Tomato is one of the most important agricultural products, which ranks second in the world after potatoes in terms of production and yield. Tomato is one of the most demanding plants in terms of light requirements, and the lack of light, especially in the winter months and in the cloudy areas of the north of the country, reduces the growth and development of the plant and disrupts the formation of flowers and fruits. In fact, tomato needs light for many activities such as photosynthesis, flowering, growth, and the production of many metabolites and the expression of its genes. Studies have shown that the use of LED lights, especially in low light seasons, increases the yield of tomato fruit. In this study, tomato seedlings of Sakhiya RZ variety produced by Rijk Zwaan company in the Netherlands were cultivated in the greenhouse of Dasht Naz Sari agricultural company in rows with a row spacing of 1.6 meters and within-row spacing of 30 cm. They were treated with LED lights from flowering to the end of the production season. This experiment was conducted in the form of a randomized complete block design in 4 replications with 10 plants in each replication. The treatments included plants receiving light from LED growth lights and plants without receiving light through growth lights as controls. The growth lights used in this experiment were also used in three modes: top lighting, inter-lighting, and combined top and inter lighting. The number and weight of tomatoes harvested per plant on a weekly basis, the amount of vitamin C and lycopene in the fruit in the treatments and the expression of key genes affecting flowering, production of metabolites and antioxidants of tomatoes were eva‎luated. LED exposure, especially the light from inter-lighting, increased the yield of tomato fruit from November and July between 10 and 150% and on average during the period of growth and production, the yield increased by 30.8%. Inter-plant exposure also increased fruit lycopene (31% on average) and tomato fruit vitamin C (123% on average). The increase in tomato fruit yield as a result of LED exposure in the greenhouse can be caused by the increase in flowering and the increase in the number of fruits as the main component of the yield, as well as the increase in photosynthesis and cellular signaling of tomato plants. LED light had a positive effect on the expression of genes of different production cycles and tomato metabolites, and a very significant correlation was observed between the expression of some genes, including Psy1, β-LCY and VTC2, with the number of tomato fruits and fruit yield per plant.

مجيد طالبي، بدرالدين ابراهيم سيد طباطبايي

محمدرضا سبزعليان

آقافخر ميرلوحي، ابوذر سورني