Sweet Corn Cultivation Video _ Current Problems and High-yield Cultivation Methods of Sweet Corn

1. Problems 1. The quality of sweet corn needs to be improved. The breeding time of sweet corn in China is short. The investment in research strength and research funds is seriously insufficient. Due to the lack of reasonable resource exchange among various units and the breeding orientation of emphasizing yield and neglecting quality in China, the number of inbred lines selected is very limited and the edible quality is not ideal. Sugar content, crispness and seed coat thickness of sweet corn are mainly quantitative characters, but the existing domestic sweet corn hybrids have thicker skins. It tastes greasy and tender. It tastes terrible. Sugar decreased rapidly, the best harvest period was shorter, and the shelf life was shorter. The quality of sweet corn in China is generally poor, and there is a big gap with foreign countries.

2. Sweet corn germplasm resources are scarce.

China is not the origin center of sweet corn. Its breeding resources depend entirely on the introduction from abroad, which makes the breeding resources of sweet corn in China very scarce. At present, China's sweet corn breeding resources mainly come from the United States, and a small part from Thailand, with narrow blood relationship and single ecological type, especially the lack of high-quality, heat-resistant, cold-resistant and barren-tolerant sweet corn breeding resources, which seriously affects the further development of China's sweet corn breeding.

3. Super sweet corn breeding needs to be further strengthened.

In super sweet corn breeding, most genotypes of existing combinations or varieties are sh2 gene. However, the research and utilization of sh 1, sh4 gene and bt 1, bt2 gene are seldom or never utilized. Although imported varieties overcome some of the above shortcomings, the seeds are expensive and have poor resistance and adaptability.

4. Genetic basis of stenosis

At present, a large number of sweet corn varieties are being approved and promoted, and the good and the bad are mixed. Most of them are bred from common inbred lines to sweet corn inbred lines. Due to the lack of sufficient understanding of the source of the transferred materials. It caused the loss of some excellent characters, and the performance in production was basically the same. Although there is a certain yield basis, other traits such as quality cannot be fundamentally improved. There is no improvement in breeding.

Second, sweet corn cultivation techniques

1, variety selection and seed treatment

At present, there are Shennong Tiandan, Tiandan No.8, Jinxian 1, Jinxian No.2, Tianyu No.2, Tianyu No.4, Tianyu No.6, Zhongtian No.2, Tianke1/KLOC-0 and so on. Sweet corn has high sugar content, and its seeds are vulnerable to soil underground pests, resulting in seedling shortage. It is best to accelerate germination and sow. Choose plump and robust seeds, soak them in clear water for 24 hours, then soak them in 500 times solution of 50% carbendazim or 75% thiophanate-methyl for 2-3 hours, and then take them out and clean them. Control drying and accelerate germination. Put the seeds into a container covered with dry linen, spray a proper amount of hot water at 40 ~ 50℃ on the surface of the seeds, cover them with wet cloth, and sprout after 24 hours at 25 ~ 28℃. If the outside temperature is low, take measures to increase the temperature and promote seed germination. It is best to show white buds. It shouldn't be long.

2, timely sowing, reasonable close planting

Sweet corn is a vegetable crop. If it is harvested in the off-season, it can greatly improve the economic benefits. When the soil temperature is stable at 10 ~ 12%, the sowing amount is 22.5kg/hm2, and the artificial sowing amount is 15kg/hm2, which can reach the expected number of seedlings. Generally, small row spacing of 50cm, large row spacing of 70cm, average row spacing of 60cm and plant spacing of 30cm can achieve a seedling density of 55,500 plants /hm2 and a harvest of more than 52,500 ears /hm2.

3. Use fertilizer scientifically

The test results of surface soil nutrients in the introduction site are: organic matter 14.67g/kg, total nitrogen 1. 13g/kg, alkali-hydrolyzable nitrogen 8 1.9mg/kg, available phosphorus 48.5mg/kg and available potassium1kg. In terms of fertilization methods, one is to apply base fertilizer again and increase organic fertilizer. 30t/hm2 of decomposed pig manure, 225kg/hm2 of urea, 0/50kg/hm2 of diammonium phosphate and 0/50kg/hm2 of potassium sulfate were applied at the bottom. The second is to fertilize twice. Topdressing is mainly nitrogen fertilizer, with 7-8 leaves once before jointing stage and another time before heading stage about 10d. Topdressing urea 1.50kg/hm2 each time can promote strong stems, big ears and high yield.

4. Tian Tuan management

(1) Sow at regular intervals

4 ~ 5 seedlings and 6 ~ 7 seedlings.

(2) intertillage weeding, drought and waterlogging prevention

Intertillage weeding is generally carried out three times, and the principle of "shallow, deep and shallow" is mastered. For the first time, shallow intertillage was carried out when 4 ~ 5 leaves were used, generally 3 cm; The second deep intertillage was about 10cm at 7 ~ 8 leaves, and the third shallow intertillage was 3cm after jointing stage. Because of the short growth period of this variety, it is necessary to prevent drought and waterlogging during the whole growth period, and the normal growth of the plant can be ensured without squatting.

(3) Rake the extra ears in time.

Sweet corn branches (tillers) easily. In order to promote the main stem spike to grow into a big spike and improve the quality of goods, it is necessary to straighten it in time. The first time is when decentralized growth begins, and after 7 ~ 8 days, the right time is 1 time, with the principle of early removal, less removal and no damage to the main stem. In addition, when the ear of this variety is formed, it is easy to produce 2 ~ 3 ears per plant, so it is necessary to remove the redundant ear except the main ear in time, leaving the first ear per plant.

5, pest control

Sweet corn is vulnerable to corn borer, scarab, aphid, cotton bollworm, liriomyza sativae and other pests, and ear rot is prone to occur in the later stage. The pest control of sweet corn should focus on treatment, early treatment, small treatment and multi-treatment. Because sweet corn is a vegetable crop, it is necessary to highlight the pollution-free integrated control technology in its pest control. Pesticide control While doing well in various pollution-free agricultural production measures, we should strictly ban pesticides banned in pollution-free agricultural production. The underground pests at seedling stage are mainly cutworms and mole crickets. The control of cutworms should be controlled in the second instar of larvae, and 80% dichlorvos 17500 times solution can be sprayed along corn rows; The main pests at heart leaf stage and ear stage are corn borer and cotton bollworm. Pyrethroids can be used to control 1 ~ 2 times from small bell mouth stage to large bell mouth stage. In order to prevent residual poison, biological pesticides such as imidacloprid and abamectin should be used to control aphids and liriomyza sativae after pollination of sweet corn, chemical pesticides should not be used or used less, and no drugs should be used when the pests are light. To prevent and control diseases, chlorothalonil and thiophanate methyl 1 ~ 2 times can be used in the early stage of filling, and the land with mild disease can be prevented or not.

6, timely harvest

The harvest time of sweet corn is strict, and the sweetness and yield of early harvest can not meet the requirements; If harvested too late, corn seeds will shrink. Sweetness drops. The output has decreased. Therefore, harvesting is based on the fact that corn bracts are dry, bracts are white, and grains are full and golden yellow or orange. When harvesting, 8 ~ 10 bract leaves should be reserved to ensure the quality of fresh bracts and prolong the storage time.

(Author: 158307 Heilongjiang Kenfeng Seed Industry Co., Ltd. 851/branch)