform in chickpea and pigeonpea. By using the existing resource of SSR, SNP and DArT markers, high‐density genetic maps are being developed in these species for trait mapping and molecular breeding. It is anticipated that molecular breeding practice may be routine and part of breeding activities in the SAT legumes in coming future

Maize authentication detection and molecular breeding SNP chip - maizeSNP3072 and detection method thereof

Abstract: Disclosed is a use of 3072 SNP sites originating from maize during maize variety authentication detection and molecular breeding process. In the use of the present invention, the physical positions of the 3072 SNP sites are determined based on the whole-genome sequence alignment of the maize variety B73; the version number of the whole-genome sequence of the maize variety B73 is B73 RefGen V1; and the 3072 SNP sites are MC0001-MC3072. An experiment confirms that the authenticity of the to-be-detected maize variety can be discriminated via the comparison between the 3072 SNP sites genotype of a to-be-detected maize sample genome DNA and the 3072 SNP sites genotype of a control maize sample genome DNA. The combined use of the 3072 SNP sites of the present invention significantly improves detection accuracy and shortens detection time, thus greatly improving the maize variety detection technology level of China; in addition, the 3072 SNP sites can also be used for maize molecular breeding and providing important technical support therefor.

The analysis of functional genes in maize molecular breeding

Abstract: Molecular breeding is capable of improving important agricultural crop traits by controlling functional genes, aiming to attain high yield, stability and quality. During this process, the quantity and maneuverability of functional genes are important in determining breeding efficiency. In our research, 186 functional genes relating to maize agronomic traits, which are available for marker-assisted selection or genetic transformation strategies, were collected from the literature and projected onto an integration map. The traits corresponding to these functional genes included disease resistance, stress tolerance, tassel traits, ear traits, kernel-related traits, leaf traits and plant-type characteristics. The integration map demonstrated that these functional genes were unevenly distributed on maize chromosomes. The greatest and fewest numbers of functional genes were found on chromosomes 1 and 8, respectively. Moreover, 36, 25, 27, 23, 14, 15, 11, 6, 9 and 20 genes were found on chromosomes 1 to 10, respectively. Most of disease-resistant genes were found on chromosome 10, while the genes of kernel-related and leaf-related traits were found on chromosomes 4 and 2, respectively. Out of the 186 functional genes, 95 have been characterized using genetic mapping, 19 using map-based cloning, 53 using transposon-tagging cloning strategies and 19 using other methods. Thus, the number of functional genes identified in maize is still limited and further research on functional genes is required.