Effect of Calcium and Irrigation Treatments on Peanut Yield, Grade and Seed Quality¹

The effect of irrigation and/or Ca (calcium) application on yield, grade and seed quality was studied using Florigiant peanuts planted on three dates. Calcium application resulted in a small, but consistent, yield increase at all planting dates. Irrigation resulted in a large yield response on early planted peanuts and no response on late planted ones. Grade, specifically sound mature kernel percentage, was improved by both Ca and irrigation treatments but the effects were only slightly additive. Similar interaction effects were noted as these treatments increased the germination percentage of the seed produced and decreased the percentage of kernels with the form of damage termed dark plumule. Both treatments also decreased the amount of watery hypocotyl damage and increased the Ca concentration in the seed. Germination was 89 to 94% when the seed Ca level was greater than 420 ppm, but fell linearly to 52% when the seed Ca decreased from 420 to 200 ppm.