Plant Breeding: Genetics and Breeding Methods MCQs 2026

A line x tester analysis is primarily used to estimate

1. Aseed moisture in storage only✓
2. Bcombining ability of parents and crosses✓
3. Csoil organic matter only✓
4. Dplant taxonomy alone✓

Genotype by environment interaction means that genotypes

1. Ahave no response to climate✓
2. Bare always identical in every location✓
3. Cperform differently across environments✓
4. Dcannot be selected in field trials✓

Multi-location trials are conducted mainly to test

1. Aadaptability and stability of candidate varieties✓
2. Bseed color under one lamp✓
3. Claboratory glassware accuracy✓
4. Dpesticide brand popularity✓

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

1. Acomplete selection every generation✓
2. Bconstant mutation pressure only✓
3. Crandom mating and no evolutionary forces✓
4. Donly vegetative propagation✓

Epistasis occurs when

1. Aall genes assort independently forever✓
2. Bone gene masks or modifies the expression of another gene✓
3. Ca seed loses moisture in storage✓
4. Da plant grows without chromosomes✓

Incomplete dominance produces an F2 genotypic and phenotypic ratio of

1. A3:1✓
2. B9:3:3:1✓
3. C1:1:1:1✓
4. D1:2:1✓

Transgressive segregation refers to progeny that

1. Ashow no genetic variation at all✓
2. Bexceed the range of both parents for a trait✓
3. Care always sterile hybrids✓
4. Dcontain only cytoplasmic genes✓

Wide hybridization in plant breeding means crossing

1. Adistantly related species or genera✓
2. Btwo plants of the same pure line only✓
3. Cseed with fertilizer granules✓
4. Dtwo identical clones only✓

Embryo rescue is used after wide crosses mainly to

1. Ameasure seed moisture quickly✓
2. Bdestroy all hybrid seedlings✓
3. Csave hybrid embryos that would otherwise abort✓
4. Dincrease storage fungi✓

Participatory plant breeding involves active selection and evaluation by

1. Aseed bags only✓
2. Bweather stations only✓
3. Cfertilizer factories only✓
4. Dfarmers and other end users✓

Genomic selection differs from marker-assisted selection because it uses

1. Agenome-wide marker effects to predict breeding value✓
2. Bonly one visible trait with no markers✓
3. Cseed lot purity labels only✓
4. Dchemical scarification of seed✓

CRISPR-Cas systems are used in crop improvement mainly for

1. Aseed bag stitching✓
2. Btargeted genome editing✓
3. Crandom field sampling only✓
4. Dsoil texture classification✓

Male sterile, maintainer and restorer lines are commonly denoted as

1. AA, B and R lines✓
2. BP, Q and Z lines✓
3. CX, Y and W lines✓
4. DM, N and O lines✓

Pure line varieties are generally most suitable for

1. Aobligate cross-pollinated crops only✓
2. Bself-pollinated crops✓
3. Cseedless crops only✓
4. Dperennial forest trees only✓

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

1. Agene✓
2. Bchromatid✓
3. Cgamete✓
4. Dzygote✓

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

1. Adihybrid cross✓
2. Bmonohybrid cross✓
3. Ctest cross✓
4. Dbackcross✓

The phenotypic ratio of a typical Mendelian monohybrid F2 generation is

1. A1:2:1✓
2. B9:3:3:1✓
3. C3:1✓
4. D1:1✓

A test cross is made by crossing an individual with a

1. Ahomozygous dominant parent✓
2. Bheterozygous dominant parent only✓
3. Cpolyploid parent only✓
4. Dhomozygous recessive parent✓

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

1. Apure line selection✓
2. Bmass selection without progeny testing✓
3. Csynthetic variety development✓
4. Dtopcross testing only✓

Selection is least effective for traits with

1. Ahigh heritability and large variation✓
2. Bsimple qualitative inheritance✓
3. Clow heritability and high environmental influence✓
4. Dclear disease resistance scoring✓

