Plant Breeding: Genetics and Breeding Methods MCQs 2026

Transgressive segregation refers to progeny that

1. A show no genetic variation at all ✓
2. B exceed the range of both parents for a trait ✓
3. C are always sterile hybrids ✓
4. D contain only cytoplasmic genes ✓

Pure line varieties are generally most suitable for

1. A obligate cross-pollinated crops only ✓
2. B self-pollinated crops ✓
3. C seedless crops only ✓
4. D perennial forest trees only ✓

The unit of heredity that controls a specific character is called a

1. A gene ✓
2. B chromatid ✓
3. C gamete ✓
4. D zygote ✓

A cross between two individuals differing in one pair of contrasting characters is called a

1. A dihybrid cross ✓
2. B monohybrid cross ✓
3. C test cross ✓
4. D backcross ✓

The phenotypic ratio of a typical Mendelian monohybrid F2 generation is

1. A 1:2:1 ✓
2. B 9:3:3:1 ✓
3. C 3:1 ✓
4. D 1:1 ✓

A test cross is made by crossing an individual with a

1. A homozygous dominant parent ✓
2. B heterozygous dominant parent only ✓
3. C polyploid parent only ✓
4. D homozygous recessive parent ✓

In self-pollinated crops, the breeding method most directly producing a uniform homozygous variety is

1. A pure line selection ✓
2. B mass selection without progeny testing ✓
3. C synthetic variety development ✓
4. D topcross testing only ✓

Selection is least effective for traits with

1. A high heritability and large variation ✓
2. B simple qualitative inheritance ✓
3. C low heritability and high environmental influence ✓
4. D clear disease resistance scoring ✓

Mass selection is most commonly based on selecting plants by

1. A DNA sequencing of every plant only ✓
2. B phenotype in a population ✓
3. C haploid chromosome doubling only ✓
4. D cytoplasmic sterility restoration only ✓

Pedigree breeding differs from bulk breeding because pedigree breeding keeps

1. A all segregating seed mixed until release ✓
2. B only male sterile plants ✓
3. C individual plant ancestry records ✓
4. D no selection before variety release ✓

The bulk method in self-pollinated crops delays intensive selection mainly until

1. A F1 plants are harvested individually only ✓
2. B the original parents are lost ✓
3. C chromosomes are doubled chemically ✓
4. D later segregating generations become more homozygous ✓

Backcross breeding is most suitable for transferring

1. A one or a few specific genes into an adapted variety ✓
2. B all traits of a wild species without selection ✓
3. C only cytoplasmic characters with no nuclear genes ✓
4. D random mutations into every chromosome ✓

In backcross breeding, the parent repeatedly crossed to the hybrid progeny is called the

1. A donor parent ✓
2. B recurrent parent ✓
3. C tester parent only ✓
4. D mutant parent ✓

The donor parent in backcross breeding supplies

1. A the entire commercial genetic background ✓
2. B only the seed certification label ✓
3. C the field isolation distance ✓
4. D the target gene or trait to be transferred ✓

Heterosis is best defined as the superiority of a hybrid over its parents for

1. A seed moisture only ✓
2. B chromosome staining only ✓
3. C one or more traits ✓
4. D field plot size only ✓

Inbred lines in maize are developed mainly by repeated

1. A self-pollination and selection ✓
2. B open pollination without selection ✓
3. C vegetative propagation only ✓
4. D seed mixing after harvest ✓

Combining ability is evaluated to identify parents useful for

1. A soil erosion control ✓
2. B hybrid breeding ✓
3. C seed drying only ✓
4. D weed classification ✓

General combining ability is mainly associated with

1. A only maternal environment ✓
2. B seed coat thickness alone ✓
3. C additive gene effects ✓
4. D storage insect damage ✓

Specific combining ability is mainly associated with

1. A seed germination percentage only ✓
2. B variety naming rules ✓
3. C field irrigation schedule ✓
4. D non-additive gene effects ✓

