Dynamics of paclobutrazol in plant coil and its effect on the growth of Amorpha fruticosa

Paclobutrazol(PP333) can control the morphological and physiological characteristics of plants, and make them adapt to the sterile soil conditions of slopes. Therefore, it can be used for vegetation restoration. The dynamic variation rule of PP333 in the coil-plant system and its effects on plants were studied by model tests, which provide a reference for the application of PP333 in the vegetation restoration project. PP333 content in the vegetation coil and Amorpha fruticosa morphological index was determined to explore the dynamic changes of PP333 in vegetation coil and its effect on A. fruticosa growth. The results showed that: 1) the half-life of PP333 in different concentrations was between 15 and 60 days, and the elimination rate of PP333 in the coil was above 99% after one year. The runoff loss of PP333 in the coil was very small, and the loss during the experiment was only 1.81%, and the loss was negatively correlated with rainfall and rainfall time. 2)The rate of reduction of PP333 was 98% after one year, and the residue of PP333 was slag> sand> roof. The ratio of A. fruticosa PP333 to matrix PP333 in the three sites were 3.39%~14.24%, 4.90%~18.29%, and 6.14%~13.64%, respectively. 3) After one month of treatment with 20, 40, 60, 80, and 100 mg·L-1 PP333, the inhibition rate of the A. fruticosa height was 0.54%~14.66% and the rate of stem diameter increase was 8.67%~26.02%. The inhibition rate of A. fruticosa height was 15.09%~44.25% after one year, and there was no significant difference in stem diameter. The analysis of the morphological indices of A. fruticosa on the three types slope revealed that A. fruticosa growth was controlled by PP333and slope conditions.