Molecular breeding

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

Molecular Breeding of Selçuklu-97 Durum Wheat Cultivar for Some Genes Affecting Pasta Quality

Abstract: The most efficient way of producing and supplying proper raw material desired by the pasta industry is the development of high quality durum wheat varieties. Therefore, quality of Turkish durum wheat varieties should be improved using modern breeding methods without adversely affecting their yields. In this study, important genes (y-gliadin 45 and LMW-2 glutenin) affecting the quality of pasta products were transferred to a Turkish durum wheat variety, Selcuklu-97, in a backcross breeding method in combination with marker assisted selection (MAS). A Canadian durum wheat cultivar with high quality, Kyle, was used as the donor parent. Each of F1 and backcross (BC) plants was backcrossed four times to the recurrent parent and in all of the generations, backcrossed plants carrying the targeted QTLs were selected by the MAS. The MAS method was employed in combination with embryo culture and rapid plant growth in a controlled greenhouse conditions. In identifying and transferring processes of the gene regions, molecular DNA markers (SSR, STS and GAG) were employed with A-PAGE and SDS-PAGE methods. A-PAGE was used for selection of y-gliadin 45, SDS-PAGE for selection of LMW-2 glutenins, and four SSR primers (Xgwm550, Xgwm608, Stm553actc, Stm542acag), one STS primer and one PCR primer (GAG5-6) linked to Gli-B1 and Glu-B3 loci for selection of y-gliadin 45 and LMW-2 glutenins either all together or alternatively. As a result, the study was completed in three years instead of six years required in a classical backcross breeding study, meaning about 50 % time saving, and obtained a high quality candidate variety.

Molecular Mapping and Breeding of Physiological Traits

Abstract: Submit Manuscript | http://medcraveonline.com in molecular biology experimentation, and systems analyses in finding solutions to the challenging goals of plant breeding and agricultural biotechnology for crop improvement [1]. In addition, the amount of genetic variability particularly additive genetic variability available and the effectiveness with which the selection is performed for the trait of interest decides the advance of any breeding program. Selection based on phenotypic basis becomes confined especially when the traits are of complex nature. Here, molecular markers may prove to be beneficial as they provide several advantages over traditional phenotypic markers [1]. Hence, selection based on molecular marker approach will be more precise and accurate way of selection. This method will screen the markers linked to the gene(s) or quantitative trait loci (QTLs). Drought is the most devastating abiotic stress affecting crop productivity. The primary step to understand the genetic control of tolerance is the physiological dissection of complex traits that as a result could improve competence of molecular breeding strategies [2]. High temperature related to drought promotes evapotranspiration and affects photosynthetic kinetics intensifying the effects of drought and resulting into reduced crop yields. Unfortunately, in response to climate change, the occurrence of drought in many food-producing regions has been predicted to be increased considerably [3,4]. Hence, it is focused to ensure sustainable and long-term benefits through genetic improvement for water stress tolerance [5]. There is acute need for having corresponding information of plant physiological response and integrative modelling to embark upon the puzzling effects connected with environment and gene interaction [6]. Physiological progress in this connection increases the probability of crosses resulting in additive gene action for stress adaptation, a benefit over empirical breeding for yield per se offering thorough characterization of the germplasm than for yield alone [7]. Further, mapping and cloning of genes concerned in various physiological traits is somewhat a complex progression. However, sequencing technology has provided affluence of genomic (total DNA) and expressed sequence information in locating, interpreting, and assigning biological function [8]. Plant breeding institutes have adopted the capacity for marker development and marker-assisted selection (MAS) recognizing the enormous potential of DNA markers. Though non-molecular biologists may not understand the utility of DNA markers in plant breeding in view of the rapid progresses made in marker technology, statistical methodology for identifying quantitative trait loci (QTLs) and the terminology used by molecular biologists. This review provides an introduction to criteria for using physiological traits in breeding programmes; molecular markers that includes DNA markers and the concept of polymorphism; QTL detection for physiological traits focusing upon mapping QTLs relevant to photosynthetic potential, absorption and assimilation of nutrients, flowering, drought tolerance and water use efficiency. Besides these, a brief idea regarding heat tolerantrelated morpho-physiological traits followed by techniques for identification of putative molecular markers associated with root traits have been also incorporated. This compact and comprehensive review can be of assistance to related researchers. Criteria for using Physiological Traits in Breeding Programmes

Identification of Candidate Genes for Drought Stress Tolerance

Abstract: Drought is one of the major abiotic stresses that threaten the growth and yield of plants. Drought tolerance is one mechanism by which plants can resist drought stress. In plants, the ability to tolerate drought is programmed at the genetic level. Drought response in the model plant Arabidopsis thaliana was a subject of extensive dissection especially at the molecular level. With the recent biotechnological advances in sequencing techniques, the genome of many important crops such as rice, maize, and barley has been sequenced. Indeed, genome sequencing of these crops paved the way for transcription profiling under different environmental stresses including drought. Transcription profiling using microarrays is the number one choice for the identification of genes for drought tolerance. Identification of candidate genes for drought tolerance is a basic step towards the improvement of drought-tolerant crops either through molecular breeding or a transgenic approach. In this chapter, an effort has been made for the identification and function of candidate genes for drought tolerance in the model plant A. thaliana as well as some other major crops.

Approaches for associating molecular polymorphisms with phenotypic traits based on linkage disequilibrium in natural populations of Lolium perenne

Abstract: Skot, L., Humphreys, J., Armstead, I. P., Humphreys, M. O., Gallagher, J. A., Thomas, I. D. (2005). Approaches for associating molecular polymorphisms with phenotypic traits based on linkage disequilibrium in natural populations of Lolium perenne. Page 157 in: Humphreys, M. O. (Ed.). Molecular Breeding for the Genetic Improvement of Forage Crops and Turf. Wageningen Academic Publishers, ISBN: 978-90-76998-73-2. Proceedings of the 4th International Symposium on the Molecular Breeding of Forage and Turf. XXth International Grassland Congress, July 2005, Aberystwyth, Wales.