Screening Of Herbicides And Effects Of S-metolachlor On Soil Quality In Buckwheat Field

Buckwheat as a kind of health food is more and more concerned by people. Inner Mongolia is the main planting area of buckwheat in China. Field weeds and buckwheat compete for water, for fertilizer, the space is an important factor affecting the yield and quality. At present, there are no available weed herbicides on buckwheat field, people take artificial weeding when serious harm, but the cost is higher. Therefore, this study first investigated the types, hazards and occurrence of weeds in buckwheat field, selecting 31 kinds of herbicides commonly used in the production of screening test, and studied the possibility of sowing date and density controlling weeds, further studied the herbicides of buckwheat dual gold weed control effect and impact on soil quality. In order to explore the comprehensive measures of weed control. Results show:1.Buckwheat crop distribution is mainly dry weeds, different types of weeds are in different geographical environment, mainly are PanicummiliaceumL.var.ruder aleKit., Chenopodium album. Fallopia convolvulus, Sonchus brachyotus DC.2.Buckwheat crop can use S-metolachlor, Kim-Chaoer and Ethyl amineweedin g. It’s safety and toxicity to buckwheat, and the revention effect is high, the incre-ase production effect is obvious. Buckwheat field can use Vimak and quizalofop-p-ethyl in weeding gramineous grass, and the yield increasehaloxyfop-methyl and prometryn on the weeds in the buckwheat field was poor, whichcan not be used to weed the buckwheat field. Prohibit the use of herbicides Tian Pu, trifluralin The net again、atrazine、Bean free、shuangcaoch、nicosulfuron、yulebao、paraqu-at、yucaoke、Fluroxypy、Carbadox oil、tribenuron-methyl、MCPa in buckwheat c-rop.3.The dosage of S-metolachlor are 60-80ml/667m2, water consumption are 60kg/667m2, can effectively control weeds in buckwheat field. When the dosage of S-metolachlor are 80ml/667m2,grass control effect is 97.1%,broad grass control effect is 85.3%, And can increase production.4.In the experiment of sowing date and density, the best spacing is 35cm, weed control number is 22.6%, the fresh weight of the control was 31.9%;June 10th is the best sowing date. Weed control was 20.4%, the fresh weight of the control was 55.3%.5.S-metolachlor’s different concentration have varying degrees of impact on the number of microorganisms in wheat buckwheat and activity of various enzymes. The application of S-metolachlor (30d) has inhibitory effect on soil bacteria, fungi and actinomycetes, but the application of fungi, bacteria and actinomycetes recovered(after 40d). Before using S-metolachlor 30d can inhibit the activity of soil urease and catalase, after 30d,2 kinds of enzyme activity can be recovered,2 kinds of enzyme activity increased when 60d. Each concentration of s-metolachlor can suppress soil invertase activity.6.Dynamic analysis shows that S-metolachlor residue in soil, with the increasing concentration of s-metolachlor herbicides, herbicide residues are also increasing. And with the increase of herbicide residues, resolution rate also increased.