Narrow-sense heritability is the ratio of additive genetic variance to

1. A phenotypic variance ✓
2. B environmental variance only ✓
3. C dominance variance only ✓
4. D error degrees of freedom ✓

Broad-sense heritability includes

1. A only additive variance ✓
2. B only environmental variance ✓
3. C additive, dominance and epistatic genetic variance ✓
4. D only seed weight variance ✓

Genetic advance under selection depends directly on selection intensity, heritability and

1. A seed bag color ✓
2. B phenotypic standard deviation ✓
3. C number of irrigation channels ✓
4. D pesticide label size ✓

Recurrent selection is mainly used to improve

1. A only the color of certified tags ✓
2. B seed moisture in a warehouse ✓
3. C the botanical name of a crop ✓
4. D the frequency of favorable genes in a population ✓

In cross-pollinated crops, synthetic varieties are produced by intercrossing

1. A only one pure line for many generations ✓
2. B selected lines or clones with good combining ability ✓
3. C seed from unrelated weed species ✓
4. D sterilized grains in storage ✓

Composite varieties are generally formed by mixing

1. A several genotypes without detailed combining ability testing ✓
2. B only one doubled haploid line ✓
3. C pollen from sterile plants only ✓
4. D seed lots after certification failure ✓

Mutation breeding is especially useful for creating

1. A immediate field certification labels ✓
2. B soil fertility without fertilizers ✓
3. C new variability for specific traits ✓
4. D water inside dry seed lots ✓

A common chemical mutagen used in crop improvement is

1. A sodium chloride ✓
2. B calcium carbonate ✓
3. C urea fertilizer ✓
4. D ethyl methane sulphonate ✓

Colchicine is used in plant breeding mainly to induce

1. A polyploidy ✓
2. B seed dormancy only ✓
3. C male fertility restoration only ✓
4. D pollen shedding in maize only ✓

A doubled haploid plant is valuable because it is

1. A always sterile and unusable ✓
2. B completely homozygous in one generation ✓
3. C genetically identical to both parents at once ✓
4. D a mixture of many open-pollinated lines ✓

Marker-assisted selection uses molecular markers linked with

1. A seed bag weight only ✓
2. B leaf color of all weeds ✓
3. C genes or quantitative trait loci of interest ✓
4. D market price of grain ✓

The final step before release of a new variety normally includes

1. A ignoring seed multiplication ✓
2. B removing all field data ✓
3. C mixing it with unknown varieties ✓
4. D testing for yield, adaptation, quality and distinctness ✓

A QTL is a genomic region associated with variation in a

1. A seed certification fee ✓
2. B single storage bag ✓
3. C field map scale ✓
4. D quantitative trait ✓

Linkage reduces recombination between genes located

1. A on different planets ✓
2. B only in cytoplasm ✓
3. C close together on the same chromosome ✓
4. D in separate seed bags ✓

Crossing over occurs during

1. A prophase I of meiosis ✓
2. B metaphase of mitosis only ✓
3. C seed drying ✓
4. D fertilizer application ✓

Cytoplasmic inheritance is usually transmitted mainly through the

1. A male parent only ✓
2. B female parent ✓
3. C seed certifying officer ✓
4. D pollination bag ✓

Cytoplasmic male sterility is widely used in

1. A seed drying only ✓
2. B soil classification ✓
3. C weed herbarium preparation ✓
4. D hybrid seed production ✓

Self-incompatibility helps maintain cross-pollination by preventing

1. A self-fertilization ✓
2. B seed germination ✓
3. C chlorophyll formation ✓
4. D root nodulation ✓

A line x tester analysis is primarily used to estimate

1. A seed moisture in storage only ✓
2. B combining ability of parents and crosses ✓
3. C soil organic matter only ✓
4. D plant taxonomy alone ✓

A diallel cross involves crossing

1. A one parent only with itself forever ✓
2. B seed lots from different warehouses ✓
3. C only sterile plants with no testers ✓
4. D a set of parents in all possible or selected combinations ✓

