Effects of Different Tillage Measures on Soil Temperature and Humidity and Photosynthetic Capacity of Soybean

In this study, we investigated the effects of different tillage measures on soil environment and soybean yield. We chose a combination of eight tillage treatments using Heihe 43 as the test variety in order to correlate the yield with tillage practices. Our study design involved tilling and rototilling as primary treatments in combination with the following secondary treatment methods: advance deep loosening, advance cultivation, conventional deep loosening, and conventional cultivation. We investigated the effects of the above tillage treatments on soil physicochemical properties and soil biological activity. We also analyzed how tillage treatments impacted the morphology, photosynthetic characteristics, and yield of soybean. Our results indicated that tilling was more beneficial than rototilling in terms of increase in soil water content; the water content at the seedling stage increased from 5.80% to 17.13% in the 0–5 cm soil layer which was subjected to tilling. Under tilling conditions, the Pn, Tr, and Gs values of soybean plants were higher compared to those of soybean cultivated in soil subjected to rototilling. However, Ci values of soybean were higher in rototilled soil. In 2018, we observed an increase in the number of pods and grains per plant in PT1 and PT2 of tilling compared to that of RT1 and RT2 of rototilling. PT1 and PT2 showed a percentage increase of 9.12% and 7.33%, respectively. T1 and T2 both increased the number of pods and grains per plant of soybean under the same tillage conditions, which in turn increased the yield.