Explain the basis of biological control of weeds.
Basis of biological control of weeds: Biological control of weeds involves breeding of insects that would feed selectively a weed or use of certain micro-organisms which will produce diseases in the weeds and eliminate them. Certain crop plants do not allow the growth of weeds nearby. They are called smoother plants such as Barley, Rye, Sorghum, Millet, etc. They eliminate weeds through chemicals. In some cases, specially tailored plants called transgenic plants have been introduced which have tolerance against weeds. In India and Australia, the overgrowth of cacti was checked by the introduction of the cochineal insect (Cactoblastis cactorum). The latest technique is to use fungal spores to control weeds. These are suitable because they can be kept for a long time and also resist adverse conditions.
