Molecular breeding

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

Cereal Genomics II

Abstract: During the last decades, major advances have been made in the field of cereal genomics. For instance, high-density genetic maps, physical maps, QTL maps and even draft genome sequence have become available for several cereal species. This has been facilitated by the development of next generation sequencing (NGS) technologies, so that, it is now possible to sequence genomes of hundreds or thousands of accessions of an individual cereal crop. Significant amounts of data generated using these latest NGS technologies created a demand for computational tools to analyse this massive data. These developments related to technology and the tools, along with their applications not only to plant and genome biology but also to breeding have been documented in this volume. The volume, entitled “Cereal Genomics II”, therefore supplements the earlier edited volume “Cereal Genomics” published in 2004. The new volume has updated chapters, from the leading authorities in their fields, on molecular markers, next generation sequencing platform and their use for QTL analysis, domestication studies, functional genomics and molecular breeding. In addition, there are also chapters on computational genomics, whole genome sequencing and comparative genomics of cereals. The book should prove useful to students, teachers and young research workers as a ready reference to the latest information on cereal genomics.

Genetic Architecture and Genomic Prediction of Cooking Time in Common Bean (Phaseolus vulgaris L.).

Abstract: Cooking time of the common bean is an important trait for consumer preference, with implications for nutrition, health, and environment. For efficient germplasm improvement, breeders need more information on the genetics to identify fast cooking sources with good agronomic properties and molecular breeding tools. In this study, we investigated a broad genetic variation among tropical germplasm from both Andean and Mesoamerican genepools. Four populations were evaluated for cooking time (CKT), water absorption capacity (WAC), and seed weight (SdW): a bi-parental RIL population (DxG), an eight-parental Mesoamerican MAGIC population, an Andean (VEF), and a Mesoamerican (MIP) breeding line panel. A total of 922 lines were evaluated in this study. Significant genetic variation was found in all populations with high heritabilities, ranging from 0.64 to 0.89 for CKT. CKT was related to the color of the seed coat, with the white colored seeds being the ones that cooked the fastest. Marker trait associations were investigated by QTL analysis and GWAS, resulting in the identification of 10 QTL. In populations with Andean germplasm, an inverse correlation of CKT and WAC, and also a QTL on Pv03 that inversely controls CKT and WAC (CKT3.2/WAC3.1) were observed. WAC7.1 was found in both Mesoamerican populations. QTL only explained a small part of the variance, and phenotypic distributions support a more quantitative mode of inheritance. For this reason, we evaluated how genomic prediction (GP) models can capture the genetic variation. GP accuracies for CKT varied, ranging from good results for the MAGIC population (0.55) to lower accuracies in the MIP panel (0.22). The phenotypic characterization of parental material will allow for the cooking time trait to be implemented in the active germplasm improvement programs. Molecular breeding tools can be developed to employ marker-assisted selection or genomic selection, which looks to be a promising tool in some populations to increase the efficiency of breeding activities.

An Update on Genetic Modification of Chickpea for Increased Yield and Stress Tolerance

Abstract: Chickpea is a highly nutritious grain legume crop, widely appreciated as a health food, especially in the Indian subcontinent. The major constraints on chickpea production are biotic (Helicoverpa, bruchid, aphid, ascochyta) and abiotic (drought, heat, salt, cold) stresses, which reduce the yield by up to 90%. Various strategies like conventional breeding, molecular breeding, and modern plant breeding have been used to overcome these problems. Conventionally, breeding programs aim at development of varieties that combine maximum number of traits through inter-specific hybridization, wide hybridization, and hybridization involving more than two parents. Breeding is difficult in this crop because of its self-pollinating nature and limited genetic variation. Recent advances in in vitro culture and gene technologies offer unique opportunities to realize the full potential of chickpea production. However, as of date, no transgenic chickpea variety has been approved for cultivation in the world. In this review, we provide an update on the development of genetically modified chickpea plants, including those resistant to Helicoverpa armigera, Callosobruchus maculatus, Aphis craccivora, as well as to drought and salt stress. The genes utilized for development of resistance against pod borer, bruchid, aphid, drought, and salt tolerance, namely, Bt, alpha amylase inhibitor, ASAL, P5CSF129A, and P5CS, respectively, are discussed.