Application Of Pyrazosulfuron-ethyl Research Articles

Influence of New Generation Herbicide on Microbial Biomass Dynamics in Sandy Loam Soil

A laboratory experiment was conducted with two new generation herbicide pyrazosulfuron ethyl treatments, namely, recommended dose 15 g a.i. ha-1 (RD) and 30 g a.i. h-1 (2RD), carfentrazone ethyl 25 g a.i ha-1(RD), 50 g a.i. ha-1 (2RD) along with control (without herbicide) applied to sandy loam soil to determine their effect on microbial biomass dynamics in soil. The application of pyrazosulfuron ethyl (T1 and T2) and carfentrazone ethyl (T3 and T4) did not show any significant effect at 0 day after application. While, at 7 days after application of herbicide declined soil microbial biomass status. Whereas, at 28 days after application significantly increasement microbial biomass carbon and microbial biomass nitrogen except for microbial biomass phosphorus under herbicidal treatments compared to untreated plot. Hence, pyrazosulfuron and carfentrazone ethyl may cause short term transitory change in microbial biomass dynamics in soil moreover at 28 day after application of herbicide no any harmful effect at recommended dose of pyrazosulfuron ethyl and carfentrazone ethyl.

Effect of different herbicide spray volumes on weed control efficiency of a battery-operated Unmanned aerial vehicle sprayer in transplanted rice (Oryza sativa L.)

The effect of spray volume on weed control in transplanted rice ecosystems using the Unmanned aerial vehicle (UAV) needs to be better understood for management in the advancements of UAV-based spraying technology. The present study aimed to find out the influence of varied spray volumes of 15 L/ha, 20 L/ha and 25 L/ha using the UAV and 500 L/ha using a Knapsack sprayer (KS) to compare the weed density, weed dry matter and weed control efficiency and yield in transplanted rice (Oryza sativa L.). Pre-emergence (PE) application of Pyrazosulfuron-ethyl at 25 g a.i./ha at three days after transplanting (DAT) and post-emergence (PoE) application of Bis-pyribac sodium at 25 g a.i./ha at 25 DAT were used as herbicide treatments. The results revealed that varied spray volumes significantly influenced the weed density, dry matter, and weed control efficiency of the UAV and KS. Application of herbicides using KS (500 L/ha) and UAV (25 L/ha) had better control on the weeds by reducing weed density and dry matter at 20, 40, and 60 DAT, with no significant difference. Higher grain yield and straw yield were recorded in KS (500 L/ha) and UAV (25 L/ha), with no significant difference. However, applying 25 L/ha had better weed control efficiency and higher yield, possibly due to optimum deposition. Considering the low volume application of UAV (25 L/ha) as compared with KS (500 L/ha), it is better to go for the optimal application of 25 L/ha, which is an energy-efficient and cost-effective, labour-saving approach compared to KS.

Weed management in direct-seeded rice under a long-term conservation agriculture-based rice rice (Oriza sativa)-wheat (Triticum aestivum) system

Weeds that occur in repeated flushes pose major challenges to direct-seeded rice (DSR). Zero till (ZT) DSRwith crop residue influences weed interference considerably and can be substitutive to resource-intensive puddledtransplanted rice (PTR). Field experiments were conducted at ICAR-Indian Agricultural Research Institute during2018–19 involving conservation agriculture (CA)-based DSRs and weed control/herbicides treatments to appraiseweed interference and productivity under an eight-year old CA-based rice-wheat system (RWS). All DSRs encountered more weeds than PTR. A double ZT system without residue [~ZTDSR-ZT wheat (ZTW); C1] had highest density and dry weight of grassy weeds, but a triple ZT system without residue [~ZTDSR-ZTW-ZT mungbean (ZTMB);C4] had highest density and dry weight of broad-leaved and sedge weeds. However, a triple ZT system with threecrops residue [~ZTDSR + mungbean residue-ZTW + rice residue-ZTMB + wheat residue; C5)] could reduce weedinterference significantly and led to 9.3% and 21.8% higher rice yield than C1 and C4, respectively. The applicationof pyrazosulfuron-ethyl 0.025 kg/ha pre-emergence followed by (fb) cyhalofop-butyl 0.100 kg/ha at 20 days aftersowing (DAS), fb bispyribac-Na 0.025 kg/ha at 25 DAS (W4) led to significant reduction in grassy, broad-leaved andsedge weeds densities by 92.5, 96.6 and 67.7%, respectively. The triple ZT system with rice, wheat and mungbeanresidues (C5) combined with application of pyrazosulfuron-ethyl fb cyhalofop-butyl fb bispyribac-Na (W4) gavealmost similar rice yield with PTR (C6). This may be recommended for adoption in Indo-Gangetic Plains (IGP) ofIndia and in similar agro-ecologies of the tropics/sub-tropics.

Variation in mutations providing resistance to acetohydroxyacid synthase inhibitors in Cyperus difformis in China

