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Pisum Genetics |
Volume 23 |
1991 |
Research Reports |
pages 35-37 |
K219, an early flowering pea mutant with neutral reaction to photoperiod
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Sidorova, K.K. and L.P. Uzhintseva
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Inst. of Cytology and Genetics Siberian Branch of USSR Acad. of Sciences Novosibirsk 630090, Russia |
The early flowering mutants K218 and K219 were induced in the variety Torsdag using EMS and the two mutants shown to be monogenic recessive and non-allelic (6). Additional data illustrating their monogenic recessive nature is provided in Table 1. K218 was characterised in several earlier studies and found to have a day neutral habit (2, 3, 5). The symbol dne was assigned (3) when the mutant proved to be non-allelic with sn, the first gene shown to confer a day neutral flowering habit (1). In Tables 2 and 3 we provide data illustrating the behaviour and characteristics of mutant K219. The data clearly show the early flowering, day neutral habit of K219 and that it has characteristics similar to K218 and typical also of early flowering day neutral lines with genotype sn (e.g. see 4). However, in the absence of the necessary allelism test, we cannot say whether K219 is allelic with sn or whether it is a new flowering gene.
Table 1. F2 segregation data for reciprocal crosses between the initial variety Torsdag and mutants K218 and K219. F1 plants had the same phenotype as Torsdag.
|
Cross |
Phenotype |
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|
Progenitor |
Mutant |
Total |
c2 |
|
|
K218 x Torsdag |
69 |
19 |
88 |
0.55 |
|
Torsdag x K218 |
69 |
20 |
89 |
0.30 |
|
Total |
138 |
39 |
177 |
0.83 |
|
K219 x Torsdag |
82 |
31 |
113 |
0.36 |
|
Torsdag x K219 |
93 |
25 |
118 |
0.92 |
|
Total |
175 |
56 |
231 |
0.07 |
Table 2. The effect of photoperiod on the duration of various developmental stages in the initial variety Torsdag and mutants K218 and K219.
|
Line |
Photoperiod* |
Node of first flower formation |
Number of days |
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|
Seedlings to budding |
Seedlings to flowering |
Seedlings to beginning of ripening |
Seedlings to maturity |
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|
Torsdag |
LD |
14-15 |
26 |
33 |
59 |
73 |
|
|
SD |
22-24 |
42 |
46 |
72 |
91 |
|
K218 |
LD |
12-13 |
21 |
30 |
56 |
71 |
|
|
SD |
12-13 |
22 |
31 |
60 |
74 |
|
K219 |
LD |
10-11 |
18 |
26 |
52 |
68 |
|
|
SD |
10-11 |
19 |
26 |
49 |
68 |
* LD = natural summer long day photoperiod at Novosibirsk (17-18 h).
SD = 8h light per day.
Table 3. Means ± SE for several traits in the initial variety Torsdag and mutants K218 and K219 under short and long day conditions.
|
Line |
Photoperiod* |
Plant height (cm) |
Node of first flower formation |
Number of pods |
Number of seeds |
Weight of seeds (g) |
|
Torsdag |
LD |
187.1 ± 2.9 |
14.7 ± 0.2 |
12.7 ± 0.4 |
29.8 ± 1.1 |
8.5 ± 0.3 |
|
|
SD |
215.1 ± 2.9 |
22.4 ± 0.3 |
13.3 ± 0.8 |
23.5 ± 1.6 |
6.6 ± 0.6 |
|
K218 |
LD |
157.1 ± 2.1 |
12.1 ± 0.2 |
9.2 ± 0.5 |
24.4 ± 1.6 |
6.3 ± 0.4 |
|
|
SD |
140.5 ± 2.3 |
12.6 ± 0.2 |
9.5 ± 0.6 |
20.0 ± 1.3 |
5.2 ± 0.3 |
|
K219 |
LD |
161.3 ± 1.6 |
10.7 ± 0.1 |
11.5 ± 0.4 |
26.1 ± 0.7 |
7.0 ± 0.2 |
|
|
SD |
131.6 ± 1.9 |
10.6 ± 0.1 |
8.7 ± 0.4 |
17.2 ± 1.0 |
4.4 ± 0.3 |
* LD = natural summer long day photoperiod at Novosibirsk (17-18 h).
SD = 8h light per day.
Pea mutants with a neutral reaction to photoperiod are valuable as initial material in breeding for early maturing pods. There is a possibility to use such mutants in breeding new genotypes of pea with a characteristic complex of valuable traits. Crossing photoperiodically neutral mutants with non-shattering forms resulted in strains exhibiting resistance to seed shattering, an early pod maturation and high productivity.
Barber, H.N. 1959. Heredity 13:33-60.
King, W.M. and Murfet, I.C. 1985. Ann. Bot. 56:835-846.
Murfet,
I.C. 1982. In Documentation of Genetic Resources: A Model, Eds
S. Blixt and J.J. Williams, IBPGR, Rome, pp 45-51.
Murfet, I.C. and Ezhova, T.A. 1991. Pisum Genetics 23:19-25.
Sidorova, K.K. and Uzhintseva, L.P. 1977. PNL 9:51.
Uzhintseva, L.P. and Sidorova, K.K. 1979. Genetika 15:1076-1082.