Paddy or rice is one of the most important crops grown worldwide. In order to obtain a good yield, proper management of nutrients is essential. Fertilizer management is one of the major components of proper nutrient management in the paddy crop.
The key to a successful paddy crop is the application of fertilizers at the right time, in the right amount, and in the right manner. There are different techniques used for fertilizer management in the paddy crop, and top dressing is one of them.
Top dressing is the practice of applying fertilizer to the soil surface, in between crop rows, after the crop has emerged. It is a technique used to supply the nutrients that are not available in the soil or have been depleted due to previous crop growth. The following are some aspects of top dressing fertilizer management in the paddy crop:
1. Time of application: The timing of top dressing is critical for a good yield. The first top dressing should be applied between 20-30 days after transplanting (DAT) in the case of transplanting and between 30-40 DAT in the case of direct seeding. The second top dressing should be applied between 45-50 DAT in both transplanting and direct seeding.
2. Amount of application: The amount of fertilizer to be applied depends on the soil fertility status, crop stage, and crop requirement. A general guideline for the application of nitrogen (N) fertilizer is 50 kg N/ha for the first top dressing and 30 kg N/ha for the second top dressing. However, the amount of N, phosphorus (P), and potassium (K) should be determined based on soil test reports and crop requirement.
3. Fertilizer placement: Fertilizer should be placed in between the crop rows or in furrows made by mechanical means or manually. The placement should be at least 5-7 cm away from the rice plant’s main stem to avoid root burning.
4. Mixing with soil: The top dressing fertilizer should be mixed with the soil to avoid runoff and leaching losses. The soil should be lightly irrigated immediately after the fertilizer application to enhance nutrient uptake.
5. Fertilizer type: Different types of fertilizers can be used for top dressing, such as urea, ammonium sulfate, and calcium ammonium nitrate. Urea is the most common and readily available form of N fertilizer for top dressing.
In conclusion, top dressing fertilizer management in the paddy crop is essential for good crop growth and yield. A proper understanding of the fertilizer requirements of the crop and the use of appropriate management practices can lead to successful top dressing of fertilizers in the paddy crop.