Mineral Sources of Potassium for Plant Nutrition

D.A.C. Manning Abstract Recently published assessments of nutrient budgets on a national basis have shown that K deficits for developing countries are so substantial that a doubling of world production of potash fertilisers would be required to balance inputs and offtake, simply to meet demands in Africa alone. The price of potassium fertiliser raw materials has increased by a factor of 4 during 2007–2009, approaching $1000 per tonne in some markets. Thus an annual investment of the order of US$5600 million is required to replenish soil K stocks in Africa. In this context it is appropriate to review current knowledge of alternative sources of ...

Performance evaluation of phonolite through mineral form and enrichment of filter cake in sugarcane ratoon

In order to evaluate the performance of phonolite as a source of potassium in fertilization management of sugarcane ratoon through mineral and organo-mineral forms, an experiment was installed in November of 2011 in Casa Branca, SP, Brazil, in soil type red-yellow Latosol Dystrophic medium texture, with variety SP 801816, in third yield, harvested mechanically with no fire. The experiment was designed using random blocks with four replications. The treatments were: T1-Control; T2- Mineral Phonolite 8.5% dose 70 kg ha-1 of K2O; T3- Mineral Phonolite 8.5% dose 100 kg ha-1 of K2O; T4- Mineral Phonolite 8.5% dose 130 kg ha-1 of K2O; T5- Mineral Phonolite ...