How to grow tobacco to withstand drought?

How to grow tobacco to withstand drought? Tobacco has higher requirements for water in the growing period, and the yield and quality of tobacco leaves will be significantly affected by drought stress. China is a country with shortage of water resources, and the temporal and spatial distribution of water resources is uneven. In recent years, some tobacco areas in China have suffered from severe drought, the frequency and scope of drought have expanded, and the duration and losses have increased. It has a great impact on tobacco production in China. Through the construction of water conservancy facilities irrigation to solve the drought problem of tobacco in the growing season, although it has a good effect, but the cost is too high, it is difficult to achieve matching irrigation in all tobacco fields in a short time, and it is not desirable in some tobacco areas. Therefore, at present, it is still the main way to take relevant agronomic measures to improve the water demand of tobacco growth. Pay attention to the selection of varieties in tobacco areas suffering from severe drought should focus on the selection of drought-resistant varieties such as Yunyan 87 and K346. It is worth noting that when selecting drought-resistant varieties, various localities should comprehensively consider them according to their local ecological conditions and other factors. The soil with good soil management in tobacco field has the effect of storing water and preserving soil moisture, heat preservation and fertilizer increase, but in recent years, with the expansion of tobacco planting scale, more and more inorganic fertilizers are applied, coupled with improper planting systems and methods, resulting in the decline of soil fertility in tobacco fields. the phenomenon of soil consolidation is becoming more and more serious. Therefore, how to improve the ability of soil water storage and soil moisture conservation is an important link for us to develop drought-resistant cultivation techniques of tobacco. Improving soil ① gradually increases the application amount of organic fertilizer and reduces the use of inorganic fertilizer. At present, there are more and more researches on organic fertilizer in improving soil properties. According to the research results, the main effect of organic fertilizer in soil improvement is to improve soil aggregate structure and porosity. And reduce its bulk density. It can not only improve the soil water retention and air permeability, but also increase the content of nitrogen, phosphorus and organic matter in the soil. ② planting suitable varieties of green manure or economic green manure, and timely turn over green manure. In recent years, green manure planting has been vigorously promoted in some areas of Chongqing, and good results have been achieved. Optimizing tobacco field preparation scheme is an important measure to improve soil condition, which can significantly improve soil physical properties and plough layer structure, improve soil fertility and prevent soil-borne diseases and insect pests. The way of soil preparation and its quality directly or indirectly affect the growth and development of tobacco and the yield and quality of tobacco leaves. Therefore, we should do a good job in the soil preparation of tobacco fields: ① grasps the cultivated land period of tobacco fields, which is greatly influenced by the climate characteristics, soil characteristics and previous crops of the main producing areas. Generally speaking, in dry farming tobacco areas, the period of cultivated land is generally before harvest and destroy stubble farmland as early as possible. in addition, when determining the period of cultivated land, it is also necessary to determine the period of cultivated land according to the ploughness of the soil, such as poor structure or high clay content, heavy texture and difficult to cultivate tobacco fields. it is necessary to plough early and promote soil granulation or agglomeration by freezing, melting and alternating between dry and wet. ② generally thinks that deep ploughing is better than shallow ploughing to grasp the depth of cultivated land. According to the research of the Institute of Chinese Academy of Agricultural Sciences, proper deep ploughing is beneficial to the growth of tobacco root system. Under the same conditions, the distribution range of tobacco root system and the root amount of tobacco increase with the increase of cultivated land depth, and the root system is well developed. the root system activity is strong, so as to improve the absorption capacity of tobacco roots to nutrients and water. Therefore, tobacco fields are generally ploughed to a depth of 20cm to 30cm, and should be ploughed deeply every 2-3 years to break the bottom of the plough. In addition, the ploughing depth can be increased appropriately in tobacco fields with lower fertility, but not too deep in tobacco fields with higher fertility. Transplanting strong seedlings refers to tobacco