Weed-free Treatment Research Articles

Effects of neighbouring vegetation on planted indigenous tree establishment in modified environments: a New Zealand case study

Large-scale tree planting with indigenous trees is one approach to combatting climate change and environmental degradation. However, a significant challenge with establishing planted indigenous forests at scale, particularly in New Zealand, is that our knowledge and capacity to achieve this in highly modified environments, covered by invasive species, is relatively poor. The purpose of our study was to quantify the survival and growth of five indigenous tree species (three gymnosperms, two angiosperms) planted either on their own (weed-free) or in association with an indigenous (Leptospermum scoparium J.R. Forst) or exotic (Cytisus scoparius (L.) Link) shrub species. We monitored survival and growth following planting for 2.5 years. Results showed that survival for the gymnosperms was > 90% for all treatments. In contrast, survival of the two angiosperms was poor, and, in general, not significantly related to the presence or absence of neighbouring vegetation. The response to vegetation management for tree height was similar across all species: weed-free treatment > L. scoparium treatment > C. scoparius treatment. Diameter growth was also highest for all tree species in the weed-free treatment, compared to the two other vegetation management treatments, but the extent of the increase varied by tree species. We found no direct evidence for neighbouring vegetation facilitating early survival and growth of the five indigenous tree species tested at our study site. However, the outcomes require testing at scale and across environments to underpin future forest restoration efforts.

Influence of Different Nitrogen Levels and Weed Management Practices on Leaf Area Index of Dry Direct Seeded Rice (Oryza sativa L.) Under Temperate Conditions

Dry direct-seeded rice (DDSR) is an increasingly important cultivation method in regions facing water scarcity and labour constraints. Optimizing nitrogen application is instrumental in determining the environmental sustainability and economic feasibility of a farming system, making its management a top priority. In addition, the weed problems in dry direct-seeded rice account for the yield reduction and diminish the market value by reducing the product quality and raising the postharvest cost. Considering this, the present investigation was accomplished at MRCFC, SKUAST-K, Khudwani during Kharif 2022 and 2023. The experiment encircled the employment of four nitrogen levels: 0 kg N ha-1(N0), 60 kg N ha-1 (N1), 120 kg N ha-1 (N2), and 150 kg N ha-1 (N3). Additionally, seven weed management practices were employed encircling Pendimethalin at 1 kg ha-1 (3-4 DAS) + 2,4-D at 0.75 kg ha-1 (20 DAS), penoxsulam at 22.5 g ha-1 (12-15 DAS), Pyrazosulfuron combined with Pretilachlor at 30 g + 0.75 g ha-1 (3-4 DAS), Bensulfuron Methyl combined with Pretilachlor at 30 g + 0.75 g ha-1 (3-4 DAS), and Triafamone combined with Ethoxysulfuron at 40 g + 20 g ha-1 (12-15 DAS). The treatments also included a weedy check and a weed-free control. The experiment was designed in line with the factorial randomized complete block design (RCBD) possessing three replications. The acquired results elucidated a considerable increase in growth attributes such as leaf area index in response to various nitrogen levels as well as weed management approaches. Employment of nitrogen @ 150 kg ha-1 and Triafamone + Ethoxysulfuron (40+20 g ha-1) application, in addition to weed-free treatment, recorded the highest values for Leaf area index during 2022 and 2023.

Impact of Integrated Weed Management Strategies on Weed Density and Biomass in Rice (Oryza sativa L.)

To assess the effectiveness of various weed management practices on controlling weed density and dry weight in rice (Oryza sativa L.). A field experiment was carried out during 2022 and 2023 at the Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, in the Indo-Gangetic plains In Randomized Block Design (RBD) with 12 treatments, each replicated thrice. The treatments included a weedy check, a weed-free condition, farmer’s practice of one hand weeding at 40 days after transplanting (DAT), Pyrazosulfuron applied at 150 g ai ha-1 as a pre-emergence herbicide, Pyrazosulfuron 150 gm ai ha-1 followed by one hand weeding at 40 DAT, Bispyribac sodium at 25 g ai ha-1 applied 15 days after transplanting as a post-emergence herbicide, Bispyribac sodium at 25 g ai ha-1 followed by one hand weeding at 40 DAT, Ethoxy sulfuron applied at 20 g ai ha-1 as a pre-emergence herbicide, Ethoxy sulfuron 20 gm active ingredient per hectare followed by one hand weeding at 40 DAT, Penoxsulam applied at 22 g ai ha-1as a post-emergence herbicide, Penoxsulam 22 g active ingredient per hectare followed by one hand weeding, and a combination of Pyrazosulfuron 150 gm active ingredient per hectare as pre-emergence, followed by Penoxsulam 22 g ai ha-1 as post-emergence, and one hand weeding at 40 DAT. Weed density and dry weight were recorded at 30, 60, and 90 days after transplanting using quadrat sampling. The weed-free treatment consistently exhibited the lowest weed density and dry weight across both years, whereas the untreated weedy check resulted in the highest weed density and dry weight throughout the study. Among the herbicide treatments, the combination of Pyrazosulfuron and Penoxsulam with one hand weeding was found to be the most effective in significantly reducing weed density and dry weight.

