Urea uses five methods in agricultural production

　　 Urea is an organic compound composed of carbon, nitrogen, oxygen and hydrogen, also known as urea (same as urine). Its chemical formula is CON2H4 , ( NH2 ) 2CO or CN2H4O , and the international generic drug name is Carbamide . The appearance is white crystal or powder. It is a product of animal protein metabolism and is commonly used as a nitrogen fertilizer for plants.

In addition to topdressing, urea has many other new uses.

First, adjust the amount of flowers

In order to overcome the size of apples, in the small years, 5~6 weeks after flowering (the critical period of apple flower bud differentiation, the growth of new shoots is slow or stopped, the nitrogen content of leaves shows a downward trend). 0.5% urea aqueous solution is sprayed on the leaves. Even spraying 2 times can increase the nitrogen content of the leaves, accelerate the growth of new shoots and inhibit the flower bud differentiation, so that the flowering amount of the new year is appropriate.

Second, sparse flowers and thin fruit

The flower organs of peach trees are sensitive to urea but the reaction of kneading is slow. Therefore, the use of urea to test the peach and nectarines in foreign countries has shown that the peach and nectarines need to be concentrated. ( 7.4% ) can show good results, the most suitable concentration is 8~12% , and within 1~2 weeks after spraying, the purpose of thinning and thinning can be achieved. However, under different land conditions, the response of different periods and different varieties needs further testing.

Third, rice seed production

In the hybrid rice seed production technology, in order to increase the parental rate of heterosexuality, in order to increase the amount of hybrid rice seed production or the number of sterile lines, the erythropotox is used to reduce the degree of maternal neck or Completely withdraw; or spray parental, adjust the growth of both, so that the flowering period is synchronized. Because of the relatively high price of gibberellin, the cost of seed production is high. People used urea instead of gibberellin for experiments. 1.5-2% urea was used at the booting stage and at the beginning of the earing stage ( 20% heading) . The breeding effect was similar to that of gibberellin and did not increase the plant height.

Fourth, pest control

4:1:400 parts of urea, washing powder and water can be mixed to prevent pests such as aphids, red spiders and cabbage caterpillars on fruit trees, vegetables and cotton, and the insecticidal effect is over 90% .

Five, urea iron fertilizer

Urea forms chelated iron with Fe2+ in the form of a complex . This organic iron fertilizer has a low cost and is effective in preventing iron deficiency and chlorosis. In addition , 0.3% urea was added to the foliar spray of 0.3% ferrous sulfate, and the effect of controlling chlorosis was better than that of single-spraying 0.3% ferrous sulfate.

Urea is an organic compound composed of carbon, nitrogen, oxygen and hydrogen, also known as urea (same as urine). Its chemical formula is CON2H4 , ( NH2 ) 2CO or CN2H4O , and the international generic drug name is Carbamide . The appearance is white crystal or powder. It is a product of animal protein metabolism and is commonly used as a nitrogen fertilizer for plants.

In addition to topdressing, urea has many other new uses.

First, adjust the amount of flowers

In order to overcome the size of apples, in the small years, 5~6 weeks after flowering (the critical period of apple flower bud differentiation, the growth of new shoots is slow or stopped, the nitrogen content of leaves shows a downward trend). 0.5% urea aqueous solution is sprayed on the leaves. Even spraying 2 times can increase the nitrogen content of the leaves, accelerate the growth of new shoots and inhibit the flower bud differentiation, so that the flowering amount of the new year is appropriate.

Second, sparse flowers and thin fruit

The flower organs of peach trees are sensitive to urea but the reaction of kneading is slow. Therefore, the use of urea to test the peach and nectarines in foreign countries has shown that the peach and nectarines need to be concentrated. ( 7.4% ) can show good results, the most suitable concentration is 8~12% , and within 1~2 weeks after spraying, the purpose of thinning and thinning can be achieved. However, under different land conditions, the response of different periods and different varieties needs further testing.

Third, rice seed production

In the hybrid rice seed production technology, in order to increase the parental rate of heterosexuality, in order to increase the amount of hybrid rice seed production or the number of sterile lines, the erythropotox is used to reduce the degree of maternal neck or Completely withdraw; or spray parental, adjust the growth of both, so that the flowering period is synchronized. Because of the relatively high price of gibberellin, the cost of seed production is high. People used urea instead of gibberellin for experiments. 1.5-2% urea was used at the booting stage and at the beginning of the earing stage ( 20% heading) . The breeding effect was similar to that of gibberellin and did not increase the plant height.

Fourth, pest control

4:1:400 parts of urea, washing powder and water can be mixed to prevent pests such as aphids, red spiders and cabbage caterpillars on fruit trees, vegetables and cotton, and the insecticidal effect is over 90% .

Five, urea iron fertilizer

Urea forms chelated iron with Fe2+ in the form of a complex . This organic iron fertilizer has a low cost and is effective in preventing iron deficiency and chlorosis. In addition , 0.3% urea was added to the foliar spray of 0.3% ferrous sulfate, and the effect of controlling chlorosis was better than that of single-spraying 0.3% ferrous sulfate.