Crop Improvement and Seed Selection PDF

Review Class for the Licensure Examination for Agriculturists Crop Science Crop Improvement and Seed Selection Department of Plant Breeding and Genetics Julien R. Deroy 2022 T...

Review Class for the Licensure Examination for Agriculturists Crop Science Crop Improvement and Seed Selection Department of Plant Breeding and Genetics Julien R. Deroy 2022 Topics Concepts in crop improvement Basic Steps of Crop Improvement Germplasm Breeding and Selection Methods Varietal Registration Types of Cultivars Concept of Seed Certification Classes of Seeds Crop improvement refers to any form of genetic modification in plants to satisfy human needs Conventional approach Non-conventional approach Hybridization through Mutation Breeding controlled pollination Recombinant DNA Plant introduction technology (rDNA) Traditional phenotypic Marker-assisted selection selection Conventional approach Hybridization through Plant introduction controlled pollination Non-conventional approach Procedure of breeding with the usage of gamma radiation and adventitious buds method of regeneration in in vitro cultures Non-conventional approach Non-conventional approach  Setting breeding goals Assembly Release and cultivar maintenance of germplasm Basic Step of Crop Crop Improvement Improvement Creating Evaluation variability Selection  Setting breeding goals Assembly Crop Improvement Objectives: Release and maintenanc cultivar e of germplasm Crop Improvement Creating Evaluation variability Selection Current Issues Crop Improvement Objective Growing world population Increase crop yield production Low food and feed nutritional Bio-fortification in plants content Abiotic & biotic resistant plant Harsh environmental condition varieties Development of new unique Increasing demand of new horticultural plant varieties horticultural plant varieties Development of plant varieties Different specific production suitable for different production systems systems Development of plant varieties Different end-use requirements suitable for different end-user  Setting breeding goals Assembly and Germplasm Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability § refers to the sum total of all hereditary material in a single Selection (interbreeding) species § the lifeblood of plant breeding q Domesticated Plant qUndomesticated Plants - wild ü Commercial cultivars or weedy relatives of ü Breeding materials domesticated plants ü Landrace qOther related species and ü Plant introduction closer genera ü Genetic stocks  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability § refers to the differences between species, breeds, lines, or cultivars due to Selection the following sources of genetic variation: Recombination Mutation Gene Migration  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability § refers to the differences between species, breeds, lines, or cultivars due to Selection the following sources of genetic variation: 1. Recombination a process by which pieces of DNA are broken and recombined to produce new combinations of alleles. refers to the process by which progeny derive a combination of genes different from that of either parent.  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Conventional approach Non- conventional approach Controlled hybridization/ Gene transfer cross-pollination using the Somaclonal variation different mating design  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Conventional approach Controlled hybridization/ cross-pollination using the different mating design Recombination takes place during gamete formation  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Mating design refers to artificial crossing or mating scheme in plant breeding programs has two primary purposes: Ø To generate information for the breeder to understand the genetic control or behavior of the trait of interest Ø To generate a base population to initiate a breeding program.  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Types of Mating design 1. Hybrid crosses q Single cross (A x B = F1 AB) the process of q Three-way cross crossbreeding between (A x B = F1 x C = ABC) genetically dissimilar q Back cross parents to produce a (A x B = F1 x A = BC1) hybrid. q Double cross A x B = FAB C x D = FCD FAB x FCD = ABCD  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Types of Mating design 1 x 2 2. Biparental mating 3 x 4 Involves crossing a number of 5 x 6 parent lines paired at random 7 x 8 where each line is paired once 9 x 10 … x … 3. Polycross 1 2 3 4 5 6 7 8 9 intermating a group of parental 7 8 9 1 2 3 4 5 6 lines by natural crossing in an 4 5 6 7 8 9 1 2 3 isolated block.  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Types of Mating design 4. North Carolina Design I each male is mated to a different group of females 5. North Carolina Design II each male is mated to the same group of females  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Types of Mating design 6. North Carolina Design III a random sample of F2 plants is backcrossed to the two inbred lines from which the F2 was descended.  