FIGURE 4 Flavonoids content of A. trifoliata in different habitats
Phenols are one of the most important secondary metabolites in plants. They are not only one of the components of the plant cell wall, but also can help plants resist the damage caused by various adversities (Ramirez et al., 2001). It can be seen from Figure 5 that with the growth and development of A. trifoliata , the content of total phenol in roots, stems and leaves showed an upward trend, and the content in leaves was the highest. At the same time, the increase rate of total phenol content in rocky desertification habitat was faster, and the content was significantly higher than that in normal habitat, especially in leaves. In Guanling base, the difference of roots was the biggest in October, increased by 1.46 times, stems was the biggest in September, increased by 1.30 times, leaves was the biggest in October, increased by 1.88 times; In Huaxi base, the difference of roots was the biggest in September, increased by 1.52 times, stem was the biggest in October, increased by 1.43 times, leaf was the biggest in September, increased by 1.57 times. In conclusion, rocky desertification can increase the content of total phenols in the root, stem and leaf of A. trifoliata .