Glossary Plant Breeding

frequency, if there is no difference in gene frequency between donor and recipient
population.
Mini Core. See core collection.
Minimal Medium. A medium containing only a carbon source (sugar), inorganic salts
and water.
Minisatellite. A type of repetitive DNA sequence based on short repeat sequences with a
unique common core. It is used for DNA fingerprinting.
Mispairing. The presence of a non-complementary nucleotide at a given position in one
of the polynucleotide chains of a DNA double helix. It may lead to a gene mutation.
Missense Mutation. A mutation that alters a codon in such away that it encodes a
different amino acid, for example, GAA (glutamic acid) to GUA (valine). This
change, which occurs in the B polypeptide chain at 6 th amino acid position, causes
sickle cell anaemia in human population.
Missing Plot Technique. A technique to calculate the value of any missing treatment in
any block (replication). The calculation for any missing value (x) is done as: x = [r Bj
+ t Ti – GT / (r-1) (t-1)]; whereas, r = no. of replication, t = no. of treatments, Bj =
known jth block total where x is missing, Ti = known treatment total for which x is
missing, and GT = grand total with missing observation. Missing plot technique is an
advantage for a randomised complete block design.
Mitochondrion. A eukaryotic cell organelle that is the site of ATP synthesis, and of the
citric acid cycle. It is a small body usually with distinct shelf like internal layers. It
provides energy through respiration and oxidation.
Mitogen. Any substance that stimulates cells to undergo mitosis.
Mitosis. A kind of cell division in which the nucleus is divided into two daughter nuclei
with equivalent chromosome complements. It is a conservative process that maintains
the same chromosome number in the daughter cells compared to the parental one. It
occurs in both somatic as well as reproductive cells.
MitoticCrossover(Stern 1943). A crossover resulting from the pairing of homologs
during mitosis; also called somatic crossover. Like meiosis, it takes place in fourstrand
stage of chromosomes. The outcomes of somatic crossing-over depend upon:
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