Herbicide and irrigation management options in conventionally-tilled wheat: deciphering water and energy budgeting, and grain and monetary output in north-Indian plains

In South Asia, declining water tables due to increased irrigation and labor shortages for manual weeding pose significant challenges for wheat production. Additionally, herbicide resistance, often resulting from poor management practices, further complicates weed problems. The objective of this study was to assess the impacts of traditional irrigation regimens (IRs) and herbicide application on wheat crops. The findings showed that when irrigation was applied at 100 mm CPE (IR4), and at 40 mm CPE (IR1), different combinations of herbicide to weed managment were tested. In comparison to the other treatments, application of irrigation at 40 mm cumulative pan evaporation (IR1) along with the Pendimethalin1000 g ha−1 (pre-em) in combination with clodinafop-propargyl 10% + metribuzin 22% + sulfosulfuron 4.2% at a rate of 1125 g ha−1 at 30 DAS (WM1) produced the best results in terms of crop yields, economic returns, relative water content, consumptive use, rate of water use, water use efficiency, water productivity, energy input–output, energy returns, energy productivity, energy intensity, specific energy, energy efficiency, maximum field capacity, available soil water, and soil profile moisture extraction pattern. The only exceptions were Pendimethalin1000g ha−1 (pre-em) combined with carfentrazone ethyl 20% + sulfosulfuron 25%WG), at the rate of 100 g ha−1 at 30 DAS (WM2) and the weed-free treatment (WM5), where the differences were not statistically significant. The yield of wheat grain (14.26 kg ha−1) and straw (14.41 kg ha−1) decreased as the unit dry matter production of weeds increased. The study recommends exploring additional weed control strategies and irrigation management options in future improve wheat yields in conventionally-tilled systems.

Effect of herbicide and varying rates of straw mulching on weed dynamics, productivity and profitability of rice

In kharif 2022 and 2023 a field study was conducted in randomized complete block design with three replications for evaluating eleven treatments comprised of sole application of pendimethalin (750 g/ha) and bispyribac- Na (25 g/ha), rice straw mulch (RSM) (4, 6 and 8 t/ha), combination of pendimethalin along with variable rates of RSM, sequential application of pendimethalin fb bispyribac-Na and compared with weed free and weedy check. The study revealed that among the herbicidal and straw mulching treatments, the application of pendimethalin fb RSM 8 t/ha registered significantly the minimum density and biomass of total and all categories of weeds, except broad leaved weeds (BLWs) at 45 DAS. However, it was followed by the application of pendimethalin fb RSW 6 t/ha and pendimethalin fb bispyribac-Na application. The weed-free treatment registered the maximum weed control efficiency (WCE) and the minimum density and biomass of broad-leaved weeds, which was at par with pendimethalin fb bispyribac-Na treatment. Weed-free plot produced the maximum grain yield of 3.98 t/ha, which was at par with the application of pendimethalin fb straw mulching at 8t/ha (3.86 t/ha), pendimethalin fb bispyribac-Na (3.77 t/ha) and pendimethalin fb straw mulching at 6 t/ha (3.74 t/ha) treatments. Further, economic analysis revealed that the sequential application pendimethalin 750 g/ha (Pre) fb bispyribac-Na 25 g/ha (Post) fetch maximum net return (Rs.45,282/ha), which was followed by the integration of pendimethalin 750 g/ha fb RSM 6 t/ha (Rs.31,056/ha) in DSR. These treatments could manage the diverse weed flora and obtain higher grain yield and more significant profit in direct-seeded rice.

