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Tetraploid rye was crossed with different tetraploid triticale lines. The F₁ generation of tetraploid rye × tetraploid triticale hybrids was backcrossed with 4x rye. After backcrossing, all BC₁-F₁ plants were subjected to open pollination, whereas in the BC₁-F₂ generations only plants with wheat chromosomes in their karyotypes were open-pollinated. Substitution, addition and addition-substitution lines of wheat chromosomes in tetraploid rye were isolated from the F₂ and F₃ of BC₁. In 60 plants of BC₁-F₂, 59 chromosomes from the A genome and 9 from the B genome of wheat were recovered. The wheat chromosomes were monosomic except for five plants which were disomic, viz. 1A and 5A in two plants each, and a translocated 3AS/5AL in one plant. In 235 BC₁-F₃ plants, 174 wheat addition and substitution chromosomes were found, 143 from the A genome and 31 from the B genome. All wheat chromosomes except 3A from the A genome and four chromosomes from the B genome - 2B, 3B, 5B and 7B were recovered. The number of substitutions ranged from one to four per plant, only two plants having four. In the group of addition plants the number of added wheat chromosomes ranged from one to two, and in the case of addition-substitution plants — from two to four. Wheat chromosomes occurred in monosomic form, except 10 plants. Six substitution plants were disomic for 1 A, 2A, 5A, 7A, 2B and 3B, respectively. One was disomic for 1A and 5A in two addition plants. Two addition-substitution plants were double disomic: 1A and 5A - in one, and 1A and 3B in the other. In the BC₁-F₃ generation, 23 different translocations were found, four of which occurred between wheat chromosomes and the remaining 19 - between wheat and rye chromosomes. Translocated chromosomes were monosomic, except four plants. Two of them were disomic for 3AS/4RL, one for 4AS/4RS and one for 7AS/7RS. The fertility of both addition and substitution plants ranged from 0 to 38.0 seeds/spike, regardless of the chromosome number, with a mean of 9.61 seeds/spike. Plants with 28 chromosomes showed singnificantly higher fertility than plants with 29 and more chromosomes, except additoion plants with chromosomes 5A and 5B. The analysis of the influence of particular wheat chromosomes on plant fertility showed that both substitution and addition plants with chromosome 6A had the highest average fertility, while plants with chromosome 2B in substitution lines as well as plants with chromosome 2A in addition and addition-substitution lines had the lowest fertility.
The valuable genes of Aegilops biuncialis, Ae. ovala, Ae. kotschyi, and Ae. variabilis were transferred to rye, by crossing Aegilops-rye amphiploids with tetraploid and diploid substitution rye. The C-banded karyotype of the BC₁ and BC₂ generations of amphiploids with 4x substitution rye and BC₁ with 2x substitution rye showed great variation in chromosome number and composition. In the BC₁ generation of amphiploids with 4x and 2x substitution rye, seed set success rate and germination rate varied depending on origin. However, plant sterility in all cross combinations of amphiploids with 4x and 2x substitution rye resulted in their elimination from further experiments in the BC₃ and BC₂ generations, respectively. In backcrosses of 4x substitution rye with amphiploids Ae. variabilis x rye 4x, fertile 4x rye plants containing Aegilops chromatin were produced in the BC₂ generation.
Chromosome identification using fluorescence in situ hybridization (FISH) is widely used in cytogenetic research. It is a diagnostic tool helpful in chromosome identification. It can also be used to characterize alien introgressions, when exercised in a combination with genomic in situ hybridization (GISH). This work aims to find chromosome identification of Aegilops species and Aegilops × Secale amphiploids, which can be used in cereal breeding as a source of favourable agronomic traits. Four diploid and two tetraploid Aegilops species and three Aegilops × Secale hybrids were analysed using FISH with pSc119.2, pAs1, 5S rDNA and 25S rDNA clones to differentiate the U-, M-, Sshand D-subgenome chromosomes of Aegilops genus. Additionally, GISH for chromosome categorization was carried out. Differences in the hybridization patterns allowed to identify all U-, M-, Ssh- and D-subgenome chromosomes. Some differences in localization of the rDNA, pSc119.2 and pAs1 sequences between analogue subgenomes in diploid and tetraploid species and Aegilops × Secale hybrids were detected. The hybridization pattern of the M and S genome was more variable than that of the U and D genome. An importance of the cytogenetic markers in plant breeding and their possible role in chromosome structure, function and evolution is discussed.
Wykonano analizy cytologiczne kariotypów karłowych mutantów pszenżyta ozimego oraz ich form wyjściowych (kontrola) metodą C - prążkową, a także analizy białek zapasowych (glutenin wysokocząsteczkowych) metodą rozdziału elektroforetycznego na żelu poliakrymidowym z dodatkiem soli sodowej siarczanu dodecylu (SDS PAGE). Analizy cytologiczne wykazały, że wszystkie badane materiały miały pełny zestaw chromosomów heksaploidalnego pszenżyta. Wzór prążkowy chromosomów kontroli - 2088 i 51/59 zasadniczo nie różnił się od standardu. Jednakże w kontroli zaobserwowano różnice w strukturze chromosomów 1R i 4A. W karłowych mutantach zróżnicowane były chromosomy 1R, 3R oraz 4R. Niektóre obserwowane zmiany w strukturze rozmieszczenia prążków mogą świadczyć o delecji, translokacji i/lub duplikacji fragmentów ramion chromosomów. Badane mutanty, a także ich formy wyjściowe (kontrola) różniły się również pod względem składu podjednostek wysokocząsteczkowych glutenin. Mutanty linii 2088 - Tm 942, Tm 917 i Tm 1294 - były polimorficzne, natomiast mutanty rodu 51/59 - Tm 1297, Tm 1300 i Tm 1303 były identyczne i całkowicie różniły się od kontroli. Także kontrola 2088 różniła się od kontroli 51/59.
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