Hey rice farmers! Did you know that the type of rice fertilizer you use, as is the case in Mwea, can increase or lower your production capacity by more than 35%?. Other factors that can affect your production capacity include irrigation, disease and crop management.
Irrigation is important because it ensures that the nutrients applied in form of fertilizer, is taken up by the crop and are not lost to leaching, volatilization, denitrification, or immobilization.
Rice Fertilizer Nutrient Requirements
Before applying any fertilizer, you must first assess the soil condition of your field through semiannual or annual soil testing. After conducting a soil analysis, seek advice from a licensed agronomist who will guide you on what the soil requires.
All macro-and micronutrients are required for growth; however, nitrogen and potassium are the nutrients that rice requires the most. Nitrogen influences all yield-related parameters (e.g., spikelet number per panicle, percentage of filled spikelets, grain protein content), so a sufficient N supply is required to achieve high yields. in addition, N deficiency is the most frequently detected nutrient deficiency in rice.
Phosphorus is important during the early stages of development (for tillering). When the root system of the rice plant is not fully developed, a phosphorus-based fertilizer should be added to the plant. It increases the photosynthetic rate, which leads to higher yields.
Potassium (K) ensures high rice yields. It makes rice disease-resistant, increases the size of the root, thickness, and promotes leaf development.
Rice Field and Soil Preparation
To increase your rice yields, everything must be done correctly from the start. Rice fields are prepared using two main methods:
- Wet preparation method
- Dry preparation method
The wet preparation method is suitable for use in low and high upland fields. It requires a large amount of water to prepare because the soil is tilled in waterlogged conditions. Dry preparation, on the other hand, does not require the land to be tilled in waterlogged conditions.
There are two methods of planting rice:
- Transplanting method
- Direct Seeding method
On average, you will require (100 – 160 kg) of seeds per hectare. For some varieties, you may require (220-250 kg) of seeds per hectare. Before direct seeding begins, the seeds are usually incubated for 1-2 days. They are then planted in a straight line, leaving a space of 6 to 10 inches (15-25 cm) between them. The water is then allowed to fill the field either immediately or 8-12 days after direct seeding.
If you are transplanting rice, prepare your seedbed in an area that is around 2-10% of the area to be transplanted. For example, if our field is 10 hectares (100.000 square meters), our seedbed should be at least 0.2 hectares in size. You require approximately (700 kg) of seeds per hectare though this can vary depending on the variety being planted.
Rice should be sowed in lines that are 2 to 4 inches apart. After we’ve finished sowing, let the water fill the seedbed to a depth of 2 inches. From 15 to 40 days, rice plants should be kept in the nursery (depending on the variety in question). When the plants reach a height of 8 – 12 inches, they should be ready for transplanting.
Fertilizer Deficiency in Rice
If there is a potassium deficiency in rice, you will notice that the leaves are dark green. Also, older leaves will show signs of wilt and turn brown. In other varieties, the leaves may develop red and purple tints. Potassium deficiency can be caused by several factors one of them being sandy soils and planting rice in a land that has low organic matter.
Phosphorus is important because it promotes
- Early crop development
- A strong root system
- Uniform crop development
Rice that is deficient in calcium may show signs of yellowing and withering. They may also have split or rolled tips, as well as discolouration. Older leaves might also start to sag. Deficiency symptoms usually appear first on young leaves, followed by shorter, dark brown roots. Calcium deficiency can impair root function and lead to iron deficiency.
Calcium helps ensure that the foliage is healthy
Nitrogen deficiency is a condition in which plants lack nitrogen. As a result, old leaves begin to yellow and then succumb to light brown necrosis, beginning at the tip. Plants without sufficient nitrogen tend to mature slowly, increasing the cost of production.
Rice requires a lot of nitrogen. Most nitrogen is required between mid tillering and panicle initiation stages. Nitrogen is important because;
- It ensures that the foliage is in good condition
- Helps in Photosynthesis
- Increases the quality of the leaves