Many hydroponic gardeners and consumers are concerned with the quality, purity and safety of the food they eat. With soils becoming tainted and water sources polluted, it is a valid concern. In the farming industry, use of pesticides and herbicides has grown for years as farmers have attempted to control the pests and weeds that challenge their crops.
With consumers demanding safer produce, there has recently been an active movement away from excessive pesticide use. One way to achieve this is by the use of Biological pest controls rather than chemical pest controls. Biological controls consist of insects, mites and micro-organisms which, as natural enemies, keep pests under control.
Many commercial hydroponic growers who produce their crops within a controlled environment greenhouse exclusively use biological controls for problem pests. When bringing biological controls or beneficial insects into the greenhouse a natural balance can be achieved. It is possible to control pests in an open field with biological means but it is not as effective as within a greenhouse or other closed environment.
Virtually all insects have a predator or enemy and that is what makes biological control work. There are insectaries (facilities that raise insects) throughout the US and Worldwide that breed and sell beneficial insects. Beneficials are shipped as eggs, larvae or adults and are usually sent overnight to the user who quickly distributes them to the problem areas.
A parasite is an insect that lays its eggs within the egg sack of another insect, displacing or consuming the eggs that were there. The Larvae that emerge from the egg sack are those of the parasite, not it’s victim.
One example is the Whitefly. Whitefly are an extreme problem for greenhouse growers, field and orchard crop farmers and home gardeners. The whitefly sucks large quantities of sap from the plant and secretes the sugars as honeydew. This makes the leaves sticky and susceptible to fungal growth and rot. In a serious infestation, the fungus and rot associated with the honeydew can kill an entire crop in a matter of weeks. In addition, whitefly can pose a great threat to plant health because they are able to transmit many plant viruses.
A whitefly looks like a small white moth, 1/8″ in length. They rest on plant leaves and will quickly fly away when disturbed. Whitefly lie their eggs on the under side of a leaf. Shiny, sticky leaves are signs of whitefly presence.
The Biological Control for the Whitefly is the Encarcia Formosa. This tiny parasitic wasp lays its eggs in the larvae of the whitefly. Parasitized larvae turn black and are easily recognized. Adult EncarsiaFormosa also feed on honeydew and the body fluids of whitefly larvae.
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