0023-6152

AA00697606

4674

査読無

0023-6152

AA00697606

To improve the fruit quality in triploid grapes, the mechanism underlying formation of unfertilized small seeds with hard seeds coat was investigated in berries of a large number of triploid hybrits obtained from reciprocal crosses between diploid 'Muscat Bailey A' and tetraploid 'Red Pearl' In each triploid hybrid plant, ten flower clusters trimmed so that they have about 200 flowes each were open-pollinated, and other ten flower clusters trimmed similary were immersed in a solution of GA3 (100mg/l) at the full bloom stage. Triploid hybrid plants that produced unfertilized small seeds were8/18 plants for open-pollinated clusters and 21/68 plants for GA3-treated clusters. The rate of unfertilized small seeds was different ni different triploid hybrids, and the rates in each triploid plant showed small variation between twoo or three years examined. In GA3-treated clusters, the rate of small hard seeds in each hybrid was dramatically decreased. These results indicated that the extent of unfertilized small seed formation is a triploid-plant-specific character and that the formation is highly suppressed by immersion teratment of the flower clusters with high concentration of GA3 solution.