Mass selection is most commonly based on selecting plants by

1. ADNA sequencing of every plant only✓
2. Bphenotype in a population✓
3. Chaploid chromosome doubling only✓
4. Dcytoplasmic sterility restoration only✓

Pedigree breeding differs from bulk breeding because pedigree breeding keeps

1. Aall segregating seed mixed until release✓
2. Bonly male sterile plants✓
3. Cindividual plant ancestry records✓
4. Dno selection before variety release✓

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

1. AF1 plants are harvested individually only✓
2. Bthe original parents are lost✓
3. Cchromosomes are doubled chemically✓
4. Dlater segregating generations become more homozygous✓

Backcross breeding is most suitable for transferring

1. Aone or a few specific genes into an adapted variety✓
2. Ball traits of a wild species without selection✓
3. Conly cytoplasmic characters with no nuclear genes✓
4. Drandom mutations into every chromosome✓

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

1. Adonor parent✓
2. Brecurrent parent✓
3. Ctester parent only✓
4. Dmutant parent✓

The donor parent in backcross breeding supplies

1. Athe entire commercial genetic background✓
2. Bonly the seed certification label✓
3. Cthe field isolation distance✓
4. Dthe target gene or trait to be transferred✓

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

1. Aseed moisture only✓
2. Bchromosome staining only✓
3. Cone or more traits✓
4. Dfield plot size only✓

Inbred lines in maize are developed mainly by repeated

1. Aself-pollination and selection✓
2. Bopen pollination without selection✓
3. Cvegetative propagation only✓
4. Dseed mixing after harvest✓

Combining ability is evaluated to identify parents useful for

1. Asoil erosion control✓
2. Bhybrid breeding✓
3. Cseed drying only✓
4. Dweed classification✓

General combining ability is mainly associated with

1. Aonly maternal environment✓
2. Bseed coat thickness alone✓
3. Cadditive gene effects✓
4. Dstorage insect damage✓

Specific combining ability is mainly associated with

1. Aseed germination percentage only✓
2. Bvariety naming rules✓
3. Cfield irrigation schedule✓
4. Dnon-additive gene effects✓

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

1. Aphenotypic variance✓
2. Benvironmental variance only✓
3. Cdominance variance only✓
4. Derror degrees of freedom✓

Broad-sense heritability includes

1. Aonly additive variance✓
2. Bonly environmental variance✓
3. Cadditive, dominance and epistatic genetic variance✓
4. Donly seed weight variance✓

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

1. Aseed bag color✓
2. Bphenotypic standard deviation✓
3. Cnumber of irrigation channels✓
4. Dpesticide label size✓

Recurrent selection is mainly used to improve

1. Aonly the color of certified tags✓
2. Bseed moisture in a warehouse✓
3. Cthe botanical name of a crop✓
4. Dthe frequency of favorable genes in a population✓

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

1. Aonly one pure line for many generations✓
2. Bselected lines or clones with good combining ability✓
3. Cseed from unrelated weed species✓
4. Dsterilized grains in storage✓

Composite varieties are generally formed by mixing

1. Aseveral genotypes without detailed combining ability testing✓
2. Bonly one doubled haploid line✓
3. Cpollen from sterile plants only✓
4. Dseed lots after certification failure✓

Mutation breeding is especially useful for creating

1. Aimmediate field certification labels✓
2. Bsoil fertility without fertilizers✓
3. Cnew variability for specific traits✓
4. Dwater inside dry seed lots✓

A common chemical mutagen used in crop improvement is

1. Asodium chloride✓
2. Bcalcium carbonate✓
3. Curea fertilizer✓
4. Dethyl methane sulphonate✓

Colchicine is used in plant breeding mainly to induce

1. Apolyploidy✓
2. Bseed dormancy only✓
3. Cmale fertility restoration only✓
4. Dpollen shedding in maize only✓

A doubled haploid plant is valuable because it is

1. Aalways sterile and unusable✓
2. Bcompletely homozygous in one generation✓
3. Cgenetically identical to both parents at once✓
4. Da mixture of many open-pollinated lines✓

