All varieties listed in Table II need further evaluation to determine their long-term performance. Soybean varieties with potential chlorosis tolerance based on seed yield for one or two years of field testing. One year data only Table III lists the other varieties that have been evaluated but did not have adequate tolerance to alkaline soil conditions or do not have seed available. New varieties will continue to be developed, and some will have good tolerance to high pH soils. Soybean varieties that have been evaluated on high pH soils, but are not adequately tolerant to chlorosis or seed is not available for production.
Research shows that even with tolerant varieties, seeding density is important.
Chlorosis is more severe when plant density is low. Therefore, the suggested seeding rate is 12 viable seeds per foot of row, regardless of row spacing. Row spacings of less than 20 inches are not practical because the suggested seeding density within the row results in an excessive plant population. The seeding rates suggested here are excessive for most varieties grown on normal soils. Also, solid seeding or drilling soybeans, even though it is a good management practice in other soils, is not suggested in high pH or alkaline soils where chlorosis is a problem.