Cucurbit Genetics Cooperative Report 10:78-79 (article 40) 1987
Menahem Edelstein, Haim Nerson, Harry S. Paris, Zvi Karchi and Yosef Burger
Department of Vegetable Crops, Agricultural Research Organization, Newe Ya’ar Experiment Station, P. 0. Haifa, Israel
Spaghetti squash (Cucurbita pepo) has experienced a surge of popularity during the past few years. Since its introduction into North America from Japan in 1936 (2), the sole cultivar has been ‘Vegetable Spaghetti’, a vine- type, open-pollinated, pale-fruited cultivar. We introduced for 1986 the first hybrid spaghetti squash cultivars, ‘Orangetti’ and ‘Go-Getti’ (1). Both hybrids are improved over ‘Vegetable Spaghetti’ by having semi-bush habit and attractive, intense fruit color.
As with many other commercial C. pepo hybrids, ‘Orangetti’ and ‘Go-Getti’ are produced by treatment of the female parent with ethephon and use of honeybees for transferring pollen from the male parent to the female. It was readily noticeable that ethephon treatment of squash resulted in smaller plants which in turn produced smaller fruits with seeds about one-third smaller than normal. Although germinability was excellent, no comparison had been made between plants developing from small seeds with plants developing from large seeds. The aim of the present work was to compare the vegetative development of plants developing from large and from small seeds.
Two experiments were conducted for this comparison, each with 2 treatments, “large” seeds (average seed weight 161 mg) and “small” seeds (average seed weight 108 mg). Seeds of both treatments were derived from a commercial stock of ‘Vegetable Spaghetti’ obtained from Sakata Seeds. The largest and smallest seeds from this commercial stock were selected for the treatments.
The first experiment was sown in a heated greenhouse on 16 October 1985 at Newe Ya’ar (Yizre’el Valley, northern Israel) in 5-liter plastic pots. The medium was grumusol-peat-vermiculite (1:1:1, v:v:v). There were 4 plants per treatment. The plants were taken 3 weeks after emergence for measurement of leaf blade fresh weight, stem and petiole fresh weight, and stem length.
The second experiment was sown in the field on raised beds, 2 m between bed centers and 2 plants every 50 cm in the row, on 3 April 1986 at Newe Ya’ar. There were 6 plants per treatment, which were taken from the center of a 24 m2 plot 40 days after emergence for measurement of the same variables as above and for counting the number of internodes.
The results, presented in Tables 1 and 2, show that in spaghetti squash early vegetative development is unaffected by seed size. Seeds produced following ethephon treatment can be expected to develop into plants of the same vegetative vigor as seeds produced without ethephon treatment.
Table 1. Influence of seed size on early vegetative development of spaghetti squash. Greenhouse, Autumn 1985.
| Seed size | Leaf blade fresh weight (g) |
Stem + petiole fresh weight (g) |
Stem length (cm) |
|---|---|---|---|
| Large | 9.58 | 9.67 | 27.6 |
| Small | 9.12 | 9.25 | 31.6 |
| t | 0.60 | 0.41 | 0.67 |
| P | >0.50 | >0.50 | >0.50 |
Table 2. Influence of seed size on early vegetative development of spaghetti squash. Field, Spring 1986.
| Seed size | Leaf blade fresh weight (g) |
Stem + petiole fresh weight (g) |
Stem Length (cm) |
Number of internodes |
|---|---|---|---|---|
| Large | 217.3 | 437.9 | 364.8 | 47.3 |
| Small | 254.9 | 409.2 | 392.3 | 53.7 |
| t | 0.33 | 0.27 | 0.10 | 0.24 |
| P | >0.50 | >0.50 | >0.50 | >0.50 |
Literature Cited
- Paris, H.S., M. Edelstein, H. Nerson, Y. Burger, Z. Karchi, and D. Lozner. 1985. ‘Orangetti’ and ‘Go-Getti’, two new spaghetti squash hybrids. Hassadeh 66: 254-256 (Hebrew, English abstract).
- Torrey, T.C. 1986. Written communication (to HSP). June 18.
Contribution No. 1902-E, 1986 series, from the Agricultural Research Organization, Bet Dagan, Israel.