Sesame is a shallow root crop, and a loose soil environment is required during the growth process, especially at the seedling stage. Sesame grows very slowly before the third pair of true leaves, and the variety of weeds grows fast. It competes with sesame for fertilizer, water, and light, and it also makes sesame pests and diseases worse. If the weeds are not removed in time, causing grass shortage, it will affect the growth and development of sesame seeds and even abandon them. Weeding and weeding through cultivating can not only eliminate grass waste, but also play the role of loosening soil, ventilating and protecting. Improve growth conditions and promote early onset of seedlings. According to the survey, weeding and weeding 5 times from the first pair of true leaves, which increased the yield by 9.42% compared with the third pair of true leaves.
In addition to weeding, cultivating has many functions: increasing soil aeration, so that the sesame has a strong respiration, and its absorption capacity is enhanced, thereby growing lush. Increasing the effective nutrient content of the soil, soil microbes are active due to sufficient oxygen, and a large amount of potential nutrients are decomposed and released, which improves the utilization of soil nutrients. Adjust the soil moisture content, reduce the soil moisture transport to the soil surface and evaporate and lose, and improve the soil's drought resistance. Increasing the soil temperature, especially in the early spring, cultivating the soil with tight weight, the effect is more obvious, the seed can be germinated, and the seedlings are long and long. Control the absorption of nutrients and suppress the length of the child. It can also integrate soil and fertilizer, eliminate harmful substances in the soil and prevent denitrification, promote the occurrence of new roots and improve absorption capacity.
After applying the chemical herbicide, the cultivating time should be carried out 15 to 25 days after spraying, otherwise the chemical weeding effect will be affected. In addition, weeding in weeding should also pay attention to:
1. The period and frequency of cultivating and weeding are generally determined by the weather, soil moisture and seedling conditions at that time. Before the sesame seed is released, it is usually cultivated and weeded 3 to 4 times. In the first pair of true leaves and the second and third pairs of true leaves, the cultivating and weeding were performed once, and the third cultivating and weeding were performed when the branches were exposed.
2. The depth of cultivating and cultivating weeding should adhere to the principle of “light-deep-shallowâ€. That is, when the first pair of true leaves of sesame seedlings appears, the first cultivating is carried out. At this time, the seedlings are small, the roots are small, and the soil is shallow, and only shallow soil is needed to prevent the soil from being poured into the soil. The second cultivating was carried out in 2~3 pairs of true leaves. At this time, the root growth has reached a certain depth (about 20 cm), and the cultivating loose soil can be deepened to 6-7 cm. It can be slightly shallow when dry, and slightly deeper when the soil moisture is slightly larger. The third cultivating is carried out when the seedlings have 4 to 5 pairs of true leaves. At this time, it is already in the axillary outcrop, the flower buds begin to differentiate, and the root growth requires a thick layer of loose soil, the depth of the cultivating is 7~10 cm, and combined with the cultivating seedlings.
In the beginning flowering period, the sesame roots are deep and widely distributed, and there are many weeds or soils with heavy soil. In order to avoid the roots and the rainy soil, the soil is shallow, and only the grass is scraped off. After the sesame is closed, stop cultivating.
3. The cultivating and weeding should be “two nos†and “two mustsâ€, that is, before the rain, it will not be smashed, so as to avoid the rain after the sputum; the ground is too dry and wet, so as not to hurt the roots. In order to eliminate weeds and keep the soil loose, it is necessary to have grass, and it will be necessary after the rain.
4. Three-above cultivating and weeding three bogey roots around 6~7 cm deep roots, easy to onset; two taboos are not flat, easy to stain water; three taboos are not clear, the rain is not smooth.
(Wang Dixuan)
Ningbo Kyson Cool Electronic Technology Co., Ltd. , https://www.zjkysoncool.com