Abstract:

The summer soybean ‘stay green’ occurs occasionally in southwest Shandong in recent years, and it causes serious loss in some years. To explore the potential reasons of this phenomenon, the study conducted two experiments to illustrate the effects of temperature and Riptortus pedestris on summer soybean ‘stay green’ in two counties of Jining City. The experiments of different sowing dates of the same soybean variety and different treatments of the same soybean variety at the same sowing date were carried out to explore the effects. Different soybean varieties all had a relatively good yield with different sowing dates in 2019-2020; while under different treatments of the same variety at the same sowing date, except the difference of the yield, there was no any large scale of ‘stay green’, and the rate of the phenomenon was below 2%. Preliminary result demonstrated that the outbreak of soybean ‘stay green’ in 2018 in southwest Shandong Province was related to the high temperature in flowering and podding stage, which had nothing to do with Riptortus pedestris. It is suggested that farmers should postpone the sowing date of summer soybean and strengthen the field management, which are important to the production of soybean.

Key words: soybean, stay green phenomenon, high temperature, sowing date, Riptorus pedstris, Jining City