Yield gap simulations using ten maize cultivars commonly planted in Northeast China during the past five decades

Abstract

Northeast China (NEC) is one of the most important agricultural production areas in China and is one of the most sensitive areas in the country to climate change, particularly during the last five decades when strong climate warming occurred. Thus, a better understanding of the potential, attainable, and farm yields and yield gaps of spring maize under climate change is necessary with respect to historical cultivars improvements. Ten spring maize cultivars commonly planted from the 1960s to the 2000s were selected for a two-year field experiment in Lishu, NEC. The APSIM-maize model was used to simulate the potential and attainable yields of spring maize from 1961 to 2009 using real-time cultivar calibration and validation during the past five decades. Our results indicated that the yield gap between the potential and farm yields was 9.7tha−1, or 66.2% of the potential yield; the yield gap between the attainable and farm yields was 5.6tha−1, or approximately 54% of the attainable yield. Climate change from 1961 to 2009 led to a reduction in the potential yield by 2.1% and a reduction in the attainable yield by 8.0%. Improved cultivars and agricultural practices have led to an increase of 62.2% and 80.5% in potential and attainable yields, respectively. Therefore, the combined impact of climate change and improvements in cultivars and agricultural practices increased potential and attainable yields 53.3% and 70.3%, respectively, for the period 1961–2009 relative to the yields of the cultivar planted in the 1960s. In conclusion, improvements in cultivars and agricultural practices for spring maize in NEC played a dominate role for the increase of yield, and the persistent large yield gap between farm and attainable or potential yields provides farmers an opportunity to increase their agricultural production.