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Weeds are a major problem in potato production. Two years of trials were conducted to study the efficacy of herbicides and integrated use of mulch with herbicides in controlling weeds and for improving the growth and yield of autumn potato crop at Ludhiana, north-west India, during autumn 2016 and 2017. Each trial had a randomized complete block design with three replicates. There were 11 treatments including weed-free and weedy controls. Uncontrolled weeds caused a yield reduction of 49.7%. Metribuzin at 350 g/ha pre-emergence resulted in 82.4% weed control efficiency at 30 days after planting but this control was reduced to 23.9% at harvest. In contrast, metribuzin at 350 g/ha applied post-emergence controlled broadleaf weeds and grasses very effectively. Clodinafop at 60 g/ha post-emergence resulted in control of grasses only. The post-emergence application of pre-mix clodinafop plus metribuzin at 260 g/ha provided effective weed control and resulted in more tuber yield and economic returns and was significantly better than an application solely of metribuzin or clodinafop. The integrated weed control treatment of paddy straw mulch (PSM) at 6 t/ha with clodinafop plus metribuzin at 195 g/ha post-emergence resulted in the highest tuber yield with weed control efficiency of 95.3% at harvest. The next best one was an integrated treatment of PSM at 6 t/ha with metribuzin at 275 g/ha pre-emergence.

In the present research work, a novel and green TiO2 as an excellent photocatalyst has been synthesized and a comparative study of its structural, morphological and optical properties has been carried out with that of chemical synthesized. Green TiO2 has been synthesized using Titanium(IV)-iso-propoxide as a precursor and Lagenaria siceraria leaf extract has been used as a reducing and capping agent. Photocatalytic activity results indicate that TiO2 nanoparticles synthesized by green method exhibit excellent percentage removal (98.88%) of RG-19 dye in acidic medium as compared to chemical synthesized TiO2 sample which exhibits only 88.55% removal of dye. Higher apparent rate constant (0.02802 min−1) of photocatalytic reaction for green synthesized TiO2 nanoparticles as compared to that of chemical synthesized with apparent rate constant (0.0154 min−1), leads to the lower incubation time i.e., 60 min for green synthesized and 120 min for chemical synthesized. TiO2 nanoparticles synthesized via green synthesis offer high and fast removal of RG-19 dye as compared to chemical route. This study explores the green chemistry based TiO2 as an efficient photocatalyst with outstanding photocatalytic performance, which may open a new perspective for the preparation of excellent photocatalyst with cost-effective and environmentally friendly alternative to chemical and physical methods.

Pregnane X receptors (PXRs) regulate the expression of ATP-binding cassette proteins transporters and organic anion transporting polypeptides responsible for influx/efflux of xenobiotics across the brain. Ligand activation of PXR augments the expression of P-gp and promotes amyloid-β clearance across the blood–brain barrier. Dementia was induced in mice by intacerebroventricular administration of streptozotocin (STZ) followed by treatment with meclizine, a PXR agonist, and subsequently exposed to the Morris water maze test and biochemical and histopathological analysis to evaluate the effect on cognition. STZ-treated mice exhibited significant enhancement in brain thiobarbituric acid reactive species, interleukin-1β, tumour necrosis factor-α, myeloperoxidase, and acetylcholinestrase activity in addition to diminution in glutathione levels and superoxide dismutase activity in comparison to untreated mice. Administration of meclizine to STZ mice recuperated cognition and biochemical alterations. Concomitant administration of ketoconazole, a PXR antagonist, with meclizine prevented the protective effects. The upshots of our study proclaim that meclizine protects cognitive deficits by virtue of its antioxidant, anticholinesterase, and antiinflammatory properties. Results also signify the potential of PXR in neuroprotective actions of meclizine in dementia.