Marker-assisted selection uses molecular markers linked with

1. Aseed bag weight only✓
2. Bleaf color of all weeds✓
3. Cgenes or quantitative trait loci of interest✓
4. Dmarket price of grain✓

The final step before release of a new variety normally includes

1. Aignoring seed multiplication✓
2. Bremoving all field data✓
3. Cmixing it with unknown varieties✓
4. Dtesting for yield, adaptation, quality and distinctness✓

A QTL is a genomic region associated with variation in a

1. Aseed certification fee✓
2. Bsingle storage bag✓
3. Cfield map scale✓
4. Dquantitative trait✓

Linkage reduces recombination between genes located

1. Aon different planets✓
2. Bonly in cytoplasm✓
3. Cclose together on the same chromosome✓
4. Din separate seed bags✓

Crossing over occurs during

1. Aprophase I of meiosis✓
2. Bmetaphase of mitosis only✓
3. Cseed drying✓
4. Dfertilizer application✓

Cytoplasmic inheritance is usually transmitted mainly through the

1. Amale parent only✓
2. Bfemale parent✓
3. Cseed certifying officer✓
4. Dpollination bag✓

Cytoplasmic male sterility is widely used in

1. Aseed drying only✓
2. Bsoil classification✓
3. Cweed herbarium preparation✓
4. Dhybrid seed production✓

Self-incompatibility helps maintain cross-pollination by preventing

1. Aself-fertilization✓
2. Bseed germination✓
3. Cchlorophyll formation✓
4. Droot nodulation✓

A diallel cross involves crossing

1. Aone parent only with itself forever✓
2. Bseed lots from different warehouses✓
3. Conly sterile plants with no testers✓
4. Da set of parents in all possible or selected combinations✓

Seed priming commercially aims to

1. Akill embryos✓
2. Badvance germination metabolism for faster emergence✓
3. Craise moisture to unsafe storage levels permanently✓
4. Dchange variety identity✓

Field inspection during certification checks

1. Aonly mill recovery✓
2. Bonly world prices✓
3. Conly tractor HP✓
4. Disolation, roguing, and crop condition against standards✓

Carry-over seed stocks require

1. Aproper storage and retesting of germination before use✓
2. Bopen rainy sheds✓
3. Cno labels✓
4. Dmixing all varieties✓

The ultimate goal of linking breeding and seed systems is

1. Akeeping varieties in genebanks only✓
2. Bpreventing adoption✓
3. Cmaximizing spurious seed✓
4. Ddelivering improved genetics to farmers as quality seed✓

Bt crops produce

1. Ahuman insulin in all tissues always✓
2. Binsecticidal proteins from Bacillus thuringiensis genes✓
3. Conly herbicide only without insects✓
4. Dviral coat proteins only always✓

GMO crops contain

1. Aonly conventionally crossed genes always✓
2. BDNA modified by modern biotechnological methods✓
3. Cno DNA✓
4. Donly fertilizer coatings✓

QTL means

1. Aquality testing lab only✓
2. Bquantitative trait locus✓
3. Cquarantine trade license✓
4. Dqueue time limit✓

Marker-assisted selection uses

1. Aonly visual color of bags✓
2. Bonly soil EC✓
3. CDNA markers linked to traits to aid selection✓
4. Donly canal duty✓

Doubled haploids speed breeding by

1. Aproducing instantaneous homozygosity✓
2. Bincreasing heterozygosity✓
3. Cpreventing fixation✓
4. Dbanning inbreds✓

Tissue culture can enable

1. Arapid multiplication and some breeding support techniques✓
2. Breplacement of all field testing forever✓
3. Ccreation of soil texture✓
4. Dcanal lining✓

