Abstract:

To study the effect of paclobutrazol spraying on the seedling growth of double cropping late rice and provide technical support for the management of matrix seedlings, ‘Huayou2’ was chosen as the material to analyze the effect of concentration and time of paclobutrazol spraying on the quality of matrix seedlings through the rice seedling nursery experiment. Results showed that paclobutrazol spraying significantly delayed the seedling growth of rice, the seedling height decreased significantly. The regulating effect of paclobutrazol spraying on the seedling height enhanced as the spraying concentration increasing, and weakened as the spraying time putting off. Paclobutrazol spraying significantly influenced the chlorophyll content of the rice seedling, the SPDA value had extremely significant difference between the spraying time (T) and concentration(C) treatments, and had significant difference among the spraying time (T) × concentration (C) treatments. With a certain concentration, the root amount, length and root vigor increased significantly with the spraying concentration increase. Too high concentration and delayed spraying time inhibited the root growth. In consideration of rice seedling height, the chlorophyll content and root growth, the rice seedling quality is optimal under T₁C₂ and T₂C₂ treatments.

Key words: Matrix Seedlings, Paclobutrazol, Spraying Time, Spraying Concentration, Seedling Quality