Pisum Genetics 

Volume 23

1991

Research Reports

pages 35-37

K219, an early flowering pea mutant with neutral reaction to photoperiod

Sidorova, K.K. and

L.P. Uzhintseva

 

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

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

Seedlings to budding

Seedlings to flowering

Seedlings to beginning of ripening

Seedlings to maturity

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.

  1. Barber, H.N. 1959. Heredity 13:33-60.

  2. King, W.M. and Murfet, I.C. 1985. Ann. Bot. 56:835-846.

  3. Murfet, I.C. 1982. In Documentation of Genetic Resources: A Model, Eds
    S. Blixt and J.J. Williams, IBPGR, Rome, pp 45-51.

  4. Murfet, I.C. and Ezhova, T.A. 1991. Pisum Genetics 23:19-25.

  5. Sidorova, K.K. and Uzhintseva, L.P. 1977. PNL 9:51.

  6. Uzhintseva, L.P. and Sidorova, K.K. 1979. Genetika 15:1076-1082.