Czech Journal of Genetics and Plant Breeding, 2005 (vol. 41), issue 1

Two Mutants Affecting Adaptative Responses to Abiotic Stresses in Barley Seedlings

A E. Martínez, A Landau, P T. García, G Polenta, M C. Arias, R Murray, N Pensel, A R. Prina

Czech J. Genet. Plant Breed., 2005, 41(1):1-10 | DOI: 10.17221/3675-CJGPB

Two novel mutants which affect the adaptative responses of barley seedlings to different abiotic stresses are described. They allow us to explore some aspects of adaptative phenomena that are little known in higher plants. One of these mutants corresponds to a nuclear gene which under certain circumstances in the wild type barley induces additional ethylene production in the seedling roots. This mechanism seems to be involved in inducing a negative hydrotropic growth of the roots, a phenomenon that we interpret as a response avoiding waterlogging. The other mutant corresponds to a plastid encoded gene which is involved in photosystem I and II stability...

Relationships Between Some Hordein Components and Quality Properties in Two Tunisian Barley Varieties as Influenced by Nitrogen Fertilisation

L Bettaieb-Ben Kaab, M El Felah, M Lauriere

Czech J. Genet. Plant Breed., 2005, 41(1):11-16 | DOI: 10.17221/3676-CJGPB

Two Tunisian barley varieties, Martin and Rihane, differing by their degrees of adaptation to the environmental conditions and grain yield potential, were grown under different levels of nitrogen (N) fertilisation. The effect of nitrogen supply on the hordein components (expressed in mg per albumen) was determined by Nu-PAGE electrophoresis system using the MOBS running buffer and densitometric analysis. Increasing nitrogen fertilisation increased the protein content by increasing the amount of C-hordeins. The sub-fraction BIII of high molecular weight B-hordeins appeared, in the present study, as the best criterion for distinguishing between the two...

Structural Variability of Subtelomeres Applied for Genotyping of Selected Potato Varieties

K Neplechová, E Sýkorová, M Novotná, J Ptáček, J Fajkus

Czech J. Genet. Plant Breed., 2005, 41(1):17-22 | DOI: 10.17221/3677-CJGPB

Subtelomeric regions reveal a relatively high degree of polymorphism due to the increased frequency of recombination events in these chromosome loci. In a search for molecular markers applicable to genotyping of potato varieties, we focused on two possible sources of polymorphism occurring in this region: (i) arrangement of blocks of subtelomeric chromatin; (ii) structure of telomere-subtelomere boundary. Analysis of the internal arrangement of subtelomeric sequences showed several types of cultivar-specific spectra of PCR products arising from the variant orientation of sequence units of the ST3-subtelomeric sequence, or from different...

Combining Ability Analysis of Heat Tolerance in Gossypium hirsutum L.

M T Azhar, A A Khan, I A Khan

Czech J. Genet. Plant Breed., 2005, 41(1):23-28 | DOI: 10.17221/3678-CJGPB

In order to study the genetic control of heat tolerance, four varieties/lines of Gossypium hirsutum L., namely MNH-554, Cocker-304, Delcerro and Albacala (71) 1190, were crossed in all possible combinations. Heat tolerance of 12 hybrids and their parents was measured at reproductive phase using an electrolyte leakage technique. The genetic analysis of the data showed significant effects of specific combining ability and reciprocals, but the effect of general combining ability appeared to be non-significant. Comparison of the parents for heat tolerance revealed that Delcerro and MNH-554 were the best general combiners for the character. The...