seedlings with good growth and development, normal metabolism, more synthesis and accumulation of organic matter, rich contents, coordinated ratio of carbon to nitrogen, strong stress resistance and high survival rate of transplanting. On the basis of this, Henan Agricultural University put forward the characteristics of floating and strong seedlings of flue-cured tobacco: the seedling age is 60-70 days, the root system is developed, the number of roots is more than 300, the number of leaves per plant is 7-9, the stem height is 8-16 cm, the stem circumference is 1.5-2.1%, the root dry weight is more than 0.05 g, and the aboveground dry weight is more than 0.46 g. By transplanting strong seedlings, the utilization of irrigated water of tobacco seedlings can be improved, and the soil moisture of tillage layer can be used as early as possible after transplanting, so as to enhance the drought resistance of tobacco plants. to a certain extent, it can reduce the adverse effects on the growth and development of tobacco plants in the early stage of field growth due to lack of natural precipitation in dry farming areas. Improving cultivation techniques of tobacco cultivation techniques are determined according to the production of high quality tobacco leaves with different quality characteristics and the indexes of yield and quality. Its purpose is to coordinate the relationship between tobacco growth and development and environmental conditions, and the relationship between groups and individuals. Tobacco cultivation techniques cover a lot of contents, including transplanting, water and fertilizer management, cultivation control techniques and so on. The cultivation techniques of tobacco under drought conditions should also be improved on this basis. 1. First of all, according to the local precipitation law, determine an optimal transplanting period, so that the law of tobacco water demand is consistent with the law of precipitation, so that precipitation can be effectively used to avoid the drought period. Secondly, ridge planting was adopted when transplanting, the ridge cultivation was covered by thick loose soil layer, and the soil water, fertilizer, gas and heat conditions were improved, which was beneficial to the growth of tobacco roots and aboveground parts. Finally, the tobacco seedlings with strong and developed roots should be selected when transplanting, and the method of watering and transplanting should be adopted. two。 There are two main mulching methods, plastic film mulching and straw mulching. Mulch cultivation plays a very important role in drought-resistant cultivation of tobacco. Mulching cultivation can improve the temperature and water condition of soil and near ground, increase soil temperature, maintain soil moisture, improve soil properties, improve soil nutrient supply and fertilizer use efficiency. 3. Improved fertilization technology ① base fertilizer is mainly organic fertilizer, phosphate fertilizer and potassium fertilizer are all used as base fertilizer, 80% of nitrogen fertilizer is used as base fertilizer, and the rest is applied in time according to soil moisture. ② fertilization at the bottom of autumn combined with the last autumn ploughing, the bottom fertilizer (including organic fertilizer and chemical fertilizer) was applied to the farmland. The suitable depth of fertilization is 20cm to 25cm. ③ application of high-quality organic fertilizer farm manure should be more than 37500 kg / ha, promote no (or less) soil manure compost and straw washer fertilizer. 4. Timely ploughing and soil cultivation can play the role of loosening soil, storing water and preserving soil moisture, regulating soil moisture and promoting the growth of tobacco root system. In areas with arid climate, tobacco fields with poor irrigation conditions should adopt the methods of early ploughing, fine ploughing and high soil cultivation in order to prevent drought and resist drought. 5. Proper use of ① paclobutrazol can reduce the synthesis of endogenous hormones, inhibit the dominance and cell elongation of top tobacco seedlings, promote a large number of root growth, enhance leaf stomatal impedance, reduce transpiration intensity of tobacco seedlings, and significantly enhance drought resistance. ② fulvic acid tobacco experiment showed that FA could increase leaf water potential and relative water content, reduce stomatal conductance and transpiration rate, reduce evapotranspiration, enhance root activity, and effectively reduce the damage caused by drought stress, which has a good effect on improving drought resistance of tobacco plants. FA treatment improved the drought resistance of tobacco plants, and FA root irrigation treatment of 100ml was the most effective, followed by 200mm foliar spraying. In addition, there are some growth regulators that can enhance the drought resistance of tobacco plants, such as growth retarder dwarf, abscisic acid and so on. Click to get more tobacco planting techniques click to get more flower planting techniques