Abstract:

The objective of the study was to investigate the soil seed-bank of Portulaca oleracea in 0~20 cm soil layer, which collected from leafy vegetable fields in those farms with different cropping duration. The results showed that the Portulaca oleracea seed density of soil seed-bank enhanced with increased cropping duration. These results obtained from the laboratory were agreed with the real fact in the field. The Portulaca oleracea seed density of seed-bank gradually reduced along with the soil vertical depth increase, which was distributed mainly in the 0~15 cm soil layer, accounted for 98.5% of the whole seed-bank, and the seed density that in the 15~20 cm soil layer was especially lower. In addition, we investigated the dynamics of Portulaca oleracea seed density of soil seed-bank, and the results demonstrated that the highest seed density of soil seed-bank was occurred in the March and December quarters, respectively, while the seed density of soil seed-bank was relatively lower in the June and September quarters. The results of the happening in field had the contrary trend.