Department of Soil Science, Michigan State University, East Lansing, Michigan (U.S A.)
*Present address: Ranchi Agricultural College, Kanke, Ranchi, Bihar.
In experiments, where there had been an opportunity for long term residual accumulations from previous fertilization and management, it was found that 45 kg of nitrate-N in the soil at tasseling represented a critical level for corn between response and no- response to fertilizer nitrogen. Low tests for nitrate in leaf tissues were found in case of nitrogen deficiency, when these developed before tasseling. After tasseling, however, low tests for tissue nitrate were found even at high levels of nitrogen availability.
Tissue test, nitrogen need of corn