Herbicide resistance in weeds is a global threat to sustaining food security. In India, herbicide-resistant Phalaris minor was the major problem in wheat for more than two decades, but the continuous use of metsulfuron-methyl (an ALS inhibitor) to control broadleaf weeds has resulted in the evolution of ALS inhibitor-resistant Rumex dentatus L. This review summarizes the current scenario of herbicide resistance in R. dentatus, along with its ecology and management perspectives. Studies have provided valuable insights on the emergence pattern of R. dentatus under different environments in relation to tillage, cropping systems, nutrients, and irrigation. Moreover, R. dentatus has exhibited higher emergence under zero tillage, with high infestation levels in rice-wheat compared to other wheat-based cropping systems (sorghum-wheat). Alternative herbicides for the management of resistant R. dentatus include pendimethalin, 2,4-D, carfentrazone, isoproturon, and metribuzin. Although the pre-emergence application of pendimethalin is highly successful in suppressing R. dentatus, but its efficiency is questionable under lower field soil moisture and heavy residue load conditions. Nevertheless, the biological data may be utilized to control R. dentatus. Therefore, herbicide rotation with suitable spray techniques, collecting weed seeds at differential heights from wheat, crop rotation, alternate tillage practices, and straw retention are recommended for addressing the resistance issue in R. dentatus in North India conditions. Overall, we discuss the current state of herbicide resistance in R. dentatus, the agronomic factors affecting its population, its proliferation in specific cropping systems (rice-wheat), and management strategies for containing an infestation of a resistant population.

Dry-seeded rice has been introduced as an alternative to puddled hand-transplanted rice in the north Indian states of Punjab and Haryana. In dry-seeded rice, weed flora tends to be more diverse and weeds emerge in several flushes during the crop growth cycle and substantial yield reductions due to weed competition are quite common. The efficacy and compatibility of tank mixtures of different herbicides for the control of diverse weed flora in dry-seeded rice was evaluated in field experiments during the summer seasons of 2012 and 2013. The tank mixture of fenoxaprop with ethoxysulfuron improved the control of Echinochloa crus-galli and Echinochloa colona by 43-69% as compared to fenoxaprop alone while the tank-mix of azimsulfuron with fenoxaprop was antagonistic and reduced the control of Leptochloa chinensis by 86% as compared to fenoxaprop alone. Addition of azimsulfuron or ethoxysulfuron to bispyribac did not improve the control of grass weeds as compared to bispyribac alone. Weed control with the mixture of bispyribac and fenoxaprop varied over the two years. In 2012, bispyribac and fenoxaprop mixture was antagonistic for the control of Dactyloctenum aegyptium, Acrachne racemose, and L. chinensis but in 2013, there was no apparent antagonism and the addition of bispyribac to fenoxaprop reduced grass weed biomass as compared to fenoxaprop alone. In 2013, there was a strong negative correlation (r = -0.95, P < 0.001) between weed dry matter at 45 days after sowing and rice grain yield. According to the linear regression, rice crop is likely to produce no grain yield when weed dry matter exceeds 400 g m. Over the two seasons, fenoxaprop-ethoxysulfuron tank-mix produced similar grain yields (5.6-6.2 t ha) to the weed-free check (5.6-7.1 t ha). At the farmer fields, rice grain yield in the plots treated with pendimethalin followed by post-emergence bispyribac or a tank-mix of fenoxaprop + ethoxysulfuron ranged from 6.2 to 7.7 t ha as compared to 5.3-5.6 t ha in the plots treated with pendimethalin alone. The tank mixture of fenoxaprop with bispyribac needs further evaluation as this mixture has the potential to effectively control aerobic and aquatic grasses in dry-seeded rice. Single hand weeding prevented crop yield loss from weeds that escaped herbicide treatments only when it was performed within six weeks of sowing.

Plant cell wall formation is a complex, coordinated and developmentally regulated process. Cellulose is the most dominant constituent of plant cell walls. Because of its paracrystalline structure, cellulose is the main determinant of mechanical strength of plant tissues. As the most abundant polysaccharide on earth, it is also the focus of cellulosic biofuel industry. To reduce culm lodging in wheat and for improved ethanol production, delineation of the variation for stem cellulose content could prove useful. We present results on the analysis of the stem cellulose content of 288 diverse wheat accessions and its genome-wide association study (GWAS). Cellulose concentration ranged from 35 to 52% (w/w). Cellulose content was normally distributed in the accessions around a mean and median of 45% (w/w). Genome-wide marker-trait association study using 21,073 SNPs helped identify nine SNPs that were associated (p < 1E-05) with cellulose content. Four strongly associated (p < 8.17E-05) SNP markers were linked to wheat unigenes, which included β-tubulin, Auxin-induced protein 5NG4, and a putative transmembrane protein of unknown function. These genes may be directly or indirectly involved in the formation of cellulose in wheat culms. GWAS results from this study have the potential for genetic manipulation of cellulose content in bread wheat and other small grain cereals to enhance culm strength and improve biofuel production.

