Foliar Fertilization as a Strategy to Increase the Proportion of Mature Pods in Peanut (Arachis hypogaea L.)

Foliar application of nutrients is used by growers to remediate crop nutrient deficiencies, but anecdotal reports indicate there may be associated effects of accelerated crop maturity, particularly for irrigated peanut (Arachis hypogaea L.). Research was conducted to determine whether application of foliar fertilizers during early pod set could increase the proportion of early-maturing pods, and thereby increase the mature proportion of the profile under irrigated conditions. Field experiments were conducted in Florida at Citra in 2016, Jay in 2016 and 2017with a randomized complete block with four foliar fertilizer treatments, applied to GA-06G at R1 and again two wks later at R2. Treatments consisted of no foliar fertilizer (control), 10.0 kg N/ha, 1.0 kg P2O5/ha, and 0.34 kg B/ha at each application and two harvest timings. Harvest treatments were based on the adjusted growing degree d model for peanut and were timed to represent early and optimal crop maturity. Leaf tissue nutrient concentrations were determined from samples collected 24h after each foliar treatment application. Yield and proportion of mature pods were quantified after each digging date. Normalized difference vegetation index data showed no treatment differences. The maturity profile (percentage of mature pods present in the sample) was not consistently different from respective controls during either harvest period. Results indicate foliar fertilizer applied during flowering had little effect on maturity acceleration in peanut, though foliar fertilization may still be effective at alleviating in-season nutrient deficiencies. Within site-year, application of foliar fertilizer did not increase yield. Under sound soil fertility management programs, foliar fertilizers did not increase yield or the maturity profile of peanut.