Genotype by environment interaction means that genotypes

1. A have no response to climate ✓
2. B are always identical in every location ✓
3. C perform differently across environments ✓
4. D cannot be selected in field trials ✓

Multi-location trials are conducted mainly to test

1. A adaptability and stability of candidate varieties ✓
2. B seed color under one lamp ✓
3. C laboratory glassware accuracy ✓
4. D pesticide brand popularity ✓

The Hardy-Weinberg equilibrium describes gene and genotype frequencies in a population with

1. A complete selection every generation ✓
2. B constant mutation pressure only ✓
3. C random mating and no evolutionary forces ✓
4. D only vegetative propagation ✓

Epistasis occurs when

1. A all genes assort independently forever ✓
2. B one gene masks or modifies the expression of another gene ✓
3. C a seed loses moisture in storage ✓
4. D a plant grows without chromosomes ✓

Incomplete dominance produces an F2 genotypic and phenotypic ratio of

1. A 3:1 ✓
2. B 9:3:3:1 ✓
3. C 1:1:1:1 ✓
4. D 1:2:1 ✓

Male sterile, maintainer and restorer lines are commonly denoted as

1. A A, B and R lines ✓
2. B P, Q and Z lines ✓
3. C X, Y and W lines ✓
4. D M, N and O lines ✓

Wide hybridization in plant breeding means crossing

1. A distantly related species or genera ✓
2. B two plants of the same pure line only ✓
3. C seed with fertilizer granules ✓
4. D two identical clones only ✓

Embryo rescue is used after wide crosses mainly to

1. A measure seed moisture quickly ✓
2. B destroy all hybrid seedlings ✓
3. C save hybrid embryos that would otherwise abort ✓
4. D increase storage fungi ✓

Participatory plant breeding involves active selection and evaluation by

1. A seed bags only ✓
2. B weather stations only ✓
3. C fertilizer factories only ✓
4. D farmers and other end users ✓

Genomic selection differs from marker-assisted selection because it uses

1. A genome-wide marker effects to predict breeding value ✓
2. B only one visible trait with no markers ✓
3. C seed lot purity labels only ✓
4. D chemical scarification of seed ✓

CRISPR-Cas systems are used in crop improvement mainly for

1. A seed bag stitching ✓
2. B targeted genome editing ✓
3. C random field sampling only ✓
4. D soil texture classification ✓

Seed priming commercially aims to

1. A kill embryos ✓
2. B advance germination metabolism for faster emergence ✓
3. C raise moisture to unsafe storage levels permanently ✓
4. D change variety identity ✓

Field inspection during certification checks

1. A only mill recovery ✓
2. B only world prices ✓
3. C only tractor HP ✓
4. D isolation, roguing, and crop condition against standards ✓

Carry-over seed stocks require

1. A proper storage and retesting of germination before use ✓
2. B open rainy sheds ✓
3. C no labels ✓
4. D mixing all varieties ✓

The ultimate goal of linking breeding and seed systems is

1. A keeping varieties in genebanks only ✓
2. B preventing adoption ✓
3. C maximizing spurious seed ✓
4. D delivering improved genetics to farmers as quality seed ✓

Bt crops produce

1. A human insulin in all tissues always ✓
2. B insecticidal proteins from Bacillus thuringiensis genes ✓
3. C only herbicide only without insects ✓
4. D viral coat proteins only always ✓

GMO crops contain

1. A only conventionally crossed genes always ✓
2. B DNA modified by modern biotechnological methods ✓
3. C no DNA ✓
4. D only fertilizer coatings ✓

QTL means

1. A quality testing lab only ✓
2. B quantitative trait locus ✓
3. C quarantine trade license ✓
4. D queue time limit ✓

Marker-assisted selection uses

1. A only visual color of bags ✓
2. B only soil EC ✓
3. C DNA markers linked to traits to aid selection ✓
4. D only canal duty ✓

