Studies on the embryogenic processes in the in vitro culture of wheat somatic tissues by using a proliferative antigen of initial cells
Nina V. Evseeva1*, Oksana V. Tkachenko2 ,Yuriy V. Lobachev2, Alexander Yu. Mitrophanov1, Taisia I. Djatchouk3 and Sergei Yu. Shchyogolev1
1Institute of Biochemistry and Physiology of Plants and
Microorganisms, Russian Academy of Sciences (IBPPM RAS), 13
Entuziastov Ave., Saratov 410015, Russia
2N.I. Vavilov Saratov State Agrarian University, 1
Teatralnaya Square, Saratov 410600, Russia
3Agricultural Research Institute of South-East Region, 7
Tulaikova Str., Saratov 410020, Russia
Summary
Embryogenic processes occurring in an in vitro culture of immature wheat (Triticum aestivum L.) embryos were studied using the proliferative antigen of initial cells, PAI -- a cell-division-associated molecular marker for apical meristematic cells of cereal crops. With an immunochemical test-system based on polyclonal, monospecific anti- PAI antibodies, we found a correlation between PAI content and the embryogenic potential of calli of the wheat cultivar Saratovskaya 29 and its near-isogenic lines differing in the Rht-B1c alleles. We discuss the possible association of PAI with the Rht genetic system and the prospects for using this marker in breeding and bioengineering programs to screen newly raised heat lines for their embryogenic capacity.
Key words: Triticum aestivum L., embryogenesis, proliferative antigen of initials, Rht gene, immunochemical analysis
Introduction
The genetic determination of morphogenetic processes taking place
in an in vitro culture of wheat somatic tissues is still an
open question. For a long time, the important role of genotype has
only been noted on the basis of cultivar and species differences in
the frequency of embryogenic-callus formation (Maddock et al. 1983;
Mathias 1990). Carman and Campbell (1990), analyzing monosomic and
chromosome-substituted lines, revealed individual chromosomes and
chromosomal regions involved in the genetic control of
embryogenesis in vitro. Lange et al. (1995) found that the
morphogenetic potential of callus tissues depends on the interaction
among a large number of genes with major and minor effects.
However, there are very few data on the influence exerted by individual genes on wheat somatic embryogenesis (Omelianchuk 1992).
These problems are conveniently handled by the use of genetic
systems with a known functional linkage between gene expression and
gene phenotypic manifestation. One of the best candidate systems is
that of reduced- height (Rht) genes, particularly because the
association of Rht genes with embryogenesis was noted earlier
for a culture of immature wheat embryos (Mathias and Atkinson 1988;
Djachouk et al. 2000; Lobachev 2000).