Background Studies have signified that high serum cholesterol plays an intriguing role in amyloid β metabolism and accumulation. Ligand activation of pregnane x receptors (PXRs), up-regulates the expression of P- glycoprotein and has a crucial role in amyloid β efflux. The present study has been undertaken to investigate the effect of forskolin, a PXR agonist in experimental dementia. Methods Wistar rats were allowed free access to cholesterol-rich High Fat Diet (HFD) for 90 days to induce dementia. HFD rats were then treated with forskolin (10 mg/kg; 20 mg/kg) followed by exposure to Morris water maze (MWM) test to deconvolute the mechanistic of learning and memory. An array of biochemical and histopathological tests were performed to demonstrate the extent of damage induced by HFD. Results HFD-treated rats exhibited marked accentuation in brain thiobarbituric acid reactive species, Interleukin-1β, tumor necrosis factor-α levels, myeloperoxidase and acetylcholinestrase activity in addition to attenuation of glutathione levels and superoxide dismutase activity as compared to rats fed on normal chow diet. Consistent rise in serum cholesterol level was also indicated. Histopathological examination of cerebral cortex using hematoxylin and eosin and congo red staining methods demonstrated significant neutrophilic incursion and amyloid deposition. Administration of forskolin to HFD treated rats improved memory functions, biochemical and histopathological alterations. Concomitant administration of ketoconazole, a PXR antagonist with forskolin prevented the observed protective effects. Conclusion Our findings signify that forskolin defends HFD induced cognitive deficits. Current plethora of results also defines the potential of PXR in neuroprotective action of forskolin in dementia.

Evolution of multiple herbicide resistance in Phalaris minor in wheat has resulted from the repeated use of herbicides with a similar mode of action which could threaten the sustainability of the rice-wheat cropping system in North-West India. In this context, field studies were conducted at Research Farm, Department of Agronomy, Punjab Agricultural University, Ludhiana during 2011–12, 2012–13 and 2013–14 in randomized block design replicated four times and at farmer's field during 2016–17 and 2017–18 with the objective to evaluate the efficacy of herbicide with alternative mechanism of action for the control of resistant P. minor in wheat. The treatments included pyroxasulfone 85, 102, 127.5 g/ha, pendimethalin 750 g/ha as pre-emergence (PE), sulfosulfuron 25 g/ha, clodinafop 60 g/ha as postemergence (PoE) and unsprayed control. However, the treatments during 2013–14 included pyroxasulfone 85, 102, 127.5 g/ha, pendimethalin 750 g/ha and unsprayed control with pendimethalin 1125 g/ha as PE at farmers’ field instead of pendimethalin 750 g/ha. The results indicated that pyroxasulfone at 127.5 g/ha recorded effective control of P. minor and its biomass and gave the highest wheat grain yield (4.87, 4.80 and 5.43 t/ha) during 2011–12, 2012–13 and 2013–14, respectively At farmer's field, pyroxasulfone 127.5 g/ha has been found effective against the resistant populations of Phalaris with 5.37 and 5.42 t/ha grain yield. The current study demonstrated that PE application of pyroxasulfone at 127.5 g/ha would be a suitable option for the control of resistant populations of Phalaris in wheat in Punjab.

The field efficacy of pre-and post-emergence herbicides for control of mixed weed flora in wheat was evaluated in a field study conducted at Punjab Agricultural University, Ludhiana during Rabi seasons of 2014–15 and 2015–16. The season long growth of weeds reduced wheat yield upto 38.5%. Pendimethalin and metribuzin recorded 65–73 and 73–78% control of Phalaris minor, respectively and their tank-mix application enhanced P. minor control to 78–85%. Pendimethalin and metribuzin recorded 26–33 and 5863% control of Medicago denticulata, respectively and their tank-mix application enhanced control to 77–92% of this weed. Pendimethalin and metribuzin provided control of Rumex dentatus to the extent of 98–100% and 68–92%, respectively, while provided 98–100 and 63–72%, respectively control of C. album. Sequential application of pendimethalin as pre-emergence followed by sulfosulfuron as post-emergence recorded the highest weed control efficiency (96%) and wheat grain yield (4.8 t/ha), and it was at par to pre-emergence pendimethalin + metribuzin, post-emergence pinoxaden + metsulfuron, mesosulfuron + iodosulfuron, sulfosulfuron + metsulfuron and two hand weeding.

