1. Early-maturing and middle-maturing varieties are selected for early rice and late-maturing varieties for late rice; Hybrid rice with long growth period, fertilizer tolerance, high yield and disease and insect resistance should be selected for middle rice. Wide and narrow row transplanting of rice on ridge surface. The fertilization ratio is 70-80% of base fertilizer and 20-30% of topdressing. Fertilization method: base fertilizer is generally applied to the ridge surface, and covered with soil when ridging; Urea should be used for topdressing, and ammonium chloride, ammonium bicarbonate and ammonia water are prohibited to avoid fish poisoning. When topdressing, the fertilizer must not be directly sprinkled in the fish ditch or fish pond to avoid hurting the fish. Choose low toxicity and high efficiency pesticides, and do not use herbicides and highly toxic pesticides. If Nile tilapia is stocked, it is forbidden to use rice blast nets. Before applying the pesticide, deepen the water layer in the paddy field of the ridge by 5 ~ 6 cm, spray powder in the morning and emulsion at night, and do not spray the pesticide directly in the fry or fish ditch.

2. Double cropping rice areas should be resistant to high temperature, pests and diseases, and damp; Rapid growth and reproduction, high photosynthetic nitrogen fixation efficiency. Spiraea tenuifolia and Kazhouping were mixed in the middle rice area, and Spiraea tenuifolia was the main species in the early stage. In the later period, it was mainly in Kazhouping. The ping release time is usually 5 ~ 7 days after the early and middle rice turn green. It is necessary to pay attention to the combination of multiple duckweed species and feed fish in fertile fields, especially to choose duckweed varieties with high temperature resistance, such as Sophora japonica, Qingping and Miping. Bait for some fish can be supplied from July to September. Fertilization and Pingping can promote high yield in Pingping.

3. The fish species should be those who like to eat Manjianghong, gain weight quickly, have good meat quality, tolerate hypoxia and adapt to the rice field environment. For example, grass carp, Nile tilapia, hibiscus carp, Xiang crucian carp and bream are selected in Hunan. If the fish species are released every other year, they will be released about 7 days after transplanting early rice; If summer flower fry are stocked, they can be released at the end of May and the beginning of June. And do a good job of "five defenses": escape prevention, flood control, heatstroke prevention, virus prevention (pesticides, fertilizers), and enemy prevention (water snakes, waterfowl, voles).