Evaluation of biocontrol effciency of different Bacillus preparations and Weld application methods against Phytophthora blight of bell pepper
Jiang. Z. -Q Guo. Y. -H Li. S. -M Qi. H. -Y Guo. J. H
Biological Control ; 2006 [Vol.36] Pages:216-223
Abstract
Biocontrol efficiency of various Bacillus preparations (BB11 and FH17 strains, and a mixture of both strains (BF) at a 1:1 ratio by
concentration) and diVerent application methods against Phytophthora blight of bell pepper were studied. The application methods included (A) mixing (mixing BF with rapeseed residue and then immediately applying in the Weld), (B) composting (mixing BF with rapeseed residue and made compost before application), (C) spraying (spraying diluted BF into Weld or rhizosphere of plants), and (D) watering (watering diluted BF into Weld or rhizosphere of plants). In greenhouse experiments, the addition of BF increased biocontrol eYciency (60.3%), and yield increase (200%) was better than with BB11 (55.8 and 80.6%, respectively) or FH17 (37.1 and 50.0%, respectively). In Weld trials at Huai’an in 2001, the best dosages of BF mixture (1010 cfu/ml) with the four above-mentioned application methods were 15, 7.5, 15, and 22.5L/ha, respectively. When preparations were applied at the best dosage in the same Weld, the BF mixture provided superior biocontrol eYciency and greater yield increase with treatment B than those with treatment A or C. Combining the Weld trial results from 2002 to 2003 at Huai’an and Wu’han, the total average control eYciencies and yield increases for treatments A, B, and C reached 81.0,88.0, and 79.1% and 33.1, 44.3, and 29.1%, respectively, with their best dosages. However, method B, composting, provided better disease control and greater yield increases than all other methods, and did so at a lower application rate.
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