Effects of nitrogen fertilizer management, organic manure application and bed-irrigation sowing on maize yield, and nutrient uptake and translocation

This study was conducted to determine the effects of nitrogen fertilizer management, organic manure application and bed-irrigation sowing on maize yield, dry matter accumulation, uptake and translocation of N, P and K, and nitrogen recovery rate. The results showed that proper nitrogen fertilizer management, organic manure application and bed-irrigation sowing significantly increased spring maize yield. The average yield increase was 10.6%–17.0% for nitrogen fertilizer top-dressing for two times, 10.3%–18.0% for organic manure application, 9.1% for bed-irrigation sowing, and 20.4% for the combined organic manure application and bed-irrigation sowing compared to nitrogen fertilizer top-dressing for one time, respectively. Significant increase in rate of maximum dry matter accumulation and total accumulation amount of dry matter was observed by nitrogen fertilizer top-dressing for two times, organic manure application, and the combined organic manure application and bed-irrigation sowing compared to nitrogen fertilizer top-dressing for one time, with respective increase of 11.1%–29.5%, 28.0%–28.8% and 32.1% for rate of maximum dry matter accumulation, and 11.9%–15.5%, 21.2%–24.4% and 26.9% for total accumulation amount of dry matter. Maximum uptake rate and total uptake amount of N, P and K increased obviously by nitrogen fertilizer top-dressing for two times, organic manure application, and the combined organic manure application and bed-irrigation sowing. A general order was followed by K N P for maximum nutrient uptake rate, N K P for total nutrient uptake amount, and K (57.2–60.4 d) N (65.3–68.5 d) P (71.4–74.8 d) for the appearing time of maximum nutrient uptake rate, which were earlier than that of maximum accumulation rate of dry matter (82.5–89.3 d). Remarkable increase in translocation amount and efficiency of N, P, K from vegetative organs to grains, nutrient content in grain, and nitrogen recovery rate was found by nitrogen fertilizer top-dressing for two times, organic manure application and bed-irrigation sowing, and proportion of nutrients in grains was followed by P (59.3%–66.1%) N (41.5%–55.1%) K (35.9%–38.0%). Under the experiment conditions, the recommend fertilizer formula was nitrogen applied 225 kg/ ha with 1/4 nitrogen fertilizer applied as basic fertilizer and 3/4 as jointing fertilizer combined with organic manure application and bed-irrigation sowing.