Studies On Paclobutrazol (PP333)'s Influence On Some Physiological Effects And Yield Of Cassava

Take variety GR911 as testing material, spray 500mg.L-1 and 1000mg.L-1 paclobutrazol (PP333) solution on leaves during expanding period of root tubers, test regularly related indexes of the agronomic characters, photosynthesis and electrolyte penetration, enzyme activity, proline, MDA and the content of soluble sugar and starch and the total content of nitrogen and protein to search the effect of PP333 on cassava's growth, yield and quality. Results through statistical analysis as follows: 1. PP333 shortens the plant height and leaf stalk, enlarges the cane androot/crown ratio, and regulates effectively the growing relation betweenparts on and under the ground, 2. PP333 increases the content of photosynthetic pigment, weight of unite leaf,net photosynthetic and stomata conductance, improves the photosyntheticquality and promotes the photosynthetic material accumulation, 3. PP333 reduces the content of soluble sugar, but increases the total content ofnitrogen and protein, delays the aging of leaves and promotes the expandingof later stage root tuber. 4. PP333 improves the activity of such protective enzymes as POD, CAT, SODand so on, increases the content of proline but reduces content of MDA, thusimproves the ability of resistance to adverse condition. 5. PP333 increases the yield and content of starch, and improves technologicalcharacters. 6. Treatment of 500mg.L-1 better than that of 1000mg.L-1 in both yield andquality and other physiological effects.