Influence of Prohexadione Calcium on Pod Yield and Pod Loss of Peanut

Excessive vegetative growth of peanut (Arachis hypogaea L.) can make digging and inverting operations less efficient. Reducing vine growth by applying a suitable plant growth regulator would be an efficient way to manage peanut vines. Pod yield, market grade factors, and gross economic value of peanut treated with prohexadione calcium (calcium salt of 3,5-dioxo-4 propionylcyclohexanecarboxylic acid) were evaluated at 19 sites in North Carolina during 1999 and 2000. Experiments were also conducted at two locations each during 1999 and 2000 to determine the effect of prohexadione Ca, digging date, and lifting (shaking peanut vines after digging to remove soil before combining) on combined yield, market grade factors, gross economic value, seed germination, and pod loss of the virginia market-type cultivar NC 12C. Prohexadione Ca at 140 g a.i. ha -1 , applied at 50% row closure and repeated 2 wk later, increased row visibility at harvest, pod yield by 310 kg ha -1 , and gross economic value of quota peanut by $223 ha -1 when pooled over 19 sites. Prohexadione Ca increased combined yield by 220 kg ha -1 and decreased percent pod loss by 4% regardless of digging date and lifting treatment compared with nontreated peanut. Prohexadione Ca did not affect maximum yield (sum of pods remaining in soil and on the soil surface and pods that were combined) or germination of peanut seed. These data suggest that increased combined yield noted following application of prohexadione Ca can be partially attributed to decreased pod loss.