Agriculture Reference
In-Depth Information
many arise. Mustard gas operates similarly [9]. Rapoport [6,9-11] explains the action
of ketonic connections and alkylating agents, when they penetrate in the cells, where
they interact with amino groups, what results in the irreversible changes of proteins
of cytoplasm and genic proteins. Thus recessive mutations appear mainly unlike the
breaks of chromosomes after a short-wave radiation [12]. In experiments with addi-
tion of chemical agents to the nutrient medium of culture of drosophila, the mutagen is
present there constantly. Rapoport supposed that the complex formation of chemicals
with proteins in cytoplasm and chromosomes determines the mutagenicity of these
connections.
This capacity of complex formation of chemical mutagens with proteins in a cell
predetermined the preservation of mutagens and caused appearance of mutations or
transpositions in a row of cellular generations.
Considerably later classic works of B.N. Sidorov and N.N. Sokolov on the seed-
lings of well-known cytogenetic object of
Crepis capillaris
have showed that a muta-
gen an ethylene imine causes new rearrangements of chromosomes in row of cellular
generations [13,14]. After treatment of seedlings, the mutagen were washed off by
tap water. These authors also showed that ethylene imine interacts in the cells with
biologically important substances, such as amino acids or the predecessors of DNA
[15]. These complexes are named as secondary mutagens by the authors. Hence, the
appearance of the new rearrangements of chromosomes in cell generations is named
as “the secondary mutagenesis.”
In the research studies [16,17], I.A. Rapport in detail analyzed the objective laws
of origin of the lethal mutations from alkylating agents, likeliness of effect of chemi-
cal and radiation mutagens, and fundamental distinction of the chemical mutagenesis
from the effect of the ionizing radiation. He made it clear that the supermutagens [18]
were provoking a large number of heritable changes. Research studies of Rapoport
have resulted in the method of chemical mutagenesis, which fi nds its application in
genetics, cytogenetics, and agriculture. Since 1959 Rapoport published collections
of scientifi c research studies of selectionists from the entire country. It is possible
to name last [19,20]. This method is used in large scientifi c collectives both in our
country and abroad. It also has application in experimental biology, microbiology,
agriculture, and medicine. By means of chemical mutagens the registered sorts of
agricultural cultures were created. For example, the cultivars of oat and barley were
created [21]. Eiges with collaborators created cultivars of winter wheat, which are the
Sibirskaja niva (Siberian fi eld), the Stavropolskaja kormovaja (Stavropol fodder), and
the Imeni Rapoporta (Name of Rapoport) [22] and perspective specimens, so plant-
breeding work proceeds with that.
Collections of research studies of Rapoport [16,17], topics on his activity [23,24],
and his fundamental theoretical works [25] were published posthumously. These pub-
lications were fulfi lled with the initiative and the participation of his wife who is a
doctor of biological sciences in O.G. Stroeva. To the century of A. Rapoport, con-
ferences and publications were devoted. Research studies with the use of chemical
mutagenesis methods continued, in particular in works of Eiges et al. [26], which have
large achievements in genetics, selection, and practical applications of this method on
the winter wheat mutants.
Search WWH ::
Custom Search