Weed Dry Weight Research Articles

Evaluation of Allelopathy of Agricultural Land Associated Trees on Weed Growth and Yield Performance of Boro Rice

We conducted an experiment at the Agronomy Field Laboratory, BAU, Mymensingh to evaluate the allelopathic effect of Mangifera indica, Artocarpus heterophyllus, Albizia lebbeck and Shorea robusta on the weed growth and yield performance of boro rice. The experiment consisted of one cultivar i.e. BRRI dhan29 and five different extract’s treatments such as no leaf extracts (T1), Mangifera indica leaf extracts(T2), Artocarpus heterophyllus leaf extracts(T3), Albizia lebbeck leaf extracts (T4) and Shorea robusta leaves extract (T5) @20:200 (w/v) ratio concentration. The experiment was laid out in a Completely Randomized Design with four replications. Weed population, weed dry weight were significantly affected by different treatments. The highest weed population and dry weight for all weed species were found in no tree leaf extracts treatments (T1) and Shorea robusta leaf extracts (T2) respectively. The lowest weed population and weed dry weight were recorded in Artocarpus heterophyllus leaf extracts (T3). The highest grain yield as well as the yield contributing characters was recorded in Albizia lebbeck leaf extracts (T4). The highest reduction of grain yield was observed in T1 (no tree leaf extracts) treatment. The longest plant height, highest number of total tiller hill-1, highest number of effective tillers hill-1, number of grains panicle-1, 1000-grain weight, grain and straw yields were observed in Albizia lebbeck leaf extracts (T4) treatment and the lowest was observed in T1. Results of this study indicates that Artocarpus heterophyllus (T3) and Albizia lebbeck (T4) leaf extracts showed potentiality in yield contributing characters of Boro rice. Therefore, Artocarpus heterophyllus and Albizia lebbeck leaf extracts might be used as an alternative way for weed management and sustainable crop production.

A comparative study of drone and manual herbicide application for weed management in wet direct-seeded rice (Oryza sativa L.)

A field experiment was conducted at Tamil Nadu Agricultural University, Coimbatore, during the Navarai season (January-April) of 2024 to assess the efficiency of drone-based herbicide application in terms of weed control, energy use, and cost effectiveness in wet direct-seeded rice (Oryza sativa L.). The study compared the effectiveness of weed control using herbicide combinations applied as pre-emergence followed by early post-emergence, with both drone and knapsack sprayer. The treatments included the application of pretilachlor followed by early post-emergence bispyribac sodium, and pyrazosulfuron followed by penoxsulam + cyhalofop butyl, using both drone and knapsack sprayer. Additionally, weed-free and unweeded control plots were included. Results indicated that the application of pretilachlor followed by bispyribac sodium using a drone sprayer significantly reduced weed density and weed dry weight compared to the unweeded plot. This treatment also resulted in a higher grain yield (5286 kg ha-1). Moreover, drone application of pretilachlor followed by bispyribac sodium provided a higher net return (? 51631/ha), benefit-cost ratio (2.17), energy-use efficiency (9.53), and energy productivity (0.30 kg/MJ). The experiment concluded that drone-based spraying of pretilachlor followed by bispyribac sodium is an effective weed management strategy for wet direct-seeded rice, offering superior yield attributes, energy use efficiency, and profitability.

Allelopathic Effects of Residues of Fimbristylis dichotoma Along with Manures and Fertilizers on the Weed Growth in Boro Rice

