Growing vegetables in greenhouses: have you paid attention to carbon nutrition?

As we all know: carbon is the first of the six essential macronutrients for plants. Carbon accounts for 58% of the organic matter of crops and 30%~35% of dry matter. The photosynthesis of crops and the reproduction and metabolism of microorganisms all require a certain carbon source. When carbon is deficient, it causes an imbalance in the carbon-to-nitrogen ratio, which in turn affects the plant, the soil, and so on. So in vegetable cultivation, have you noticed the importance of carbon nutrition?

The fact: with excessive application of chemical fertilizers, carbon becomes the weak link

The carbon that crops need is mainly absorbed through the stomata of the leaves as carbon dioxide from the air, which is converted by the photosynthesis of chlorophyll into carbohydrates that make up the internal tissues of the crop. The roots of plants also directly absorb carbon dissolved in water from the organic matter in the soil, which is transported into the plant interior and, through electrochemical reactions of another nature, forms the plant's internal tissues, mainly cellulose, lignin, sugars, and so on. In the original ecological environment, the various plant species formed over billions of years have each developed a certain balanced and complementary ratio of obtaining carbon from the air and obtaining carbon from the soil.

But in actual production, especially when organic fertilizer is neglected and chemical fertilizers are applied excessively, this mechanism is destroyed. This gives rise to problems such as crop leaves becoming thinner, stems being hollow (with little dry matter), poor taste, susceptibility to disease, and premature aging of the plants. This also proves in turn that the absorption of carbon dioxide through crop stomata cannot replace the role of the roots in absorbing water-soluble carbon. And when the environment presents severe stress, for example continuous rainy weather, or abnormal temperatures (extremely cold or extremely hot), as well as in the case of plastic greenhouse cultivation, when crops cannot carry out normal photosynthesis, or need to support an extra large amount of energy, the role of the roots in absorbing water-soluble carbon becomes even more indispensable and irreplaceable.