Use of a capsule suspension formulation of S-metolachlor in fenclorim-treated rice

Abstract As herbicide resistance continues to render commonly used rice herbicides ineffective, alternative sites of action are paramount to maintaining yield and producer profitability. Combining a slow-release formulation and a fenclorim seed treatment might allow the safe use of S-metolachlor in rice. Experiments were initiated in 2022 and 2023 near Colt, AR, on a silt loam soil to evaluate crop safety using a capsule suspension (CS) formulation of S-metolachlor and a fenclorim seed treatment in rice. The first experiment assessed the tolerance of two cultivars (‘Diamond’ and ‘DG263L’) to three rates (0.42, 0.84, and 1.68 kg ai ha−1) of a CS S-metolachlor at a delayed preemergence (DPRE) application timing in conjunction with a fenclorim seed treatment. The second experiment evaluated a 1- to 2-leaf (EPOST) application of a CS S-metolachlor at 0.56 and 1.12 kg ai ha−1 to fenclorim-treated rice. Fenclorim reduced injury and partially protected rice yield when S-metolachlor was applied DPRE at 1.68 kg ai ha−1 in both years. However, in one year, under adverse conditions, rice yields were only 65% and 66% of the nontreated control for fenclorim-treated ‘Diamond’ and ‘DG263L’, respectively. An EPOST application of S-metolachlor at 1.12 kg ai ha−1 resulted in 44% to 51% visible injury 35 d after treatment. Relative rice yields were 88% and 89% of the nontreated weed-free treatment in 2022 and 2023, respectively. Fenclorim provided enhanced crop safety at both the 0.84 and 1.68 kg ai ha−1 rates of S-metolachlor. However, the potential for reduced yield can arise when unfavorable conditions occur soon after application. An EPOST application timing of CS S-metolachlor at 0.56 kg ai ha−1 may be a viable option in rice, but 1.12 kg ai ha−1 is too high on a silt loam soil, resulting in significant rice injury.

Efficacy of Pre and Post Emergence Herbicides against Complex Weed Flora, Yield and Economics of Blackgram under High Hills Wet Temperate Zone of Himachal Pradesh

Background: Implementing integrated strategies for weed management is essential in maximizing blackgram yield. Unchecked weed proliferation leads to substantial decrease in crop productivity. Methods: The current field experiment was conducted at Salooni, Himachal Pradesh, to evaluate the efficacy of different integrated weed management practices during Kharif 2022 and 2023. Eleven treatments targeting weed control were evaluated both at pre and post - emergence stages. Result: The predominant weeds were Echinochloa colona, Galinsoga parviflora, Cyperus species and other broad leaf weeds were Plantago lanceolata, Trifolium repens, Trianthema species, Ageratum conyzoides. Data on weed dynamics revealed that; after weed-free treatment, the application of Imazethapyr 75 g/ha as PE fb HW at 30 DAS; Pendimethalin 1.0 kg/ha as PE fb HW at 30 DAS and Pendimethalin 1.0 kg/ha + imazethapyr 75 g/ha (PE) recorded a significantly lower total weed count as compared to other treatments. Parameters related to blackgram growth and yield, including plant height, number of branches per plant, pods per plant, grain yield and haulm yield were significantly higher with weed-free treatment followed by application of imazethapyr 75 g/ha as PE fb HW at 30 DAS, remaining at par with application of pendimethalin 1.0 kg/ha + imazethapyr 75 g/ha (PE) and pendimethalin 1.0 kg/ha as PE fb HW at 30 DAS. The most economically efficient weed control method was the combination of pendimethalin 1.0 kg/ha + imazethapyr 75 g/ha (PE), as it resulted in the highest net returns and marginal benefit-cost ratio.

Effect of Different Herbicides on Weed Dynamics in Wheat (Triticum aestivum L.)

