Increasing Efficiency of Applied Fertiliser Phosphate Using Tools of Source, Dose and Method of Application: World Phosphate Institute, Morocco Experience at Farmer'S Fields in India.
G. Dev, Consultant in India, World Phosphate Institute, 129 D, Kitchlu Nagar, Civil Lines, Ludhiana, India and A. Nassir, World Phosphate Institute, Casablanca, Morocco.
Phosphorus (P) is an essential major nutrient element needed for crops. It performs many important functions in crop growth. The utilization of applied fertilizer P by crops is rather low, ranging from 20 to 25 % only and hence efficiency of applied P is rated as low This efficiency can be improved by selecting proper P source, dose based on soil P status and time and method of application. A great deal of research information is available suggesting that these are critical factors effecting efficiency of applied fertilizer P. Soils with low P status need relatively higher input of fertilizer P than medium to high P status soils. Like-wise, Water Soluble P (WSP) source when drilled in alkaline calcareous soils is more efficient over broadcast method. Further, citrate soluble P source when broadcast in acid soils is more efficient. However, farmers in general have not fully adopted these practices. This study reports the results of a large number of single replicated demonstration trials conducted at farmers' fields in different states of India involving various crops under a project: On-farm trials on efficient use of fertilizer P in balanced nutrition of crops, as supported by World Phosphate Institute, Morocco. The 3 to 4 plots treatments were selected based on the objective of the demonstration. The results clearly showed that rationalization of fertilizer P dose based on P status of the soils was critical in determining its efficiency. Soils with low P status needed relatively higher input of fertilizer P (125% of locally recommended dose). Reduction in fertilizer P dose to 75 % of locally recommended dose in medium or high P status soils resulted in its low efficiency. Drilling of WSP in low P status alkaline calcareous soils produced more crop yield over broadcast method, while this difference was less pronounced in soil testing medium to high in P status. Broadcasting of citrate soluble P source was more efficient in acid soils. The parameters used to evaluate the efficiency of applied fertilizer P were yield, response, % response and biological efficiency. Field days were organized at the demonstration sites to show the actual standing crops to the farmers of the area with the hope that they adopt these efficient practices for fertilizer P use in crops in their day to day agriculture to obtain high yields and more profit.