ABSTRACT
During the 1986 and 1987 growing seasons, Paymaster 404 cotton plants were collected at weekly intervals from seedling emergence to harvest and the bacteria on various parts of the plants were enumerated and identified. The parts examined included roots, stems, branches, leaves, flowers, lint, bract and seeds. In this report, the results of standard plate counts on the total number of viable bacteria and on the number of viable gram negative bacteria on each part of the plant from specimens collected during 1987 are reported. Viable counts on each plant part were fairly constant throughout the growing season, with the exception of the roots where the total counts diminished with time. Bract had the highest levels of total and gram negative counts. During the 1986 season, the various types of bacterial colonies on each plant part were isolated and the organisms identified. Essentially the same organisms were present during the 1987 season. Identification of the bacteria was by conventional morphological and biochemical tests and by fatty acid profiles. The bacterial flora found on cotton plant parts were in the genera: Enterobacter, Serratia, Pseudomonas, Xanthomonas, Agrobacterium, Bradyrhizobium, Bacillus, Micrococcus, Staphylococcus, Corynebacterium, Oerskovia, Brocothrix, and Rhodococcus. Patterns of distribution varied on different parts of the plants.
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