A field experiment was conducted at Research farm, Vivekananda Global University, Jaipur during Rabi, 2023 on loamy sand soil. The experiment comprises 11 treatments of weed management practices in wheat (Weedy check, Weed free, Hand weeding at 30-35 DAS, 2,4-D ester @ 0.75 kg/ha at 30-35 DAS, Sulfosulfuron @ 25 g a.i. at 30-35 DAS, Carfentrazone ethyl @20 g/ha at 30-35 DAS, Metsulfuron methyl @ 4 g/ha at 30-35 DAS, Pinoxaden @60 g a.i./ha 25-30 DAS, Piroxofop- propargyl 15% WP @60g a.i./ha 30-35 DAS, Sulfosulfuron 75% + Metsulfuron 5% WG @ 32g a.i./ha at 30-35 DAS and Clodinafop-propargyl 15% + Metsulfuron methyl 1% @ 32 g a.i./ha at 30-35 DAS) thereby experiment was laid out in randomized block design and replicated thrice. Results showed that application of Sulfosulfuron 75% + Metsulfuron 5% WG @ 32g a.i./ha at 30-35 DAS at 30-35 DAS treatment resulted significant reduction in weed density, weed dry matter in comparison to most of the treatments while highest weed control efficiency and lowest weed index was recorded with the same treatment except weed free treatment. Clodinafop-propargyl 15% + Metsulfuron methyl 1% @ 32 g a.i./ha at 30-35 DAS was next superior treatment.

The Impact of Integrated Weed Management Practices on Nutrient Uptake in Rice (Oryza sativa L.)

The study investigated the impact of integrated weed management practices on nutrient uptake in rice (Oryza sativa L.) and weeds at 90 days after transplanting (DAT) over the 2022 and 2023 growing seasons at the Crop Research Centre (CRC) farm of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut. Various weed control strategies, including the application of pre-emergence and post-emergence herbicides combined with manual weeding, were evaluated for their effectiveness in enhancing the uptake of essential nutrients such as nitrogen (N), phosphorus (P), and potassium (K) by rice, while also reducing nutrient loss to weeds. Among the strategies tested, the combination of Pyrazosulfuron at 150 g active ingredient per hectare (a.i. ha⁻¹) as a pre-emergence herbicide and Penoxsulam at 22 g a.i. ha⁻¹ as a post-emergence herbicide, supplemented with one manual weeding at 40 DAT, proved to be the most effective. This approach resulted in the highest nutrient uptake by rice and the lowest nutrient uptake by weeds. In this treatment, nitrogen uptake in the rice grains reached 62.7 kg per hectare in 2022 and 67.4 kg per hectare in 2023, significantly outperforming other treatments. The weed-free treatment, which involved complete weed eradication, also demonstrated high nutrient absorption, highlighting the importance of thorough weed control for optimal rice growth. Conversely, the untreated weedy check, where no weed control was implemented, led to the highest nutrient uptake by weeds, severely limiting the availability of nutrients for the rice crop. Manual weeding alone, without the use of herbicides, showed moderate effectiveness but was less efficient compared to the integrated approach combining herbicides and hand weeding.

Intercomparison of Different Agrochemicals (Herbicides) and Manual Methods of Weed Control on Weed Population and Weed Control Efficiency in Wheat (Triticum aestivum L.) Crop in Himachal Pradesh Dist

Aims: A research study entitled Intercomparison of different Agrochemicals (Herbicides) and manual methods of weed control on weed population and weed control efficiency in wheat crop (Triticum aestivum L.) in Himachal Pradesh district Mandi. Study Design: The experiment was designed using a Randomized Block design method. Place and Duration of Study: Department of agronomy, School of Agriculture, Abhilashi university, Chail Chowk, Mandi, (H.P.) during the Rabi season of 2022-23. Methodology: The field trail was conducted with eight treatments and replicated thrice. The investigation included eight different weed control techniques i.e. T1 -weedy check, T2 - weed free, T3 - hand weeding at 30 DAS, T4 - 2, 4-D @ 0.5 kg a.i. ha-1 + Sulfosulfuron @ 0.02 kg a.i. ha-1 at 30 DAS,T5 - Pendimethalin @ 1.5 kg a.i. ha-1(P.E) + Quizalofop-ethyl @ 50 gm a.i ha-1 (PoE at 25 DAS) + one hand weeding, T6 - 2, 4-D @ 0.5 kg a.i. ha-1, T7 - 2, 4-D @ 0.5 kg a.i. ha-1 + one hand weeding at 30 DAS, T8 - 2, 4-D @ 0.5 kg a.i. ha-1 + two hand weeding at 30 and 45 DAS. Results: The investigation found that the most effective ways to control weeds are by keeping the area completely weed free by using pendimethalin @ 1.5 kg a.i. ha-1(P.E) + Quizalofop-ethyl @ 50 gm a.i ha-1(PoE at 25 DAS) + one Hand weeding (Treatment T2) was found the most successful in terms of achieving the lowest weed density and highest weed control efficiency. Application of pendimethalin @ 1.5 kg a.i. ha-1(P.E) + Quizalofop-ethyl @ 50 gm a.i ha-1 (PoE at 25 DAS) + one hand weeding was found to be better than using herbicides to reduce weed infestation in wheat crops. Conclusion: Based on the results, it can be concluded that integrated weed management practices weed-free treatment was the most effective option for managing weeds in wheat.

