ISSN:
1573-8469
Keywords:
fosetyl
;
phosphonate
;
ethephon
;
phosphomycin
;
median effective dose
;
antibacterial activity
;
Pseudomonas syringae
;
pear
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Several phosphonate derivatives including theoomycetic antifungal agents phosphonate andtris-o-ethylphosphonate (fosetyl), theethylene-releasing compound 2-chloroethylphosphonate(ethephon), and the antibiotic2-epoxypropylphosphonate (phosphomycin) were evaluatedfor in vitro and in planta activityagainst Pseudomonas syringae pv. syringae.Inhibition of colony growth in CYE agar byphosphonate, fosetyl and etephon was very slight(minimal inhibitory concentrations MIC= 0.31–;0.62 gHP $$O_3^{2 - } $$ /l). Also, survival of P. syringae pv. syringae in aqueous solutions ofphosphonate or fosetyl was high. Only phosphomycinshowed significant antibacterial activity invitro (MIC=10-20 µg HP $$O_3^{2 - } $$ /ml) comparedto streptomycin (1-2 µg a.i./ml). Potted pearplants irrigated with these chemicals and inoculatedwith Pseudomonas syringae pv. syringae had significantly less disease than non-treatedcontrols ( P〈0.001). Phosphomycin was the mostactive compound with a median effective dose(ED50) of less than 0.62 g HP $$O_3^{2 - } $$ /l.Activities of the other phosphonates were weak butconsistent between experiments. The ED50s on wholeplants were 2.1, 3.3, and 6.9 g HP $$O_3^{2 - } $$ /l for ethephon, phosphonate and fosetyl, respectively. TheED50of P. syringae pv. syringaeincreased from 6.5 in non-treated controls to 7.7-8.8log10 cfu/ml on plants treated with phosphonatesat 1.86 g HP $$O_3^{2 - } $$ /l. It was concluded thatdrench treatment with fosetyl is not a practicaloption for control of P. syringae pv. syringae on pear.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1008623616762
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