Department of agronomy and plant genetics, university of minnesota. The agricultural benefits associated with these adjuvant solutions are the major factors contributing to the growth of this market, globally. The parent which receives a desirable character is known as recipient parent. A cross between f1 hybrid and one of its parents is known as a backcross. The principal feature of the backcross method is the unequal genetic contribution of the two.
Abqtl approach displayed that the genetic potential of exotic germplasm cannot be predicted. Today, the backcross procedure is most often used to move a transgene from a good tissue culture variety that was used in transformation to an elite experimental line. The objective of backcross method is to improve one or two specific defects. View backcross method from plant bree pbg 201 at university of agriculture. If the trait of interest is produced by a dominant gene, this process involves four rounds of backcrossing within seven seasons.
The current status of the backcross method of plant breeding plant breeders have expressed the belief that it will not work with cross pollinated crops. This dossier explains all standard techniques used in modern plant breeding and why they have been. Backcrossing may be deliberately employed in animals to transfer a desirable trait in an animal of inferior genetic background to an animal of preferable genetic background. Pdf fundamentals of genetics and plant breeding md. Qtl quantitative trait loci, genetic analysis and characterization of crops with various dna markers and isozymes. If the trait of interest is produced by a dominant gene, this process involves four rounds of. Pdf selection methods in plant breeding ammar elakhdar. Part iii plant breeding terms american hosta society. Lec 17 hybridization aims, objectives and types of hybridization 8088. Plant breeding and genomics community of practice presents. List reasons why backcross breeding is necessary in devel.
Back cross method and various modified methods backcross method in backcross method of breeding, the hybrid and the progenies in subsequent generations are repeatedly backcrossed to one of the parents. The bickcross breeding method has been useful in develop ing early. Backcrossing is an old breeding method that is now. Pedigree refers to record of the ancestry of an individual selected plant.
Essential of plant breeding pdf free download agriculture study. This decisionmaking is important to develop a framework for organic plant breeding and facilitate investment by breeding companies. A cross between a hybrid f 1 or a segregating generation and one of its parents is known as backcross. Lec 16 methods of breeding introduction and acclimatization 7179 lec 17 hybridization aims, objectives and types of hybridization 8088 lec 18 back cross method and various modified methods 8999 lec 19 1 incompatibility and male sterility and their utilization in crop improvement 100111. The national association of plant breeders in partnership. Pedigree breeding is a method of genetic improvement of selfpollinated species. With each successive backcross, there is an increase in the percentage of c57b6j dna that constitutes the genome of the offspring. However, the current plant breeding methods are entirely based on scientific principles of plant sciences. Backcross breeding accelerated by marker assisted background genome selection. Dec 04, 2014 test cross and backcross are two types of popular crosses in plant breeding. Principles of plant breeding icar e course free pdf book.
Method of plant breeding in self pollinated plants back. Molecular breeding market by process, marker, application and region 2023 the molecular breeding market is estimated at usd 1. Much smaller population is needed in this method than in pedigree method. The variety which receives gene is recipient parent and variety which is the source of gene is called as donor parent. It is proposed by harian and pope in 1922, as a method breeding for small grains and is employed in improvement of both hybrid. Backcross refers to crossing of f1 with either of its parents. In view of these and other objections to the method, it. Backcrossed hybrids are sometimes described with acronym bc, for example, an f1 hybrid crossed with one of its parents can be termed a bc1 hybrid, and a further cross of the bc1 hybrid to the same par. Outlines of breeding methods, plant introduction, pureline selection, mass and progeny selections, clonal selection, pedigree method, bulk breeding method, backcross method, recurrent selection, heterosis breeding, synthetic and composite, population improvement approaches. May, 2019 plant breeding is selection made possible by the existence of variability. Backcrossing is a crossing of a hybrid with one of its parents or an individual genetically similar to its parent, in order to achieve offspring with a genetic identity which is closer to that of the parent.
