The summer tomato seedlings are in the hot season from May to July, which is not conducive to the growth of plants. The high temperature, drought and aphid hazards are important conditions for the occurrence of viral diseases and other diseases, accompanied by strong winds and heavy rains. Sudden attack, the seedling process is slightly more difficult than other tomatos, and a slight negligence will cause problems, so you should be proficient in the breeding techniques in the hot season. 1. Problems and solutions that are easy to occur during sowing 1.1 The soil panel slab joints are often caused by two reasons: First, the soil of the bed is not good; on the other hand, the bottom water is insufficient, the humus content is small, the structure is not loose, and the knot is easy to occur. Therefore, when preparing the bed soil, it is necessary to mix the compost and manure with a large amount of humus into the bed soil. In addition to the composition of the bed soil, the cover soil after sowing needs to add an appropriate amount of fine furnace slag to prevent the soil panel knot. Nutrient soil generally formulated way: each seedbed fill clean and free of disease Land Park, by 40% - 50% proportion of mature compost or manure incorporated, then mixed with 1 m3 Chuangtu superphosphate 1kg, ash 5- -10kg. In addition, pouring the sole water is also one of the measures to prevent the soil panel knot. If sufficient bottom water before sowing, pre-emergence after sowing not need to water. On the contrary, if the bottom water is too small, the bed surface is dry after sowing, and the watering is improper, which may cause the bed panel knot. Unless the bed soil is too dry and not poured, you can use a jug to pour some water, and avoid flooding before the seedlings. 1.2 irregular emergence: emergence irregular, one is the emergence of time inconsistency, the seedlings early in the morning and late out seedlings difference a few days. Have been unearthed seedlings must promptly thrown off the cover, increasing light, humidity and temperature decrease seedbed, to prevent excessive growth. Of non-excavated seedlings, the need to maintain high temperature and humidity, in order to promote emergence. In this way, there will be a loss in the management of the seedbed, and in the same seedbed, the size of the seedlings is inconsistent, and the temperature and humidity management is very difficult. In another case, the distribution of the seedlings is uneven in the whole seedbed, and in some places, the emergence of seedlings is excessive, causing crowding, and in some places, there are few emergences, resulting in waste of seedbeds. The reasons for the inconsistent emergence time are mainly the inconsistent seed maturity, some of the seeds that are not full, the germination potential is low, the emergence of seedlings is slow or due to the mixing of new seeds, the new seeds are germinated, the emergence is fast, the seeds of Chen are weak, the germination is slow, or because of the seeds. when germination temperature, humidity and air uneven, inconsistent degree of germination of each seed. In addition, the amount of soil cover is also the main reason for the inconsistent emergence time. The reason for the unevenness of seedling emergence in the same seedbed is that the seedbed is not flat, the humidity in the bed is inconsistent; the second is that the seeding technique is not closed, the seed is not evenly distributed; the third is that the environmental conditions in the bed are inconsistent, and the central temperature of the general seedbed high, early emergence, high survival rate, the opposite peripheral location emergence seedbed of late. To overcome the irregularity of emergence, according to the above reasons, the seeds with high germination rate and strong germination potential should be used. The bed soil should be leveled, the seeding should be uniform, and the measures of covering soil and covering should be as uniform as possible. 1.3 Seedling top shell unearthed: Seedling top shell is mainly caused by two reasons: First, the seed storage is too long, the seed shell is too hard; Second, the seed maturity is not enough, the vitality is low, and when the seedling is unearthed, it is unable to shell. Planting too thin bottom insufficient water or soil, seed emergence yet, topsoil has dried, dried seed coat stiff, often not smooth off; when planting, soil is too thin, or too light casing, pressure is too small, the seedlings will be hooded unearthed. Hooded measures to prevent emergence of seedlings are: selection of the year new species or 1--2a (years) Chen species, soil should not be too light, too thin, if found in time hulled seeds covered with a layer of fine soil. 2. Reasons and solutions for the occurrence of seedlings Leggy seedlings nursery is a symptom season high temperature most likely to occur. The characteristics of the long seedlings are: the stems are slender, the leaves are thin and light, the tissues are soft and the roots are small. The reasons for the occurrence of the length are: the temperature in the seedbed is too high, especially the night temperature is too high, the respiration of the seedlings is enhanced, the nutrients consumed are more, the nitrogen fertilizer is more, the water is more, the humidity is too large, and the light is insufficient. The main measures to prevent the growth of the seedlings are to increase the light and lower the temperature. When the seedlings are too dense, the seedlings and seedlings are timely carried out. If you find that there is a long seedling, you should take ventilation and cool down, control the watering, reduce the humidity, or use the concentration of 2000μl / l chlormequat or 30μl / l paclobutrazol spray, after 1 week, the seedling leaves are dark green, The stem is thick and the effect is very good. 3. Reasons and solutions for flashing seedlings, wind slipping seedlings and burning seedlings The summer tomato seedling process is from May to July, the temperature is high, the light intensity, especially the sunny day, the greenhouse in the greenhouse often exceeds 35 ° C, sometimes above 40 ° C. When the temperature of the shed exceeds 40 °C, it is easy to burn. Precautionary measures: Increase the ventilation volume or use the shade net to reduce the temperature. Once the seedlings occur, they can be combined with watering to quickly cool down, increase the soil moisture of the seedbed, and prevent the burning of the seedlings. In addition, as the age of the seedlings increases and the temperature gradually rises, the amount of ventilation is gradually increased. If the plastic shed is removed, the “sparkling seedlings†and “wind slipping seedlings†are easy to be used. 4. Seedling pests and control From May to June, the tomato seedbed was the most dangerous, followed by small tigers, golden worms, and aphids.è¼è›„ æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž æ¥å›ž 土壤 土壤 土壤 土壤 土壤 土壤 土壤Precautionary measures: Before sowing, the film should be sprayed with 90% crystal trichlorfon 800 times liquid and sauteed wheat bran into the surface of the bed soil to prevent it from happening. At the same time, after the emergence of the seedlings, it is necessary to regularly apply the trichlorfon poison bait to prevent underground pests from damaging the seedlings. On the other hand, we should pay close attention to the movement of the locusts. We should pull a strip of silver-gray plastic film around the seedbed to avoid mites. Once the aphid should be sprayed in time, it can be sprayed 2 to 3 times with 20% virus a500 times solution + imidacloprid 1000 times solution. Spraying the seedling bed, the weeds around the seedbed or the crop should be sprayed. This will reduce the transmission of drugs and prevent viral diseases. 5. Seedling disease and its prevention Tomato seedling diseases mainly include blight, stagnation and leaf mold. The main control measures are as follows: 1 The soil of the seedbed bed should be selected from disease-free large field soil and disinfected. 2 Seeds are sterilized before sowing. 3 appropriate dilution, and time seedlings, seedlings. Strengthen ventilation, reduce the humidity of the seedbed, when the humidity is too high, sprinkle the fine soil or the ash of the grass and ash. The whole seedling period should be properly controlled for watering. If the soil is too dry, it is better to use a small amount of water in the jug, not flooding, if the disease is found After planting, watering is strictly controlled. 4 disease plants should be promptly removed after the emergence, and combined with chemical control, can be sprayed 70% mancozeb 500--600 times liquid or "Nongkang 120" 500 times liquid + anti-drying 500--600 times liquid Or chlorothalonil, anti-virus cockroaches and other prevention and treatment. Gateway,Zigbee Smoke Detector,Photoelectric Smoke Detector,Smoke Sensor Guangdong Isafenest Co.,Ltd. , https://www.isfenest.com