CYTOGENTICAL STUDIES ON THE BACKCROSSED PLANTS BETWEEN F1 HYBRIDS (T. Timopheevi×T. vugare) AND THEER PARENTS
1954 Volume 29 Issue 5-6 Pages 215-222
Details
1954 Volume 29 Issue 5-6 Pages 215-222
By backcrossing to the F1s of (Triticum Timopheevi×T. vulgare) with their parents, 24 BF1 plants were obtained, of which 21 plants were raised by the pollen of T. vulgare. And our cytological observations were carried out principally on them.
Consequently it ws found that these 21 BF1 plants were consisted of the plants having 2n=37 (1 plant), 2n=38 (4 plants), 2n=39 (7 plants), 2n=40 (4 plants), 2n=41 (4 plants) and 2n=42 (1 plant) respectively, the mode of 2n chromosome number being in 39. From this, it can be infered that of the gametes formed in F1 plants, these having 18 chromosomes play best their function as female.
Moreover, the behaviour of chromosomes at MI of P.M.Cs. was observed somewhat in detail on the 7 plants with different chromosome numbers, of which 1 plant having 2n=30 chromosomes was the one backcrossed by Timopheevi (see Table 2 and 3).
As a result of these observations, it became evident that by backcrossing the numbers of univalents and multivalents in BF1 plants decreased considerably, but the numbers of bivalents, especially of closed bivalents increased in comparison with those in F1s, and therefore the fertility of BF1 plants was raised strikingly.
