Effects Of Phosphorus And Its Fertilization Position On The Growth And Yield Of Summer Cron (zea Mays L.)

To evaluate effects of phosphorus fertilization and its fertilization position on corn growth and yield, pot and field experiments were conducted on the farm of Henan Agricultural'University, Zhengzhou, China, from 2006 to 2008. The results are as follows:1. Root growth and development was improved by phosphorus fertilization. And there was difference among the treatments. Compared with shallow fertilization (5cm), corn root traits suchas root layers, root number, root length, root volume, dry matter accumulation and root activity were increased in treatment of phosphors deepen fertilization, and the increases in treatments of single soil layered deepen fertilization (15cm or 10cm) and two soil layered fertilization (5/15cm) were better than that in treatment of divided soil layer fertilization and three soil layered fertilization (5/15/25cm), respectively. There was a significant difference (P<0.05) among the treatments, except three soil layered fertilization and shallow soil fertilization, from 25 days after silking to maturity.2. Corn leaf area index (LAI), chlorophyll content and photosynthesis rate (Pn) were increased significantly in treatment of phosphorus fertilization. And there were significant difference among the treatments. LAI, chlorophyll content and Pn, from big to small, were phosphorus fertilized at 15cm,10cm,5/15cm,5cm,5/15/25cm soil layer, respectively. And the difference of LAI and chlorophyll content among the treatments was significant at maturity (P<0.05). However, there was a significant difference (P<0.05) of Pn among other treatments, except three soil layer fertilization and shallow fertilization, at 25 days after silking.3. Corn productivity increased significantly by phosphorus fertilization, while there was difference among treatments. Compared with the shallow fertilization (5cm), summer corn dry matter accumulation was increased in treatment of phosphorus deepen fertilization, and the increases in treatments of single soil layered deepen fertilization (15cm or 10cm) and two soil layered fertilization (5/15cm) were better than that in treatment of divided soil layer fertilization and three soil layered fertilization (5/15/25cm), respectively. The difference among the treatments was significant (P<0.05) in 2007. However, in 2008, the difference between treatment of 15cm and 10cm soil layer phosphorus fertilization was insignificant.4. The absorption and utilization of N, P and K from soil were improved in treatment of phosphorus fertilization, while there was difference among the treatments. Compared with the shallow fertilization, N, P and K accumulation and transfer were improved in treatment of phosphorus deepen fertilization, and the responses in treatments of single soil layered deepen fertilization (15cm or 10cm) and two soil layered fertilization (5/15cm) were more better than that in treatment of divided soil layer fertilization and three soil layered fertilization (5/15/25cm) during corn growing stage, respectively. The N, P and K transfer quantity, from big to small, were phosphorus fertilized at 15cm,10cm,5/15cm,5cm, 5/15/25cm soil layer, respectively.5. Summer corn grain yield increased in treatment of phosphorus fertilization. Among all treatments, grain yield was the highest in the treatment of phosphorus fertilizing at 15cm soil layer, reached by 12242.42 kg/hm2, followed by the treatment of phosphorus fertilizing at 10cm,5/15cm,5/15/25cm,5cm soil layer and the black control, respectively. In addition, there was no significant effect on improving gain yield in treatment of phosphorus three soil layered fertilization.In conclusion, phosphorus fertilization would be in favor of improving corn root growth.and development, which increasing absorption and utilization of N, P and K, and enhancing grain yield markedly Nutrition utilization efficiency could be hardly increased by phosphorus fertilized at 5cm and 5/15/25cm soil layer, and 5/15/25cm soil layer phosphorus fertilization not only increasing labor intensity and operation difficulty but also no significant effect on improving grain yield. In order to im proving summer corn growth and grain yield, the optimal method of phosphorus fertilization was deepen fertilizated from 10cm to 15cm soil layer.