Figure 1. Frequency with which collections of bacterial isolates were found to stimulate the growth of strawberry seedlings in natural soil under controlled conditions. Collections of isolates were either not tested for antibiosis or were selected to be antibiosis positive before inoculations to seedlings.
Figure 2. Fresh weights of roots and shoots, and dry weights of roots and shoots (bars in order, left to right, for each isolate), of strawberry plants grown in a greenhouse experiment following inoculations with individual isolates of bacteria. The average weights per plant are shown for each isolate inoculated to plants at transplanting (G2, G7, etc.) and non-inoculated controls grown in non-sterile soil (CK2) and heat-sterilized soil (CK1). The bacteria used had antibiosis to one or more fungi and all inoculations except G7S were transplanted into non-sterile soil. Weights are expressed as a percentage of that obtained for non-inoculated controls in non-sterile soil (CK2).
Figure 3. Total berry yields of plants inoculated with individual bacteria at MBA, Watsonville. Yields of market quality berries were measured as the totals obtained in weekly picks from April through August, 2000. Soil was either fumigated with a standard rate of MBC, with a low rate of Pic, or not fumigated (NT). Plants were inoculated at transplanting with one of four bacteria designated on the X axis as P1, P2, P3, or K4, and a subset of each bacterial treatment also received multiple inoculations during crop growth (red vs. blue bars). There were two noninoculated controls: NT treated with only a buffer; and K4 treated with carrier without the K4 bacterium (yellow bar). Yields are given relative to that obtained without inoculation in standard methyl bromide/chloropicrin fumigated soil.
Figure 4. Total berry yields of plants inoculated with individual bacteria or a fungus at MBA, Watsonville. Yields of market quality berries were measured as the totals obtained in weekly picks from April through August, 2001. Soil was either fumigated with a standard rate of MBC, with a low rate of Pic, or not fumigated (NT). Plants were inoculated at transplanting with one of five bacteria designated on the X axis as 1, 3, 4, 5, or 6, and a subset of bacterial treatment 3 also received multiple inoculations during crop growth (3R). Additional sets of plants were inoculated with the fungus Trichoderma harzianum strain T-22 or were not treated (NT, green bars). Yields are given relative to that obtained without inoculation in standard methyl bromide/chloropicrin fumigated soil.
Figure 5. Final incidence of plants with visible symptoms of Verticillium wilt on non-treated soil in August, 2001. This is the same experiment as shown in Figure 4 but only the inoculation treatments done on non-treated soil are shown.
Figure 6. Total berry yields of Aromas plants inoculated with individual bacteria and grown on non-fumigated soil at MBA, Watsonville. Yields of market quality berries were measured as the totals (grams/plant) obtained in weekly picks from April through August, 2002. Plants were inoculated at transplanting with one of five bacteria designated on the X axis as FP3, FP7, etc. Isolates K3 and K4 were applied with carriers applied separately as treatments K1 and K2, respectively.
Figure 7. Total berry yields of plants obtained in 1999-2000 experiment I at SCREC, Irvine. Relative yields are given as percentages of the yield obtained with noninoculated, bare-root plants in MBC-fumigated soil. Bare root (red bars) and plug plants (blue bars) were inoculated with one of two bacteria designated on the X axis as P2 and P3 or where not inoculated (NT). Inoculations were done at transplanting and repeated twice during crop growth. Effects of inoculation treatments within each soil treatment were not statistically significant.
Figure 8. Total berry yields of Camarosa plants inoculated with individual bacteria at SCREC, Irvine. Yields of market quality berries were measured as the totals obtained in weekly picks from December, 2001, through March, 2002. Soil was either fumigated with a standard rate of MBC, with metam sodium, or not fumigated (NT). Plants were inoculated at transplanting with one of seven bacteria designated on the X axis as FP3-9. There were noninoculated controls (CK, red bars) for each soil treatment. Yields are given relative to that obtained without inoculation in standard methyl bromide/chloropicrin fumigated soil.