Currently, the rice-growing system seeks a biological solution to reduce the negative impacts of chemical herbicides because it is heavily reliant on these for weed control. This is where allelopathy comes in; it's a potential substitute for conventional weed management strategies in rice cultivation by making use of allelopathic plant residues. In the study we used Fimbristylis dichotoma residues with several organic sources of nutrient to measure the integrated effect of manures, fertilizers, and Fimbristylis dichotoma residues on weed growth in boro rice field. Two rice varieties viz., BRRI dhan29 and BRRI dhan89; and six treatments total viz., Control (T1), Residues @ 3 t ha-1 + Recommended doses of inorganic fertilizers (T2), Residues @ 3 t ha-1 + Tricho-compost @5 t ha-1 (T3), Residues @ 3 t ha-1 + Tricho-compost @1.5 t ha-1 + 25% less than recommended doses of inorganic fertilizers (T4), Residues @ 3 t ha-1 + Tricho-compost @2.5 t ha-1 + 50% less than recommended doses of inorganic fertilizers (T5) and Residues @ 3 t ha-1 + Tricho-compost @3.75 t ha-1 + 75% less than recommended doses of inorganic fertilizers (T6) were taken. In the experiment, at 25 DAT (days after transplanting), BRRI dhan89 had the highest weed density (35.0) when no residue was applied, and BRRI dhan29 had the lowest (18.00) when 3 t ha-1 F. dichotoma residue with Tricho-compost @ 1.5 t ha-1 + 25% less than recommended doses of inorganic fertilizers were applied. At 55 DAT, BRRI dhan89 had the highest weed density (19.66) when no residue was administered, and the lowest (10.66) when 3 t ha-1 F. dichotoma residue was applied along with Tricho-compost @ 1.5 t ha-1 + 25% less than recommended doses of inorganic fertilizers. When it came to dry weight, at 25 DAT, BRRI dhan89 had the highest weed dry weight (3.76 g) when no residue was applied, and BRRI dhan29 had the lowest (1.72 g) when 3 t ha-1 F. dichotoma residue with Tricho-compost @1.5 t ha-1 + 25% less than recommended doses of inorganic fertilizers were applied. At 55 DAT, BRRI dhan89 had the highest weed dry weight (2.29 g) when no residue was sprayed, and the lowest (1.46 g) when 3 t ha-1 F. dichotoma residue with Tricho-compost @ 1.5 t ha-1 + 25% less than recommended doses of inorganic fertilizers were applied. The study's findings suggest that applying F. dichotoma residue and incorporating Tricho-compost @ 1.5 t ha-1 + 25% less than the recommended amounts of inorganic fertilizers may be able to suppress the growth of weeds and could a package in biological weed control strategy.

Efficacy of various herbicides for weed management in irrigated chickpea (Cicer arietinum)

Chickpea is a short-stature crop with slow initial growth and limited leaf area development due to which it is heavily infested with a wide spectrum of weeds. The menace of weeds has increased to such an extent that an ef- fective weed management schedule has become a necessity. A research study was conducted during the rabi season of 2021–22 at the Agronomy Research Farm, Chaudhary Charan Singh Haryana Agricultural University, Hisar, Haryana. Thirteen weed control treatments viz., pre-plant incorporation (PPI) and pre-emergence (PRE) pendimethalin at 1,000 g/ha, PPI imazethapyr at 75 g/ha and 100 g/ha, PRE imazethapyr at 75 g/ha and 100 g/ha, post-emergence (PoE) imazethapyr at 75 g/ha and 100 g/ha, PPI and PRE pendimethalin + imazethapyr Ready mix (RM) at 1,000 g/h and two hand hoeings at 30 and 50 DAS were compared with weedy check and weed free in a randomized block design and replicated thrice. Among the herbicides, lowest weed dry weight was observed un- der PPI and PRE pendimethalin + imazethapyr (RM) at 1,000 g/ha respectively. PoE application of imazethapyr displayed phytotoxicity symptoms like stunting, leaf crinkling, and chlorosis as indicated by phytotoxicity scale ranging from 1-5. Significantly higher seed yield was obtained by pendimethalin + imazethapyr (1,827 kg/ha) over other combinations. Therefore, the PRE-application of pendimethalin + imazethapyr (RM) at 1,000 g/ha was the most suitable herbicide for efficient weed management in chickpea as it not only controlled the diverse weed flora but also improved seed yield.

