Responses of three different corn cultivars to different fertilizer treatments


04 Feb 2008

2007 Annual Interpretive Summary

Responses of Corn Grown on Four Typical Soil Types to Different Fertilizer Treatments in Guizhou, 2007

This project was initiated in 2006 with the objective of studying the response of three selected corn cultivars to different fertilizer treatments at three locations, and to verify the optimal fertilizer rates for corn production in the province. In 2007, the study further aimed to quantify a suitable fertilizer scheme for Qiandan21, the high yield cultivar that is considered to have the best adaptability and is most widely grown in Guizhou, in four typical soil types (i.e., red soil located in the south, yellow earth and brownish yellow earth in the central, and purple soil in the north) in the province. There were eight fertilizer treatments including an optimal treatment (OPT), OPT-N, OPT-P, OPT-K, OPT+0.55N, OPT+0.6P, OPT+0.6K, and a zero fertilizer check (CK). The OPT treatment was adjusted on the basis of experimental results in 2006 and contained 165 kg N, 90 kg P2O5 and 112 kg K2O/ha.

The responsive trend of Qiandan21 to fertilization was similar in the three soil types except for the purple soil site in the north. The OPT produced the highest corn yield and it was most sensitive to N omission, followed by omission of K and then P. On the purple soil, the OPT+0.55N produced 271 kg/ha or 3% more corn yield than the OPT, though this yield difference was not significantly different. Corn yield varied considerably between soil types. The highest corn yields of 8.2 t/ha and 8.1 t/ha were produced on the purple soil in the north and in the red soil in the south, respectively. Since the weather is generally more favorable in the south, soil fertility might play a key role in corn yield formation. This finding is highly valuable in guiding regional fertilizer programs in future.

The verified fertilizer rates from this study can be recommended for the different regions and adjacent areas with the same soil types in Guizhou. They are 165-90-112 kg N-P2O5-K2O/ha for red soil in the south, yellow earth and brownish yellow earth in the central, and 180-90-112 kg/ha for the purple soil in the north. Guizhou-BFDP-06