A study was planned to evaluate efectiveness of new pre-mix herbicide metsulfuron methyl+chlorimuron ethyl for management of sedges and broadleaf weeds in transplanted rice at research farm of Punjab Agricultural University, Ludhiana for three years. The treatments comprised of metsulfuron methyl+chlorimuron ethyl 3, 4 and 5g/ha, azimsulfuron 20g/ha and metsulfuron 4 g/ha as post emergence and unsprayed control, replicated four times. The results indicated that the density and biomass of sedges and broadleaf weeds was signifcantly less in metsulfuron methyl+chlorimuron ethyl 4 and 5g/ha than 3g/ha, azimsulfuron 20g/ha, metsulfuron 4g/ha and unsprayed control. Application of metsulfuron methyl+chlorimuron ethyl 4g/ha applied in rice recorded signifcantly highest average grain yield of 7.31t/ha. There was a negative linear relationship between weed biomass and grain yield (r=-24.08). Correlation matrix revealed that all the yield attributes showed higher correlation with metsulfuron methyl+chlorimuron ethyl 4g/ha. Post emergence application of metsulfuron methyl+chlorimuron ethyl at 4g/ha resulted in efective control of broadleaf weeds and sedges in transplanted rice.

Seeds of isoproturon resistant Phalaris minor were collected from wheat fields and field experiments were conducted during winter season of 2012 and 2013. The biotype was found resistant to clodinafop-propargyl, fenoxaprop-pethyl and also showed cross resistance to pinoxaden. Mesosulfuron + iodosulfuron and sulfosulfuron provided 65 and 90 per cent control of the weed, respectively. Metribuzin recorded above 90 per cent weed control during both the years. Plants sprayed with metribuzin showed a sharp decrease in chlorophyll fluorescence (Fv/Fm ratio) of about 65 per cent as compared to control after 24 hours of spray even when there were no visible symptoms of herbicide injury. By this time, reduction in Fv/Fm ratio was less than 10 per cent for plants treated with ACCase and ALS inhibitors. At 15 days after spray, Fv/Fm ratio decreased by 11 to 13 and 23 to 30 per cent as compared to control for ACCase and ALS inhibitors, respectively.

A field experiment was conducted to study the bio-efficacy of herbicide combinations on mixed weed flora and productivity in puddled transplanted rice. Twelve treatments including bispyribac-Na 25 g/ha, penoxsulam 22.5 g/ha, bispyribac-Na 25 g + ethoxysulfuron 18.75 g/ha, tank-mix of bispyribac-Na 20 g + pre-mix of chlorimuron + metsulfuron 4 g/ha, pretilachlor 750 g followed by (fb) ethoxysulfuron 18.75 g/ha, pretilachlor 750 g fb pre-mix of chlorimuron+metsulfuron 4 g/ha, pyrazosulfuron 20 g fb pre-mix of chlorimuron + metsulfuron 4 g/ha, pre-mix of penoxsulam + cyhalofop 135 g/ha, pre-mix of triafamone + ethoxysulfuron 60 g/ha and pendimethalin 750 g at fb bispyribac-Na 25 g/ha along with hand weedings and weedy check were tested. Different herbicides recorded effective weed control and yield increase of 52–66% compared with weedy check. Unchecked weed growth depleted the soil of 234.2 kg N/ha, 17.6 kg P/ha and 292.7 kg K/ha. Sequential application of pyrazosulfuron and chlorimuron + metsulfuron (pre-mix) could not control grasses and yielded poorly compared with other herbicide combinations. Post-emergence, tank-mix application of bispyribac-Na with either ethoxysulfuron or chlorimuron + metsulfuron (pre-mix) recorded comparable yield to as obtained with sequential application of pendimethalin and bispyribac-Na or pretilachlor with either ethoxysulfuron or chlorimuron + metsulfuron (pre-mix).

