| Rice resistant weeds are becoming more and more resistant with the overuse of herbicides.Resistance to barnyard grass and rice barnyard grass was the most serious.At the present stage,the method to prevent and control barnyard grass and barnyard grass can only be the stem and leaf treatment at the early stage after the closure,and the herbicide product is mainly penoxsulam.Due to the use of too few replacement herbicides in successive years,the resistance of weeds gradually increases,leading to the increased use of herbicides and the failure to eradicate weeds,resulting in serious economic losses.The increased resistance of paddy weeds to chemical herbicides makes weeding more difficult and increases the cost.Chemical herbicides also threaten the paddy field ecosystem and reduce the yield.Therefore,the root control of resistant weeds and the reasonable combination and use of chemical herbicides are the most urgent tasks to ensure the production of rice in China.This experiment through the equivalent line method,the determination of the five fluoride sulfonic grass amine and pyrazole its mix of cycling control effect,through to the rice barnyard grass and equivalent line can be seen that the rain for a long time spend five fluoride sulfonic grass amine and pyrazole its cycling when the medication roughly 2:1 synergy is the most significant,and five fluoride sulfonic grass amine and pyrazole its cycling after matching rice barnyard grass seems best for five fluoride sulfonic grass applying Anderson,38.46 g/hm~2,pyrazole its cycling use of Anderson,18.77 g/hm~2,The optimal application amount for hyacinthus japonica was 36.03g a.i/hm~2 for pentafluorosulfonate and 28.58 g a.i/hm~2 for pyrasulfuron.The experiment confirmed the application effect of the compound agent to better control weeds in the rice field.In addition,the optimal ratio was compared with the dose,and the safety of paddy fields was analyzed.Relevant studies concluded that:1.Plant height,tillering,leaf age and fresh weight are representative indicators that determine the growth and development status of rice,and the quality of growth and development has a great impact on the final yield.At 2 days,5 days and 15 days after transplanting,the inhibitory effect of plant height showed a trend of increasing first and then decreasing with the increase of dosage.However,the inhibitory effect of plant height was different with the different transplanting time.The later the transplanting time was,the less the inhibitory effect of plant height was.When the dosage was 150 g a.i/hm~2,the inhibitory effect on plant height was the strongest.Tillering number and fresh weight at 49 d after application showed a decreasing trend with the increase of dosage.2.The effect of the application amount on SOD,POD and CAT in the oxidation system of rice indicated that SOD activity of leaves increased with the increase of the application amount,and decreased when the application amount was up to 200 g a.i/hm2.In addition,SOD was significantly affected 4 weeks after application,and the longer the application time,the less the effect.After application,the same dosage showed a trend of first increasing and then decreasing from 7d to 49d,both higher than CK.As can be seen from the different dosages at the same time point,POD activity of leaves increased gradually with the increase of dosages.CAT activity increased first and then decreased with the increase of dosage at the same time.At the same dosage,CAT activity decreased gradually after 35d,and CAT activity was significantly affected in the first4 weeks after spraying.3.With the increase of dosage,the brown rice rate gradually increased;At 100 g a.i/hm~2,the white rice rate reached the highest,significantly higher than that of CK.When the dosage exceeded100 g a.i/hm~2,the white rice rate showed a gradually decreasing trend.In the effect of the mixture on the appearance quality of rice,chalkiness rate and chalkiness degree were not significantly changed with the increase of the dosage compared with CK.The compound herbicide had no effect on the nutritional quality of rice.4.With the increase of dosage,the number of ears,seed setting rate,grain number per ear and measured yield of rice all showed a trend of increasing first and then decreasing.The panicle number,seed setting rate and panicle grain number of rice reached the maximum when the dosage was 100 g a.i/hm~2.The amount of drug applied exceeded 100 g a.i/hm~2,and the number of ears,seed setting rate and grain number per ear gradually decreased.When the dosage was 100 g a.i/hm~2,the maximum value was reached,and the yield was significantly increased by 0.76%compared with CK.When the dosage was more than 100 g a.i/hm~2,the yield gradually decreased.To sum up,in this experiment,the highest yield and the best yield characteristics of rice were obtained when the dosage of the compound was 100 g a.i/hm~2 at the optimal ratio. |
