Improvement of Recommendations for Potash Fertilizer Use and Adjustment of Currently Used Soil Potassium Test Interpretation Classes in Intensive Cropping Systems

The project has the following goals: a) determine optimal potash fertilizer rates for major crops in crop rotation that have a high demand for potassium, b) evaluate the validity of currently used soil test potassium interpretation classes for proper assessment of plant potassium requirements, c) develop proposals to the Ministry of Agriculture on possible fine-tuning of current practice to develop K fertilizers recommendations and adjustment of currently used soil test potassium interpretation classes. Locations of field experiments - Lipetsk, Voronezh, Belgorod, and Rostov Oblasts (Russia). Soil types - Chernozem soils with medium and “increased” (higher than medium) content of routinely extracted potassium. Crops - sugar beet, grain maize, rapeseed, soybean.


05 Feb 2013

2012 Annual Interpretive Summary

During the last 15 years in Russia, both nutrient use (rates) and ratios have changed with a larger decline in the share of P and K fertilizers relative to N fertilizer. The adjustment of nutrient rates considering soil type, fertility status and crop management factors has, therefore, gained high priority for research experiments in current cropping systems. With long-term removal of K exceeding K inputs, negative K budgets are being observed in various agricultural zones of the country. Nevertheless, Russian agriculture has paid little attention to the optimization of K status in arable soils. Such an attitude towards K regime regulation in agricultural systems is largely due to the imperfect assessment of soil K fertility. Routine soil test K interpretation classes used in practical work to develop fertilizer K recommendations give some evaluation of soil K status. Unlike in some other countries, the current soil test K interpretation classes are not based on soil texture.

This new research project will focus on the optimization of K fertilizer rates in current intensive cropping systems that involve crops that respond well to K (e.g., sugar beet, maize, rape, and soybean) and on checking the measurement potential of routine soil test methods depending on the regional soil properties and adjusting the current interpretation classes based on results from short-term field experiments executed on large industrial farms located in Central Russia (Lipetskaya, Voronezhskaya, Belgorodskaya oblast) and South of Russia (Rostovskaya oblast). First results from this project are expected in December 2013. Russia-01