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Recombination Non-conventional approach 1. Gene transfer involves recombinant DNA (rDNA) technology, a state-of- the-art gene transfer that generates genetic variability for plant breeding  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Recombination Non-conventional approach 2. Soma-clonal variation refers to the heritable variation among In vitro culture of plants Recombination is induced by prolonging the callus stage and use of growth hormones  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Recombination Non-conventional approach 2. Soma-clonal variation Is characterized by the following changes: 1. karyotypic changes 2. Cryptic chromosomal rearrangements  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Recombination Non-conventional approach 2. Soma-clonal variation 3. somatic crossing over 4. sister chromatid exchange  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Recombination Non-conventional approach 2. Soma-clonal variation 5. transposable elements 6. gene amplification  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability 2. Mutation Selection § a change in the DNA sequence of an organism results from errors in DNA replication during cell division, exposure to mutagens, or a viral infection. § Types of mutagens § Radiation § Chemical § Extreme environment § Cell regeneration § Hybridization  Setting breeding goals Assembly and Genetic Variability Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability 2. Migration of Genes Selection § the introduction of genetic material (by interbreeding) from one population of a species to another, thereby changing the composition of the gene pool of the receiving population.  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection refers to the process of discriminating genetic variability and advancing selected individuals to the next generation or breeding cycle in order to develop potential new cultivars most fundamental of techniques used by plant breeders throughout the ages involves the used standard selection or breeding methods suitable for the species and the breeding objective(s)  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 1. Mass Selection oldest method of breeding self- pollinated plant species (applicable also in cross pollinated crops) aims to improve the population by increasing the gene frequencies of desirable genes discriminates individual based on plant phenotype  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 1. Mass Selection  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 2. Pure line selection The theory of the pure line was developed in 1903 by the Danish botanist Johannsen entails repeated cycles of selfing following the initial selection from a mixture of homozygous lines. produces line cultivars with a narrow genetic base and tend to be uniform in traits of interest  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 3. Pedigree selection is a widely used method of breeding self- pollinated species (even cross-pollinated species) employs hybridization to generate variability breeder keeps records of the ancestry of the cultivar.  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 4. Bulk population strategy of crop improvement in which natural selection effect is solicited more directly in the early generations of the procedure by delaying stringent artificial selection until later generations.  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 5. Single seed descent was born out of a need to speed up the breeding program by rapidly inbreeding a population prior to beginning individual plant selection and evaluation, while reducing a loss of genotypes during the segregating generations. advance the maximum number of F2 plants through the F5 generation  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 5. Single seed descent Year 1. The crossing is used to create the base population. Cross-selected parents to generate an adequate number of F1 for the production of a large F2 population. Year 2. About 50–100 F1 plants are grown in a greenhouse ground bench or pots. They may also be grown in the field. Harvest identical F1 crosses and bulk. Year 3. About, 2000–3000 F2 plants are grown. At maturity, a single seed per plant is harvested and bulked for planting F3. Subsequently, F2 is spaced enough to allow each plant to produce only a few seeds. Year 4–6. Single pods per plant are harvested to plant the F4. The F5 is space-planted in the field, harvesting seed from only superior plants to grow progeny rows in the F6 generation. Year 7. Superior rows are harvested to grow preliminary yield trails in the F7. Year 8 and later. Yield trials are conducted in the F8 to F10 generations. As a new cultivar, the most superior line is increased in the F11 and F12  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Selection Methods 6. Recurrent selection is a cyclical improvement technique which aims to improve the performance of a population with respect to one or more traits of interest, such that the new population is superior to the original population in mean performance and in the performance of the best individuals within it  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 7. Family selection methods Half-sib family selection Recombination of selected families or plants within families Creation of a Full-sib family selection to create a new base family population for the structure. Selfed (S1 or S2) families next cycle of selection. selection Evaluation of families and selection of superior ones by progeny testing.  