Low temperature weather continues to affect

(1) After sowing in early spring, because the air temperature is still relatively low, covering the ground with plastic film can increase the soil temperature, keep the soil moisture and promote the early emergence of seedlings.

(2) The growth of plants needs photosynthesis, respiration and transpiration. The fruit-type carrots in vegetable base were affected by rainy weather during the root expansion period and waterlogged in the field for a long time. Because of lack of oxygen in the soil, carrots can't breathe normally.

(3) The growth of plants needs photosynthesis, respiration and transpiration. Due to the long-term influence of low temperature and rainy weather, the photosynthesis of rape seedlings is not strong and the growth is weak. Pollination can't be normal at flowering stage, which leads to low seed setting rate.

(4) In early spring, eggplant and pepper planted in greenhouse vegetable base grew poorly due to long-term rainy weather and insufficient light. Because the light is insufficient, artificial light sources can be used to increase the light intensity.

So the answer is: (1) temperature.

(2) hypoxia; breathe

(3) photosynthesis; Pollen ...

(4) Using artificial light source to increase the light intensity.