Abstract: Seedlings growth of Chinese lettuce were dated under combination of 3 kinds of activated charcoal and 3 use patterns of soil respectively in Yangling region. An activated fir charcoal was picked up for making coupled biochar with endophytic bacteria, Bacillus sp., and the coupled fir biochar was further tested in pot planting with winter wheat. Results showed that of three charcoals, activated coal, activated coconut carbon and activated fir charcoal, significantly affected the growth of Chinese lettuce, as well as interactions between charcoal and soil. Fir charcoal showed 178.8%/90.9% and 178.9%/106.1% net carbon rate of promotion on hypocotyl/radicle of lettuce seedlings in agriculture soil and peach orchard soil respectively. Whereas, the acid activated coal showed -120.7% inhibition net rate to the growth of hypocotyl in the acid soil from Cedar stands. Therefore, fir charcoal was picked up for preparing an innovative biocharcoal by coupling with endophytic bacteria Bacillus sp. under 40 ℃ for 30 min, and then incubated at 27 ℃ for 1 d. The coupled biochar was found with potential function for growth of wheat stressed in 1% salt soil. The coupled mixture can improve the water holding capacity of soil. Seedlings in the group with combination of 3 g coupled fir charcoal and 1 250 g agriculture soil significantly promoted height rate at 37.3% (α=0.05 ) in 10 d, and the promoted biomass rate in the group with combination of 6 g coupled fir charcoal and 1 250 g agriculture soil were 18.8% (α=0.05) in 20 d. The latter was thought to be the optimal dosage in the tested groups for winter wheat with good height promotion and biomass promotion.

Key words: activated charcoals, coupled biochar with bacteria, lettuce, wheat