Impact of Integration between soil application of phosphorus and foliar spraying of nano potassium, iron, and boron on the productivity and quality of peanuts

Abstract

A two-year field experiment was carried out to assess the impact of three levels of soil application of phosphorus (untreated control (P0), 55.8 (P1), and 93.0 (P2) kg phosphorus pentoxide (P2O5) ha-1) and foliar application of nano-fertilizer treatments (i.e., untreated control; 500 ppm nano potassium (K1); 1000 ppm nano potassium (K2); 50 ppm nano boron (B1); 100 ppm nano boron (B2); 75 ppm nano iron (Fe1); 150 ppm nano iron (Fe2)) on yield and quality parameters of peanuts. The results revealed significant differences among phosphorus fertilizers levels on yield, yield components, and quality parameters of peanuts, wherein the increasing rate of P to 93.0 kg P2O5 ha^-1 (P2) enhanced the number of pods plants^-1, number of branches plants^-1, seed index, pod yield, seed yield, protein yield, and oil yield compared to control (P0), during the 2020 and 2021 seasons. Likewise, peanut plants treated with nano boron at 100 ppm (B1) gave the highest number of pods plants^-1, while application of nano Fe at 75 ppm (Fe1) and 150 (Fe2) gave the highest number of branches plants^-1. On the other hand, the application of 1000 ppm nano potassium (K2) showed the highest values of seed index and pod, seed, protein, and oil yield. The combinations of P and nano K, B, and Fe fertilization displayed significant increases in the number of pods plants^-1, number of branches plants^-1, and seed index. The interaction between P2 and nano B2 recorded the highest number of pods plants^-1. In addition, the application of P2 with K2 recorded the highest values of seed index and pod and seed yield. Results also indicated that spraying with nano potassium of 1000 ppm (K2) increased the potassium uptake compared to other treatments in both seasons except for spraying with potassium 500 ppm (K1) in the second season. For the combinations, P1-K2, P2-K1, and P2-K2 were the best combined treatments with the highest value for potassium uptake in peanut seeds in both seasons along with P1-K1 and P1-Fe2 in the second season.