Abstract:

To study the impact of climate change on winter wheat production in Linyi City and determine the suitable sowing time and appropriate field management measures, based on the meteorological data of Linyi City from 2001 to 2021 and the seedling survey data of agricultural and rural departments, as well as the historical weather data of Linyi City from 1962 to 2000, we adopted the linear trend prediction to analyze the change law of temperature and accumulated temperature during the winter wheat growth period and the date and duration of main growth stages. The results showed that the suitable sowing time and each growth stage of winter wheat in Linyi City had different responses to climate change. The suitable sowing time was from October 8 to 19, and the best sowing time was from October 11 to 14. The frequency of repeated cooling in tillering stage increased, which enhanced the cold resistance of wheat before winter and was conducive to the formation of strong seedlings; the increase of accumulated temperature before winter and the delay of overwintering period indirectly delayed the suitable sowing time, which could provide better conditions for the late harvest of maize of the previous cropping. The early returning green and significant increase of accumulated temperature after returning green greatly shortened the growth suspension and overwintering time of wheat, increased its actual growth time, and was conducive to the transformation of winter wheat seedling; the early jointing stage could make wheat be more vulnerable to late frost (cold) and late spring cold. The temperature drop in April and May provided better climatic condition for wheat heading, flowering and grain filling, especially, the temperature drop in May, which not only reduced the probability of dry hot wind, but was also conducive to wheat grain filling in the later stage. This study determined the suitable sowing time of winter wheat in Linyi City, and provided a basis for field management and high-yield cultivation of wheat in the whole growth period.

Key words: winter wheat, growth period, accumulated temperature, suitable sowing time, climate change