Cotton is one of the important cash crops in our city. The scientific and technical personnel of the Municipal Agriculture Bureau gave the following suggestions on cotton planting management technology: ① Apply base fertilizer and sow. (1) One of the raw materials for photosynthesis is carbon dioxide. By applying farmyard manure or ammonium bicarbonate or burning charcoal in the greenhouse, the concentration of carbon dioxide in the greenhouse can be increased, so that the raw materials for photosynthesis are sufficient, thus enhancing the intensity of photosynthesis and increasing the yield of vegetables.

(2) Cotton should be covered with plastic film when sowing to maintain the temperature required for seed germination.

(3) Adding different fertilizers in different growth stages to ensure the normal growth of cotton shows that plants need inorganic salts.

(4) Photosynthesis of green plants is a process in which green plants use light energy to convert carbon dioxide and water into organic matter for storing energy and releasing oxygen, and the place where photosynthesis takes place is chloroplast; In order to increase the yield of crops, we must make full use of light energy, reasonable close planting and intercropping as important measures, make full use of light energy, increase the effective area of photosynthesis, and rationally close plant the same crop, and the leaves of the same crop have the same status quo, so that the leaves of plants are arranged in mosaic form. With reasonable close planting, plants can receive sunlight for photosynthesis to the maximum extent and synthesize more organic matter, which can increase the yield. Moreover, intercropping can accept different degrees of sunlight, more organic matter and increase yield.

(6) The phenomenon that apical growth is dominant is called apical dominance. Principle: The auxin formed by the terminal bud is transported downward, which increases the concentration of auxin near the lateral bud and is inhibited because the lateral bud is sensitive to auxin. At the same time, the top with high auxin content took away the nutrition of the lateral buds, resulting in insufficient nutrition of the lateral buds. The principle of apical dominance is widely used in fruit tree pruning. Artificial removal of apical buds can promote the generation of lateral buds and increase the number of branches. In production practice, pruning of fruit trees, tea trees and cotton tops is often carried out according to the principle of top dominance, so as to increase branches and increase yield.

(7) At the maturity of cotton and peach, the water absorbed by plants is mainly used for transpiration. Plants absorb water from soil through roots, and only about 65,438+0% of the absorbed water is used by plants as raw materials for photosynthesis, and about 99% is discharged into the atmosphere in the form of water vapor through transpiration of green plants. This is not a waste of water, and the transpiration of green plants has its positive significance.

So the answer is: (1) Organic matter in farm manure is decomposed by microorganisms in the soil to produce carbon dioxide;

(2) (appropriate) temperature; ? (3) Inorganic salts are needed for plant growth; (4) Make full use of light to improve the efficiency of photosynthesis;

(5) Increasing the oxygen content in soil and promoting root respiration; ? (6) Topping cotton to increase branches and yield; (7) transpiration;