Integrated Control of Zizania latifolia Rhizoctonia

Zizania caduciflora is a unique aquatic vegetable in China. Only China and Vietnam grow Zizania caduciflora as a vegetable in the world. The ancients called Zizania latifolia "Zizania latifolia". Before the Tang Dynasty, Zizania caduciflora was cultivated as a food crop, and its seeds were called rice or carved Hu, which was one of the "six grains" (millet, sorghum, wheat and wild rice). Later, it was found that some Zizania latifolia did not heading because they were infected with smut fungus, and the plants had no symptoms of disease, and the stems continued to expand, gradually forming spindle-shaped fleshy stems, which is now edible Zizania latifolia. In this way, people use powdery mildew to prevent Zizania caduciflora from blooming and fruiting and propagate this malformed plant as a vegetable. It can be used as medicine.

Growth environment of Zizania caduciflora

Zizania caduciflora is a temperature-loving plant, which can grow at a suitable temperature of 10-25 ℃ and is not tolerant to cold, high temperature and drought. The double-season Zizania latifolia is planted in the plain area, which requires less sunshine and higher water and fertilizer conditions, and temperature is an important factor affecting the pregnancy of Zizania latifolia. Zizania caduciflora has developed root system and large water demand, which is suitable for clay loam or loam with sufficient water source, convenient irrigation, deep and soft soil, fertile soil, rich in organic matter and strong ability of water and fertilizer conservation.

Zizania caduciflora can be divided into two types: single season in autumn and double season in autumn and summer. Both of them were propagated separately. Zizania latifolia was planted from Qingming to Grain Rain in a single season in the Yangtze River Basin, and could be divided into spring and autumn in summer and autumn. It was planted before and after Grain Rain in spring and before and after the Beginning of Autumn in autumn.

Zizania caduciflora can be divided into four stages:

1) sprouting begins in March and April after spring, and the lowest temperature is more than 5 ℃, and the suitable temperature is 10-20 ℃.

2) during the tillering stage from late April to the end of August, each plant could have more than 20 tillers, and the optimum temperature was 20: 30 ℃.

3) in the stage of pregnancy, there was one pregnancy in double seasons from the first ten days of June to the last ten days of June, and another from late August to late September. In a single season, Zizania latifolia was pregnant from late August to early September, and the optimum temperature was 15-25 ℃, which was lower than 10 ℃ or higher than 30 ℃.

4) in the stage of growth stagnation and dormancy, the tiller and aboveground growth stopped when the temperature was below 15 ℃, the aboveground died below 5 ℃, and the underground overwintered in the soil.

Integrated control of sheath blight of Zizania caduciflora

What is sheath blight?

Sheath blight is a fungal disease caused by Rhizoctonia solani. It is one of the most common diseases of rice. Generally, early rice is heavier than late rice, which often causes grain not full, empty shell rate increase, serious can cause plant lodging and death. Common in rice, wheat, millet and other Gramineae plants.

Symptoms of sheath blight of Zizania caduciflora

Sheath blight of Zizania caduciflora is a common disease of Zizania caduciflora, and its harm tends to be aggravated year by year. It mainly harms leaves and leaf sheaths, forming water-stained, dark green to yellowish-brown moire spots. At high humidity, the disease produces sparse light brown mycelium, and then forms a small white sclerotia that gradually changes to yellowish brown.

Occurrence characteristics of sheath blight of Zizania caduciflora

The pathogen is Rhizoctonia. When it was 25: 32 ℃, it was beneficial to the disease in overcast and rainy days, and there were many sclerotia in the continuous cropping soil, so the disease was serious.

Integrated control of sheath blight of Zizania caduciflora:

① has carried out flood and drought rotation for more than 3 years.

② reasonable close planting, combined with farming and other agricultural operations, timely removal of lower diseased leaves, yellow leaves, improve ventilation and light transmission conditions.

③ should strengthen the management of fertilizer and water, apply sufficient base fertilizer, properly increase phosphorus and potassium fertilizer, avoid partial application of nitrogen fertilizer and long-term deep irrigation, and carry out the water slurry management principle of shallow before, middle sun and wet after according to the needs of promoting tillering, controlling ineffective tillering and promoting pregnancy of Zizania latifolia.

In the early stage of ④, spray 5% Tiananshui 400x liquid, or 50% methyl thiophanate or 50% carbendazim wettable powder 70000x liquid, 40% distemper wettable powder 800x liquid, 5% Jinggangmycin water conservancy 50~100ppm, pay attention to spray enough, spray 7500L of good liquid per mu, once every 10 days, a total of 2 times.