Cucurbit Genetics Cooperative Report 7:51-53 (article 23) 1984
Pitrat, M.
I.N.R.A., Centre de Recherches Agronomiques d’Avignon, B.P. 94, 84140 Montfavet, France
Until now only 4 gene linkages have been described in muskmelon: (1) bush (b) and yellow virescent (yv) – recombination 19.4% (5); (2) virus aphid transmission resistance (Vat) and Flaccida necrosis (Fn) – recombination 11.6%; (3) red stem (r) and male sterile-1 (ms-1) – recombination 25.6% (1); and (4) Zucchini yellow mosaic virus resistance (Zym) and andromonoecious (a) – recombination 13.1% (3).
A program was begun to find linkage relationships between the following genes:
- Fusarium oxysporum f. sp. melonis resistance: Fom-1 (resistance to pathotypes 0 and 2) in ‘Doublon’ and Fom-2 (resistance to pathotypes 0 and 1) in PI 414723 (supplied by G.W. Bohn).
- Watermelon mosaic virus-1 resistance (Wmv) in PI 414723.
- Necrotic spot virus resistance (nsv) to muskmelon necrotic spot virus in VA 435 supplied by Virginia Truck Expt. Sta.
- Zucchini yellow mosaic virus resistance (Zym) in PI 414723.
- Virus aphid transmission resistance (Vat) in PI 414723 or PI 161375.
- Powdery mildew resistance-X (Pm-X) resistance to Sphaerotheca fuliginea race 2 in PI 414723 (exact powdery mildew resistance gene is under study).
- glabrous (gl) in Arizona gl B supplied by R.E. Foster.
- yellow green (yg) in Arizona gl B.
- red stem (r) in 30569 supplied by J. D. McCreight.
- bush (b) in ‘Topmark Bush’ supplied by F. W. Zink.
F2 data from 4 of 19 gene combinations among these 10 genes studied to date strongly indicated linkage. The recombination fractions for these 4 gene pairs were calculated using the maximum likelihood method (Table 1). F2 data indicated independent assortment between the other 15 gene pairs (Table 2).
Table 1. Linkage between 4 gene pairs in muskmelon.
| Genes | Phasez | Number of plants observed in the expected dihybrid ratio | Chi square | Recombination | |||||
|---|---|---|---|---|---|---|---|---|---|
| 9 | 3 | 3 | 1 | Value | Standard error | ||||
| Fom-1 | Wmv | R | 104 | 52 | 44 | 0 | 19.876 | 0.0 | 7.07 |
| Fom-2 | yg | R | 161 | 10 | 17 | 53 | 145.309 | 11.4 | 6.34 |
| Zym | Pm-X | C | 110 | 47 | 40 | 0 | 15.314 | 0.0 | 7.12 |
| r | gl | R | 367 | 106 | 128 | 8 | 27.745 | 30.9 | 3.61 |
| zC=coupling; R=repulsion. | |||||||||
Table 2. Independent assortment between 15 gene pairs in muskmelon.
| Genes | Phasez | Number of plants observed in the expected dihybrid ratio | Chi square | ||||
|---|---|---|---|---|---|---|---|
| 9 | 3 | 3 | 1 | ||||
| Fom-1 | gl | R | 159 | 61 | 51 | 19 | 1.163 |
| Wmv | g | R | 113 | 31 | 36 | 13 | 0.999 |
| Vat | Zym | C | 107 | 36 | 29 | 17 | 3.461 |
| Wmv | nsv | R | 111 | 32 | 45 | 12 | 2.347 |
| gl | yg | C | 1177 | 394 | 377 | 141 | 1.402 |
| yg | b | R | 138 | 41 | 49 | 19 | 1.594 |
| yg | nsv | R | 167 | 62 | 56 | 19 | 0.550 |
| Pm-X | gl | R | 151 | 54 | 44 | 7 | 6.486 |
| Zym | nsv | R | 96 | 40 | 35 | 18 | 4.834 |
| Vat | b | R | 100 | 38 | 32 | 11 | 0.638 |
| Vat | nsv | R | 105 | 48 | 32 | 14 | 4.444 |
| b | gl | R | 141 | 47 | 46 | 13 | 0.428 |
| b | r | R | 108 | 31 | 31 | 9 | 1.350 |
| gl | nsv | R | 178 | 50 | 50 | 24 | 3.330 |
| Zym | b | R | 83 | 25 | 23 | 12 | 1.796 |
| zC=coupling; R=repulsion. | |||||||
Vat was already found independent from Fom-1, Fom-2 and ms-1 (2), Zym independent from Fom-1 and Fom-2 (3) and Fom-l independent from Fom-2 (4). The muskmelon linkage groups may tentatively be summarized from these and published data:
- Linkage group 1 : b – yv
- Linkage group 2 : Vat – Fn
- Linkage group 3 : ms-1 – r – gl
- Linkage group 4 : Zym – a – Pm-X
- Linkage group 5 : Fom-l – Wmv
- Linkage group 6 : Fom-2 – yg.
Gene nsv is independent from linkage groups 2 to 6. Its independence with group 1 is under study. The order in groups 3 and 4 is still unknown.
Literature Cited
- McCreight, J.D. 1983. Linkage of red stem and male sterile-1 in muskmelon. Cucurbit Genetics Coop. Rept. 6:48.
- Pitrat, M. and H. Lecoq. 1982. Relations genetiques entre les resistances par non-acceptation et par antibiose du melon a Aphis gossypii. Recherches de liaisons avec d’autres genes. Agronomie 2:503-508.
- Pitrat, M. and H. Lecoq. 1984. Inheritance of zucchini yellow mosaic virus resistance in Cucumis melo L. Euphytica 33 (in press).
- Risser, G. 1973. Etude de l’heredite de la resistance du melon (Cucumis melo) aux races 1 et 2 de Fusariuma oxysporum f. sp. melonis. Ann. Amelior. Plantes 23:259-263.
- Zink, F.W. 1977. Linkage of virescent foliage and plant growth habit in muskmelon. J. Amer. Soc. Hort. Sci. 102:613-615.