Mutation breeding uses

1. Ainduced mutations to create new variation✓
2. Bonly conventional crossing without novelty✓
3. Conly GM Agrobacterium always✓
4. Donly clonal cuttings✓

Polyploidy involves

1. Amore than two sets of chromosomes✓
2. Bhaploid gametes only✓
3. Czero chromosomes✓
4. Donly mitochondrial DNA✓

CMS means

1. Acertified moisture standard✓
2. Bcotton milling standard✓
3. Ccytoplasmic male sterility✓
4. Dcanal management system✓

Male sterility systems help

1. Aincrease selfing in wheat always✓
2. Bhybrid seed production without hand emasculation✓
3. Cstop all pollination worldwide✓
4. Deliminate seed industry✓

Emasculation is

1. Aremoval of anthers to prevent self-pollen in crossing✓
2. Bremoval of roots✓
3. Cseed priming✓
4. Dginning lint✓

Cross-pollinated crops include

1. Awheat exclusively✓
2. Bmaize, many brassicas and lucerne✓
3. Crice exclusively✓
4. Dchickpea exclusively✓

Self-pollinated crops include

1. Amaize exclusively✓
2. Bonly rye always✓
3. Cwheat, rice and chickpea (largely)✓
4. Donly castor always✓

Open-pollinated varieties (OPVs) of maize

1. Aare always sterile✓
2. Bcan be farm-saved with less heterosis than hybrids✓
3. Ccannot be replanted✓
4. Dare identical to single-cross hybrids✓

A single cross hybrid is

1. Aa mixture of 10 landraces✓
2. BF1 of two inbred lines✓
3. Can open-pollinated variety only✓
4. Da clonal orchard✓

Inbreeding depression is

1. Aincreased vigor from selfing always✓
2. Breduced performance from increasing homozygosity in cross-pollinated crops✓
3. Conly a soil problem✓
4. Donly a fertilizer issue✓

Heterosis is

1. Ainferiority of hybrids✓
2. Bloss of all vigor✓
3. Csuperiority of hybrid over parents✓
4. Donly inbreeding depression✓

Hybrid varieties exploit

1. Acomplete homozygosity only✓
2. Bonly mutation breeding✓
3. Cheterosis (hybrid vigor)✓
4. Donly polyploidy without crossing✓

Recurrent parent in backcrossing is

1. Athe elite variety being improved✓
2. Bthe donor of a single trait only✓
3. Ca weed✓
4. Da fertilizer✓

Backcross breeding is used mainly to

1. Acreate maximum diversity randomly✓
2. Beliminate the recurrent parent genome entirely always✓
3. Ctransfer a few genes into an elite recurrent parent✓
4. Davoid all selection✓

Bulk breeding delays individual selection until

1. Athe F1 only✓
2. Blater generations after advancing a bulk population✓
3. Cbefore crossing✓
4. Dafter commercial release only✓

Pedigree breeding keeps

1. Ano family records✓
2. Bonly bulk harvest without notes✓
3. Crecords of parent-progeny relationships during inbreeding✓
4. Donly marketing slogans✓

Pure line selection is classical for

1. Aonly highly cross-pollinated crops exclusively✓
2. Bonly clonally propagated banana always✓
3. Conly forest trees✓
4. Dself-pollinated crops to extract uniform lines✓

Mass selection involves

1. Aselecting plants based on phenotype and bulking seed✓
2. Bonly molecular markers without plants✓
3. Conly tissue culture✓
4. Donly GM transformation✓

Selection in breeding is

1. Arandom harvest without evaluation✓
2. Bchoosing superior plants/lines as parents or varieties✓
3. Conly discarding all diversity✓
4. Dbanning trials✓

Heritability estimates

1. Aonly rainfall share of yield✓
2. Bmarket share of a brand✓
3. Csoil sand percentage✓
4. Dthe proportion of phenotypic variance due to genetic variance✓

