INTEGRATION BETWEEN SOIL AND FOLIAR APPLICATION OF PHOSPHORUS AND POTASSIUM ON THE PRODUCTIVITY OF SOME PEANUT CULTIVARS

Two field experiments were conducted during the two successive seasons 2017 and 2018 on a private farm at El-Gazar village, Sadat City, Menoufia governorate, Egypt (latitude 30◦ 27'39'' N, longitude 30◦40'23'' E). The presented study aimed to study the response of some introduced and local peanut cultivars (NC 9, Gregory, Giza 6, and Ismailia1) to integrate different levels of phosphorus and potassium fertilizers applied by soil and foliar application. Soil application of phosphorus (15, 30, and 45 kg P2O5 fed-1) and potassium (24, 36, and 48 K2O fed-1) were applied either individually or mixed. Foliar application of P was applied as phosphoric acid at the rate of 2 ml-liter-1, whereas K was applied as potassium sulfate at the rate of 3 g liter-1. The nodulation and yield of the tested cultivars varied significantly across the two growing seasons. The forming of root nodules and their weight were increased by NC 9 cultivar followed by the Giza 6 cultivar. NC 9 cultivar was significantly superior to the other tested peanut cultivars for yield characters except for 100-seed weight and harvest index which was recorded by Giza 6 and Ismailia1, respectively. Giza 6 shared superiority with NC 9 without significant differences between them in the number and weight of seeds pod-1 traits. However, Gregory cv. was significantly inferior to the other cultivars in both seasons. It can be noticed that the highest rates of P and K either separately or their combination produced nodulation and yielded characters with the lowest rates of them and unfertilized plants which recorded the lowest values. The highest nodulation as well as yield and its components characters were registered by fertilized plants with 30 kg P2O5 + 36 kg K2O + one Spray with 2 ml phosphoric acid + 3 g potassium sulfate/L or by 45 kg P2O5 + 48 kg K2O + 0 spray without significant between them for all characters studied. In most of the traits examined in this study, the interactions between cultivars and fertilization systems were found to be significant. Fertilized NC 9 or Giza 6 plants with 30 kg P2O5 + 36 kg K2O + one spray with 2 ml phosphoric acid + 3 g potassium sulfate/L was the most effective treatment for increasing seed and pods yields per feddan compared to the other tested treatments and saved phosphate and potash fertilizers by 33.33% under the conditions of this experiment.