Cucurbit Genetics Cooperative Report 13:45-46 (article 17) 1990
Xing-ping Zhang and Ming Wang
Department of Horticulture, Northwestern Agricultural University, Yangling, Shaanxi 712100, P.R. China
In 1983, Xitong Xia and his colleagues found two male-sterile watermelon plants with small, shrunken anthers and aborted pollen, from among selfed progeny of cv. Nongmi No. 100. They pollinated each male-sterile plant separately with pollen from two fertile sibs, which were also self-pollinated. The four F1 hybrids and progeny from the four fertile sibs were planted and scored for male fertility in 1984. Three of the four F1 hybrids segregated 1:1 (fertile:sterile), and the progeny of the self-pollinated fertile sibs segregated 3:1 (fertile:sterile). Testing and selections were make over three subsequent generations. A male-sterile line, G17AB, with a well-behaved single recessive gene, designated ms, was reported in 1986 (Chinese reference not cited). The ms gene has been introduced into two of their breeding lines.
The Chinese ms watermelon line, G17AB, came into our breeding program in 1988. In contrast to the gms trait described by Watts (4), the Chinese ms watermelon line contains no gross morphological differences between sterile and fertile plants. However, there are similarities in male flower morphology. Male flowers of a gms line (provided by B.B. Rhodes, Clemson University) and the Chinese ms line are both very small and usually do not open early in the season. When they do open later in the season, the pollen is shrunken and non-viable.
G17AB is a medium round melon with dark green stripes (similar to the striping in ‘Sugarlee’). Fruit matures about 100 days after sowing and 32 days after flowering. Under our conditions, G17AB fruit mature before ‘Sugarbaby’. Flesh is red, with small, dark brown seed. The number of seed per male-sterile fruit is nearly normal or slightly less than fruit on male fertile plants. The soluble solids content is about 10 per cent.
This ms line has been used as a maternal parent for F1 seed production in China. This system of F1 seed production was suggested by Rhodes and coworkers (1,2,3). In 1988, Rhodes (personal communication) suggested that a new male-sterile combination might be obtained by crossing lines containing the Chinese ms and the gms traits. These crosses are being made by Rhodes at Clemson University and Zhang at Northwestern Agricultural University. Through his collaborative research we hope to develop commercial watermelon lines with this new male-sterile combination.
Literature Cited
- Love, S. L., B. B. Rhodes and P. E. Nugent. 1986. Controlled pollination transfer of a nuclear male sterile gene from a diploid to a tetraploid watermelon line. Euphytica 35:636-638.
- Rhodes, B. B., B. A. Murdock and J. W. Adelberg. 1989. A second look at the glabrous male-sterile (gms) character in watermelon. Cucurbit Genetics Coop. Rpt. 12:58.
- Rhodes, B. B., J. W. Adelberg and R. T. Nagata. 1988. Efforts to use the gms gene to produce commercial seedless watermelons. International Symposium on Horticultural Germplasm, Cultivated and Wild (Abstract). 171.
- Watts, V. M. 1962. A marked male-sterile mutant in watermelon. Proc. Amer. Soc. Hort. Sci. 81:498-505.