One is the extraction and recombination of inbreds combined with selection. This is because mass selection increases the occurrence of the desirable genes in a population. Recurrent selection sprague and eberhart, 1977 is used for traits that are polygenically inherited. This has led researchers to investigate other options, such as farmerparticipatory plant breeding, for delivering the. Mass selection is a method of crop improvement for both the selfpollinated and the cross pollinated plants. The breeding methods that have proved successful with selfpollinated species are. A massselection method for the acclimatization and. Within family selection uses the best individual from each family for breeding. Between family selection uses the whole family for selection.
Results are given from an experiment to monitor progress. Selection is then imposed on rows or plots of the progeny. At the end of bulking period, individual plant selection. Plant breeders must have access to genetic variation in crop species. Ken russell, department of agronomy and horticulture, university of nebraska. Mass selection in animal breeding is when certain animals are chosen for certain desirable traits to pass on. 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. B pure line selection c clonal selection d mass selection. Reinventing quantitative genetics for plant breeding. It is a purposeful manipulation of plants to create desired plant types that are better suited for cultivation, give better yield and are disease resistant. Plant breeding and genetics encyclopedia of life support. In normal mass selection progeny test is not performed. Plant breeding definition, methods, steps and videos. Mass selection is one of the oldest methods of crop improvement.
Dec 19, 2017 the only disadvantage of mass selection is that it is difficult to distinguish hereditary variation from environmental variation. This method is mainly based upon the easily observable characters are taken into consideration. Mass selection is used in both self pollinated and cross pollinated species. A computer is used to document and randomize the plantings. In case of cross pollinated species the mass selected varieties are heterozygous and heterogeneous. In this method only human selection or artificial selection is used. Introduction to plant breeding plant breeding is the use of natural and artificial selection to produce heritable variations and novel combinations of alleles in plants and to identify plants with novel and useful properties.
Withinfamily selection when the heritability of a character is high, an individuals phenotype is an excellent predictor of its breeding value, and mass selection is more ef. Once those animals are obtained, they are bred to control what traits the offspring. In this method, individual plants are selected on the basis of. There are two defects of mass selection as given below.
Plant breeders must be equipped with the tools to respond quickly to new demands by developing accelerated breeding. Single plant selection, mass selection, pedigree method, and bulk population method are the common breeding methods followed for bitter gourd breeding. Feb 06, 2017 an overview of pedigree method being employed in the plant breeding. Plant breeding, application of genetic principles to produce plants that are more useful to humans. Population stratified into a number of different blocks i. Method of plant breeding in self pollinated plants pedigree methods mass selection and pure line selection cannot be applied to segregating population. When a large number of plants of similar phenotype are selected and their seeds are mixed together to constitute a new variety is called mass. The expected result is a set of genetically homogeneous lines. Mass selection is often described as the oldest method of breeding.
Maize is a staple food crop in many developing countries. Mass selection in this method, plants are selected based on their desirable morphological characters phenotype. Pure line selection a pure line is a collection of plants obtained as a result of repeated selfpollination from a single homozygous individual. Lec 22 population improvement programmes, recurrent selection, synthetics and composites 9 lec 23 hybrids 140143 lec 24 clonal selection 144148 lec 25 hybridization 149152 lec 26 mutation breeding 153157 lec 27 procedure for mutatuion breeding 158162 lec 28 application of mutatuion breeding 163166 lec 29 1 ploidy breeding 167180 lec 30 2 ploidy breeding. Method of plant breeding in self pollinated plants pedigree. The method is generally used for handling segregation generation may be grouped into three categories. As this plant is monoecious, production of f 1 hybrids is simple and economical. The selected plants should be of similar phenotype as the seeds are mixed together. In this method a group of progenies offrprings are used as an aid to increase accuracy in the selection ofa breeding. Mass selection is practiced both in self and cross pollinated crop plants.
Dec 19, 2017 selection methods are of two types mass selection and pure line selection. However, it is more common in cross pollinated species than in self pollinated species. This process of selection is continued till the plants show uniformity in the desired characters and they constitute a new variety. Apr 15, 2020 the marriage between quantitative genetics and plant breeding, albeit nonexclusive, has reaped benefits for both during the last 100 years. Plant breeding can be accomplished through many different techniques ranging from simply selecting plants with desirable. The following points highlight the four main of plant breeding methods. Recurrent selection an overview sciencedirect topics. Elements and underpinnings of plant breeding introduction to section 1 1. The relationship between genetics and postmendelian plant breeding is exemplified by a number of now routine breeding protocols.
The goals of plant breeding are to produce crop varieties that. This mixture of seeds is a mass, and, therefore, it is known as mass selection. Johannsens pure line theory and its concepts and significance origin of variation in pure lines. Mass selection definition of mass selection by merriamwebster. A number of highperforming lines are crossed back to the recurrent parent to initiate. Selection methods are of two types mass selection and pure line selection. Mass selection in mass selection, seeds are collected from usually a few dozen to a few hundred desirable appearing individuals in a population, and the. Objectives of plant breeding pdf general knowledge mcq. Sc ag seed science and technology department of genetics and plant breeding shiats allahabad up. Mass selection in mass selection, seeds are collected from usually a few dozen to a few hundred desirable appearing individuals in a population, and the next generation is sown from the stock of mixed seed. Pure line selection is a type of plant breeding in which development of a variety which is highly uniform is done with the involvement of a single plant. Plant breeding plant breeding breeding selfpollinated species. The characteristics such as the height of the plant, size and colour of the grain etc. Mass selection definition is selection as breeding stock of those members of a population exhibiting desirable qualities or elimination of those showing undesirable qualities.
