At present, it is in a hot and rainy season. High temperatures, heavy rain, tropical cyclones and hot thunderstorms often hit agricultural crops, especially for early rice and vegetables. (1) High temperature: The harm caused by high temperature on the growth and development of crops is called high temperature heat damage. Early rice in Guangdong Province is often affected by high temperatures during flowering to filling period, which increases leaf temperature, reduces photosynthesis of leaves, increases plant respiration rate, and reduces the supply of materials, resulting in an increase in the rate of alfalfa and shortening the filling period. Thousand-grain weight dropped, causing a reduction in production. In order to reduce or avoid the threat of high temperature and heat damage, in addition to selecting high-temperature resistant varieties, adjusting the sowing and planting period, and making rice sensitive to high-temperature damage avoid high temperature weather, the following defenses can also be adopted when the high temperature comes or comes. Measures: 1 Water management: In the later period of rice, shallow water should be used for irrigation, night irrigation should be done, and dryness should be done at a proper time to prevent water cut off prematurely, so as to improve the microclimate of paddy fields, promote strong root systems, and enhance the ability to resist high temperatures. Deepening the water layer during the daytime at high temperature can reduce the spike temperature by 1-2°C. When the high temperature is combined with drought, it can reduce the body temperature and increase the temperature between the plants. Day irrigation night row can increase the temperature difference between day and night, the effect is better. According to the experiment, if the temperature difference between day and night increases by 1°C, the weight of grains can increase by 0.5-1 g. 2 Sprinkler irrigation: Sprinkler irrigation can significantly reduce the temperature and humidity. After the sprinkler irrigation, the field temperature can be reduced by more than 2°C, the relative humidity is increased by 10%-20%, and the effective time is about two hours. Sprinkling irrigation can reduce the emptying rate by 2-6% and increase the grain weight by 0.8-1 g. The time is appropriate before and after flowering. 3 spraying chemical agents: per acre with potassium dihydrogen phosphate 0.1 kg watered foliar spray; or when high temperatures occur when spraying 50ppm of vitamin C or 3% superphosphate solution, have the effect of reducing high temperature damage. (2) Heavy rain: When the early rice grouting period occurs, when there is a frontal trough torrential rain or a tropical cyclone torrential rain, in addition to causing flooding of rice fields, there are also lodging, falling grains, grain sprouting, mildew, serious diseases and insect pests, etc., resulting in yield and rice decline in quality. Rain defense measures: 1 Before the rain occurs, such as the early maturing of rice should organize the power to use time to rescue, so as to avoid damage caused by rain. 2 When there is continuous heavy rain to heavy rain, when there is accumulated water, the rice leaves should be exposed as early as possible so that photosynthesis can be carried out as soon as possible; when the rain falls, it is necessary to timely clean the sludge on the leaves; if the water recedes Immediately when it is clear, it is not possible to drain the water immediately and it is necessary to replace the fresh water slowly so as to prevent the water balance of the plants from being imbalanced and the leaves to wither. 3 After the rice grows, the foliar fertilizer should be sprayed properly to promote growth. 4 Rice pests are prone to various pests after flooding and must be comprehensively controlled.