14 herbicides commonly used in rice fields
At present, there are about 15 kinds of weeds that mainly damage rice fields, 53 kinds of common weeds, 24 kinds of grasses, 19 kinds of broadleaf grasses, and 10 kinds of Cyperaceae.
Due to the mixed growth of multiple weeds in the same field in the rice field, the resistance of a variety of major harmful weeds to commonly used herbicides has developed rapidly, the refractory weeds spread rapidly, and the occurrence area has increased, making it more and more difficult to control weeds in rice fields. . Therefore, based on the current resistance to herbicides in paddy fields and market use, a brief introduction to 14 commonly used pesticides is made.
1. Amide herbicides
Pretilachlor is a kind of selective herbicide. It is principally used for weeds of barnyardgrass, psrandletop, nutgrass, ducktongueweed in rice seeding bed and direct seeding. The period of validity shall be for 30-40 days. In rice direct seeding usually mix with soil or spray with water-mix. In rice seeding bed you will spray with Validity water-mix.
Mefenacet is a systemic conductive herbicide. It can effectively control gramineous weeds. Control of grass weeds, especially Echinochloa crus-galli, and some broadleaf weeds in transplanted rice. Mefenacet Mainly used in combination with other compounds.
Selective systemic and conductive herbicide, suitable for direct seeding and transplanting of rice. Absorbed primarily by the germinating shoots, and secondarily by the roots, with translocation throughout the plant, giving higher concentrations in vegetative parts than in reproductive parts. Used pre-emergence for the control of annual grasses and certain broad-leaved weeds in rice, both seeded and transplanted. Activity is dependent on water availability such as rainfall following treatment, overhead irrigation or applications to standing water as in rice culture.
2. ACC enzyme inhibitor, fatty acid synthesis inhibitor
Efficient post-emergence selective herbicide for controlling gramineous weeds. It is used to treat the stems and leaves of rice fields to control crabgrass, barnyardgrass and other gramineous weeds. Compared with other compounds, oxadifen is relatively safe. Many weeds that have developed resistance to Quinclorac, Penoxsulam, and Bispyrifen can still be controlled by oxfentrazone.
The systemic conductive herbicide is mainly used to control important gramineous weeds. Cyhalofop-butyl post-emergence herbicide with foliar uptake only and no soil activity. For post-emergence control of grass weeds in rice.
3. Hormonal herbicides
postemergence herbicide used for selective control of broadleaf weeds and sedges in rice, corn. Bentazone is a contact herbicide, which means that it causes injury only to the parts of the plant to which it is applied . It interferes with the ability of susceptible plants to use sunlight in the production of energy for survival, a process called photosynthesis. Visible injury to the treated leaf surface usually occurs within 4 to 8 hours, followed by plant death.
(2) 2 methyl 4 chlorine (type)
Phenoxyacetic acid-based selective systemic and conduction hormone herbicides are used in the greening period after rice transplantation. They can effectively control sedges and broad-leaved weeds in rice fields, such as heteromorphic sedges, trigonal grasses, and water peanuts. Pay attention to low temperature or excessive use, or apply the medicine before the 4-leaf stage and after jointing, which is prone to phytotoxicity.
Systemic and conductive post-emergence herbicide, used to control broad-leaved weeds, such as purslane, duck broadweed, polygonum and water peanut, etc. It is not effective to grass weeds.
Quinclorac is a disubstituted quinolinecarboxylic acid that is part of a new class of highly selective auxin herbicides. Quinclorac is used in rice to control dicotyledonous and monocotyledonous weeds , particularly barnyardgrass (Echinochloa crus-galli). Quinclorac is also used for weed control in turfgrasses.
4. ALSase inhibitor
Selective systemic and conductive paddy field herbicide, which can control annual and perennial broad-leaved weeds and Cyperaceae weeds, Control in paddy fields for annual and some perennial broadleaf weeds and sedge weeds; added security agents can be used in wheat field.
Selective systemic and conductive herbicide, its efficacy is not affected by temperature, and its efficacy is long-lasting. It can control weeds in direct-seeding rice fields, transplanting fields, and throwing seedling fields, and can control annual and perennial broad-leaved weeds and cyperaceae weeds.
Penoxsulam has a good control effect on many subspecies of Echinochloa crus-galli. Its low dosage, high safety to rice, safe to subsequent crops, and flexible use method: it can be used as post-emergence stem and leaf spray or poisonous soil treatment.
Selective pre-emergence and post-emergence herbicides, Effective against mono- and dicotyledonous weeds in rice.
In the paddy field market, Pendimethalin is selective herbicide.Control of most annual grasses and many annual broad-leaved weeds in cereals.