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 7. Family selection methods Half-sib family selection widely used for breeding perennial forage grasses and legumes. A polycross mating system is used to generate the half-sib families from selected vegetatively maintained clones  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Selection Methods 7. Family selection methods Full-sib family selection are generated from biparental crosses using parents from the base population. The families are evaluated in a replicated trial to identify and select superior full-sib families, which are then recombined to initiate the next cycle.  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Selection Methods 7. Family selection methods q Selfed (S1 or S2) families selection The key features are generations S1 or S2 families, evaluating them in replicated multi- environment trials, followed by recombination of remnant seed from selected families  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 8. Family selection based on test cross The key feature of this approach to selection is that it is designed to improve both the population per se as well as its combining ability Half-sib selection with progeny test Half-sib selection with test cross Half-sib reciprocal recurrent selection  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Methods Selection 8. Family selection based on test cross The key feature of this approach to selection is that it is designed to improve both the population per se as well as its combining ability Half-sib selection with progeny test Half-sib selection with test cross Half-sib reciprocal recurrent selection  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Selection Methods 8. Family selection based on test cross Half-sib selection with progeny test  Setting breeding goals Assembly and Selection Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection Selection Methods 8. Family selection based on test cross Half-sib selection with test cross  Setting breeding goals Assembly and Evaluation Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability refers to the process of assessing the Selection performance of newly developed lines through a series of appropriate trials and tests. Stages of Evaluation 1. Observational test is done by the original plant breeder and it is conducted in separate groups of experimental lines using an incomplete block design or triple lattice with 2-3 replications in one location.  Setting breeding goals Assembly and Evaluation Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Stages of Evaluation Selection 2. Preliminary yield test is done at the breeder’s level and conducted using check variety in an incomplete block design with 2-3 replication in at least 2 locations 3. General yield test – is performed by the breed using randomized complete block design with 3 replication in at least 3 locations. 4. Advanced yield test – is conducted under the supervision of the National Cooperative Testing Level using randomized complete block design with 4 replication in 6-10 locations.  Setting breeding goals Assembly and Varietal Registration Process Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability is governed by the Selection National Seed Industry Council (NSIC) through the Republic Act 7308, otherwise known as the Seed Industry Development Act was enforced in 1992. https://www.da.gov.ph /wp- content/uploads/2021/ 05/ao19_s2021.pdf  Setting breeding goals Assembly and Varietal Registration Process Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection  Setting breeding goals Assembly and Varietal Registration Process Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection  Setting breeding goals Assembly and Varietal Registration Process Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection  Setting breeding goals Assembly and Varietal Registration Process Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection  Setting breeding goals Assembly and Types of Cultivar Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection a. Pure line (inbred) is developed through self-pollination and has a narrow genetic base b. Open-pollinated variety is developed through natural cross-pollination and it is genetically heterogeneous and heterozygous in nature. c. Hybrid is produced by crossing inbred lines that have been evaluated for their ability to produce hybrids with superior vigor over and above those of the parents used in the cross.  