Combined hot water extract of lentil and grass pea increase weed control efficiency and yield of boro rice

The agriculture sector is continuously adopting environmentally friendly and sustainable methods to reduce the harmful effects of herbicides on crop production. In this context, an experiment was conducted at the Agronomy Field Laboratory (AFL), Bangladesh Agricultural University (BAU), Mymensingh, from December 2021 to May 2022, to investigate the effect of combined hot water extracts of lentil and grass peas (ELG) on weed control efficiency and yield performance of boro rice. The experiment involved four varieties of boro rice (BAU dhan3, BRRI dhan28, BRRI dhan81, and BRRI dhan96) and four treatments of crop residues. For most weed species, varieties and crop residue extracts significantly impacted weed population (WP) and weed dry weight (DW). The highest numbers of effective tillers (NET) hill-1, numbers of spikelets panicle-1 (NSP), 1000-grain weight (TGW), grain yield (GY), and straw yield (SY) were observed in the three-times hand weeding treatment. This was followed by the combination of hot water ELG applied as a pre-emergence treatment three days after transplanting and post-emergence ten days after transplanting, with the lowest values found in the no-extract treatment. Considering interaction effects, the highest GY (7.07 t ha-1) and SY (8.23 t ha-1) were observed with hand weeding combined with the variety BAU dhan3. The results of this study indicated that hand weeding, followed by the combined application ELG crop residue, showed potential activity to suppress WP and significantly affected the yield of boro rice.

Herbicide evaluation in direct seeded rice in the middle Gangetic plains of India

AbstractA field experiment was conducted in Samastipur district of Bihar, India during kharif season of 2021 and 2022 to identify suitable herbicides for control of composite weed flora in direct seeded rice. Compared to weedy check, application of bispyribac sodium + pyrazosulfuron ethyl as tank mixture effectively reduced weed density at 50 days after seeding during both the cropping season (82% and 86%, respectively) and weed dry weight (7.62 and 7.18 g m−2, respectively) over control and as a result yielded maximum during both the cropping season (47.92 and 51.32 q ha−1, respectively). Based on overall performance, bispyribac sodium + pyrazosulfuron ethyl may be considered as viable weed management option in direct seeded rice for the rice growers of middle Indo‐Gangetic region.

Herbicidal and Nitrogen Efficacy on Weed Management in Wheat Fields of Eastern Uttar Pradesh, India

Weeds can significantly affect crop yield and nutrient uptake, making effective management crucial in wheat fields. This study, conducted during the winter (Rabi) season of 2018-19 at the Agricultural Research Farm of Banaras Hindu University in Varanasi, aimed to assess the combined impact of different nitrogen levels and herbicide treatments on weed control and wheat production. The objective was to determine the best practices for reducing weed competition and improving crop performance. The experiment was set up using a split plot design with three replications. The treatments comprised of 3 nitrogen levels and 5 weed control methods. The study identified nine prevalent weed species in wheat fields, including Phalaris minor, Anagallis arvensis, Cynodon dactylon, Chenopodium album, Melilotus indicus, Vicia sativa, Medicago denticulata, Solanum nigrum, and Cyperus rotundus, with Anagallis arvensis, Chenopodium album and Vicia sativa being the most dominant. The application of Sulfosulfuron (25 g ha-1) combined with 2, 4-D (750 ml ha-1) resulted in the lowest weed density and biomass and the highest weed control efficiency. Additionally, performing hand weeding twice (30 and 60 days after sowing) in conjunction with 180 kg N ha-1, followed by the application of Sulfosulfuron (25 g ha-1) + 2, 4-D (750 ml ha-1), significantly reduced Anagallis arvensis, Chenopodium album and Vicia sativa population and biomass and improved weed control effectiveness. Higher weed dry weight and population results in lower plant nutrient uptake and lower dry matter of crop plant and yield.

