High-yield cultivation techniques of Zizania caduciflora

Zizania caduciflora is a temperature-loving plant, which propagates asexually by tillers and tillers. It is suitable for growth at a temperature of 10-25 ℃ and is not resistant to cold, high temperature and drought. The frost-free period in the cultivated area is more than 150 days, and its leaves die after frost, and it can withstand a low temperature of-10 ℃ in dormant period. The frost-free period in northern China is short, mainly planting single-season Zizania latifolia, which is suitable for spring. In the south, the frost-free period is long, and both single-season and double-season Zizania latifolia are suitable for planting.

Zizania caduciflora is a crop that is not tolerant to continuous cropping, and rotation plays a very important role in the production of Zizania caduciflora. The yield of Zizania caduciflora introduced in some places is higher in the first two or three years, and the market is also early, but then the yield decreases year by year, the market period is delayed, the pods become smaller and the quality declines. in addition to the problems in seed selection, the tillage system is also one of the main factors.

Types of rotation

The rotation of Zizania caduciflora field includes different crop rotation of paddy field and rotation of flood and drought. Paddy field rotation is mainly the rotation of Zizania caduciflora with rice, mat grass, water lotus root, water chestnut, mushroom and other crops. In the rotation of Zizania latifolia and rice, Zizania latifolia adopts double-cropping Zizania latifolia varieties, ploughing and raking soil preparation immediately after summer harvest, applying sufficient base fertilizer, planting single-cropping rice or even late japonica rice, the two cropping periods are complementary, and high yield can be obtained. Zizania caduciflora and mat grass rotation in single season or double season Zizania caduciflora was harvested in autumn for soil preparation, fertilization and planting mat grass. The rotation of water and drought in Zizania caduciflora field is mainly with the rotation of fruits and vegetables in dry land, which mainly include: autumn Zizania latifolia-summer Zizania latifolia-summer and autumn cabbage-eggplant fruits-overwintering greenhouse-autumn Zizania latifolia, autumn Zizania latifolia-summer Zizania latifolia-summer cabbage or radish-autumn winter cabbage-spring Kandelia Candel fruits-autumn Zizania latifolia and so on. These rotation methods are all in autumn, and after summer, they are changed to dryland vegetables. Flood-upland rotation can effectively improve the physical and chemical properties of soil, which is the best way to solve the obstacle factors of crop continuous cropping.

Zizania caduciflora farmers in Huangyan, Zhejiang Province also adopted a method of border and ditch exchange, that is, planting Zizania caduciflora in the same field, changing the ditch of the previous year's Zizania latifolia field into a border, and changing the border of the Zizania caduciflora field into a ditch every year. This method also has a certain effect of rotation and plays a certain role in overcoming the obstacles of continuous cropping. In this way, combined with other fertilizer and water management measures, Zizania caduciflora was continuously planted in some local fields in Huangyan for nearly ten years, and there was no obvious reduction in yield and quality.

Yield-increasing mechanism of flood-drought rotation

Some Zizania caduciflora farmers are lack of understanding of the role of Zizania caduciflora field rotation, often adopt continuous cropping for many years, and some even transplant and harvest for several years, seriously affecting the yield and quality of Zizania caduciflora. According to the investigation, the continuous cropping of Zizania caduciflora has more than two production cycles, and the output of each cycle is reduced by 10-15%. The reasons for increasing the yield of flood-drought rotation are as follows:

1. It can obviously improve the physical and chemical properties of soil, especially reduce the bulk density of soil, increase the aeration and permeability of soil, and improve the aggregate structure of soil. it plays a very good role in the release of soil nutrients and the absorption and utilization of nutrients by crops.

2. It can reduce crop diseases. Sheath blight and flax leaf spot increased significantly after continuous cropping of Zizania caduciflora. The longer the continuous cropping, the more serious the disease. After the rotation of flood and drought, the incidence rate was obviously reduced.

3. It can improve the utilization rate of fertilizer. In the soil of Zizania caduciflora continuous cropping, the consumption of phosphorus and potassium is high, and nitrogen can not play a full role. After the rotation of flood and drought, the soil fertility can be fully utilized and the fertilizer utilization efficiency can be improved.

4. It can reduce weeds in the field, the change of flood and drought ecological environment is not conducive to the continuous reproduction and growth of the same kind of weeds, and can obviously reduce the damage of weeds.

Interplanting and three-dimensional planting and breeding model

In addition to rotation, interplanting can also be carried out in Zizania caduciflora fields. The main intercropping crops in Zizania caduciflora field are rice, lotus root, water spinach and other aquatic crops. of course, they can also be interplanted with wheat, rape or dryland vegetables. The method of interplanting can be interplanting between rows or multiple rows, or interplanting around and in the middle of the field. The use of interplanting in Zizania latifolia field can effectively improve the utilization rate of land and improve the ventilation and light transmittance among plants.

In order to further improve the utilization rate and yield of Zizania caduciflora field, a three-dimensional ecological breeding model of symbiosis between Zizania caduciflora and field fish, green shrimp, rice field eel, crab and duck has emerged in recent years, and good benefits have been achieved.