Analysis of yield potential of maize in different ecological regions in Jilin Province using Hybrid-maize model

Jilin Province is an major maize production area in China and it significantly contributes to national food security. Because of limited cultivatable land and adjustment of planting structure, the potential to increase maize planting area in Jilin Province is limited. Future increase in maize yield will mainly rely on yield improvement per cultivated unit area. Thus fully promoting the potential of maize production and per unit area yield constitutes an effective way of comprehensively improving maize productivity in Jilin Province. In this study, the Hybrid-maize model validated in Northeast China and long-term meteorological data combined with results of experiments of different maize varieties, sowing dates and planting densities were used to simulate maize potential yield in different ecological regions humid region (Huadian), semi-humid region (Gongzhuling) and semi-arid ecological region (Qian’an) in Jilin Province. At the same time, the driving factors of high and stable maize yield were analyzed based on potential yield variations and production characteristics of maize varieties. Finally, a high-yield system of maize was established. The main results of the study showed that: 1) Changing sowing date was a critical measure for yield increase. However, there were differences in performance among different ecological regions. Early sowing was required in humid region (Huadian), and the appropriate sowing date was about April 20. In contrast, late sowing was required in the other two ecological regions, with proper sowing times in mid-May. 2) The order of maize tolerance to high planting density for the different ecological regions in Jilin Province was: humid region (Huadian) > semi-humid region (Gongzhuling) > semi-arid region (Qian’an). The suitable densities in the three regions were 90 000, 80 000 and 75 000 plants·hm2, respectively. 3) Variety with longer growth period had higher yield potential. In practice, late-maturing variety selection depended on different regional ecological conditions. In semi-humid and semi-arid regions, it was necessary to increase GDD varieties to over 1 600 ℃ under current sowing date conditions. 4) According to the above results, the comprehensively optimized management measure for high-yield system was established, and the simulated long-term average yield potential of high-yield system increased by 14.39%–29.23% compared with the current production system. The study provided theoretical basis for proper cultivation measures of high-yield crop varieties. It also provided technical reference for large-scale production of maize in Jilin Province.