Kenji Kawase

CHANGES IN CARBOHYDRATE AND WATER CONTENT WITH OVULE GROWTH OF GINKGO BILOBA L.

SummaryThe carbohydrate and water contents of the ovule of Ginkgo biloba L. (ginkgo) were evaluated during its development. The ovule grew rapidly (stage I) after pollination in early May, temporarily stopped growing, in mid-July (stage II), and resumed growth slowly (stage III) from mid-August until maturation. The water content in the endosperm and outer integument were highest in June, and decreased thereafter, accompanied by ovule development. In the endosperm, the sugar content decreased rapidly during stage I, followed by a rapid increase in the starch content which is high level in early September. In the outer integument, the sugar content increased in early June, and remained nearly constant until early August. Then it transiently decreased in mid-August, when meso-integument hardening was completed, followed by a rapid increase. The starch content in the outer integument was low, but peaked in mid-August, when the sugar content was lowest. Although ginkgo nuts are usually harvested in October, w...

JASMONIC ACID EFFECTS ON GIBBERELLIC ACID-INDUCED SEEDLESSNESS IN 'NEO MUSCAT' TABLE GRAPES

SummaryThe effect of jasmonic acid (JA), applied alone or in combination with gibberellin A3 (GA3), on the induction of seedlessness in ‘Neo Muscat’ (Vitis vinifera) was investigated. Endogenous JA levels in the florets of ‘Neo Muscat’ and ‘Delaware’ (Vitis vinifera x Vitis labrusca) were also studied. The proportion of seedless berries induced by application of GA3 alone 12 d before full bloom (DBB) was 17.0%, and at 6 DBB it was 62.7%. The proportion of seedless berries induced by GA3 + JA applied 6 DBB increased significantly with increasing JA concentration, while pollen germination decreased quadratically with increasing JA concentration. JA did not affect seed number per berry or the seed’s fresh weight. Treatment with JA alone also induced seedlessness effectively. Although the fresh weight of the seedless berries induced by the application of GA3 + JA 12 DBB decreased quadratically with increasing JA concentration, there were no significant differences between the treatments at 6 DBB. Fruit solubl...