After rice transplantation, around three days later, the seedlings start to grow and their tips begin to exude water. On sunny days, the leaves of young seedlings open up, and new roots develop, marking the "greening" stage. At this critical period, field management should focus on several key aspects.
First, it's essential to inspect the seedlings and fill in any gaps to maintain proper density and ensure a sufficient number of healthy plants. Second, irrigation must be carefully managed. The rice is particularly sensitive to moisture during this phase because the root system is still recovering from transplanting, and its ability to absorb water is reduced. If there's not enough water, the seedlings may struggle to green up or even die. Conversely, too much water can also hinder the greening process. Third, applying nitrogen-based fertilizer shortly after transplanting—usually 2 to 3 days later—helps promote early growth of new leaves and tillers, resulting in stronger seedlings. When applying fertilizer, keep the water level shallow, about 3 cm deep.
Weed control is another important aspect. Weeds grow quickly and compete with rice for water, nutrients, and sunlight, which can negatively impact rice growth. Common weeds include grasses, sedges, and broadleaf species like dwarf arrowhead, bamboo vegetables, and others. To manage these effectively, farmers often use chemical herbicides.
There are various types of herbicides available. Here are some commonly used options:
1. **Herbicides mixed with soil or fertilizer**
- 125% refined Grass Star: 25–35 grams per mu, applied 5–9 days after transplanting.
- 220% Glutinous Rice: 30–45 grams per mu, applied 5–12 days after transplanting.
- 15.6% Kunming No. 2: 50 grams per mu, applied 3–7 days after transplanting.
- 20% Kunqi: 150 grams per mu, applied 10–25 days after transplanting.
- 50% Paraquat: 80–100 grams per acre, applied 10 days after transplanting (after seedlings have turned green).
- 50% Butachlor: 150–200 grams per acre, applied 5–7 days after transplanting.
- 10% DuPont New Effective: 10 grams per mu, applied 7–10 days after transplanting. These can be mixed with 20–25 kg of soil or fertilizer and applied evenly either in the morning after dew or after 4 PM.
2. **Direct application herbicides**
- 9% Lazy Han: 45–60 grams per mu, applied 4–7 days after transplanting.
- 30% Yunnan Tianmao: 40–60 grams per acre, applied 3–5 days after transplanting. Apply in the morning after the leaves dry or after 4 PM.
3. **Herbicides applied after weed emergence**
- 50% Scorpion Herbicide: 25 grams at the two-leaf stage, plus 5 grams of yam if needed. Spray 30 kg of water evenly. Irrigate with 3–5 cm of water 2 days after application and maintain it for 5–6 days.
- 10% DuPont New Effective: 10 grams per acre for 2–3 leaf weeds, sprayed evenly in 25 kg of water. For specific weeds like dental grass, spray when the leaves turn from red to green. Drain the field and re-flood 2 days after application, maintaining a 3–4 cm water layer for 5–7 days.
By following these practices, farmers can significantly improve the health and yield of their rice crops while effectively managing weeds.
Guangzhou Fuerle Health Technology Co., Ltd , https://www.fuerlegroup.com