Adjusting Sowing Dates Improved Potato Adaptation to Climate Change in Semiarid Region, China

Yields of rainfed potato (Solanum tuberosum L.) in China’s semiarid region are restricted by limited precipitation. Climate change could cause significant fluctuation in the rain-fed agricultural production due to the spatiotemporal changes in temperature and precipitation. As adjusting sowing dates proved to be an important management technique for improving grain yields, we examined how potato production can be improved by altering planting date in China’s semiarid region, thus improving potato adaptation to climate change. Field trials with five target sowing dates (from late April to early June) were carried out in Inner Mongolia, China during four growing seasons (2010–2013), and the effects of sowing dates on potato development, yield and water use efficiency (WUE) were estimated. Results showed that although delayed sowing shortened the duration of potato growth period, non-significant thermal time differences after flowering stage was found among the treatments. However, greater precipitation was shown in three intermediate treatments. Potato yield was significantly affected by sowing dates, and intermediate sowing dates showed greater yield compared to the earlier or later sowing dates. Delayed sowing dates significantly improved WUE in a drier year. As for a normal year, earlier sowing dates promoted WUE because of less water consumption, but these increases came at the cost of reducing yields. Under the current climate conditions in the study area, the flexible sowing time for potato was determined as from early May to early June, and optimum sowing time was between 10 May and 27 May. In conclusion, adjusting sowing date affected duration, thermal time, and precipitation over potato growth period, and the optimal sowing date exhibited higher yield by obtaining greater precipitation, which could improve potato adaption to climate change.