Genotype × environment interaction matters because

1. Aall varieties rank identically everywhere✓
2. Benvironment never affects yield✓
3. Cvariety ranking can change across locations/years✓
4. Dgenetics are irrelevant✓

Phenotype is

1. ADNA sequence alone✓
2. Bonly pedigree name✓
3. Conly seed bag color✓
4. Dthe observable expression of genotype plus environment✓

Heterozygous means

1. Aalleles are identical✓
2. Bchromosomes are absent✓
3. Calleles at a locus differ✓
4. Donly cytoplasmic genes exist✓

Homozygous means

1. Aalleles differ✓
2. Bno genes present✓
3. Conly polyploidy✓
4. Dboth alleles at a locus are identical✓

Alleles are

1. Adifferent crop species always✓
2. Bsoil particles✓
3. Cirrigation methods✓
4. Dalternative forms of a gene✓

A gene is

1. Aa hereditary unit of DNA that influences traits✓
2. Ba fertilizer molecule✓
3. Ca soil horizon✓
4. Da canal outlet✓

Mendel's laws describe

1. Aonly soil texture inheritance✓
2. Bonly irrigation scheduling✓
3. Conly market prices✓
4. Dsegregation and independent assortment of genes✓

Landraces are

1. Atraditional farmer varieties adapted to local conditions✓
2. Bonly modern hybrids✓
3. Conly GM events✓
4. Donly pure chemical lines✓

A variety (cultivar) is

1. Aany wild plant✓
2. Bonly a weed biotype✓
3. Ca cultivated genotype released for production✓
4. Da fertilizer grade✓

Plant breeding aims to

1. Aimprove crop varieties for yield, quality and stress resistance✓
2. Bonly preserve wild weeds✓
3. Celiminate all genetic variation✓
4. Dban cultivar release✓

Germplasm is

1. Agenetic material of plants conserved for breeding and research✓
2. Bonly inert seed dust✓
3. Conly fertilizer prills✓
4. Donly irrigation water✓

Bread wheat is

1. Aa diploid like rice always✓
2. Ba haploid weed✓
3. Ca bacterial genome✓
4. Dan allohexaploid✓

Combining ability analysis helps

1. Aonly soil test interpretation✓
2. Bchoose parents for hybrid breeding✓
3. Conly irrigation duty✓
4. Donly ginning outturn✓

Hybrid seed of maize must generally be

1. Afarm-saved F2 without yield loss always✓
2. Bpurchased fresh each season for full heterosis✓
3. Cproduced by selfing the hybrid✓
4. Didentical to OPV farm seed✓

Seed treatment with fungicides/insecticides aims to

1. Aincrease genetic purity✓
2. Bchange ploidy✓
3. Cprotect seedlings from early pests and diseases✓
4. Dreplace certification✓

Isolation distance in seed production prevents

1. Arainfall✓
2. Bunwanted pollen contamination✓
3. Csoil erosion✓
4. Dfertilizer drift only✓

Roguing in seed fields removes

1. Aall healthy plants✓
2. Bonly weeds after harvest✓
3. Coff-types, diseased and objectionable plants✓
4. Dsoil stones only✓

Seed dormancy is

1. Aimmediate 100% germination always✓
2. Bonly a soil salinity term✓
3. Conly hybrid vigor✓
4. Dfailure to germinate under favorable conditions until dormancy breaks✓

Recalcitrant seeds

1. Astore like wheat for decades easily✓
2. Bare all cereals✓
3. Cdo not tolerate much drying/cold storage✓
4. Dare only synthetic✓

Orthodox seeds can be

1. Adried and stored at low temperature for long periods✓
2. Bkilled by any drying✓
3. Conly recalcitrant forever✓
4. Dunable to enter genebanks✓

