Category: Genetics and Plant Breeding Definitions A to Z
A – Genetics and Plant Breeding definitions
By Agritests |
27 Jun, 2026
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A Chromosome. Any member of the normal chromosome complement in contrast to the B-chromosomes. A Line. The male-sterile parent line to produce hybrid seed. It is the seed-producing line, always used as the female parent. It has ‘sterile’ cytoplasm and recessive nuclear gene(s). A line: The seed-bearing parent line used to produce hybrid seed that is male sterile […]
Z – Genetics and Plant Breeding definitions
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27 Jun, 2026
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Z chromosome: A sex chromosome that is limited to the male sex Z Test. A statistical test of significance for difference between means of large samples(>30). It is supposed that z-test is not affected by sampling error that must remain inthe estimation of population standard deviation due to small size of samples in t-test. zDNA: A left-handed, alternate form of […]
Y – Genetics and Plant Breeding definitions
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27 Jun, 2026
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Y chromosome: Plays a role in sex determination. Y Linkage. The inheritance pattern of genes found on the Y chromosome. Thus far, onlya few genes have been reported to have their association on the Y chromosome. Yeast artificial chromosome (YAC): A vector used to clone DNA fragments (upto 400 kb); it is constructed from the telomeric, centromeric, and […]
X – Genetics and Plant Breeding definitions
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27 Jun, 2026
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X Chromosome Inactivation. The process by which the genes of an X chromosome in amammal can be completely repressed as a part of the dosage compensationmechanism. Such an inactivated chromosome is referred to as a Barr body. X chromosome: A sex chromosome found in a double dose in the homogameticsex and in a single dose in the heterogametic sex. […]
W – Genetics and Plant Breeding definitions
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27 Jun, 2026
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Wallace EffectThe process of selection for reproductive isolation. Water index The ratio of R900 to R970, where R900 and R970 are reflectance at 900 and 970 nm, respectively. Waterlogging Stress A stress imposed to plants by continued stagnation of water. Somecrop plants, for example rice, tolerate waterlogging stress by virtue of their specialcharacters (presence of aerenchymatous cells). […]
V – Genetics and Plant Breeding Definitions
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27 Jun, 2026
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Vacuole. Any of the large, transparent vesicles limited by a unit membrane in mature plant cells. Vacuoles are filled with a dilute solution, called cell sap. In meristematic tissues, vacuoles are numerous and small. Validation of marker–trait linkage: Evaluation of the observed marker–trait linkage in a fairly large number of unrelated germplasms showing variation for the […]
U – Genetics and Plant Breeding definitions
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27 Jun, 2026
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U’s Triangle (U 1935). A triangle that depicts three basic diploid species (one each at each end) and three amphidiploid species (one each at the middle of each side) of Brassicas showing phylogenetic relationship of each alloploid species with the parental diploid species. The three basic species are B. nigra (n = 8), B. oleracea (n =9), and B. campestris (n = 10). It is […]
T – Genetics and Plant Breeding definitions
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27 Jun, 2026
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Tag oligonucleotide In SNP genotyping, a unique oligonucleotide unrelated to the sequences of the locus to be genotyped; each tag oligo is attached to a known position on the microarray/chip. Tagging. The use of a piece of foreign DNA or a transposon to label a gene so that aclone of that gene can be identified readily in […]
S – Genetics and Plant Breeding definitions
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27 Jun, 2026
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S Phase. The part of interphase of the cell cycle in which DNA synthesis occurs. S. Svedberg unit; a unit of sedimentation velocity that is commonly used to describemolecular units of various sizes as sedimentation velocity is proportional to the size. S0. Symbol used to designate the original selfed plant. S1, S2, S3… Symbols used to designate first, second, […]
R – Genetics and Plant Breeding definitions
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27 Jun, 2026
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R Plasmid. A plasmid containing one or several transposons that bear resistance genes. Race. A population or aggregate of populations with characteristic gene frequencies thatdistinguishes it from any other such groups within formally recognizable subspeciesor species. It is essentially an intraspecific category. Differences between races areonly relative and not absolute. Any race is able to interbreed freely with any […]