| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4506619 | Crop Protection | 2011 | 7 Pages |
The overreliance on and overuse of fungicides is not only a health hazard but also induces natural resistance in plant pathogens, resulting in an economic burden on agricultural producers and a potential threat to natural systems across the globe. It is therefore necessary to identify natural substitutes of fungicides. This study was designed to evaluate the inhibitory effect of the root exudates of two different garlic cultivars, cv. Gailiang (G064) and Cangshan (G025), against Phytophthora capsici, a pepper fungus. All treatments (T1 to T4, i.e., 25%, 50%, 75% and 100% root exudate concentrations) of garlic cultivar G025 showed lower inhibition effects than cultivar G064. An intervarietal inhibition effect comparison at 100% concentration (T4) exhibited a 69.24% decline in hyphal growth for G064 compared with 49.06% for G025. The mycelial growth measured in the control was found to be significantly greater compared with the garlic treatments. The results of high performance liquid chromatography (HPLC) revealed that G064 possessed a large amount of allicin compared with G025. Scanning and transmission electron microscopy showed that, compared with the controls and hyphae treated with G025, the fungal hyphae treated with G064 exudates were misshaped, fragmented and had a smaller diameter, as well as empty cytoplasmic contents in the cell wall. Thus, the root exudates of the G064 cultivar had a significant fungicidal effect on P. capsici.
► This study provides basis for the development of non-chemical treatment against Phytophthora blight of pepper. ► On comparison of the anti-microbial effects of root exudates it was found that two garlic cultivar have different inhibition effect on the fungi of phytophthora blight of pepper. ► It was recorded that inhibition rate changed with the contents of allicin in the garlic root exudates. ► Both garlic cultivars showed different effect on the cell structure of fungi observed by electron microscrope both in scanning and transmission.
