Screening Of Mixed Formula About Prometryn And Oxadiazonand Rice Paddies Application Technology Research

In order to solve the control problem of sagittaria trifolia in the rice fields, as the same time to extend the usage time of oxadiazon and reduce the application amount of promrtry, improve the herbicidal activity, In this paper, mix effect and the best formula combination of promrtry and oxadiazon was studied by co-toxicity coefficient method、isoboles method and two factors and five levels of orthogonal rotation combined design method, and carried out the impact of the mix of the two reagents on the security of rice.Conclusion:1、The three methods showed that the mixture of promtry and oxadiazon had obvious synergistic action. The co-toxicity coefficient method result show that the ratio1:0.7、1:0.9、1:1.1、1:1.4and1:2.4had synergism forsagittaria trifolia,andsagittaria trifolia at the ratio of1:0.9had highest co-toxicity coefficient which were161.41.The mixed use of promrtry and oxadiazon had no antagonism within the scope in proportion2、Isoboles method was found that control efficacy of promrtryapplication rate ranged from361.05-403.30ga. i.·hm-2and oxadiazon ranged from340.70-393.50ga. i.·hm-2Two factors and five levels of orthogonal rotation combined design method result showed that the best formula combination of promrtry and oxadiazon was403.30ga.i.·hm-2and393.50ga.i.·hm-2through the optimization analysis of control efficiency model,,and the stem control effects for sagittaria trifolia were82.33%. Co-toxicity coefficient methodestimated that promrtry and oxadiazon at the ratio of1:0.9was the best formula combination, isoboles method and two factors and five levels of orthogonal rotation combined design method also got the same result.3:The experiments were carried out the impact of the mix of the two reagents on the security of rice by pot experiment.Spray voume:700、730、760、790、810ga. i.·hm-2(1) The mixtureof the two agents had little effect on each physiological indexes of the tested rice varieties and thesecurity using dosage was760ga.i·hm-2in HeiLongjiang Province,Co-toxicity coefficient methodestimated that promrtry and oxadiazon at the ratio of1:0.9was the best formula combination.Experiments showed that mixture of promrtry and oxadiazon could usein DongNong425、KongYu131、LongJing31,with little influence. But when dosage was810ga.i.·hm-2,Restroability to DongNong428and DongNong427under790ga.i.·hm-2.No harm under760ga.i.·hm-2each physiological indexes such as root activity of rice which hiegh and weigh of plant was affected about840ga.i.·hm-2.(2)Apply to HeiLongJiang under the700ga.i.·hm-2application rate. The harm increase with the spray volum when it over730ga.i.-hm"2to DongNong425DongNong427. Over800ga.i.·hm-2couldn’t be normal growth. Seriously affect the normal development of rice.(3)The mixture of promrtry and oxadiazon is more useful during divided leafy period than common.None unrecoveable phytotoxicity symptoms to KongYu131which transplant7days and14days the spary volum over810ga.i.-hm-2. But,more than760ga.i.-hm-2to KongYu131in21days after planting,the tested rice varieties could be normal growth.And seriously affect the normal development of rice.