Assessment of resilience in maize suitable planting areas under drought stress

Abstract

Crop resilience refers to the adaptive ability of crops to resist drought at a certain level. When the degree of drought stress did not exceed the resilience range of the crop, the crop could recover even exceed normal growth after rehydration. However, the assessment of crop resilience lacks considerations on mechanisms. Focusing on the suitable maize planting areas in China, this study took relative soil humidity (RSH) as the index to screen drought and rehydration events, identified the resilience mechanism of maize under drought and rehydration conditions, and determined the correlation between resilience and RSH. The results shown that the strongest resilience were found in the northern part of the North China Plain (NNCP), the central part of the North China Plain (CNCP), the central-eastern part of the North China Plain (ENCP) and the North Anhui Plain (NAP), followed by the Guanzhong Plain (GP) and the Central Sichuan Hills (CSH), and the Songnen Plain (SP) had the weakest resilience. Based on the relationship analysis between RSH and the resilience of maize under drought stress, maize had resilience when 34%≤RSH≤ 54%, and the resilience increased with the decreasing RSH. When RSH< 34%, the drought stress exceeded the resilience of maize, maize cannot resume normal growth after rehydration. Therefore, bases on the resilience mechanism of maize to drought and combined with the monitoring of RSH, irrigation in an appropriate period can maximize water-saving, which provides supports for drought risk response and efficient utilization of water resources.