Doubled haploids speed breeding by

1. A producing instantaneous homozygosity ✓
2. B increasing heterozygosity ✓
3. C preventing fixation ✓
4. D banning inbreds ✓

Tissue culture can enable

1. A rapid multiplication and some breeding support techniques ✓
2. B replacement of all field testing forever ✓
3. C creation of soil texture ✓
4. D canal lining ✓

Mutation breeding uses

1. A induced mutations to create new variation ✓
2. B only conventional crossing without novelty ✓
3. C only GM Agrobacterium always ✓
4. D only clonal cuttings ✓

Polyploidy involves

1. A more than two sets of chromosomes ✓
2. B haploid gametes only ✓
3. C zero chromosomes ✓
4. D only mitochondrial DNA ✓

CMS means

1. A certified moisture standard ✓
2. B cotton milling standard ✓
3. C cytoplasmic male sterility ✓
4. D canal management system ✓

Male sterility systems help

1. A increase selfing in wheat always ✓
2. B hybrid seed production without hand emasculation ✓
3. C stop all pollination worldwide ✓
4. D eliminate seed industry ✓

Emasculation is

1. A removal of anthers to prevent self-pollen in crossing ✓
2. B removal of roots ✓
3. C seed priming ✓
4. D ginning lint ✓

Cross-pollinated crops include

1. A wheat exclusively ✓
2. B maize, many brassicas and lucerne ✓
3. C rice exclusively ✓
4. D chickpea exclusively ✓

Self-pollinated crops include

1. A maize exclusively ✓
2. B only rye always ✓
3. C wheat, rice and chickpea (largely) ✓
4. D only castor always ✓

Open-pollinated varieties (OPVs) of maize

1. A are always sterile ✓
2. B can be farm-saved with less heterosis than hybrids ✓
3. C cannot be replanted ✓
4. D are identical to single-cross hybrids ✓

A single cross hybrid is

1. A a mixture of 10 landraces ✓
2. B F1 of two inbred lines ✓
3. C an open-pollinated variety only ✓
4. D a clonal orchard ✓

Inbreeding depression is

1. A increased vigor from selfing always ✓
2. B reduced performance from increasing homozygosity in cross-pollinated crops ✓
3. C only a soil problem ✓
4. D only a fertilizer issue ✓

Heterosis is

1. A inferiority of hybrids ✓
2. B loss of all vigor ✓
3. C superiority of hybrid over parents ✓
4. D only inbreeding depression ✓

Hybrid varieties exploit

1. A complete homozygosity only ✓
2. B only mutation breeding ✓
3. C heterosis (hybrid vigor) ✓
4. D only polyploidy without crossing ✓

Recurrent parent in backcrossing is

1. A the elite variety being improved ✓
2. B the donor of a single trait only ✓
3. C a weed ✓
4. D a fertilizer ✓

Backcross breeding is used mainly to

1. A create maximum diversity randomly ✓
2. B eliminate the recurrent parent genome entirely always ✓
3. C transfer a few genes into an elite recurrent parent ✓
4. D avoid all selection ✓

Bulk breeding delays individual selection until

1. A the F1 only ✓
2. B later generations after advancing a bulk population ✓
3. C before crossing ✓
4. D after commercial release only ✓

Pedigree breeding keeps

1. A no family records ✓
2. B only bulk harvest without notes ✓
3. C records of parent-progeny relationships during inbreeding ✓
4. D only marketing slogans ✓

Pure line selection is classical for

1. A only highly cross-pollinated crops exclusively ✓
2. B only clonally propagated banana always ✓
3. C only forest trees ✓
4. D self-pollinated crops to extract uniform lines ✓

Mass selection involves

1. A selecting plants based on phenotype and bulking seed ✓
2. B only molecular markers without plants ✓
3. C only tissue culture ✓
4. D only GM transformation ✓

Selection in breeding is

1. A random harvest without evaluation ✓
2. B choosing superior plants/lines as parents or varieties ✓
3. C only discarding all diversity ✓
4. D banning trials ✓