Seed moisture content for safe storage should generally be

1. Aabove 30% always✓
2. Bsaturated like grain in rain✓
3. Cirrelevant to storage✓
4. Dlow enough to limit mold and insect activity (crop-specific)✓

Seed vigor relates to

1. Aonly laboratory darkness failure✓
2. Bability to emerge well under a range of field stresses✓
3. Conly color of seed coat✓
4. Donly bag size✓

Seed germination percentage indicates

1. Aproportion of seeds producing normal seedlings under test✓
2. Bonly seed weight✓
3. Conly moisture of soil✓
4. Donly lint outturn✓

Truthful labeled seed means

1. Aunlabeled grain✓
2. Bseed without germination info always✓
3. Cquality declared by the producer on the label under law✓
4. Donly breeder seed✓

Breeder seed is

1. Anucleus seed of highest genetic purity from the breeding institution✓
2. Bcertified seed sold in villages only✓
3. Cgrain from combine sweepings✓
4. DF2 of a hybrid✓

Genetic purity differs from physical purity in that genetic purity concerns

1. Atrueness to variety versus inert matter/other crop seeds✓
2. Bonly moisture✓
3. Conly germination warmth✓
4. Donly bag weight✓

Foundation seed is

1. Athe lowest quality class✓
2. Bonly grain for flour✓
3. Chybrid F2 farm grain✓
4. Dprogeny of breeder seed used to produce certified seed✓

Seed Act / rules in Pakistan regulate

1. Aseed quality, labeling and certification aspects✓
2. Bonly canal warabandi✓
3. Conly sugar recovery✓
4. Donly cotton ginning outturn✓

Certified seed is

1. Aany grain from the market✓
2. Bfarm-saved without standards always✓
3. Cseed produced under an official certification scheme meeting standards✓
4. Donly dead seed✓

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

1. Abuilding barrages✓
2. Bseed certification and variety registration functions✓
3. Csetting wheat support price alone✓
4. Dcotton textile quotas only✓

Variety registration/release typically requires

1. Aa single unreplicated plot only✓
2. Bno data✓
3. Cmulti-location evaluation of performance and distinctness✓
4. Donly a trade name✓

Seed technology deals with

1. Aonly irrigation design✓
2. Bonly soil taxonomy✓
3. Conly mill recovery✓
4. Dproduction, processing, storage, testing and quality of seed✓

CRISPR gene editing differs from classical transgenics often by

1. Aalways inserting Bt genes✓
2. Bbeing identical to mutation only without tools✓
3. Crequiring no DNA knowledge✓
4. Denabling targeted edits that may not insert foreign genes✓

Participatory plant breeding involves

1. Aexcluding farmers from all trials✓
2. Bonly lab work✓
3. Conly GM labs abroad✓
4. Dfarmers in selection and evaluation✓

Ideotype breeding designs

1. Arandom plants without goals✓
2. Bonly weed ideotypes✓
3. Cmodel plant types thought to maximize yield in a target environment✓
4. Donly soil profiles✓

Refuge strategy with Bt crops aims to

1. Amaximize resistance speed✓
2. Beliminate non-Bt plantings✓
3. Cban IPM✓
4. Ddelay insect resistance evolution✓

Biosafety concerns for GMOs include

1. Aonly seed bag color✓
2. Bgene flow, resistance evolution and food/environmental safety assessment✓
3. Conly tractor brand✓
4. Donly market holidays✓

Herbicide-tolerant GM crops allow

1. Ause of specific herbicides over the crop✓
2. Bimmunity to all chemicals forever✓
3. Cdrought elimination✓
4. Dsalt removal from soil✓

Wide hybridization crosses

1. Aonly identical clones✓
2. Bonly selfing one flower✓
3. Conly mutation without crossing✓
4. Ddifferent species/genera to introgress traits✓

Transgressive segregation produces

1. Aonly mid-parent values always✓
2. Bprogeny outside parental phenotypic ranges✓
3. Cno variation✓
4. Donly maternal phenotypes✓