Effect of Soil Moisture on the Transmission of Pseudomonas syringae pv. syringae From Seed to Seedling in Pea

Abstract

Glass-house studies showed that soil moisture had a significant effect on seed-plant transmission of P.s. pv. syringae. The number of infected seedlings increased from 3.7 to 39.2% with the increase in soil moisture in the pots from 10.0 to 30.0%. Most of the diseased seedlings that developed from inoculated and naturally infected seeds showed infection on the lower stipules whereas some of them showed infection on first, second and third stipule and also on first and second pair of leaflets, in a few plants, all the plant organs were infected, especially the apices which killed the young plants. A modei Y = 1/(0.2287 + (-0.0605 * In X) with a corrected R² value of 0.9320 derived to describe the relationship between the percentage of diseased seedlings (Y) and the soil moisture (X) when used to predict the percentage of diseased seedlings (PDS) for each year from 1990 to 1992 gave good fit between observed and predicted values in 12 out of 15 cases.