Application of fertilizers on castor plants (the results of VNIIMK, review)

The researches conducted in the V.S. Pustovoit All-Russian Research Institute of Oil Crops showed that castor plant yield increased by 0.08-0.20 t/ha after fertilizers application on leached chernozem. The more effective dose of a primary fertilizer under castor is N40P60, which applied in autumn separately under the plowing. Higher doses of the fertilizers are less effective. Application of potassium fertilizers jointly with nitrogen-phosphorus ones in both typical (K40-45) and increased (K80-120) doses did not caused the yield increase of castor plant. Under application of the different doses of the nitrogen-phosphorous or full mineral fertilizers, oil content in castor seeds did not change significantly comparing with unfertilized control, and oil yield was determined by seed yield and increased by 0.06-0.09 t/ha. The local application of N20P30 during castor plant sowing proved the same level of yield comparing with the dose N40P60 - 1.73-1.74 t/ha. The local application of fertilizers during sowing is the most effective when placing the fertilizers strips in a distance of 2 cm sideways of the seeds. Against the backfilling into the soil of 6.2-6.6 t/ha of winter wheat residues, the application of mineral fertilizers under castor plant caused the increase of seed yield by 0.21-0.29 t/ha, oil yield - by 0.11-0.14 t/ha. The dependence of castor plant yield on nitrate nitrogen, mobile forms of phosphorous, and exchangeable potassium contents the in leached chernozem in spring was revealed. It is determined the castor plant does not react positively on the additional fertilizer application when contents of mobile forms of phosphates and exchangeable potassium in a soil layer of 0-20 cm are equal to 26-28 mg/100 g (in the hood by Chirikov F.V.) and 31-32 mg/100 g (in the hood by Maslova A.L.), respectively, and content of nitrate nitrogen in a soil layer of 0-60 cm is more 17-18 mg/kg (by Grandval-Lyazhu).