Same form whether self or cross pollinated species in the b. This seems to violate mendels postulate of independent assortment of genes and can make it difficult to pick out a single trait from one parent without also bringing. Mar, 2018 method of plant breeding in self pollinated plants back cross method. Plant breeding strategies used by the international maize and wheat improvement center cimmyt encapulate the way in which modern plant breeding should be pursued. There is the only method for interspecific gene transfers, and for the transfer of cytoplasm. In this method, the parent used for backcrossing has a large number of desirable attributes but lacks a few characteristics.
Dnabased marker resources permit selection for recurrent. This is done by crossing a donor parent to an elite line, and crossing offspring with the desired gene s back to the elite parent. Method of plant breeding in self pollinated plants pedigree. Plant breeding definition, methods, steps and videos. In terms of breeding system, selfpollination is an extreme form of inbreeding, rapidly restores homozygosity. The method of breeding does not get modified whether the character is dominant or recessive gene controlled. An established breeding program with clear aims and reasonable resources will produce a new variety regularly, every couple of years or so. With all of the advances in molecular biology, it may seem surprising to find out that traditional plant breeding methods are still needed in the development of plant varieties.
Backcross breeding essentially a method for improving an established variety that is deficient in only one or a few characteristics the backcross generations converge on a single genotype only breeding method in which the results are both predictable and repeatable. Ppt backcross breeding powerpoint presentation free to. The backcross breeding ntethod was applied to a cooperative tomato improvement proiect. With all of the advances in molecular biology, it may seem surprising to find out that traditional plant breeding methods are still needed in the development of. With all the advances in molecular biology, it may seem surprising to know that traditional plant breeding methods are. Backcross method is applicable in all three groups of crop plants, viz.
Plant breeding techniques for vegetativelypropagated plants 7. You must get to the floral parts before the plant pollinates itself or is pollinated by another plant. Plant breeding david luckett and gerald halloran what is. When a large number of plants of similar phenotype are selected and their seeds. Lec 19 1 incompatibility and male sterility and their utilization in crop 100111. Backcrossing is the plant breeding method most widely used to incorporate one or a few genes into an elite or adapted variety. Application of biotechnology in plant breeding programs. In backcross method of breeding, the hybrid and the progenies in subsequent. In short, plant breeding is the manipulation of a biological system that requires many generations to achieve results which is a dynamic, exciting and challenging profession operating under continually changing conditions. Most of our crops can be classified as cross pollinated or self pollinated cross pollinated means that an insect or wind normally carries pollen from one plant to another in order to fertilize it self pollinated means that the plant will pollinate and fertilize itself both types require that you. Lec 16 methods of breeding introduction and acclimatization 7179. Molecular marker technology, marker assisted selection in plant breeding. Plant breeding strategies used by the international maize and wheat improvement center cimmyt encapulate the way in which modern plant breeding.
It typically takes more than ten years for a variety to proceed from the initial breeding stages through to commercial release. The method is generally used for handling segregation generation may be grouped into three categories. The backcross breeding technique has been extensively used to improve a specific. It is used in horticulture, animal breeding and in production of gene knockout organisms. Backcross breeding enables breeders to transfer a desired trait such as a transgene from one variety donor parent, dp into the favored genetic background of another recurrent parent, rp. F 2 and subsequent generations are much larger than those of the backcross method. Introduction to backcross breeding advanced backcross. Pureline cultivars pureline cultivarsare developed for species that are highly selfpollinated. Advanced backcross ab qtl analysis is a method which combines qtl analysis with variety development. Principles of plant breeding icar ecourse pdf book agrimoon. Raising backcross fls and crossing resistant plants with recurrent parent is. Plant breeding breeding selfpollinated species britannica. Gonzalezcamacho, sergio perezelizalde,2 yoseph 1 beyene, susanne dreisigacker, 1ravi singh, xuecai 8 zhang, manje gowda,1.
