Determination of the effect of boron application on boron nutrition, yield and quality parameters in peanut in field conditions

Micronutrients play a significant role in increasing the yield of leguminous and oilseed crops. Among these, boron (B) is an essential micronutrient that contributes to cell division as well as pod and seed development. This study was carried out in 2024 to determine the effects of different B doses and application methods on B nutrition, yield, and selected yield parameters in peanut (Arachis hypogaea L.). The experiment was carried out in the Hacıali Farm of the Eastern Mediterranean Agricultural Research Institute, located in the Yüreğir district of Adana Province, Türkiye. The field trial was designed according to a randomized complete block design in factorial arrangement with four replications. The peanut cultivar "Ayşehanım" was used as the plant material. Boron treatments were applied as follows: Control (only N and P fertilizers applied to the soil), Soil B application (1, 2, 4, and 8 kg ha⁻¹ of Etidot-67 applied once at planting along with basal fertilizers), Foliar B application (300 mg L⁻¹ of Etidot-67 solution applied twice using a backpack sprayer—at flowering and fifteen days later), and Combined soil + foliar B application (1, 2, 4, and 8 kg ha⁻¹ of Etidot-67 applied to the soil once, plus 300 mg L⁻¹ foliar spray applied twice as described). The results showed that B applications influenced plant performance with pod weight per plant ranging from 46.7 to 81.3 g, pod number per plant from 24.1 to 37.0, 100-seed weight from 102.5 to 117.5 g, proportion of grade I pods from 56.22% to 67.35%, grade II pods from 31.43% to 40.80%, shelling percentage from 69.4% to 72.0%, seed yield from 315.8 to 437.0 kg ha⁻¹, protein content from 21.64% to 27.45%, oil content from 46.0% to 48.8%, seed B concentration from 34.2 to 47.9 mg kg⁻¹, and B concentration in shoot from 17.08 to 20.93 mg kg⁻¹. Among the treatments, foliar application of 300 g ha⁻¹ B and soil application of 2 or 4 kg ha⁻¹ B were found to be the most effective in improving yield and yield-related parameters. Consequently, it is concluded that under Çukurova conditions, the combined application of B via both soil and foliar methods within the same growing season may serve as an effective strategy to prevent yield and quality losses caused by B deficiency. Keywords: Boron, Peanut (Arachis hypogaea L.), Oil and Protein Ratio, Yield