Institution:Board of Regents of the University System of Georgia on behalf of the University of Georgia Cooperative Extension Service and University of Georgia Research Foundation, Inc.
Region:Southeast (GA, FL, AL)
Project Fiscal Year:2014
Report Received Date:
Project NPB Budget:$32,000
Supplying calcium to the pegging zone of peanuts to 1) maintain high yields by avoiding pops, 2) maintain high quality in terms of grade and 3) maintain high germination rates for when saved for seed, continues to be the emphasis of soil fertility on peanut. Gypsum at bloomtime and lime at planting are the traditional ways of fertilizing peanut with calcium. The main objective of this project was to compare two new calcium materials to both lime and gypsum. "Topflow" is a very finely ground liquid lime normally used in the paper industry but is thought to have potential in the Ag market. Rate (5 or 10 gal/a) and placement (10 gal broadcasted vs 5 gal/a banded) of the Topflow was investigated. Polyhalite is another new fertilizer material that contains 16 % calcium (half of which is "pure gypsum") so it also has potential for peanuts. Calcium chloride through the pivot at peak pod fill under irrigation and at planting on dryland were also investigated. Overall, results from 4 location in 2014 (three irrigated and one dryland) indicate that lime at planting or gypsum at bloomtime are still the best recommendations for supplying calcium to the pegging zone of a peanut. The best response to calcium treatments was at the dryland site (there were little differences observed in the irrigated sites) with the current recommendations of lime at planting or gypsum at bloomtime being the best options. Polyhalite did increase calcium in the nut but not as high as these recommended treatments. Topflow at 10 gala broadcast at planting did an adequate job of getting calcium into the peanuts and was better than 5 gal/a banded which was also adequate but 5 gal/a broadcast was inadequate. Also, 10 gal/a of calcium chloride broadcast at planting was insufficient in terms of supply calcium to the developing peanuts.