Effects Of Supplemental Light On Tomato Seedlings And Lettucegrowth And Development, Yield And Quality

At present,most of the researches had focused on the LED as the main light source for light quality ratio,which was applied during the entire growth cycle of vegetables.There was no much reaserches of the LED light as a supplemental light source on the growth and development under different light qualities and supplemental light period.In this study,the effects of supplemental red and blue light in different growth stages on the growth and development of lettuce were studied.The effects of supplemental blue light during different period in one day on the yield of lettuce were conducted.And the effects of far-red light supplemented in daytime and red light in night on the growth of tomato seedlings were studied.The aim was to provide more basis for the cultivation of vegetables in artificial light environment.The main conclusions are as follows:(1)In the growth period A,the effects of supplemental light on the growth of lettuce was greater than supplemental light during B period.The increase of dry matter in FLBR treatment was significantly increased by 27.3% compared with the control.The leaf area of FLRR and FLRB which were supplemented with red light in A period were 22.7% and 17.3%.significant higher than that of control.The content of vitamin C in FLBB treatment and CK2 treatment which under the light treatments include high blue light account during total growth stages were 15.3% and 13.6% significantly increased by compared with FLBR treatment.Supplemental blue or red light in FLRR,FLRB,FLBR and FLBB treatments were 34.3%,50.8%,37.3% and 32.6%significantly reduced compared to the control,respectively.(2)Spplemental blue light 1 hour before turning on the lights is the most conducive treatment to the accumulation of lettuce production.Fresh weight,dry weight,leaf area and leaf number in the light 1 hour before the blue light treatment significantly improved 103.75%,68.9 %,84.69%,39.51% compared with the control.(3)Compared with the control,supplemental far-red light in day time significantly increased the plant height of tomato seedlings by 27.6%,but significantly reduced stems thick by 15.1%.The number of leaves of tomato seedlings decreased from 8.53 to 6.57.Flowering time was in advanced.Compared with the control,supplemental red light in night significantly decreased the plant height by 13.7%,but significantly increased the stem diameter by 29.1%.The number of flowering leaves of tomato seedlings increased from 8.53 to 11.26,the flowering time was delayed and increased the seedling index.(4)In summary,supplemental light played an important role on the vegetable yield,quality and growth and development.The time and light quality of supplemental light qualities had different effects on lettuce and tomato seedlings.In actual production,the supplemetal light source can be applied according to production requirements to improve the vegetable yield,regulate morphology of lettuce,and increase the nutrient quality.