propyrisulfuron, a new sulfonylurea herbicide for rice - Wssp.org.pk

232 Hajime Ikeda et al., Propyrisulfuron, a new Sulfonylurea…The shoot biomass (dry weight) was investigated at four weeksafter the application. The test was conducted with three replications.The data of the herbicide-treated plants were analyzed by thetwo-way ANOVA with the factors of ‘dose’ and ‘practice’ to determinethe effect of the application practices on the weed control efficacy.ApplicationApplicationwater1cmPolyethylene sheetPractice-1Practice-2Figure 2. The application practices to investigate the absorptionsite of Propyrisulfuron.Safety to ricePot tests were conducted in a greenhouse using 100 cm 2 × 14cm plastic pots filled with light clay soil (pH 6.1, organic matter 2.2%). After the soil was puddled and flooded, the seeds of rice (cv.Nipponbare and Basmati 370) were planted in the pots. The rice plantswere grown in a greenhouse up to 3 - 4-leaf stage.Propyrisulfuron was sprayed over the top of plants with avolume rate of 200 L/ha. The spray solution included 1 % Hasten TM , acrop oil concentrate. There is no flooding water at the application. Potswere flooded to 4 cm above the soil surface at three days after theapplication.The influence of propyrisulfuron on rice growth was evaluatedby comparing shoot biomass (dry weight) with an untreated control atthree weeks after the application.Statistical analysisThe statistical analysis mentioned above (non-linear regressionand ANOVA) was carried out with the software package, JMP TM ver. 4(SAS Institute Japan Ltd.).Weed controlIn the pot experiment, propyrisulfuron controlled troublesomeweeds of paddy fields, including Echinochloa, annual and perennialsedges, and annual and perennial broad leaf weeds at 25 - 100 ga.i./ha by submerged application (Figure 3).