A field experiment to study the efficacy of imidazolinone herbicides in greengram was conducted during Kharif seasons of 2012 and 2013. Ten weed control treatments viz. imazethapyr at 50 and 70 g, premix of imazethapyr + imazamox at 60 and 70 g/ha, both applied as post-emergence at 20 days after sowing; pendimethalin 1000 g and premix of pendimethalin + imazethapyr at 800, 900, 1000 g/ha, both applied as pre-emergence, along with two hand weedings and weedy check were evaluated. Imazethapyr alone and its premixes with pendimethalin and imazamox recorded effective control of mixed weed flora and produced significantly higher greengram seed yield than weedy check. Pendimethalin alone did not control Commelina benghalensis and recorded lower seed yield. All the herbicides were safe to crop.

Some weed species are not controlled by atrazine where the farmers are using this herbicide year after year and different flushes of weeds in rainy season are among the major problems in maize growing areas of India. A field experiment was conducted during the crop growing seasons of 2012 and 2013 at Research Farm, Department of Agronomy, Punjab Agricultural University, Ludhiana to evaluate the efficacy of glyphosate 41% SL against complex weed flora in maize. The treatments included glyphosate 41% SL 900, 1800 and 3600 g/ha applied as post-emergence at 2–4 leaf stage of weeds, atrazine 750 g/ha as preemergence, paraquat 24 SL 500 g/ha as post-emergence at 2–4 leaf stage of weeds, 2,4-D sodium salt 1000 g/ha as post-emergence at 2–4 leaf stage of weeds, weed free and unweeded control. The results revealed that non-selective herbicides paraquat at 500 g/ha and glyphosate at 900 and 1800 g/ha as a directed spray in maize as post-emergence at 2–4 leaf stage of weeds recorded effective control of grass and broad-leaf weeds during both the years and recorded grain yield at par with atrazine.

The field experiment was conducted at Students’ Research Farm, Department of Agronomy, Punjab Agricultural University, Ludhiana during rabi 2013–14 to study the bio-efficacy of two new brand formulations-Penda 30 EC and Markpendi 30 EC for control of Phalaris minor in wheat. New brand formulations of pendimethalin (Penda 30 EC and Markpendi 30 EC) @ 2.5 l/ha were tested against recommended brand formulation (Stomp 30 EC) @ 2.5 l/ha and unsprayed check in randomized block design in three replications. The tested new brand formulations of pendimethalin (Markpendi 30 EC and Penda 30 EC) were at par to earlier recommended brand (Stomp 30 EC) with respect to weed population, dry matter accumulation and wheat grain yield.

Potato (Solanum tuberosum) is one of four major food crops in the world. Weed control is a major component in potato production and has been accomplished using different methods, including but not limited to the use of herbicides and straw mulch. A combination of preemergence herbicide and straw mulch may improve weed control; however, no information is available for combining both methods, along with their effects on weed control, weed density, and potato tuber yields. The objective of this study was to evaluate weed control in potato using atrazine or straw mulch applied alone at different rates or in combination. A field experiment was conducted for 4 years from 2006 to 2010 in Ludhiana, Punjab, India. Common weeds included burclover (Medicago arabica), common lambsquarters (Chenopodium album), littleseed canarygrass (Phalaris minor), purple nutsedge (Cyperus rotundus), scarlet pimpernel (Anagallis arvensis), swinecress (Coronopus didymus), and toothed dock (Rumex dentatus). Results suggested that atrazine applied alone was not very effective and resulted in 0% to 78% control depending on the weed species being investigated at 30 days after treatment (DAT). Straw mulch applied alone at any rate provided ≥90% control of toothed dock, but control of other weed species was variable. A combination of atrazine and straw mulch at any rate usually resulted in >90% weed control at 30 DAT, except for swinecress and purple nutsedge. This treatment combination also resulted in weed density as low as 0 plant/m2 for common lambsquarters, scarlet pimpernel, and toothed dock. Potato tuber weight and yield was significantly higher in all treatments compared with untreated control without difference among them. It is concluded that a combination of straw mulch and atrazine can provide effective weed control in potato.