Investigating the Effectiveness of Various Weed Control Methods to Reduce Narrow and Broad Leaf Populations in the Oat (Avena sativa L.) Crop

Aims: It is aim to investigating the effectiveness of various weed control methods to reduce narrow and broad leaf populations in oat (Avena sativa L.) crop. Study Design: The experiment was designed using a Randomized Block design method. Place and Duration of Study: Department of agronomy, School of Agriculture, Abhilashi university, Chail Chowk, Mandi, India (H.P.) during the Rabi season of 2022. Methodology: The field trail was conducted with seven treatments and replicated thrice. The investigation included seven different weed control techniques i.e. T1 - weedy check (control), T2 - weed free, T3 - one hand weeding at 25 DAS, T4 - two hand weeding at 25 DAS and 45 DAS,T5 - pre-emergence application of Pendimethalin @ 0.75 kg a.i. ha-1 + one hand weeding at 25 DAS, T6 - post emergence application of atrazine @ 0.75 kg a.i. ha -1 at 35 DAS + one hand weeding at 25 DAS, T7 - post emergence metsulfuron methyl @ 0.004 kg a.i. ha -1 at 35 DAS + one hand weeding at 25 DAS. Results: The investigation found that the most effective ways to control weeds are by keeping the area completely weed-free or by using two-hand weeding at 25 DAS and 45 DAS. T2 (weed-free), which involved keeping the area weed-free, was found to be the most successful in terms of achieving the lowest weed density and highest weed control efficiency. Two-hand weeding at 25 DAS and 45 DAS was found to be better than using herbicides to reduce weed infestation in oat crops. Conclusion: Based on the results, it can be concluded that integrated weed management practices weed-free treatment is the most effective option for managing weeds in oats.

Bio-Efficacy of Pre-and Post-Emergence Herbicides on Growth, Productivity, Nodulation of Black Gram (Vigna mungo L.) under Coastal Plain of Odisha

Background: Weeds compete with plants for resources during cultivation and the control of weeds during the critical period of crop-weed competition is crucial to avoid yield loss ranging from 50%-90% in black gram. The first 4-5 weeks are critical for black gram crop-weed competition. The composition of weed flora, the duration of crop-weed competition and its intensity significantly impact yield losses in black gram cultivation. Therefore, the current study aims to evaluate weed management practices in rabi black gram, with a focus on identifying herbicides that enhance weed control, increase productivity and profitability. Methods: A field experiment was conducted during the rabi season of 2021-2022 and 2022-2023 consecutively at Odisha University of Agriculture and Technology, Bhubaneswar. The field experiment comprised of eight treatments on different herbicide applications as T1- Fenoxaprop-p-ethyl @ 65 g a.i. ha-1, T2- Quizalofop-p-ethyl @ 50 g a.i. ha-1, T3-Cyhalofop-butyl @ 75 g a.i. ha-1, T4-Pendimethalin @ 750 g a.i. ha-1, T5- Oxyflourfen @ 50 g a.i. ha-1, T6- Tembotrione @ 120 g a.i. ha-1, T7- Weed check (control) and T8- Weed free, which was laid under randomised block design. Collected samples were analyzed in the field and laboratory for crop-weed competition, herbicide phytotoxicity and yield attributes. Result: The results revealed that weed-free treatment recorded the lowest weed population (5.27-5.45), weed dry weight (1.35g-2.20 g) and lowest weed index (0.00%) at all growth stages followed by pendimethalin (PE) application. Among yield attributes, weed-free treatment recorded the highest plant height (cm) which was at par with pendimethalin (PE) followed by cyhalofop-butyl (PoE) application. The magnitude of seed yield was increased under weed-free (1035.46 kg ha-1) and pendimethalin (PE) and cyhalofop-butyl (PoE) applications by 53.62% and 48.40%, respectively over the weedy check. Application of tembotrione recorded the highest herbicide phytotoxicity (5.3-7.6) over the rest of the treatments. It can be concluded that the application of pendimethalin 30 EC 750 g ha-1 as PE at 2 DAS followed by cyhalofop-butyl 10 EC 75 g ha-1 can be advisable for better weed control, lower herbicide phytotoxicity and higher yield.

