The Effect Of Different Light Quality LED Light Source Combination To The Tomato And Cucumber Seedlings

Vegetable seeding is an important part of the vegetable production,which is greatly affected by the environment.Raising seedlings under unsuitable environmental conditions will affect the quality of seedlings,and affect vegetable production.Therefore,intensification,specialization and commercialization are inevitable trend of development.With the increasing demand for the quantity,quality and efficiency of vegetable seedlings,the requirements for the control of environmental conditions in the process of vegetable seeding are becoming more strict.Industrial breeding has become the main mode in developed countries and regions of vegetable industry,and artificial light sources are widely used for seedling.The beginning stage of industrial vegetable breeding in China is later,but developed rapidly.However,at present,there are still some problems in the using of fill light to seedling,such as the mess of mixed light sources uneven quality,high energy consumption,unsatisfactory using effect and so on.In recent years,products of LED light sources with lower energy consumption for plant growth were imported and researched frequently,which creat a possible that the light conditions in process of seedling are well controled.For large-scale vegetable production company,the technical demand for industrial breeding is becoming more and more urgent,especially for the combination of light source for vegetable seedling with good versatility,energy saving and durability.In view of the above problems and industrial demand,three kinds of LED supplementary lights with different light quality(blue light type,red light type and remote red light type)were choosed as the test light sources,and the conventional fluorescent seedling light was used as the control.For the premise that the electric energy consumption is basically the same,six combinations of seedling light sources are designed.Taking tomato(Solanum lycopersicum)and cucumber(Cucumis sativus L.)as representative vegetable crops,the effects of different light source combinations on the seedling of two vegetable crops were compared,and the effects of different light quality ratio on the morphological and key physiological indexes of tomato and cucumber seedlings were studied.After repeated trials,the results were as follows.1.For the condition of the same energy consumption,when compared to fluorescent light,LED light source shorted the seedling period of tomato and cucumber.Meanwhlie,the seedling effect of LED light was significantly better than that of the control of CK1(fluorescent light source)(P < 0.05)in terms of growth index,root index,strong seedling index and daily dry matter accumulation under different treatments.2.Different combinations of LED light sources have different effects on seedlings,the treatment of 3(blue light accounted for 27.63%,red light accounted for 66.05%,far red light accounted for 6.31%)significantly increased the G value(daily dry matter accumulation)of tomato and cucumber,and improved the sound seedling index of tomato and cucumber seedlings(P < 0.05).3.Different light quality treatments have different effects on the growth indexes of cucumber and tomato seedlings: when compared to tomato,cucumber was more sensitive to the change of light quality.In a certain range,blue light(400nm-500nm)inhibited the elongation of hypocotyledonary axis and internode distance of tomato and cucumber seedlings,while red light(60nm-700nm)and far red light(700-800nm)promoted growth,but lead to the elongation of hypocotyledonary axis and internode distance.4.Raising seedlings in different stages(treatment 7 in the early stage,optimal light source ratio in the later stage)could significantly shorten the hypocotyl length and pitch of tomato and cucumber(P < 0.05),and could significantly increase the strong seedling index(P < 0.05).In conclusion,compared with traditional fluorescent light,LED light source has better seedling raising effect in tomato and cucumber seedling raising process.In treatment 3(blue light accounted for 27.63%,red light accounted for 66.05%,far red light accounted for 6.31%),tomato and cucumber had good seedling raising effect.Raising seedlings in stages(treatment 7 in the early stage,optimal light source ratio in the later stage)is more conducive to cultivating strong seedlings.