Abstract
This paper reports the study on the effects of daylength and light intensity on the growth of seedlings and the flower formation in egg-plant.
Egg-plant seedlings were grown under 4-, 8-, 12- and 15-16-hr in the first experiment, and under 6-, 8-, 10-, 12- and 14.5-15.5-hr day-lengths in the second experiment. The seedlings were exposed to high light intensity of natural daylight in all the daylengths.
The longer the day-length, the more vigorous the growth of seedlings and the earlier the date of flower bud differentiation, resulting in the decrease in the number of leaves to the first flower, and in the increase in the number of flowers.
The seedlings were grown unde 4-, 8-, 12-, 16-, 20and 24-hr in the third experiment, and under 8-, 16and 24-hr day-length in the fourth experiment. The day-lengths longer than 8 hr were supplemented by low intensity lighting of incandescent lamps.
The longer the day-length up to 8-12 hr, the more vigorous the growth of seedlings, being followed with the earlier flower bud differentiation with the decrease in the number of leaves to the first flower. The daylength longer than 8-12 hr, on the other hand, induced the more vigorous growth of seedlings, but did not affect the flower formation.
The seedlings were exposed to the natural daylight for 8 hr f rom 6 : 00 a.m. to 2: 00p.m., from 8: 00a.m. to 4: 00p.m. and 10: 00 a.m. to 6: 00p.m. daily, respectively.
Delayed exposure to the daylight restricted the growth of seedlings and retarded the flower bud differentiation, resulting in the increase in the number of leaves to the first flower and in the decrease of number of flowers.
The seedlings were grown at four different light intensities (100, 75, 50 and 25 per cent of natural day light), and three different light intensities (100, 60 and 20 per cent of natural day light) .
The higher the light intensity, the more vigorous the growth of seedlings, being followed with the earlier flower bud differentiation with the decrease in the number of leaves to the first flower, and the increased number of flowers.
