Improving tomato yield, quality and antioxidant capacity in greenhouse by far-infrared radiation

Abstract

Far-infrared radiation is known as the "light of life". To investigate if it has positive effects on tomatoes and the proper location and time period of the far-infrared treatment. This study adopted tomato 'Taiji No.1′ as the plant material with 8 μm-14 μm far-infrared treatments. The results found that far-infrared radiation can significantly increase antioxidant capacity of senescent leaves. The proper location of the far-infrared lines was placed at the root and growth layer of the plant, which enhanced the net photosynthetic rate of plants by 44.01 % compared with the CK (no far-infrared treatment). It also promoted fruit ripening and increased the yield by 20.25 % compared with the CK. For the time period, far-infrared treatment during the periods of 6:00–9:00 am (gradual increase in photosynthesis) and 15:00–18:00 pm (gradual decrease in photosynthesis) (DT6) showed the optimum effect, which even surpassed 24 h and 16 h far-infrared treatments. The net photosynthetic rate of DT6 increased by 31.05 % compared with the CK (no far-infrared treatment). Among all the treatments, DT6 had the highest soluble sugar, fructose, and glucose contents. Among the common aroma compounds of tomato, sweet-related compounds were higher in the far-infrared treatment group than in the CK. DT6 treatment also had the highest yield and profit margin.