The Influence Of LED Light On The Growth,Physiological Indicators And Qualities Of The Cucumbers In Solar Greenhouse

As the sole source of plant energy,light effects such properties of plants as growth and development.Natural light consists of many different light qualities,of which the most suitable wavelengths for plant growth are 400-450 nm(red light)and650-700 nm(blue light).In autumn and winter,light duration becomes shortened with many hazy days,which exerts great impact on the growth,development,yield and quality of the cucumbers in solar greenhouse.Therefore,the experiment adopts light-emitting diode(LED)to study the effects of different red and blue light ratios on the growth and quality of the cucumbers in solar greenhouse in autumn and winter.The results are as follows:LED fill light has a positive impact on the growth of cucumber seedlings.The growth indicator of the cucumber seedlings under the red-blue fill light is higher than that of CK.And the effect of T1 treatment on the plant height,leaf number,leaf area as well as dry weight and fresh weight above ground is significantly better than those of other treatments,indicating that the red-blue light ratio of 3: 1 can significantly promote the growth of cucumber seedlings.By the contrast of the photosynthetic characteristics,leaf pigment content and soluble protein content,it has been found that the fill light can enhance the physiological index of cucumber seedlings.Besides,The net photosynthetic rate,transpiration rate,chlorophyll content and soluble protein content of the cucumber seedlings under the fill light are all higher than those of CK.Based on the comprehensive growth and physiological indicators,T1 treatment is the best choice.That is,the proportion of red and blue light is 3: 1.After the fill light operation in the solar greenhouse in autumn and winter,the growth,yield and quality of cucumbers are improved.After 7 days of light supplementation,the leaf area of cucumbers enlarges evidently,but the plant height,stem diameter and leaf number have no obvious change.After 14 days,the cucumber diameter treated by T is significantly larger than that by CK,but the height of the cucumbers treated by CK is evidently higher than that of T treatment.After 21 to 35 days,the stem diameter,leaf number and leaf area are obviously larger than those of CK,but the height of the cucumbers by Ck is significantly higher than that of T treatment.After 35 to 49 days,plant height,stem diameter,leaf number and leaf area of T treatment are all larger than those of CK,but the difference is not apparent.Asfor the physiological indicators,the chlorophyll content,net photosynthetic rate,photochemical quantum efficiency by T treatment are significantly higher than those of CK.However,as for the fruit quality,the soluble sugar and soluble protein content by T treatment are obviously higher than those of CK.From the perspective of the apparent commodity,the single fruit quality,edible parts and fruit length of the cucumber by T treatment are better.According to the statistics of the yield,it has been found that the total output under T treatment is apparently higher than that of CK,reaching 12.1%.In conclusion,cucumber grows best in the red-blue light ratio of 3: 1.In autumn and winter,the light conditions in the solar greenhouse can be improved by the use of LED fill light,and meanwhile,the cucumber growth,yield and quality can be apparently bettered.