Weed smothering efficiency of mulching types on groundnut (Arachis hypogea L.) productivity in the dry savanna region of Nigeria

In order to increase groundnut productivity, a field experiment was carried out in the dry season of 2020 to assess the effectiveness of various mulching materials at suppressing weeds. The experimental treatments comprised of five mulching types; Control (no mulch), transparent polythene mulch, black polythene mulch, rice straw mulch and saw dust mulch) and three groundnut varieties (SAMNUT 23, SAMNUT 24 and SAMNUT 26). These were factorially combined and laid out in a Randomized complete block design with three replications. Findings revealed that mulching had a significant (p < 0.05) impact on crop qualities including canopy cover, chlorophyll content, pod yield, 100 kernel weight, and groundnut kernel yield as well as weed attributes like weed cover scores, weed density, weed dry weight, and weed control efficiency in both BUK and Wasai, respectively. The weed compositions were further grouped into various families comprising Poaceae (11), Euphorbiaceae (3), Amaranthaceae (4), Asteraceae (3), Cyperaceae (2), Cucurbitaceae, and Aizoaceae, each having one species with a different level of occurrence across the two locations. On the other hand, SAMNUT 26 significantly produced higher pod (2798 & 2119) and kernel yields (1198 & 1191), although SAMNUT 23 produced a heavier 100 kernel weight (55.51 & 54.52) at BUK and Wasai, respectively. In comparison to the other mulching types, applying black polythene mulch or transparent mulch lowered weed density and dry weight by limiting the amount of sunlight that the weeds got, preventing them from growing. Therefore, for dry season production of groundnut in the Sudan savannah ecology of Nigeria, mulching with black or transparent polythene film using the SAMNUT 26 variety was found to be effective in conserving soil moisture for optimum crop growth and development, while on the other hand, weed populations were suppressed.

Effect of Pre- and Post-Emergence Herbicides on Weed Control and Yield in Sunflower (Helianthus annuus L.)

Weeds are a major cause of yield and quality loss in sunflower (Helianthus annuus L.) crops. Therefore, weed control is important in sunflower production. In this context, the study was conducted in 2023 to determine the effectiveness of pre-emergence and post-emergence herbicides with different modes of action on weed population, dry weight of weeds and sunflower yield and yield components in sunflower. Four herbicides with different modes of action, three pre-emergence (aclonifen (A), pendimethalin (P), linuron (L) and one post-emergence (quizalofop-p-ethyl) (Q) and combinations of these herbicides were used in the study. To determine the effects of herbicides on weed populations and species, four different assessments were conducted at regular intervals. As a result of the study, a total of 10 weed species belonging to 5 families were detected in the trial area. The weed species with the highest density were Sorghum halepense (L.) Pers., Xanthium strumarium L., Convolvulus arvensis L. and Chenopodium album L. The study found that the effects of herbicides on weed populations and species varied. In the study, the highest rates of weed control were achieved in plots where both pre-emergence and post-emergence herbicides were used together. The highest weed control rate was observed in plots P+Q (96.66%). The highest effect on weed dry weight was obtained in plot L+Q with a rate of 89.63%. The highest weed dry weight was recorded in the weedy control plots. In the study, the highest yield (287.53 kg da-1) was obtained in the weed-free (hoe) control plot. Yield increases of 18% to 45% can be achieved by controlling weeds in sunflowers. As a result, herbicide efficacy on weed population and dry weight of weeds increased when herbicides were used in combination. Some herbicides have been shown to increase yields when used alone. However, it is important to use herbicides in combination to control more weed populations and prevent a potential resistance problem.

Assessing Herbicide-Resistance and Yield Optimization in Boro Rice (cv. BRRI dhan29) through Post-emergence Herbicides Applications

