| Abstrakt: |
Two studies were conducted in 1988 to examine the effects of simulated acid rain in combination with various levels of drought stress on the grain yield of field grown corn (Zea maysL., ‘B73 × Mo17’ and ‘FS854’). In both studies corn was treated with twice weekly applications of simulated rainfall of pH 5.6 or 3.0 at amounts that totaled 100% (30 cm), 50% (15 cm), and 25% (7.5 cm) of the seasonal average for Champaign‐Urbana, IL. In addition to those treatments, in one of the studies the plants were subjected to daily wetting with the appropriate simulated rain from tassel emergence through pollination and fertilization. In both studies, reduced moisture levels resulted in significant reduction in grain yield but simulated rain of pH 3.0 had no effect on yield at any of the moisture levels studied. For both cultivars in both studies, reducing rainfall application from seasonal average to one‐half of the normal decreased yields by approximately 30%. When only one‐fourth of the seasonal rainfall amount was applied, yields were decreased between 40 and 55% compared to the yield for plants receiving the seasonal average rainfall. Results from these studies suggest that application of simulated acid rain of pH 3.0 has little or no negative effect on grain yield of the corn cultivars evaluated, even when relatively severe moisture stress was present, and when plants were subjected to daily wetting from tassel emergence through fertilization. |
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