Heritability estimates

1. A only rainfall share of yield ✓
2. B market share of a brand ✓
3. C soil sand percentage ✓
4. D the proportion of phenotypic variance due to genetic variance ✓

Genotype × environment interaction matters because

1. A all varieties rank identically everywhere ✓
2. B environment never affects yield ✓
3. C variety ranking can change across locations/years ✓
4. D genetics are irrelevant ✓

Phenotype is

1. A DNA sequence alone ✓
2. B only pedigree name ✓
3. C only seed bag color ✓
4. D the observable expression of genotype plus environment ✓

Heterozygous means

1. A alleles are identical ✓
2. B chromosomes are absent ✓
3. C alleles at a locus differ ✓
4. D only cytoplasmic genes exist ✓

Homozygous means

1. A alleles differ ✓
2. B no genes present ✓
3. C only polyploidy ✓
4. D both alleles at a locus are identical ✓

Alleles are

1. A different crop species always ✓
2. B soil particles ✓
3. C irrigation methods ✓
4. D alternative forms of a gene ✓

A gene is

1. A a hereditary unit of DNA that influences traits ✓
2. B a fertilizer molecule ✓
3. C a soil horizon ✓
4. D a canal outlet ✓

Mendel's laws describe

1. A only soil texture inheritance ✓
2. B only irrigation scheduling ✓
3. C only market prices ✓
4. D segregation and independent assortment of genes ✓

Landraces are

1. A traditional farmer varieties adapted to local conditions ✓
2. B only modern hybrids ✓
3. C only GM events ✓
4. D only pure chemical lines ✓

A variety (cultivar) is

1. A any wild plant ✓
2. B only a weed biotype ✓
3. C a cultivated genotype released for production ✓
4. D a fertilizer grade ✓

Plant breeding aims to

1. A improve crop varieties for yield, quality and stress resistance ✓
2. B only preserve wild weeds ✓
3. C eliminate all genetic variation ✓
4. D ban cultivar release ✓

Germplasm is

1. A genetic material of plants conserved for breeding and research ✓
2. B only inert seed dust ✓
3. C only fertilizer prills ✓
4. D only irrigation water ✓

Bread wheat is

1. A a diploid like rice always ✓
2. B a haploid weed ✓
3. C a bacterial genome ✓
4. D an allohexaploid ✓

Combining ability analysis helps

1. A only soil test interpretation ✓
2. B choose parents for hybrid breeding ✓
3. C only irrigation duty ✓
4. D only ginning outturn ✓

Hybrid seed of maize must generally be

1. A farm-saved F2 without yield loss always ✓
2. B purchased fresh each season for full heterosis ✓
3. C produced by selfing the hybrid ✓
4. D identical to OPV farm seed ✓

Seed treatment with fungicides/insecticides aims to

1. A increase genetic purity ✓
2. B change ploidy ✓
3. C protect seedlings from early pests and diseases ✓
4. D replace certification ✓

Isolation distance in seed production prevents

1. A rainfall ✓
2. B unwanted pollen contamination ✓
3. C soil erosion ✓
4. D fertilizer drift only ✓

Roguing in seed fields removes

1. A all healthy plants ✓
2. B only weeds after harvest ✓
3. C off-types, diseased and objectionable plants ✓
4. D soil stones only ✓

Seed dormancy is

1. A immediate 100% germination always ✓
2. B only a soil salinity term ✓
3. C only hybrid vigor ✓
4. D failure to germinate under favorable conditions until dormancy breaks ✓

Recalcitrant seeds

1. A store like wheat for decades easily ✓
2. B are all cereals ✓
3. C do not tolerate much drying/cold storage ✓
4. D are only synthetic ✓

Orthodox seeds can be

1. A dried and stored at low temperature for long periods ✓
2. B killed by any drying ✓
3. C only recalcitrant forever ✓
4. D unable to enter genebanks ✓

