Key Technical Points for Pre-Winter Weed Control in Wheat Fields
Pre-Winter Weed Control Techniques in Wheat Fields
The weeds in wheat fields in our county fall into two categories: broadleaf weeds and grass weeds. The broadleaf weeds are mainly flixweed (Descurainia sophia), shepherd's purse (Capsella bursa-pastoris), littlefield speedwell (Veronica polita), and cleavers (Galium aparine); the grass weeds are mainly wild oat (Avena fatua), jointed goatgrass (Aegilops tauschii), Poa sphondylodes, and bromegrass (Bromus japonicus). Wild oat and jointed goatgrass are mainly distributed in Cizhou Town, Jiangwucheng Town, Guanglu Town, and Gaoyu Town, while Poa sphondylodes and bromegrass are mainly distributed in the rice-growing area. In recent years, the results of our station's efficacy trials show that winter treatment of grass weeds in wheat fields achieves a corrected control efficacy of over 80%, while the efficacy of spring application is relatively poor. Therefore, pre-winter treatment of grass weeds in wheat fields should be vigorously promoted, as it not only requires a smaller amount of herbicide and lower cost with good results, but also reduces environmental pollution and the occurrence of drift phytotoxicity. According to recent surveys by plant protection personnel: weeds in wheat fields have been emerging one after another, and most of the weeds are at the one-leaf-one-heart to two-leaf-one-heart stage. In view of the above situation, the agricultural technology stations of each township (town) should actively organize each village and mobilize the masses to carry out pre-winter treatment of weeds in wheat fields.
Treatment period: generally around one month after sowing of winter wheat, when the wheat has 3-4 leaves and the weeds have 2-3 leaves. The suitable treatment time in our county is from the end of October to before November 15. During this period, the weeds in wheat fields have basically all emerged, the wheat field coverage is small, and the weeds are young and sensitive to the herbicide, and the higher temperature gives good efficacy.
Treatment methods: 1. In plots with severe jointed goatgrass infestation: use 30 milliliters of 3% Sigma (mesosulfuron-methyl) oil suspension concentrate per mu for uniform spraying; alternatively, use 20-25 grams of 3.6% BroadSigma (mesosulfuron-methyl and iodosulfuron-methyl-sodium) water dispersible granules per mu for uniform spraying, which also controls broadleaf weeds; 2. In wheat fields dominated by wild oat: in addition to treatment with Sigma or BroadSigma, 60-70 milliliters of 6.9% Puma per mu can also be used. 3. In plots where wild oat and jointed goatgrass occur together: Sigma can be used for uniform spraying at the 2-4 leaf stage of the weeds. 4. In rice-stubble wheat fields dominated by Poa sphondylodes and bromegrass, 20 grams of 15% Maiji (clodinafop-propargyl) wettable powder per mu can be sprayed for control. 5. In wheat fields dominated by broadleaf weeds: 10 grams of 10% tribenuron-methyl per mu can be sprayed for control.
Precautions:
When applying the herbicide, strictly follow the specified period and dosage, spray uniformly, and carry out the application in windless weather to prevent the spray solution from drifting onto other crops. The effect is best when the daytime temperature is above 10°C, and the minimum temperature for application must not be lower than 4°C.
Treatment period: generally around one month after sowing of winter wheat, when the wheat has 3-4 leaves and the weeds have 2-3 leaves. The suitable treatment time in our county is from the end of October to before November 15. During this period, the weeds in wheat fields have basically all emerged, the wheat field coverage is small, and the weeds are young and sensitive to the herbicide, and the higher temperature gives good efficacy.
Treatment methods: 1. In plots with severe jointed goatgrass infestation: use 30 milliliters of 3% Sigma (mesosulfuron-methyl) oil suspension concentrate per mu for uniform spraying; alternatively, use 20-25 grams of 3.6% BroadSigma (mesosulfuron-methyl and iodosulfuron-methyl-sodium) water dispersible granules per mu for uniform spraying, which also controls broadleaf weeds; 2. In wheat fields dominated by wild oat: in addition to treatment with Sigma or BroadSigma, 60-70 milliliters of 6.9% Puma per mu can also be used. 3. In plots where wild oat and jointed goatgrass occur together: Sigma can be used for uniform spraying at the 2-4 leaf stage of the weeds. 4. In rice-stubble wheat fields dominated by Poa sphondylodes and bromegrass, 20 grams of 15% Maiji (clodinafop-propargyl) wettable powder per mu can be sprayed for control. 5. In wheat fields dominated by broadleaf weeds: 10 grams of 10% tribenuron-methyl per mu can be sprayed for control.
Precautions:
When applying the herbicide, strictly follow the specified period and dosage, spray uniformly, and carry out the application in windless weather to prevent the spray solution from drifting onto other crops. The effect is best when the daytime temperature is above 10°C, and the minimum temperature for application must not be lower than 4°C.