Phenological Changes of Soybean in Response to Climate Conditions in Frigid Region in China over the Past Decades

Abstract Plant phenology becoming a focus of current research worldwide is sensitive indicator global climate change. To understand observed soybean and explore its climatic determinants in frigid region (Northeast China northeast Inner Mongolia), we studied the phenological changes [ Glycine max (L.) Merr.] for during 1981–2017, then analyzed contribution major causal factors to based on multiple stepwise regression. Altogether, average temperature from sowing maturity (WGP) was significant increasing, accumulated precipitation sunshine hours were decreasing. More than 50% observations showed delays sowing, emergence stage short durations flowering (VGP), (RGP) (WGP). The late getting following timing backward, but delaying trends much less that due warming accelerated growth soybean. Detailed analysis indicated mean 1–3 months immediately preceding emergence, dates influenced higher latitude areas (HLJ FL), while JL LN, hours(replacing temperature) determinants. These results brought light importance policy support strategies adaptation local condition under