Growth-promoting effects of Trichoderma citrinoviride HT-1 mixed with humic acid on wheat

【Objective】To explore the effects of combining Trichoderma citrinoviride HT-1 and humic acid on wheat seed germination，as well as seedling growth and development，in order to provide scientific basis for the high quality and yield of wheat，and lay a theoretical foundation for the development of new compound microbial fertilizer.【Method】On the basis of measuring the effects of different concentrations of humic acid on the growth of strain HT-1 and screening the best mixed concentration，the effects of mixed strain HT-1 spore suspension and humic acid on wheat seed germination and seedling growth were studied through seed germination and pot experiments.【Result】Different concentrations of humic acid had certain effects on the growth of strain HT-1，among which 0.1 g/L humic acid had no significant effect on the colony growth and sporulation of strain HT-1 （P＞0.05）. The germination index of wheat seeds， the biomass of potted seedlings，root activity and chlorophyll content of wheat seedlings reached the maximum after the mixed treatment of strain HT-1 spore suspension and humic acid at a ratio of 1∶1. Compared with the control group（CK）of sterile water，the seed germination related indexes［germination percentage（GP），germination energy（GE），germination index（GI）and vitality index（VI），plumule length，radicle length，fresh weight and dry weight］ were significantly increased by 3.47%， 6.92%，8.03%，195.33%，94.37%，176.09%，40.16% and 18.92%（P＜0.05，the same below）respectively. The potted seedlings biomass（plant length，root length，whole plant fresh weight and the whole plant dry weight）were significantly increased by 41.63%，49.79%，48.57% and 73.63% respectively. Root activity and chlorophyll content were significantly increased by 68.85% and 43.50% respectively. At the same time，it was significantly higher than the effect of single strain HT-1 spore suspension or humic acid treatment.【Conclusion】Different concentrations of humic acid have a certain effect on the growth of T. citrinoviride HT-1，and 0.1 g/L humic acid has the least effect on the growth of strain HT-1. When the spore suspension of strain HT-1 is mixed with humic acid at a ratio of 1∶1，the germination-related indexes of wheat seeds， biomass of potted seedlings， chlorophyll content and root activity all reached the maximum， which are significantly higher than the growth-promoting effect of single application of the two.