On-farm trials of optimal fertilizer recommendations for the maintenance of high seed yields in winter oilseed rape (Brassica napus L.) production

Abstract

(2015) On-farm trials of optimal fertilizer recommendations for the maintenance of high seed yields in winter oilseed rape (Brassicanapus L.) production, Soil Science and Plant Nutrition, 61:3, 528-540, DOI: 10.1080/00380768.2014 ) on the rapeseed yield, and three indices of soil nutrient supply were adopted to estimate the yield responses to fertilizer recommendation. The results showed that the average contributions of nitrogen (N), phosphorus (P) and potassium (K) fertilizer to seed yield were 40.4, 23.1 and 11.5%, respectively. Compared with the farmers' fertilization practices (FFP), the recommended fertilization significantly enhanced the seed yield by 29.1% on average. The relationships between plant-available soil nutrient supply, seed yields of the nutrient omission treatments and the yield responses to fertilization were significant, rather than the results of soil testing. With plant-available soil nutrient supplies and seed yields increasing, the yield responses and fertilizer use efficiencies decreased. When the seed yields of no-N and no-P treatments were less than 2000 kg ha −1 and 1500 kg ha −1 , the recommended fertilizer rate was beneficial for achieving high seed yield and high efficiency. As defined in our study, the recommended fertilization rates could be used as the regional mean optimal rates (RMOR) of fertilization for winter oilseed rape in the Yangtze River Basin. Partial adjustments according to crop nutrient uptakes and seed yields of the nutrient omission treatments will be feasible for the sites where they were nonresponsive to RMOR.

Formula Fertilization Promotes Phoebe bournei Robust Seedling Cultivation

“…For Phoebe bournei seedlings, the application of N changed the biomass allocation among seedling parts, which appeared to be beneficial to leaf growth, while relatively limiting to stem and root growth. This same phenomenon is reported in other trials [26,44,46]. P fertilization rates were positively correlated with height and root collar diameter, indicating that P promoted seedling growth, thus it is beneficial to aboveground biomass accumulation.…”

“…The unique "3414" experimental design not only has the advantage of using less treatments and maximizing the efficiency of the design's optimal regression, but it also allowed for meeting the necessary requirements of fertilizer test and decision. This design is widely used in determining the fertilizer effect of grain, vegetables and other crops with remarkable success [25,26,28]. In the present study, the fertilizer application rates calculated by unitary, binary and ternary models were within the present experimental range.…”

“…The "3414" experiment design, as a complete three-factor test, has the advantages of an optimal regression design with less treatments and a higher efficiency, thereby creating regression equations of unitary, binary and ternary secondary fertilizer effect [25]. It is widely used in field experiments to determine the fertilizer effect on plant performance [26][27][28]. Trials examining the simultaneous response to multi-nutrient fertilization treatments can produce results that are difficult to predict due to nutrient interactions.…”

“…The "3414" fertilizer experimental design allows for the examination of multi-nutrient fertilization treatments, through the advantages of regression optimal design with less treatments and high efficiency. This approach can establish regression equations of fertilizer effects, it is more intuitive, allows for treatment comparability and is well suited for conducting multiple treatment field fertilization experiments [25][26][27][28]. The "3414" fertilizer experimental design was used to investigate N-P-K application rates and ratio effects on the growth of one-year-old Phoebe bournei seedlings.…”

Combined application of nitrogen and potassium reduces seed yield loss of oilseed rape caused by Sclerotinia stem rot disease

“…The optimal N application rate (180 kg ha −1 ) combined with a higher K application rate (120–180 kg ha −1 K 2 O) is a feasible nutrient management strategy for achieving high seed yield with lower SSR infection risk. To partly offset the negative effects of SSR, these N and K application rates were slightly higher than the regional mean optimal fertilizer application rates (Ren et al., 2015). Although further increases in the N application rate (180–270 kg ha −1 ) would still increase seed yield, the ANRE would decrease slightly and the SSR infection risk would also increase.…”