Does weed infestation alter the population density of harmful leafhopper species in second crop maize?

Weed-insect interaction has been studied for decades to determine the role of weeds in insect infestation. This study investigated the impact of weed density on the population density of important leafhopper species (Cicadellidae: Hemiptera) and their egg parasitoid Anagrus atomus (L.) (Hymenoptera: Chalcidoidea) in maize (Zea mays L.) planted as second crop in Şanlıurfa province, Türkiye during 2022 and 2023. Population densities of harmful leafhopper species, i.e., Zyginidia sohrab (Zachvatkin), Empoasca decipiens (Paoli), Asymmetrasca decedens (Paoli), Psammotettix striatus (Linnaeus), and their parasitoid, i.e. A. atomus were monitored by yellow sticky traps (RAL-1016) under weedy and weed-free conditions. Three traps were hung in each experimental unit and the densities of target species were recorded weekly. The population densities of leafhopper species feeding on Sorghum halepense (L.) (Johnsongrass) and the effect of A. atomus on their population density were also determined in weedy treatment. A total 15 maize leaves were taken from both weedy and weed-free treatments, and S. halepense leaf tissues containing leafhopper eggs parasitized by A. atomus were counted weekly. Weed density had non-significant effect on the population density of Z. sohrab during both years. Contrastingly, increasing weed density increased the population density of E. decipiens & A. decedens complex in 2022. Nevertheless, weed density had non-significant effect on the population density of E. decipiens & A. decedens complex during 2023. Weedy treatment recorded higher population density of P. striatus (140 and 100 adults, respectively); however, both weedy and weed-free treatments recorded similar density (125 and 97 adults) during 2023. Weed density proved a significant factor in increasing A. atomus density. A total of 2935 parasitized eggs were recorded from the weedy treatment, whereas 1609 parasitized eggs were recorded from weed-free treatment. Although direct relationship between leafhoppers and weed density remains uncertain, integrated pest management strategies must consider phytophagous insects feeding on weeds at field edges and within fields and the natural enemy complex.

Bio-Efficacy Evaluation of Herbicides for Weed Management in Rabi Onion

A field experiment entitled “Bio-efficacy evaluation of herbicides for weed management in rabi onion” was conducted at Weed Control Research Farm, Department of Agronomy, College of Agriculture, Junagadh Agricultural University, Junagadh (Gujarat) during the rabi season of 2021-22 on medium black calcareous soil. The experiment comprising 14 treatments was laid out in a randomized block design with three replications. The results revealed that next to weed-free treatment, tank-mix pendimethalin 450 g/ha + oxyfluorfen 120 g/ha as pre-planting fb HW at 40 DATP, tank-mix pendimethalin 450 g/ha + oxyfluorfen 120 g/ha as pre-planting fb pre-mix propaquizafop + oxyfluorfen 43.75+105 g/ha at 40 DATP and tank-mix pendimethalin 450 g/ha + oxyfluorfen 120 g/ha as pre-planting fb pre-mix quizalofop + oxyfluorfen 100 g/ha at 40 DATP control of complex weed flora, reduced population and dry matter of weeds and having less reduction in yield due to better control of weeds, less crop-weed competition, higher weed control efficiency.

Effect of Planting Patterns and Weed Competition on Growth, Yield and Quality of Wheat (Triticum aestivum L.)

