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1 Decrease of seedling emergence According to the test, 30 mesh insect nets are used to cover in the high temperature season in summer, and the rhizosphere temperature of the crops in the greenhouse will be significantly increased. Generally, the daily average ground temperature is 4~5°C higher than the exposed ground. If the ground temperature is too high, the seed germination rate will be reduced. , The following measures can be taken to prevent and control the production.
1 Select good varieties with good heat resistance, such as Yangyan 40, Ningjing 3, etc. can be selected in this area.
2 Before the broadcast, ground water should be used to reduce the temperature in the shed as much as possible. After the sowing, the cover soil should be deep, reaching 2cm, and the cover soil is too shallow. The surface soil is easy to dry and the seeds are not easy to germinate.
2 The plant is easy to grow and use the insect net to cover the cultivation, the plant internodes lengthen, the stem leaves are light, there is a phenomenon of leggy, and the flowering and seedling period is slightly later than the cowpea planted in the same period. Prevention measures are as follows.
1 Select the insect net, the mesh should not be too dense, generally should choose 18 to 22 purpose insect net, not only to prevent pest intrusion, but also improve the permeability performance, reduce the temperature and humidity within the network as much as possible.
2 In fertilizer and water management, the basal fertilizer must be fully applied, 3,000kg of organic fertilizer should be applied per 667m2, and 30kg of high-efficiency ternary compound fertilizer should be used. Apply N fertilizer as little as possible during vegetative growth and topdressing P during reproductive growth. K fertilizer, combined with the application of multi-functional foliar fertilizer.
3 To properly reduce the sowing density, according to the test, cowpea net planting density should be reduced by 5% to 10% compared to exposed land, the appropriate spacing between rows is 80cm, small row spacing 60cm, plant spacing 25cm, broadcast 3500 to 4000 per 667m2 hole.
3 Insect repellent effects are susceptible to insect repellent effects are susceptible to many factors, in order to make the insect repellent effect is significant, we must pay attention to the following points.
1 Coverage time To ensure that the whole growth period of cowpeas in the summer and autumn is produced in the net room, cover the net before the arrival of plum rain in early June, and it must not be too late, otherwise it is difficult to control pests after pests invade and lay eggs.
2 Soil treatment must be carried out before the cover. Before the cover is covered, it is necessary to deepen the cornice, clean the canopy, and treat it with chemicals on the ground. Generally, spray the panacea with 8% of 48% Lactose per 667 square meters to kill. Pests that remain in the soil.
3 Strengthen the management of the net room During the production of the net room, the net room must be sealed, the net foot pressure should be compacted, and the top pressure line should be tight to prevent the strong wind from being lifted in the summer. Usually go in and out of the shed to close the door, so as to prevent the moths from flying into the shed to lay eggs. At the same time, we must always inspect the insect nets for holes and gaps, and if they are repaired in time, ensure that no pests invade during growth.
4 Use of silver-gray mesh can effectively avoid individual smaller aphids.
4 The disease is slightly heavier due to the use of insect nets. The evaporation of water in the net is small, and the air circulation in the net is poor. After the rain, it may easily lead to higher humidity in the shed for a longer period of time. Therefore, the disease is more prone to damage than in open areas. Prevention measures are as follows.
1 First, the deep sorghum planting method should be adopted in the shed. The sulcus must be as deep as 30 cm. Secondly, there should be a good drainage system outside the shed so as to effectively eliminate the water in the field and reduce the temperature and humidity of the plant roots.
2 rational use of chemicals. Diseases mainly include rust and mycoplasmosis. Rust is treated with 20% triadimefon 2000 times spray, and mycoplasma is sprayed with 70% mancozeb 500 to 700 times or 70% thiophanate-methyl 1000 times. Note that the maximum number of doses for each drug is 2 and the safety interval is 7 days or more.
Common problems and prevention measures in the cultivation of summer and autumn cowpea insect nets
Kidney beans are one of the main vegetable cultivars in summer and autumn. However, due to the serious occurrence of pests such as bean pods, Spodoptera litura, and spotted fly, the use of general chemical pesticides to prevent and control will not only increase the resistance of insect pests, but also cause excessive pesticide residue. Therefore, since 2001, the city has begun to promote the use of insecticide nets to cover the cultivation of summer and autumn cowpea, to achieve no (minor) pesticide cultivation. However, some problems have also arisen in promoting the use of insect nets. It is hoped that farmers' friends will pay attention when they are cultivated, and take corresponding management measures to overcome them when planting.