Effects Of Different Farming Measures On Canopy And Root Of High Yield Spriug Maize

In order to further explore potential ways of improve production of high-yielding spring maize, the experiment used ordinary rotary tillage, subsoiling, deep plowing with straw return to field to find the effect of different tillage on delaying high-yeilding spring maize senescence and increaseing mazie production. Deep plowing within straw breaked solid plough pan, improved soil quality, and can slowed down the senescence of canopy and increased yield significantly. Besides, through further tap on root vertical expansion, the experiment fined out the relative photosynthetic contribution rate of different layer root to high-yidleding spring maize production. The results were as follows:1. Compared with ordinary rotary tillage and subsoiling, deep plowing within straw significantly improved yielding spring maize production. Yield components indicated that deep plowing within straw increased yield significantly by improving maize grain weight. Between two spike types, the yield and grain number of high stalk with large ear were higher than medium stalk with medium ear’s. But grain weight and bare tip length were of smaller high stalk with large ear than medium stalk with medium ear’s.2. Compared with ordinary rotary tillage and subsoiling, deep plowing within straw improved canopy photosynthetic capacity, SPAD, Fv/Fm, Fv/Fo and LAI effectively at flowering and milking stage, while delayed senescence of high-yielding maize leaves. Between two spike types, high stalk with large ear’s photosynthetic capacity was higher than medium stalk with medium ear’s, and high stalk with large ear was more sensitive to the changes of farming methods.3. Compared with ordinary rotary tillage and subsoiling, deep plowing within straw improved the bio-accumulation of high-yielding spring maize. The dry matter accumulation of two spike types were higher than other treatments. Between two spike types, the dry matter weight of high stalk with large ear was higher than medium stalk with medium ear’s at the first day after pollination. But, at the fifteenth day after pollination to maturity, the dry matter weight of high stalk with large ear was lower than medium stalk with medium ear’s.4. Compared with ordinary rotary tillage and subsoiling, deep plowing within straw improved activity of SOD, while reduced the activity of POD. There were no significant difference between two spike types.5. Compared with ordinary rotary tillage and subsoiling, deep plowing within straw coordinated the source-sink relationship in maize. Deep plowing within straw improved grain-leaf ratio and increased photosynthetic contribution rate of every layer leaves, but reduced kernel abortion rate. Between two spike types, from1st-15th day after pollination, high stalk with large ear’s grain-leaf ratio was higher than medium stalk with medium ear’s, but from15th-45th day after pollination, high stalk with large ear’s grain-leaf ratio was lower than medium stalk with medium ear’s. The photosynthetic contribution rate of every layer leaves of medium stalk with medium ear was higher than high stalk with large ear’s. On the contrary, medium stalk with medium ear’s kernel abortion rate was lower than high stalk with large ear’s.6. Three farming methods indicated that leaf photosynthetic contribution rate above ear was higher than leaf photosynthetic contribution rate of ear, and leaf photosynthetic contribution rate of ear was higher than leaf photosynthetic contribution rate below ear. It was because leaf number above ear was more than the other layer leaf number, received a good sunshine. But the leaf photosynthetic of ear was strongest than the other layer leaf’s photosynthetic. Besides, leaf below ear had been dead.7. With the increasing of root vertical distribution, the space and soil nutrient were raised. So, root biomass in deep soil layers was raised. For the roots going deeper and expansion of20cm, root dry weight will increased by19.54percent on average, while production increased by17.91%on average.In summary, deep plowing within straw improved photosynthesis capacity, coordinated the source-sink relationship, delayed maize senescence and ultimately increased maize production. With the roots going deeper, this enlarged source capacity of root, and finally increased yield. After the high-yield records predecessors have created, deep plowing within straw and increaseing the amount of deep roots of high-yielding spring maize will be a effective method to further improve maize yield in Inner Mongolia.