Abstract: The mechanisms of antagonism between Trichoderma harzianum and Fulvia fulva in
tomato leaves were analyzed using combined indoor screening and field efficacy trial. All five testing
strains had distinct inhibitory effects to tomato leaf mould disease by the antagonistic experiments. The
inhibitory effects of strains TH16 and TH54 were the strongest in all the tested strains. Field efficacy trial
results showed that the optimal concentration of spores suspension were 108 per milliliter. The control
effects of TH16 and TH54 were 69.4% and 60.0% respectively. Net photosynthetic rate，intercellular CO2
concentralion，stomatal conductance，light saturated rate of the CO2 assimilation（Asat），maximum
carboxylation rates（Vcmax）and maximum RuBP regeneration rate（Jmax）were increased significantly after
the inoculation of tomato leaves with T. harzianum. Activities of ribulose-1,5-bisphosphate
carboxylase/oxygenase Rubisco and stromal fructose-1,6-bisphosphatase（FBPase）and genes expression
levels encoded Calvin cycle enzymes increased in tomato plants inoculated with T. harzianum TH16. However，leaf mould disease infection resulted in lower net photosynthetic rate，Vcmax and Jmax value.
Meanwhile，the inhibition of Pn，Asat，Vcmax and Jmax could be recovered in the plants infected with leaf
mould disease if pre-inoculated with T. harzianum. The expression levels of the genes encoded Calvin
cycle key enzymes could be induced in the plants inoculated with T. harzianum. The expression levels of
FBPase，FBPA，SBPase and TPI were increased 6.53，3.51，5.17 and 7.81 times of the control respectively.
The results showed that T. harzianum invoked a range of related enzymes and genes to facilitate
photosynthetic metabolism against leaf mould disease.

Key words: tomato, Trichoderma harzianum, antagonistic effect, tomato leaf mould disease, photosynthetic characteristics