Merit of backcross method the genotype of new variety is nearly identical with of the recurrent parent except for the genes transferred. Pdf improving grain yield and yield components via backcross. The f2 generation is sown at normal commercial planting rates in a large plot. Within certain limits the backcross offers the plant breeder such an exact method. Plant introduction definition taking a genotype or a group of genotypes in to a new place or environment where they. These cultivars are homogeneous and homozygous in genetic structure, a con. Plant breeding methods and use of classical plant breeding. Jun 30, 2019 method of plant breeding in self pollinated plants pedigree methods mass selection and pure line selection cannot be applied to segregating population. The genotype of new variety is nearly identical with that of the recurrent parent, except for the gene transfer. The breeding methods that have proved successful with selfpollinated species are. In many ways it is, to the plant breeder, the equivalent of line breeding to the stock breeder, with the added advantage that many plants are nob harmed even by. Patel, associate research scientist, main vegetable research station, aau, anand. Backcross method for dominant and recessive gene transfer.
A breeding method used to move one or only a few desirable genes from an agronomically poor crop line to an elite line. Backcross method involves two types of parents, viz. Backcrossing has been used by plant breeders for decades to transfer specific character into elite lines. Nov 14, 2019 backcross breeding is an effective method to transfer one or a few genes controlling a specific trait from one line into a secondusually elitebreeding line. Backcross helps to recover important characters of the parent population within hybrid populations. The parent with the desired trait, called the donor parent, provides the desired trait and may not perform as well as an elite variety in other areas. Transfer of pollen from an anther to a stigma within the same flower or to a stigma of another flower on the same plant. Genetic linkage is a phenomenon in which genes tend to be inherited together. Rust resistant plants are backcrossed with recurrent parent a. The new variety is subjected to extensive testing and yield trial before releasing as new variety. Main objective of this method is to obtain a new variety with desirable genes combination. Pedigree method in this method individual plants are selected in f 2 and the subsequent generations and their progenies are tested.
When the f1 is crossed with homozygous recessive parent. Pdf on dec 10, 2017, jakir hossain published backcross breeding find, read and cite all the research you need on researchgate. Intro to the crop basic botanymating system important traits. The use of the backcross in crop improvement jstor. Plant breeding can be defined as an art, a science, and technology of improving the genetic make up of plants in relation to their economic use for the man kind. Pdf selection in backcross programmes researchgate. The conventional method of backeross breeding allard, 1960 or its mod ification has been. Back cross method and various modified methods backcross method in backcross method of breeding, the hybrid and the. Test cross happens between a dominant phenotype with the recessive phenotype to determine the genotype of the dominant phenotype. Method of plant breeding in self pollinated plants. The relative efficiencies of the use of backcross and f2 families for telocentric. Thus plant breeding toda y is largely a science with litt le involvement of art.
As a result, the genotype of the backcross progeny becomes increasingly similar to that of the recurrent parent. The bulkpopulation method of breeding differs from the pedigree method primarily in the handling of generations following hybridization. Backcross breeding is an effective method to transfer one or a few genes controlling a specific trait from one line into a secondusually elite. This often means opening the flower long before it is ready. Bc populations, and backcross breeding plant breeding and. Lec 18 back cross method and various modified methods 8999. Intercrossing among individual plants in an hybrid population is also. Recipient parent is used repeatedly hence also named as recurrent parent. Difference between test cross and backcross compare the. The theory and application of the backcross technique in cotton. Individual plant selection is continued till the progenies become homozygou s and they show no segregation.
An adapted organic plant breeding approach must include the development of improved varieties for organic farming without violating its ethical and ecological principles. The dossier will provide decision makers and practitioners of organic farming with the requisite information and criteria for an objective and transparent assessment of plant breeding methods. Plant breeding plant breeding breeding selfpollinated species. In other words, formation of a seed by union of the male and the female gametes from the same plant also refered as autogamy. Methods of breeding introduction and acclimatization. Most of our crops can be classified as cross pollinated or self pollinated cross pollinated means that an insect or wind normally carries pollen from one plant to another in order to fertilize it self pollinated means that the plant will. Apr 04, 2021 many plant breeders test for five years at five representative locations before releasing a new variety for commercial production. F 2 and subsequent generations are much larger than those of the backcross method 8. Combine many traits from two parents in the longterm, pedigree selection recurrent selection oh 88119 used as a parent in commercial hybrids, early with concentrated fruit set. The use of the backcross in crop improvement the university of. Backcross method 18 back cross method and various modified.
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