PREDICTING BEHAVIOR OF IPIPHYTIC BACTERIA IN THE GROWTH CHAMBER FROM FIELD STUDIES

Authors: Upper, Christen; HIRANO, SUSAN - UNIVERSITY OF WISCONSIN

Submitted to: International Symposium on Microbiology of Aerial Plant Surfaces
Publication Type: Abstract Only
Publication Acceptance Date: 9/15/1995
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Use of a controlled environment facilitates experimental manipulation, diminishes environmental variability and provides the means to separate variables and test hypotheses. One common assumption is that results of experiments in such environments should be relevant to the phenomenon of interest in the field. For many kinds of plant-microbial studies, results of experiments in controlled environment facilities have been readily applicable to the field. However, there are some kinds of studies for which controlled environments may not serve particularly well as surrogates for the field. The interaction between Pseudomonas syringae pv syringae (Pss) and snap bean leaflets provides several examples in which the plant-bacterial interaction behaves differently in the field as compared to the laboratory. Field symptoms of bacterial brown spot disease on either leaves or pods are different compared to those on growth chamber-grown plants. Numbers of pss on cultivar Eagle may be as much as 1000-fold greater than on Bush Blue Lake 94 in the field, but approximately equal in the growth chamber. When sprayed onto bean leaves in the growth chamber, pss grows, particularly when the plants are reasonably moist. In the field, even when leaves are wet with dew at night, populations of Pss decline or remain static. Occasional bursts of rapid growth, usually triggered by intense rain, give rise to large populations of the bacterium on plants in the field.