Background: A study was done during the Rabi 2022-23 on the farm of Lovely Professional University, Phagwara (Punjab) on “Effect of planting patterns, weed competition on growth, yield and quality of wheat (Triticum aestivum L.).” PBW-824 variety was used for the experiment which is suitable under irrigated conditions of Punjab. Methods: The experiment was conducted in split plot design (SPD) with 4 planting techniques viz. two rows per bed, three rows/bed, bidirectional sowing, flat/line sowing in main/major plots and four weed competition treatments viz. competition by Phalaris minor only, competition by broad leaf weeds only, competition by both (weedy check) and no competition (weed free) in minor/sub plots. Result: The findings concluded that among main plots, crucially more grain yield (51.93 q/ha) and (51.29 q/ha) was obtained in cross sowing and three rows/bed, than two rows/bed and flat/line sowing pattern. Also increased seed/kernel yield in cross sowing, three rows/bed and two rows/bed was (14.43%, 13.02% and 5.39%) respectively than flat sowing. The growth and yield attributes were also seriously more in cross sowing, three rows per bed than flat sowing. Among weed competition treatments grain yield was significantly higher in no competition by both Phalaris minor and broad leaf weeds than other weed competition treatments. There were 41.85%, 25.55% and 14.75% increased grain yield in no competition treatment, competition by broad leaf weeds only and competition by Phalaris minor only as compared to control (unweeded) treatment. Among sub plots, all yield attributes were significantly higher in weed free treatment as contrast to all other weed competition treatments.

Yield, Yield Attributes and Weed Biomass of Rice (Oryza sativa L) as Influenced by Weed Control Treatments

The present investigation was conducted during the Kharif of 2019 at Research cum Instructional Farm, Indira Gandhi Krishi Vishwavidyalaya, Raipur, Chhattisgarh. The experiment was laid out in randomized complete block design (RCBD) with three replications and ten weed management treatments viz. Pretilachlor (PE )750 g ha-1 , BispyribacNa (PoE ) 25 g ha-1 , Fenoxaprop-p-ethy (PoE) l 56.25 g ha-1 , Cyhalofop-buty (PoE ) l 80 g ha-1 ,Penoxsulam+ Cyhalofop butyl (PoE ) 135 g ha-1, Penoxsulam(PoE ) 22.5 g ha-1 , Metsulfuronmethy ( early PoE ) l 4 g ha-1 , 2,4-D Ethyl Ester (PoE ) 750 g ha-1 ), weed free (HW) , at 20, 40 and 60 days after sowing and weedy check . Result was found that among the weed management treatments, the weed free treatment registered significantly highest value and was at par the application of Penoxsulam+ Cyhalofop butyl 135 g ha-1 , yield attributing characters, grain and straw yield and dry matter of Alternanthera sessilis it was found the lowest value in the application of Penoxsulam+ Cyhalofop butyl 135 g ha-1 (T5).

Conservation agriculture and weed management effects on weed community and crop productivity of a rice-maize rotation

In recent years, an increase in weed infestation, which is adversely affecting crop growth and productivity has been a major challenge facing the farmers of South Asia. The adoption of a permanent bed in combination with residue retention-based crop management practices may reduce weed abundance and increase crop productivity. In a two-year field study, we evaluated the responses of different organic weed management practices with contrasting tillage and residue (R) management strategies to weed dynamics and crop productivity under rice-maize rotation. The main plot treatments consisted of zero-tillage direct seeded rice and zero-tillage maize (ZTR fb ZTM); ZTDSR and maize both on permanent raised beds with residue (PBDSR + R fb PBDSM + R); PBDSR and PBM without residue (PBDSR-R fb PBDSM-R) and conventional tillage puddled transplanted rice and conventional tillage maize (CTR fb CTM). The subplots comprised unweeded control; vermicompost mulch; P- enriched vermicompost mulch; live mulch with Sesbania spp. in rice and Pisum sativum in maize and weed-free. Total weed density and biomass in rice and maize at 30 days after sowing (DAS) were minimum for PBDSR + R fb PBDSM + R compared to remaining tillage and residue management practices in both years. Apart from weed-free treatment, the highest weed control index was found with live mulch. Yield of rice and maize were found higher in permanent beds along with residue retention-based practices. In rice, the weed-free treatment showed the highest grain yield and live mulch reported 9.8 and 6.8 % higher grain yield than vermicompost mulch and P-enriched vermicompost mulch respectively. Our study shows that conservation agriculture practices under rice-maize rotation is one of the ways to reduce weed density and improve crop productivity in South Asia and other similar agro-ecologies.

