We applied auxin, cytokinin, gibberellins, and gibberellin synthetic inhibitor to flowers of 'Ohrin', which is parthenocarpic, and 'Fuji', which is non-parthenocarpic, to elucidate the relationship between plant growth regulators and parthenocarpy in apple. The percentage of fruit set in gibberellin A 3 (GA 3 ) was about 60% in 'Ohrin' and about 7% in 'Fuji'. Forchlorfenuron (CPPU) combined with GA 3 treatment increased the fruit retention rate more than 14 days after treatment (DAT) than GA 3 alone. Dichlorprop (2,4-DP) combined with GA 3 slightly enhanced the gibberellin effect of inducing parthenocarpy. In 'Ohrin', GA 3 and gibberellin A 4 + 7 (GA 4 + 7 ) showed a higher fruit retention rate before flowering than after. Parthenocarpic fruits were induced even when uniconazole (UCZ) was sprayed after flowering, but not before flowering. The calyx end was large in GA 4 + 7 , and in GA 3 and CPPU singly, and GA 3 and CPPU combined treatments, which increased the percentage of fruit set. These results suggest that gibberellins before flowering trigger parthenocarpic apple fruits. Subsequent fruit growth requires cytokinins and auxin.

To elucidate the roles of plant growth regulators during fruit development in highbush blueberry (Vaccinium corymbosum L.), we investigated indole-3-acetic acid (IAA) and abscisic acid (ABA) concentrations, ethylene evolution in fruits during fruiting to ripening in 'Berkeley', and the ABA concentration and ethylene evolution at color stages of fruits in 'Earliblue', 'Berkeley', and 'Jersey'. The IAA concentration increased during seed enlargement. During the maturation stage, the change in the ABA concentration resembled that of ethylene evolution. Ethylene evolution peaked at the same or one color stage earlier than the ABA concentration. The ABA concentration increased simultaneously with ethylene evolution in 'Earliblue' and 'Berkeley', and the ABA concentration increased later than ethylene evolution in 'Jersey'. Furthermore, color stages with each of the ABA concentration and respiration rate peak, which is earlier, differed among cultivars. The relationship between ABA and anthocyanin concentrations seems to differ among cultivars. It was found that the ABA concentration changed simultaneously with fruit firmness as well as total soluble solid contents.

Foxtail millet, common millet and Japanese barnyard millet have traditionally been important food sources in East Asian countries. Although waxy types of foxtail and common millet have been identified, a waxy mutant of the allohexaploid crop Japanese barnyard millet has not yet been reported. However, several Japanese landraces have been identified that have approximately half the level of amylose found in other varieties. We employed one of the low amylose landraces, 'Noge-Hie', to produce waxy Japanese barnyard millet using a c-radiation treatment. The seeds from a single M 2 plant stained red-brown with iodine solution, indicating the starch in the seeds lacked amylose. Colorimetric tests indicated that amylose was not present in endosperm tissue of the mutant, and analysis of starch granule bound proteins showed that waxy (Wx) protein was absent from the starch granules. The waxy trait was stably inherited in subsequent generations. Additionally, a PCR-based analysis demonstrated the presence of three separate waxy genes in the millet, and indicated that the low amylose landraces carry a deletion in one of these three genes.

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