The 2011 ASHS Annual Conference

The study was carried out to improve the fruit-set rate of water melon by treating LED which has the effect of sunshine improvement in low temperature period(Feb. ~ May month) causing amount of sunshine deficiency. According to the light quality(660nm, 450nm, 660nm:450nm=7:3) and light amount of LED, the differences of male and female-flower characters, fruit character and fruit-set rate were estimated. The some differences of morphological characters were observed by the different light quality. The morphological differences were not observed in the light amount of LED. In estimation of male and female-flower morphological characters, the male and female-flower weight, the ovary length, the ovary width, the petal length and the petal width were increased compared to the Control. The  female-flower weight(4.3), the ovary length(21.2) and the ovary width(14.9) were increased in 450nm wavelength compared to the LED treatments. The male-flower weight(0.7) and the petal length(20) were increased in 660nm wavelength compared. The petal width was increased in 450nm wavelength. The fruit-set rate and fruit character were increased in all LED treatments compared to the Control. The increment of fruit-set rate(70) was observed in 450nm wavelength compared to the LED treatments. The fruit length(65.2)  and the fruit width(48.9) were increased in 660nm wavelength. Accordingly, the 450nm wavelength has an effect on improving fruit-set rate, the 660nm wavelength on increasing fruit size in low temperature period(Feb. ~ May month). Also, we expect that the LED treatment are increasing the amount of photosynthesis which is improving the quality of water melon.