Effects of Intercropping Sweet Potato on Economic Characteristics, Physical Properties and Chemical Composition of Flue-Cured Tobacco

This study used the tobacco variety Yunyan 87 as the material and conducted a field experiment with a three-factor three-level orthogonal design to investigate the effects of different sweet potato varieties, intercropping time, and intercropping density on the economic traits, physical properties, and chemical composition of tobacco plants under the intercropping of tobacco and sweet potatoes. The results showed that the economic traits, physical properties, and chemical composition of the intercropped tobacco plants were slightly better than those of the control (tobacco monoculture). Compared with the control, the yields, value, proportion of superior and medium tobacco leaves is 10.25%-20.42%, 0.58%- 1.31%, 2.48%-8.71%, and 2.91%-7.95% respectively; the leaf length, leaf width, leaf thickness, leaf weight, and leaf weight of quality is 1.21%-2.27%, 1.54%-2.66%, 9.61%-14.0%, 2.26%-3.29%, and 6.20%-7.35% respectively; total sugar, reducing sugar, total nitrogen, nicotine, and potassium ions is 1.07%-2.23%, 1.93%-2.34%, 0.69%-0.86%, 0.31%-0.60%, and 0.46%-0.64%, while chloride ions is 14.28% - 21.01% in the intercropped plants. Although there were differences in the physical properties and chemical composition of the tobacco leaves under the intercropping treatment, the tobacco leaves from different parts all met the standards of high-quality tobacco leaves. Among them, the T5 treatment had the largest increase in yield (20.42%) and the proportion of superior leaves (7.52%). Therefore, from an economic perspective, it is recommended to adopt the T5 treatment when intercropping tobacco and sweet potatoes in Fuquan City.