Introduction
Herbicides are used by farmers to control the population of specific weeds in their farms, but genetic mutations in the part of some weed species can lead to their development of resistance against the herbicides. Herbicide resistance results in an increase in the population of the associated weeds because they become difficult to control. Herbicide-resistant weeds may dominate the farm after several years of applying the same herbicide; hence. Farmers are advised to keep a close eye on the effectiveness of the herbicides used to control specific types of weeds. Normally, weeds become resistant to one or more groups of herbicides. This paper looks at herbicide-resistant weeds with a close focus on how weeds develop resistance against herbicides and the options that farmers have for controlling these weeds.
What causes herbicide resistance in weeds
Studies have revealed that weeds usually develop resistance when farmers continue using the same herbicides for a long time. This is normally associated with monoculture in the farm whereby the farmers are compelled to use herbicides recommended for a crop repeatedly. The resistance is caused by genetic mutations in the weeds, whereby they adapt to the herbicide environment for survival purposes. As farmers continue using the same herbicide, the species that are not adapted to the chemicals are wiped out, and the resistant species continue to multiply. Resistant weeds pass their mutated genes to the succeeding generations, and this makes the associated herbicides useless in controlling the specific weeds. It is important to understand that the chemicals in the herbicides do not cause the development of resistance by the weeds. Resistance is caused by the evolution of some of the weeds, which possess the ability to survive under the chemical environment caused by the herbicides (How Weeds Become Resistant, 2015).
Preventing herbicide resistance in weeds
Farmers need to use herbicides sparingly on their farms. They need to use the chemicals only when it is necessary to prevent the development of species that are resistant to herbicides. It is also advisable to use a combination of different groups of herbicides to get rid of the species that might be resistant to one or more groups of herbicides. Crop and herbicide rotation may also be a viable approach to preventing the development of resistance (Caseley, Cussans & Atkin, 2013).
How to deal with herbicide-resistant weeds
It is common to find resistant weeds on the farm, and farmers need to know the best ways to deal with the situation. In such cases, the farmer should change his or her herbicides or use a combination of herbicides that enhance the effectiveness of controlling weeds. It is also viable for farmers to plant cover crops that smother the weeds over time. An integrated weed management approach should be applied where the weeds are notorious. The approach entails crop rotation and planting a mixture of crops to ensure that the crop-specific weeds are killed (Herbicide Resistant Weeds, 2015).
Conclusion
Herbicide resistance in weeds is one of the major challenges that farmers across the world are facing. Weeds develop resistance to herbicides when specific species of the weed adapt to the chemical environment caused by the herbicides. These resistant genes are passed on to the next generations of the weeds, and this increases the population of the resistant species. Farmers should use different herbicides on their farms every season, and they should practice crop rotation to kill the resistant weeds.
References
Caseley, J. C., Cussans, G. W., & Atkin, R. K. (2013). Herbicide resistance in weeds and crops. Amsterdam: Elsevier.
Herbicide Resistant Weeds. (2015) Web.
How Weeds Become Resistant. (2015). Web.