Influences of nitrogen, phosphorus, potassium and boron combined application on the nectar production of oilseed rape (Brassica campestris L.)

Regression method of orthogonal rotation combination with 4 factors and 5 levels was employed to study the influences of N, P, K and B combined application on nectar production of oilseed rape. Among the factors influencing oilseed rape nectar production, application rates of N, P, K, B were chosen as the variants for decision–making in production, and nectar production was adopted as the target function. The data obtained was analyzed with the computer and quadratic regression model was established. Analysis of the main effect and reciprocal effects of the model showed that the rates of P, K were the main dominate factors influencing the nectar production. The optimal fertilization rate for high nectar production was recommended as N 150 kg, P2O5 126 kg, K2O 157.5 kg and H3BO3 7.5 kg per hectare in our study condition. The results provide the basis for the optimal combination in fertilization practice for the purpose of high nectar production.