Seed moisture content for safe storage should generally be

1. A above 30% always ✓
2. B saturated like grain in rain ✓
3. C irrelevant to storage ✓
4. D low enough to limit mold and insect activity (crop-specific) ✓

Seed vigor relates to

1. A only laboratory darkness failure ✓
2. B ability to emerge well under a range of field stresses ✓
3. C only color of seed coat ✓
4. D only bag size ✓

Seed germination percentage indicates

1. A proportion of seeds producing normal seedlings under test ✓
2. B only seed weight ✓
3. C only moisture of soil ✓
4. D only lint outturn ✓

Truthful labeled seed means

1. A unlabeled grain ✓
2. B seed without germination info always ✓
3. C quality declared by the producer on the label under law ✓
4. D only breeder seed ✓

Breeder seed is

1. A nucleus seed of highest genetic purity from the breeding institution ✓
2. B certified seed sold in villages only ✓
3. C grain from combine sweepings ✓
4. D F2 of a hybrid ✓

Genetic purity differs from physical purity in that genetic purity concerns

1. A trueness to variety versus inert matter/other crop seeds ✓
2. B only moisture ✓
3. C only germination warmth ✓
4. D only bag weight ✓

Foundation seed is

1. A the lowest quality class ✓
2. B only grain for flour ✓
3. C hybrid F2 farm grain ✓
4. D progeny of breeder seed used to produce certified seed ✓

Seed Act / rules in Pakistan regulate

1. A seed quality, labeling and certification aspects ✓
2. B only canal warabandi ✓
3. C only sugar recovery ✓
4. D only cotton ginning outturn ✓

Certified seed is

1. A any grain from the market ✓
2. B farm-saved without standards always ✓
3. C seed produced under an official certification scheme meeting standards ✓
4. D only dead seed ✓

Federal Seed Certification & Registration Department (FSC&RD) is associated with

1. A building barrages ✓
2. B seed certification and variety registration functions ✓
3. C setting wheat support price alone ✓
4. D cotton textile quotas only ✓

Variety registration/release typically requires

1. A a single unreplicated plot only ✓
2. B no data ✓
3. C multi-location evaluation of performance and distinctness ✓
4. D only a trade name ✓

Seed technology deals with

1. A only irrigation design ✓
2. B only soil taxonomy ✓
3. C only mill recovery ✓
4. D production, processing, storage, testing and quality of seed ✓

CRISPR gene editing differs from classical transgenics often by

1. A always inserting Bt genes ✓
2. B being identical to mutation only without tools ✓
3. C requiring no DNA knowledge ✓
4. D enabling targeted edits that may not insert foreign genes ✓

Participatory plant breeding involves

1. A excluding farmers from all trials ✓
2. B only lab work ✓
3. C only GM labs abroad ✓
4. D farmers in selection and evaluation ✓

Ideotype breeding designs

1. A random plants without goals ✓
2. B only weed ideotypes ✓
3. C model plant types thought to maximize yield in a target environment ✓
4. D only soil profiles ✓

Refuge strategy with Bt crops aims to

1. A maximize resistance speed ✓
2. B eliminate non-Bt plantings ✓
3. C ban IPM ✓
4. D delay insect resistance evolution ✓

Biosafety concerns for GMOs include

1. A only seed bag color ✓
2. B gene flow, resistance evolution and food/environmental safety assessment ✓
3. C only tractor brand ✓
4. D only market holidays ✓

Herbicide-tolerant GM crops allow

1. A use of specific herbicides over the crop ✓
2. B immunity to all chemicals forever ✓
3. C drought elimination ✓
4. D salt removal from soil ✓

Wide hybridization crosses

1. A only identical clones ✓
2. B only selfing one flower ✓
3. C only mutation without crossing ✓
4. D different species/genera to introgress traits ✓

Transgressive segregation produces

1. A only mid-parent values always ✓
2. B progeny outside parental phenotypic ranges ✓
3. C no variation ✓
4. D only maternal phenotypes ✓