Gardening, Landscaping and Weed Sciences includes a wide range of topics which include,
- The biological and ecological nature of weeds in agriculture, forestry, aquatic, grass, recreational, rights-of-way, and other contexts; and weed genetics.
- The biological and ecological elements of weed control techniques, such as biological agents and herbicide-resistant crops
- Herbicide resistance, herbicide chemistry, biochemistry, physiology, and chemical action of herbicides as well as plant growth regulators used to control unwanted vegetation
- Cropping as well as other agricultural systems’ ecology as it relates to weed management
In this post you can learn about
- 1 Effective Management Practices and Recommendations for Mitigating the Chances of Herbicide Resistance
- 2 Weed control alternatives to glyphosate are being tested in major perennial crops.
- 3 Herbicide-resistant crop volunteer interference and management
- 4 The action of protoporphyrinogen oxidase inhibitors is increased by glufosinate.
- 5 Herbicide Resistance: Understanding Resistance Evolution as well as the Effects of Herbicide-Resistant Crops
- 6 Weed Control in Monocultures and Mixtures of Cover Crops
Effective Management Practices and Recommendations for Mitigating the Chances of Herbicide Resistance
The field of weed science is at a crossroads. Decades of effective chemical weed management have resulted in an increase of herbicide-resistant weed species, with few new herbicides with novel modes of action to combat this trend and, in many cases, no economically viable alternatives to herbicides in large-acreage crops. Simultaneously, the global population is increasing, needing more food production to sustain an estimated 9 billion people by 2050. Here, we explore these obstacles, as well as new trends in technology and innovation that provide promise for long-term weed control.
Weed control alternatives to glyphosate are being tested in major perennial crops.
The development of natural product leads in the emergence of new herbicides as well as biopesticides implies that new modes of action are possible, while genetic engineering gives further possibilities for modifying herbicide selectivity and generating totally unique methods to weed management. Understanding plant pathogen interactions will aid in the development of novel biological control agents, and insights into plant–plant interactions indicate that crops might be enhanced by controlling their response to competition. Revolutions in computer power and automation have spawned a fledgling business based on the use of machine vision as well as global positioning system data to differentiate weeds from crops and offer precise weed control. These technologies bring up new avenues for effective weed management, whether it be through chemical or mechanical means.
Herbicide-resistant crop volunteer interference and management
Volunteer imidazolinone-resistant (IR) barley or wheat can cause problems in rotating crops, especially when IR crops like canola or wheat are planted. Due to high fecundity, seed loss before or after harvest, and secondary seed dormancy, HR canola volunteers are common in the Northern Great Plains, and they can interfere with crops planted in rotation, such as flax.
HR corn volunteers compete in rotational crops like corn, cotton, soybean, as well as sugarbeet, with yield reduction dependent on the concentration of HR corn volunteers. Volunteer HR cotton, rice, soybean, and sugarbeet aren’t a big issue and can be managed with current herbicides. If the crop volunteers are several HR, pesticide options are restricted; thus, documenting the cultivar sown the previous year and picking the right herbicide is critical.
The action of protoporphyrinogen oxidase inhibitors is increased by glufosinate.
Glufosinate increases the action of PPO inhibitors by increasing glutamate and protoporphyrin levels, resulting in increased ROS and lipid peroxidation. The synergism of the two herbicide MoAs may aid in overcoming environmental factors that restrict glufosinate’s effectiveness. Future study is required to optimise the usage of this herbicidal composition across various cropping systems.
Herbicide Resistance: Understanding Resistance Evolution as well as the Effects of Herbicide-Resistant Crops
The advent of herbicide-resistant crops had resulted in substantial changes in agronomic practices, one being the adoption of effective, simple, low-risk crop-production methods that rely less on tillage and use less energy. Total, the adjustments have had a beneficial environmental impact by lowering soil erosion, tillage fuel usage, and the number of herbicides with groundwater warnings, as well as a modest decrease in the overall impact on the environment quotient of herbicide use. Herbicides, on the other hand, provide a significant selection pressure on weed populations, and the density and diversity of weed communities fluctuate over time in response to herbicides and other management methods.
Repetitive and intensive usage herbicides with the same mechanisms of action (MOA; the mechanism in the plant that the herbicide negatively impacts so that the plant succumbs to the herbicide; e.g., the inhibitory activity of an enzyme that is vital to plant growth or the inability of a plant to metabolize the herbicide before it has done damage) can rapidly select for shifts to tolerant, difficult-to-controversial plant species.
Weed Control in Monocultures and Mixtures of Cover Crops
Planting mixes of cover crop species has gained in popularity in recent years as farmers strive to expand the range of ecosystem services provided by cover crops. We assessed the degree to which cover crop monocultures and mixes control weeds during the fall-to-spring cover crop growth season as part of a multidisciplinary study. Weed-suppressive cover crop stands can reduce weed seed rain from summer and winter annual species, limiting weed population expansion and, eventually, weed pressure in future cash crop stands. In a lengthy autumn growth window following winter wheat harvest and a shorter window following silage corn harvest, we established monocultures and mixes of two legumes (medium red clover and Austrian winter pea), two grasses (cereal rye and oats), as well as two brassicas (forage radish and canola).
Grass cover crops and mixes were the most weed suppressive in the fall of the long window, whereas legume cover crops were the least. Weeds were successfully controlled by all of the combinations. This was most likely due to the existence of quickly grass species, which were effective even when planted at 20% of their monoculture rate. Weed biomass were low in all treatments in the spring due to winter death of summer-annual weeds and poor germination of winter annuals. The biomass buildup by crop rotation and weeds in the fall was more than an order of magnitude lower in the short window after silage corn than in the longer window.
However, weed seed generation was significant in all treatments that did not contain grain rye in the spring (monoculture or mixture). Our findings imply that cover crop combinations with aggressive grass species only require low planting rates to offer weed control. This opens the door for other species to provide additional ecosystem services, however careful species selection may be necessary to preserve mixture variety and avoid winter-hardy cover crop grass dominance in the spring.