Title: Study the efficacy of new herbicide Moonrice on weed control in paddy rice
Author: Bijan Yaghoubi
Abstract: The efficacy of the new herbicide Moonrice® (Bispyribac sodium, SC 10%) in the control of rice weeds in field conditions (in two locations, Rice Research Institute of Iran Rasht and Amol) and pot experiment (Rasht) during 2017 to 2019 were investigated. Field trial treatments consisted of 0, 50, 100, 150, and 200% of the average dosage of the desired Moonsrice® registrant (28 g ai.ha-1) and other recommended dosages of commercial Bispyribac sodium formulations in Iran including “Cleanweed”, “Nomini” and ” Vejin “and also hand weeding. Also in the pot experiment the efficacy of dosage 28 (g ai.ha-1) of Moonrice in controlling common water-plantain (Alisma plantago aquatica), false daisy (Eclipta prostrata), pondweed (Potamogeton nodusus), and barnyard grass (Echinochloa crus galli) in comparison with bentazon + MCPA (basagran), bispyribac sodium (two formulation Vejin and Chif), Pyribenzoxim (pyrimax), Pyrimax + Pertilaclor (Solitto), Triafamon + Ethoxysulfuron (Council), Flucetosulfuron (Zechor) and Metazosulfuroun (Altir) were investigated. Field experiment results showed that Moonrice caused (≥8%) toxicity and was able to recover well up to six weeks after transplanting rice. Moonrice had similar efficacy to the commercial formulations of this herbicide in controlling barnyard grass and bulrush (Schoenoplectous planiculmis) (excluding 50% dosage). The efficacy of doses of 28, 42, and 55 grams (ai / ha) of Moonrice was about 100% in barnyard grass control and slightly lower in bulrush control, and doses of 150 and 200% Moonrice had better performance (≥ 90%) in perennial weed bulrush. In general, weed biomass in Mazandaran was about one-quarter of Guilan and the average herbicide efficiency was slightly lower (about 70%) is probably because of delay in herbicide application. The pot experiment also confirmed the results of field results and the efficiency of Moonrice in controlling the four weed species was similar to the other investigated herbicides (90%). Tiller, panicle, biological yield, and grain yield of 100% and above the investigated dosage were about 300% more than weed control and similar to other herbicides. Yield loss in Guilan and Mazandaran provinces was 66% and 32%, respectively. Regarding no adverse effect of herbicides on rice, regression analysis of weed biomass was used to determine the appropriate herbicide dose for ED 95 (dosage required for 95% reduction in weed biomass). According to the results, 300 to 370 cc of Moonrice (SC 10%) is recommended for controlling barnyard grass and perennial weeds like a bulrush, respectively as a new rice cultivar in Giulan province.
Keywords: Foliar applied herbicides, ALS inhibitors, Performance comparison, New and old herbicides