There are over 250,000 plant species, among them only 1% (2500) are considered as weedy plant species, and 0.1% (250) are the most problematic weeds. However, these weedy species possess some special characters that help them to compete better than our desired crop plants.
Weeds are undesirable plants in a particular situation or in other words “A plant in the wrong place” and it can interfere with human activities. Taxonomically, the term “weed” has no botanical significance. However, weeds can cause serious economic impacts on horticultural production. Previous research has shown that in restricted areas of container production, they can cause reduction in growth of ornamental plants by 60%. There can be severe competition between ornamentals and weeds within containers for space, water, nutrients, air, and light within greenhouse conditions causing even deaths of ornamental crops. Weeds can also harbor pests and pathogens and can cause serious reduction in crop production, aesthetic sense, and market value of the crops.
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