Through cultivation of plants and domestication of animals, humans were able to. Progeny testing is a offspring resulting from selected parents family selection. This is the commonest approach taken to improving landraces. Jul 02, 2015 contents introduction characters of cross pollinated crops methods of breeding in cross pollinated crops mass selection progeny selection or eartorow method modified eartorow method recurrent selection hybrid varieties synthetic varieties breeding methods common for both self and cross pollinated crops. Mass selection is important for crosspollinating crops but has only limited application in selfpollinating crops. This has led researchers to investigate other options, such as farmerparticipatory plant breeding.
Genetic improvement of vegetable crops sciencedirect. Estimates of genetic variances and heritability in many. Plant breeding dates to the very beginnings of agriculture, though scientific plant breeding began only in the early 20th century. Pureline selection consists of four major steps, viz 1 selection of a heterogeneous population from which purelines have to be isolated, 2 isolation of purelines by individual plant selection. Difference between mass selection and pure line selection. In order to accommodate the high environmental variance with individual plant values, gardner 1961 proposed the method of stratified mass selection. Plants in the c22 cycle were 50 cm taller had twice the leaf area index, reached anthesis 7 days later and had a 30% higher harvest index than c0 table 1 clarification needed. Natural selection is allowed to operate only in the modified form of pedigree breeding known as mass pedigree method. Plant breeding breeding selfpollinated species britannica. Aims and objectives of plant breeding plant breeding is an art and science, which tells us ways and means to change the genetic architecture of plants so as to attain a particular objective. Thus it is a cyclic selection that is used to improve the frequency of desirable alleles for a character in a breeding population. However, if seven major maize producing countries are excluded from this group, data indicate that only 34% of the maize area is planted with improved seed despite considerable effort invested in maize breeding. Important characters of each selected plant and progeny are recorded. This method is also called mass selection, or selection on own performance.
Plant breeders must be equipped with the tools to respond quickly to new demands by developing accelerated breeding techniques. Selection methods in plant breeding based on mode of. Breeding selfpollinated species types of cultivars at the beginning of each project, the breeder should. Heterosis is exploited in bitter gourd breeding as well. Key difference mass selection vs pure line selection plant breeding procedures deal with the. Method of plant breeding in self pollinated plants. Sep 29, 2017 mass selection vs pure line selection.
Plant breeding is a method of altering the genetic pattern of plants to increase their value and utility for human welfare. Pdf selection methods in plant breeding ammar elakhdar. Multiple choice quiz on plant breeding biology multiple. Stratified mass selection for ear size over 22 cycles clarification needed has drastically altered plant phenotype in the maize population zacatecas 58. Principles of plant breeding icar ecourse pdf book agrimoon. Thus it is a cyclic selection that is used to improve the frequency of desirable alleles for a character in a breeding. Mass selection procedure for evolving a variety by mass selection modification of mass selection merits, demerits and achievements 9. Mass selection refers to a methods of crop improvement in which individual plants are selected. Review of genetics from the perspective of a plant breeder 4. Especially in mass selection, which is still used in the breeding of various allogamous crops, the acceleration of breeding cycles and the possibility of pollen control with gs will enhance the genetic gain per unit time yabe et al.
Environmental factors and technology in growing plants dennis. Mass selection and the basic plant breeding algorithm 6. Learn more about the uses and methods of plant breeding. The present study may encourage application of gs to mass selection breeding. This type of selection method of plant breeding can be carried out multiple times as mass selected variety may contain considerable genetic variation.
Although there is a tendency to equate the beginnings of plant breeding with the rediscovery of mendels laws, major plant breeding discoveries were made prior to 1900. Pure line selection and mass selection breeding methods. Polygenic inheritance occurs when many genes, each with a small effect, control the expression of a trait. The progeny of single plant selections are kept separate, not bulked together. Participatory plant breeding with maize in mexico and. Recurrent selection is a variation of backcross breeding, where selection for performance is practiced within consecutive segregating progeny generations after the population has undergone selection for the major trait being transferred green et al. The only disadvantage of mass selection is that it is difficult to distinguish hereditary variation from environmental variation. Learn about the comparison between pure line selection and mass selection. Recurrent selection is a method which involves reselection generation after generation with interbreeding of selects to provide for genetic recombination. It is a method which can handle segregating generations, in which f 2 and subsequent generations are harvested in bulk to grow the next generation. The marriage between quantitative genetics and plant breeding, albeit nonexclusive, has reaped benefits for both during the last 100 years. Mass selection in this method, plants are selected based on their desirable morphological. The procedure is more effective as careful progeny test.
Plant breeding is the art and science of improving the heredity of plants for the benefit of. At the end of bulking period, individual plant selection and evaluation is carried out in the similar fashion as in the pedigree method. Mass selection the most basic way is to rank the animals according to their phenotype and select the best ones for breeding. The plants are selected for their desirability of characters that may not be similar phenotype. Mass selection is a type of plant breeding in which a heterozygous variety with genetic variations is developed by mixing several pure lines. Mass selection is an example of selection from a biologically variable population.