Site Specific Nutrient Management for Corn in El Salvador
Extensive areas of crop land are cultivated with corn El Salvador, but average yields are low. Production of corn grain is utilized to satisfy dietary needs of the population, but there is also an increasing demand for corn grain to be used as animal feed. From the stand point of human and animal feed, this crop is strategic for the country. In the past, conditions like the opening of global markets and low yields made corn production unattractive because corn grain could be imported at cheaper price than the grain produced locally. However, unforeseen conditions in the global market have improved substantially international corn prices and corn grain production became profitable and essential for the country.
Corn production in El Salvador phases several limitations which explain the low productivity. The more important are declining soil fertility and inappropriate use of the new hybrids with high yielding potential. Work conducted in the last four years in different countries of the region has demonstrated that yields can be improved significantly with the use of technology, particularly higher plant population and adequate nutrient management to take advantage of the new hybrids potential.
Fertilizer recommendations used in the different corn producing areas of the region do not satisfy the nutrient needs for high yielding corn. Most of these recommendations are based on soil test calibration work conducted many years ago with different corn germplasm. In many cases, one general fertilizer recommendation is used for extensive areas of production, assuming that nutrient needs are constant in time and space. Improvement of corn production in El Salvador needs a more dynamic approach in terms of nutrient management.
A site specific nutrient management approach, based on the omission plot technique, was developed to study the influence of local agro-ecological conditions on nutrient requirements as a tool to develop fertilizer recommendations to achieve high sustainable yields.
1. Determine yield potential, yield goals and yield gaps for the new corn hybrids at the different agro-ecological sites in El Salvador.
2. Build up a set of practical tools for site specific nutrient management.
3. Develop simplified fertilizer recommendations for the most representative agro-ecological zones of the corn growing areas of El Salvador to obtain high sustainable yields.