Breeding natural enemies to protect crops

Raising spiders, stink bugs, bees and then releasing them in the field to destroy harmful public species instead of using chemicals sprayed on fruits and vegetables, has been successfully tested in some places, including Hanoi vegetables growing area. .

A farmer in Dang Xa Cooperative (Gia Lam, Hanoi) said that this method takes more time than spraying chemicals but ensures cucumbers are clean, so if they work for a long time, they can sell more.

' Strangely, thrips are significantly reduced without spraying any chemicals ', instead of having to spray up to 13 times in each case to eliminate thrips, the melon is still tightened and twisted. He said.

In 2007, for the first time, farmers here were allowed to experiment with releasing predatory bugs into cucumber fields. As a result, the number of thrips is controlled, not exceeding the threshold of harm, yield is no less than previous crop.

According to calculations by scientists, the cost of using bugs to catch prey is not cheaper than using pesticides. If the cost of chemical chemicals sprayed for one acre of land is about VND 130,000, the cost of raising and releasing the natural enemies is about the same, but the initial effect is the same.

If this method is maintained, it is possible to create long-term natural enemies in nature, thereby reducing the cost of raising and releasing natural enemies.'The most important thing is that the grower is more secure because of his health and environment' . Professor Hung said.

Along with being acidic, prey spiders are also released to experiment in Thanh Tri, Hoang Mai and Dang Xa vegetable areas, Gia Lam, Hanoi. Red-eyed bees with simple farming techniques have been transferred to farmers of Thai Binh, Nam Dinh, Hung Yen, Dong Thap, Binh Duong and Nha Khe cotton growing area (Ninh Thuan) to kill stem borers. Initial results showed that the number of thrips and stem borers decreased equally to chemical spray.

Breeding natural enemies to protect crops

Ancient goose bugs feed on larvae to improve their wealth (Photo: VNN)

Raising natural enemies has long-term and safe effects, but this method has not been able to be deployed widely.

There are only a few cotton-growing areas in the South and red-eyed bees except stem borer. The reason is that farmers still keep the habit of spraying pesticides which bring immediate effect.'Just spraying chemicals back once, the enemy will drop out and die' - Professor Hung sighed.

Besides, in addition to red-eyed bees, people can feed themselves, spiders and stink bugs catch their prey due to more difficult farming techniques, and need a clue to provide mass production and supply them to people.

No unit dares to undertake this phase because, to turn the enemy into a trade item, it must invest in a large-scale production line, while not guaranteeing whether to sell it.

In this regard, Prof. Dr. Vu Quang Con, Chairman of Science Council Institute of Ecology & Biological Resources, Chairman of Vietnam Association of Insects, said that to implement this method, must implement synchronize on a large scale. If this field cannot be used by natural enemies, another field will spray pesticides.

The state should have subsidy policies for farmers when they use biological methods in agriculture; In addition, funding should be provided to scientists raising natural enemies and transferring them to farmers.

Also according to Prof. Dr. Vu Quang Con, the current trend of planting trees in greenhouses is very suitable for releasing natural enemies to destroy harmful species. However, this should not be considered as an alternative method, but it must be used in combination with other measures in the pest management system such as the use of less toxic drugs with pests or microbial spray, intercropping to create places. living for natural enemies, etc.