Abstract:
Using Dexue No.1 as the test variety, we set three factors: the color of the shade net (black, white and green), the shading rate (80%, 60%, and 40% of natural light), and the time to start shading (20 days, 25 days, and 30 days after transplantation). We employed an
L9(3
4) orthogonal design with 9 treatments, using the non-shading treatment as the control (CK). The effects of shading on growth, yield and quality of cigar wrapper were analyzed. The results showed that: (1) Shading affected the quality of light, and the color of the shade net as well as the shading rate could lead to different proportions of each spectral component. (2) The color of the shade net had a significant impact on the agronomic traits of the above-ground tobacco plants. After shading, there was an increasing trend in plant height and a decreasing trend in stem circumference. The white shade net could increase leaf area. When shaded with a black shade net, the growth period of the tobacco plants was extended. (3) The shading rate was the main factor affecting the biomass and root growth of the tobacco plants. After shading, the appearance and physical comprehensive quality score of the cigar wrapper tobacco leaves were significantly increased. Among them, the white shade net with a 40% shading rate treatment had the highest comprehensive score. In conclusion, the treatment of shading with a white shade net at a 40% shading rate has the best effect, and can be applied to the production of cigar wrapper tobacco leaves.