Setting breeding goals Assembly and Types of Cultivar Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection d. Clonal cultivar is developed through hybridization and propagated vegetative. e. Apomictic cultivars produces seed that are genetically identical to the mother plant. f. Multiline cultivars are developed through self pollination and consist of a mixture of specially developed genotypes called isolines (or near isogenic lines) because they differ only in a single gene (or a defined set of genes)  Setting breeding goals Assembly and Types of Cultivar Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection g. Synthetic cultivar defines as an advanced generation of cross-fertilized seed mixture of parents that may be strains, clones, or hybrids. h. Composite cultivar refers to the mixtures of less similar genotypes  Setting breeding goals Assembly Seed Certification and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection It is a legal mechanism established to ensure that pedigree seed produced by a plant breeder reaches the public in its highest quality, original genetic identity, and highest genetic purity. This is governed by the Bureau of Plant Industry (BPI) -National Seed Quality Control Services (NSQCS), as the seed certifying agency of the DA. BPI shall enforce rules and regulations on seed certification through the regional field offices of the DA.  Setting breeding goals Assembly Seed Certification and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability 1. Application for Seed Grower Accreditation Selection  Setting breeding goals Assembly Seed Certification and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability 1. Application for Seed Grower Accreditation Selection  Setting breeding goals Assembly Seed Certification and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 2. Field inspection – inspection of the field by authorized seed inspectors at least three times per cropping season as per standards established such as isolation requirements, presence of off-types, admixtures and weeds, and incidences of seed-borne diseases and pests, among others. 3. Seed sampling – drawing of a quantity of seed from a seed lot in accordance with the International Rules of Seed Testing or as prescribed by NSIC.  Setting breeding goals Assembly Seed Certification and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 4. Seed Testing – accurate and prompt analysis of seed sample to determine the planting value of seed based on the methodologies prescribed by the ISTA. Sample seeds are tested based on the following quality attributes such as: Germination Purity varietal purity moisture content seed health Vigor mechanical injury  Setting breeding goals Assembly Seed Certification and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection The following crops require seed testing: § Agricultural Seed and Vegetable Seed Tree § Shrub Seed Flower § Spice, Herb, and Medicinal Species Once the seeds meets or exceed the minimum standards set by the BPI, the seed is declared officially certified and receives the official tag indicating the results of seed analysis (percentage germination, inert matter, weed seed, etc.).  Setting breeding goals Assembly Seed Certification and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 5. Tagging. After all field and laboratory standards are met, seed lots are then issued certification tags. Different seed classes are issued different colors: white-breeder seeds; red-foundation seeds; green-registered seeds; and blue-certified seeds. 6. Inspection of seed warehouses, processing plants, and seed producers/dealers‘ distribution centers and production areas. 7. Pre and post-control test-investigation of growing cultivars and the occurrence of certain seed-borne diseases grown on field plots. It needs familiarity of well-trained staff with the characteristics of the variety.  Setting breeding goals Assembly Classes of Seeds and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 1. Breeder seed the highest purity produced, developed, controlled, and provided directly by breeders or their institutions for further multiplication. Tag: White 2. Foundation seed the progeny of the breeder seed produced by trained officers of an agricultural station in conformity with regulated national standards and handled to maintain genetic purity and identity of the variety. Tag: Red  Setting breeding goals Assembly Classes of Seeds and Release maintenan cultivar ce of germplas Crop m Improvemen t Creating Evaluation variability Selection 3. Registered seed the progeny of the foundation seed grown by selected farmers, handled to maintain genetic purity and identity, and has undergone field and seed inspections to ensure conformity with standards. Tag: Green 4. Certified seed the progeny of foundation, registered, or certified seeds, handled to maintain sufficient varietal identity and purity, grown by selected farmers under prescribed conditions of culture and isolation, and subjected to field and seed inspections prior to approval by the certifying agency. Harvest from this class is used for commercial planting. Tag: Blue References Acquaah, G. (2012). Principles of plant genetics and breeding. 2nd ed. Hoboken, NJ: Wiley. http://www.knowledgebank.irri.org/training/fact-sheets/postharvest-management/rice-quality-fact- sheet-category/item/seed-certification-fact-sheet https://nsic.buplant.da.gov.ph/irr.php https://byjus.com/biology/recombinant-dna-technology/ https://www.biotecharticles.com/Biotech-Research-Article/Marker-Assisted-Selection-and-its- Applications-in-Vegetable-Crops-3909.html Zalewska M. , Miler N. , Tymoszuk A. , Drzewiecka B. , Winiecki J. 2010. RESULTS OF MUTATION BREEDING ACTIVITY ON Chrysanthemum × grandiflorum (Ramat.) Kitam. IN POLAND, EJPAU 13(4), #27.