Fertilization with potash is still uncommon in many regions. "Potash" refers to all potassium fertilizers: the most commonly used is potassium chloride (KCl) or muriate of potash (MOP), followed by potassium sulfate (K2SO4 or SOP) and potassium nitrate (KNO3 or NOP). With potassium discovered more than 200 years ago by English chemist, Sir Humphry Davy, in 1807; the theory of mineral nutrition in place since 1830 (Carl Sprengel, 1787-1859); and thousands of published research papers and a multitude of potassium products, why is it that, according to various indicators, K use is lagging in many areas?
There is no simple answer. Unlike nitrogen and phosphorous - at low crop yield levels, soil available K may be sufficient for the crop although it will not help to mitigate biotic and abiotic stresses. However, there is a great risk that soils become depleted of indigenous K and, in the long-term, yields decline further. Other on-farm inputs also contain potassium: K in irrigation water (e.g. in North India) and K in crop residues are the most common "sources" of these types of K fertilization. When preparing a fertilization program, these sources should be taken into account.
Having a quick, cost-effective, online and large-scale measurement for analyzing plant’s K status would make recommendations easier and more applicable. Until such technology is made available, there is no alternative to the well-known and reliable soil and plant analysis, from which an accurate fertilizer recommendation can be derived. However, we have been pleased to learn of an exciting initiative developed by IRRI scientists to improve decision-making for N, P and K recommendations: The Nutrient Manager for rice is a decision support system (DSS), which assists farmers to define the fertilization required based on data from his own specific plot. With the DSS available for use on the web or on smart phones, the application has the potential to be used by large numbers of farmers who have yet to make site-specific adapted decisions. Developments, such as Nutrient Manager on mobile phones and other new initiatives should help to close the gap and promote more effective use of K (and other nutrients) application.
In this issue, we also feature research papers on potato production in the State of Bihar, India, K fertilization of sugarcane in Bangladesh, variable rate application of potash for soybean in Brazil as well as updates of events and new scientific publications.
Finally, we are pleased to report that IPI has completed the development of various social media tools. Our Twitter page is kept up to date with the latest news from the IPI website, other websites and sources. Our newly designed Facebook page has an application (app) to display IPI's projects in the regions, and the latest tweets and re-tweets from our Twitter page. These are designed to improve the visibility of our activities and to make them more easily available to Facebook and Twitter users.
