Monoculture
Monoculture
Tightly controlled environment
Monoculture refers to the practice of cultivating an agricultural species under conditions where other species are absent or virtually absent. This is done in order to lessen the intensity of competition on growth of the desired crop species.
Selective breeding
The most extreme form of monoculture involves the cultivation of a single genotype of a crop species, to the exclusion of other genotypes and other species. Genetic monocultures may be grown in cases where plant breeders have developed strains of plants that are optimally adapted for growth under specific environmental conditions. In this type of monoculture, species are propagated asexually using cuttings, root grafts, or tillers. Examples of agricultural species that can be propagated asexually and therefore can potentially be grown as genetic monocultures include: (1) sugarcane (Saccharum officinarum ), which can be cultivated from rhizome cuttings, (2) bananas (Musa sapientum ), which can be propagated from tillers, (3) tea (Thea sinensis ), which can be grown from stem cuttings, (4) strawberries (Fragaria x ananassa ), which can be cultivated using runners, and (5) apples (Malus pumila ), cherries (Prunus avium ), and other trees of the rose family, which can be propagated using root grafts.
In comparison, planting a single species of seed results in a crop with more genetic variability than would be found in a monoculture. However, in some agricultural crops the seeds they may be derived from very closely-related or inbred strains of a species.
Tightly controlled environment
Usually, monoculture is practiced as a component of an intensively managed system, in which many environmental factors are controlled to optimize growth conditions for the crop. For example, other plant species are considered weeds, and are removed by hand weeding, manual cultivation, or through the use of a herbicide to which the desired crop species is tolerant, but the weeds are not. In addition, crops grown in monoculture are usually spaced optimally in order to decrease the competition among individual plants. The system may also be fertilized with inorganic nutrients so that nutrient availability does not limit productivity. The monoculture may be irrigated to decrease the importance of water limitations, protected with insecticides against insects, and treated with fungicides to reduce the incidence of diseases. All aspects of the monocultural system are designed toward the optimization of crop yield, to the degree that can be economically and ecologically achieved.
Bill Freedman