Cyperus difformis has evolved resistance to pyrazosulfuron-ethyl and other acetohydroxyacid synthase (AHAS) inhibitors in paddy fields in China. To understand the distribution of resistance and the mutations involved, 38 populations collected were from 7 provinces and compared. Application of pyrazosulfuron-ethyl at 30 g a.i. ha−1 identified 16 populations that survived, demonstrating resistance to this herbicide. Two exons of 498 and 1428 bp in length and a 1228–1233-bp intron of AHAS were cloned by genome walking, and three pairs of primers were designed to amplify eight conserved regions in this gene. In the 16 resistant (R) populations, five different types of mutations in the conserved region of the AHAS gene were identified: Pro-197-Ser, Pro-197-Arg, Pro-197-Leu, Asp-376-Glu, and Trp-574-Leu. Three R populations, YX15-22, YX12-10 and YX15-38, were chosen for in vitro AHAS activity assays, and the results showed that AHAS from YX15–22 carrying the Pro-197 mutation was insensitive to pyrazosulfuron-ethyl (resistance index (RI) = 310.0) and penoxsulam (RI = 10.0), whereas the enzyme from YX12–-10 and YX15-38 was insensitive to pyrazosulfuron-ethyl, penoxsulam, imazapic and bispyribac‑sodium (RI values ranging from 4.3 to 4462.0). AHAS inhibitor cross-resistance bioassays showed that YX12-10 and YX15-38 had cross-resistance to all of the tested herbicides (RI values ranging from 5.8 to 3321.9), while the YX15–22 population only had resistance to pyrazosulfuron-ethyl (RI = 827.4) and penoxsulam (RI = 6.6). This study clarified the distribution of resistant C. difformis in China and the different cross-resistance patterns given by various mutation types of AHAS.

Performance of pyrazosulfuron-ethyl in non-puddled transplanted rainy season rice and its residual effect on growth of the succeeding crop in rice-wheat cropping pattern

A study was carried out in sandy clay loam textured soil of Mymensingh, Bangladesh to evaluate weed control efficiency of pre-emergence herbicide pyrazosulfuron-ethyl either alone or in sequential application with post-emergence herbicide in transplanted rainy season rice under non-puddled strip-tilled (NPST) field condition and also to examine the residual effect of those herbicides on germination and growth of the subsequently grown wheat crop. Five treatment combinations of pyrazosulfuron-ethyl were tested against one weedy check and one weed-free check. The study revealed that NPST rice field was mostly infested by grass and sedge weeds and herbicide treatments offered a wide range of control (above 50% to 95%) on all types of weeds. Application of pyrazosulfuron-ethyl followed by (fb) orthosulfamuron fb butachlor plus propanil provided the most effective and economic weed control over two years of the study. Moreover, micro-plot bioassay study claimed germination and growth of subsequently grown wheat were not adversely affected by herbicides that were applied in rice. Therefore, application of pyrazosulfuron-ethyl followed by post-emergence herbicide could be effective and economic to control weeds in NPST rice under rice-wheat system, but proper rate and time of application should strictly be followed.

Performance of Pre- and Post-emergence herbicides in strip tillage Non-puddled transplanted Aman rice

A study was conducted on transplanted aman rice (cv. BINA dhan-7) in strip-tilled non-puddled field with some commonly used rice herbicides (pre-emergence: pyrazosulfuron-ethyl and butachlor, early post-emergence: orthosulfamuron and late post-emergence: acetochlor + bensulfuron methyl, butachlor + propanil and 2,4-D amine) applied singly or in sequences during 2013 and 2014 at field laboratory, Bangladesh Agricultural University, Mymensingh to evaluate the effect of those herbicides on weeds as well as growth and yield of aman rice in strip-tilled non-puddled condition. The study showed that herbicides significantly reduced weed density by 75-94% in 2013 and 46-98% in 2014 compared to the weedy check. Sole application of pre- or early post-emergence herbicide provided less weed control than sequential application of pre-, early post- and late post-emergence herbicides or application of pre- and late post-emergence herbicides. A wide range of sequential application of herbicide treatments has identified in the study that provided control on weed density and biomass by 49-98% and 56-95%, respectively. Application of pyrazosulfuron-ethyl followed by orthosulfamuron and butachlor + propanil was the most effective combination in this new rice establishment condition that controlled all types of weeds successfully and provided maximum grain yield (5.42 t ha-1 in 2013 and 6.18 t ha-1 in 2014) with highest economic return (Tk. 55930 ha-1 in 2013 and Tk. 69057 ha-1 in 2014). The study suggests economically beneficial some combinations of currently used herbicides for strip-tlled non-puddled transplanted aman rice that may help farmers to choose and rotate in the same land yearwise for obtaining optimum yield.Bangladesh J. Agril. Res. 42(4): 631-646, December 2017

Energy and nutrient utilization in rice (Oryza sativa)-weed ecosystem under post emergence herbicide application

A field experiment was carried out during 2010 and 2011 at the Research Farm of Krishi Nagar, J N Krishi Vishwa Vidyalaya, Jabalpur (Madhya Pradesh). The treatments consisted of weed control practices, viz. bispyribac sodium, penoxsulam, pyrazosulfuron-ethyl, cyhalofop-butyl + almix, fenoxaprop-p-ethyl + almix and control as main plot treatment and three day time application (morning, afternoon and evening) as sub plot treatment and laidout in split plot design in three replications. In rice (Oryza sativa L.)-weed ecosystem the solar energy utilization by weeds was maximum under control plot (836.46 and 786.52 lakh k cal/ha) where transplanting of crop was done without controlling of weeds, whereas pyrazosulfuron-ethyl treated plot registered lowest energy utilization (285.21 and 286.78 lakh k cal/ha) by weeds during both the years. The energy utilization by crop grain and straw was maximum with post emergence application of pyrazosulfuron-ethyl (527.83 and 533.65; 274.20 and 280.00 lakh k cal/ha). The studies on NPK removal by weeds and uptake by crop showed that the weed control treatments caused significant variations on these parameters. Application of pyrazosulfuron-ethyl also reduced the N (4.90 and 4.33 kg/ha), P (0.34 and 0.29 kg/ ha) and K (3.76 and 3.30 kg/ha) removal by weeds as compared to other herbicides and weedy check during both the years. The N (166.54 and 169.19 kg/ha), P (49.10 and 49.64 kg/ha) and K (170.95 and 173.13 kg/ha) uptake by crop was recorded higher with the application of pyrazosulfuron-ethyl. However, different day time application of post emergence herbicides was found statistically non-significant for energy and nutrient utilization by weeds and crop.