Abstract:

Food production has obvious regional characteristics. The weed seed banks are greatly different under the different cropping systems between the different crops. This paper studied the weed seed banks in 72 wheat-maize grain crop field under the rotation system of Xi′an through the soil sampling, indoor inducing sprouted and field investigation. The results showed that: (1) The average amount of weed seeds was 11351.70 /m2 at 20 cm soil layers in grain crop fields of Xi′an. The active weed seeds amounted accounts for 3.50%, the actual field weeds amount accounted for 0.51%. (2) The weed seeds amount of different ecological crop field varies greatly: tableland>hillside>irrigated plain area>flood land. The irrigated plain area was the main grain crop fields in Xi′an. The weed seeds amount was lower than tableland’s and hillside’s with 11044.44 /m2. (3) The weed seeds amounted at 7-14 cm, soil layers accounted for 37.04%. It was slightly more than the amount at 0-7 cm and 14-20 cm soil layers.