I crossed triticale (FEMALE) and wheat (male) for intriogressing some rye genes into wheat. The F1 generation is expected to be completely homogenous and heterozygous but the observations were not as expected. what could be the possible reasons?
@ I think trirticale is hexaploid and octoploid. Similarly wheat is diploid, tetraploid and hexaploid. What type of triticale and wheat you have crossed for introgression and what you have observed? Please write the detail.
If hexaploid wheat x triticale, there is most probably substitution between D/R chromosome, no recombination. Try to identify
for crossing between wheat and rye to get triticale
their is 2 types of triticales
1- wheat 4X cross (14 (1n) chromosome) with x rye (7 (1n) chromosome)=hexaploid triticale (6X)
2- 1- wheat 6X cross (21 (1n) chromosome) with x rye (7 (1n) chromosome)= octoploid triticale (8X)
if you crossed triticale (FEMALE) and wheat (male) for retrogression some rye genes into wheat. The F1 generation is expected to have some genotypes completely homogeneous, some heterogeneous in the rye genome means have from 1 up to 7 chromosomes and this will be not completely fertile genotypes as the rye genome will be single copy in the meta-phase during meiosis division.
Could have some problems with these cross: chromosome laggards, pollen viability, etc.
I´ve tried the cross between wheat and triticale, to put scab resistance in triticale, and the F1 was ok. It is important use the parents with the same number of chromosomes.
Genes that determinate morphology of triticale in general are located on the rye chromosomes 5R and 4/7R. If these chromosomes are present, the plant resembles according morphological traits to a typical triticale. The absence of one or both of them causes that plants are more or less of a wheat type. However, R/D substitutions are reducing a proportion of rye germ-plasm present in the triticale, thus working against the original philosophy that it has to combine desirable traits of wheat and rye. Therefore, Krolow (1973) proposed a model by which D genome chromosomes from 6x wheat could be introgressed in 6x triticale allowing R genome of rye to be a complete one. It refers to the crossing of 8x with 4x triticale and the selection on a 6x level. So, heterogenous plants in croses of 6x triticale with 6x wheat are probably result of R/D substitutions!!!
Thanks to you all.
I used hexaploid wheat as female parent and hexaploid triticale as pollinator. how will the D and R chromosomes behave?
- Badges
- Science topic
- Similar topics
- Agricultural Science
- Horticulture