When growing vegetables in a greenhouse, if there are continuous rainy days, one of the remedial measures should be to appropriately lower the temperature of the greenhouse during the day and night to maintain crop yields.

Photosynthesis must be carried out under light, so the intensity of photosynthesis increases with the increase of light intensity within a certain range; the respiration of plants is affected by temperature, concentration of oxygen and carbon dioxide, light intensity, etc. Within a certain range, low temperature can inhibit the respiration of plants and reduce the consumption of organic matter in plants. Therefore, when vegetable farmers grow greenhouse vegetables, appropriately increasing the light during the day can enhance photosynthesis, and appropriately lowering the temperature at night can weaken the plants. The respiration reduces the consumption of organic matter, thereby increasing the accumulation of organic matter and increasing the yield of vegetables.

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