PNL Volume 21 1989 RESEARCH REPORTS                    73
A NEW GENE CRISPOID (crd) ON CHROMOSOME 1
Swiecicki, W. K.                                                Plant Breeding Station, Wiatrowo
62100 Wagrowiec, Poland
In experiments on induced mutations (1) a mutant of crispoid type was selected after seed treatment of line Wt 3527 by 0.014% NEU and included in the Wiatrowo pea gene bank in 1981 under catalogue number Wt 11300. Crispoid pea plants are characterized by a bigger and more waved leaf surface than normal and the stipules are toothed at the base (Fig. 1). Some connection with the cerosa and wilty phenotypes could also be seen. Locus identity tests for crispoid (Wt 11300) with crispa (Wt 11297, cri), crispi folius fertilis (Wt 16118, crif) and curled (Wt 15855, curl) showed that all of these phenotypes are controlled by different loci. A good monohybrid segregtion was obtained in the F2 population of cross Wt 3527 x Wt 11300 (153 normal: 48 mutant plants; X2 = 0.13). Therefore the symbol crd for crispoid is suggested.
To locate the new gene, several crosses were made with tester lines. Monogenic recessive inheritance of crd was confirmed in these F2 populations (e.g. Table 1A) . Linkage between crd and the a locus was found in the F2 of crosses Wt 11300 x Wt 11288 (recomb. fract. 21.2) and Wt 11300 x Wt 11238 (recomb. fract. 20.4, Table IB). The latter cross also revealed tight linkage between crd and the isozyme locus Aat-p (recomb. fract. 2.3) but the recombination fraction of 35.7 ± 8.7 for crd and the d locus does not differ significatnly from that expected with free recombination (Table IB). These results suggest that crd is located on chromosome 1 close to Aat-p, probably between Aat-p and Est-3 (2). The latter locus should be utilised in more detailed mapping studies. The following linkage map is tentatively suggested.
I acknowledge the help of Dr. Bogdan Wolko in separating genotypes or the Aat-p locus.
1. Swiecicki, W. K. 1984. PNL 16:84-86.
2. Weeden, N. F. 1985. In: The Pea Crop. A Basis for Improvement. Eds. P. D. Hebblethwaite, M. C. Heath, and T. C. K. Dawkins, Butterworths, London, pp. 55-66.
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PNL Volume 21            1989         RESEARCH REPORTS
Table 1. Phenotypic distribution in an F2 population from a cross between Wt 11300 (crispoid) and Wt 11238 (testerline).
A. Monohybrid F2 segregation
Phenotype
Total
Chi-square (3:1)
A
98
D
71
Aat-p
92
Crd
91
a
26
d
27
aat-p
32
crd
33
124
98
124
124
1 .08 0.34 0.04 0.17
B. Joint segregation of Crd with A, D and Aat-p
Phenotype
Total
Joint Chi-square
Recomb. fract.
S.E.
Phase
A Crd
88
A Aat-p
84
A D
71
D Crd
58
D Aat-p
59
Crd Aat-p
90
A crd
15
A aat-p
14
A d
27
D crd
13
D aat-p
12
Crd aat-p
1
a Crd
8
a Aat-p
8
a D
1
d Crd
25
d Aat-p
25
crd Aat-p
2
a crd
18
a aat-p
18
a d
1
d crd
2
d aat-p
2
crd aat-p
31
124
124
98
98
98
124
30.0
30.2
1.0
1.6
1.6
102.1
20.4 19.7 63.1
35.7
37.0
2.3
4.1 4.1 6.4 8.7 8.6 1.4
C C
R R R C
Fig. 1. The leaf of crispoid mutant Wt 11300 (left) and the initial line Wt 3527 (right).
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