Chemical weed management in wheat (Triticum aestivum) using ready-mix and tank-mix herbicides

A field experiment was conducted at the Bichpuri, Agra, Uttar Pradesh during the winter (rabi) seasons of 2011–12 and 2012–13, to evaluate the effect of different grass and broad-leaf herbicides as sole and ready-mix application on weed control in wheat (Triticum aestivum L.). Ready-mix application of herbicides proved better than their alone application in suppressing weed number and dry weight. Application of sulfosulfuron + metsulfuron (25 + 4 g/ha) resulted in the highest weed-control efficiency (WCE) as well as herbicide efficiency (HEI) and lowest weed index of 94.8%, 2.97 and 3.3 respectively. The highest grain and stover yield of 4.05 and 6.39 t/ha were obtained from weed-free treatment, although this remained statistically at par with sulfosulfuron + metsulfuron (25 + 4 g/ha) and both the treatments resulted in an increase of 34.6 and 30.2% in grain yield as compared to weedy check respectively. The highest net returns ( 43,200/ha) and benefit: cost ratio (2.40) were obtained with ready-mix application sulfosulfuron metsulfuron (25 + 4 g/ha) among the tested herbicide treatments.

Effect of Different Doses of Herbicides on Growth and Yield in Maize (Zea mays L.)

A field experiment was conducted at Chandra Shekhar Azad University of Agriculture and Technology, Kanpur during Kharif season of 2021, to evaluate effect of different doses of Mesotrione 2.27% w/w + Atrazine 22.7% w/w SC on growth and yield of maize (Zea mays L.). The experiment was laid down in the Randomized block design with ten treatments which was replicated three times. At 45, 60 and 90 DAS among different herbicidal treatments maximum plant height was observed in Mesotrione 2.27% w/w + Atrazine 22.7% w/w SC) @ 1.0 kg a.i. ha-1. Among the herbicidal treatments, highest cob length (15.67 cm), grain rows per cob (13.26), grains per row (26.93) and grains per cob (370.83) was observed in the treatment T4 (Mesotrione 2.27% w/w + Atrazine 22.7% w/w SC) @ 1.0 kg a.i. ha-1) followed by treatment T3 (Mesotrione 2.27% w/w + Atrazine 22.7% w/w SC) @ 0.875 kg a.i. ha-1). Data from experiment revealed that significantly highest grain yield was recorded in weed free plot (35.65 q ha-1). While among herbicidal treatments, application of Mesotrione 2.27% w/w + Atrazine 22.7% w/w SC @ 1.0 kg a.i. ha-1 (35.18) resulted in significantly higher grain yield followed by (T3) Mesotrione 2.27% w/w + Atrazine 22.7% w/w SC @ 0.875 kg a.i. ha-1 (34.38 q ha-1). Among all the treatments all the parameters of crop growth and yield was highest in the weed free treatment (T9).

Influence of Different Herbicides on the Growth, Growth Attributes and Yield of Maize (Zea mays L.) under Central Plains Zone of Uttar Pradesh

The field experiment was carried out at Agriculture Research Farm, Integral University, Lucknow, Uttar Pradesh, India during Kharif, 2021. The experiment was aimed at studying the effect of herbicides on the growth and yield of maize crop. The experiment was laid down in the Randomized Block Design (RBD) with 12 treatments and was replicated three times. The highest plant height was observed in weed free treatment due to weed free environment all over the maize growth period but among the herbicides, treatment(T8) Atrazine @ 0.5 kg a.i. ha-1 PE followed by Tembotrione @ 0.120 kg a.i. ha-1 PoE at 20 DAS showed highest plant height of 115.2 cm, 173.63 cm and 226.29 cm at 40 DAS, 60 DAS and at harvest stage, respectively. The same treatment (T8) also resulted in the highest number of leaves per plant. The highest cob weight per plant, grain weight per cob, number of seed per cob and test weight of 219.23 g, 144.1 g, 579.23 and 27.43 g, respectively was observed in the same treatment (T­8). The highest grain yield (5199 kg ha-1) was observed in the weed free treatment but among the herbicidal treatment, the treatment T8 obtained the highest grain yield of 4803 kg ha-1 and was at par with the treatment (T7) Atrazine @ 0.5 kg a.i. ha-1 fb 2,4-D sodium salt @ 0.5 kg a.i. ha-1 PoE at 30 DAS bearing grain yield of 4723 kg ha-1. Among the herbicidal treatments, the treatment (T8) also resulted in the highest biological yield (12042 kg ha-1) and Harvest index (39.89%) which was at par with the treatment Atrazine @ 0.5 kg a.i. ha-1 PE followed by 2,4-D sodium salt @ 0.8 kg a.i. ha-1 PoE at 30 DAS (T7).