Effective weed management is crucial for achieving optimal crop performance and yield in rice cultivation. While post-emergence herbicides are commonly used to control weed population (WP), their effectiveness can vary based on the dosage and combinations applied. In this respect, an experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh, from December 2019 to May 2020 to predict herbicide-resistant weeds and assess the yield of boro (dry season irrigated) rice (cv. BRRI dhan29) in response to post-emergence herbicides. The experiment consisted of five post-emergence herbicides: Fenoxaprop-p-ethyl, Triafamone, Penoxsulam, Bispyribac-sodium, and Carfentrazone-ethyl, and four doses of herbicide: control, half of the recommended dose (RD), RD, and double the RD. Weed dry weight (DW), WP, and inhibition were significantly affected by different doses of herbicides. Ten weed species (WS) belonging to four families infested the experimental plots, with the most dominant being Echinochloa crus-galli, Scirpus mucronatus, and Scirpus articulatus. The lowest WP and DW, as well as the highest weed control efficiency (WCE), were achieved with double the RD of Penoxsulam and Triafamone, showing 91.09% and 90.13% efficiency, respectively, at 30 DAT. The tallest plants, highest number of effective tillers hill-1, highest grain yield, straw yield, biological yield, and harvest index were found with double the RD of Penoxsulam. In contrast double the RD of Triafamone produced the second-highest grain yield. Although double doses of herbicides increased yield, the variation was not significantly greater than the RD. Some weeds, particularly E. crus-galli, S. articulatus, Leersia hexandra, and Digitaria sanguinalis, survived even with double the RD of herbicides. This indicates a potential for herbicide-resistant weeds.

Productivity and Profitability of Indian Mustard as affected by Integrated Weed Management

Background: Weed infestation is a primary cause of reduced yields, with estimated losses ranging from 10-70% due to crop-weed competition in Indian mustard. Therefore, it is essential to implement effective weed control measures to optimize the crop¢s yield potential. A combination of herbicides with manual, culturaland mechanical approaches is desirable to achieve optimal weed control. Therefore, a field experiment was carried out to evaluate the effect of integrated weed management on the productivity and profitability of Indian mustard. Methods: The experiment was conducted at the Agronomy Main Research Farm, College of Agriculture, Orissa University of Agriculture and Technology (OUAT), Bhubaneswar during rabi season of 2021-22 and 2022-23. It consisted of eight treatments in a randomized block design (RBD) with three replications. Result: Pendimethalin 0.75 kg ha-1 fb straw mulch 5 t ha-1 controlled the mixed flora of weeds which resulted in the lowest weed density, weed dry weight, weed index and highest weed control efficiency which resulted in the highest grain yield and stover yield of mustard. Pre-emergence application of pendimethalin 0.75 kg ha-1 fb straw mulch 5 t ha-1 registered the highest benefit-cost ratio.

Compatibility Analysis of Metolachlor and Pendimethalin for Weed Control in Arabica Coffee Plants

Losses caused by the presence of weeds in an agricultural business are often associated with the ability of weeds as strong competitors for plants to obtain water, nutrients, sunlight, and growing space. A mixture of metolachlor and pendimethalin herbicides is expected to control important weeds of various classes in coffee plants. The purpose of the research was to determine the effect of two herbicide mixtures at different doses on weeds in coffee plantations. This research used a 4 X 4 factorial randomized block design with 2 repetitions, resulting in 32 experimental plots. The first factor was metolachlor herbicide and the second was pendimethalin herbicide, each factor consisting of 4 levels with 0.00, 0.75, 1.75 and 2.25 kg ha-1 doses. The observed parameters consisted of (1) dominance count value, (2) percentage of controlled weeds, (3) weed coverage, (4) weed population, and (5) weed dry weight. The results showed that there was a very significant effect on the combined interaction of metolachlor and pendimethalin herbicide mixtures on the percentage of controlled weeds, percentage of weed closure at 21 and 28 DAA, and weed dry weight at 28 and 42 DAA with the best dose combination at b.a. 1.50 kg ha-1 which could increase the efficiency of weed control. Meanwhile, the percentage of controlled weeds, percentage of weed cover at 14 DAA, and weed population at 28 and 42 DAA showed very significant results independently with a dose of b.a. 2.25 kg ha-1

Determining Critical Weed Competition at Different Weed Free Periods in Linseed in Holeta District Central Ethiopia

A substantial proportion of linseed yield is lost due to weeds in the Holeta area of Central Ethiopia. The weeds infest the crop fields during the early growth stage and consume growth resources. To protect the crops from weeds, farmers manage their fields using cultural practices. However, there is a knowledge gap between farmers on critical weed removal time for the management of the weeds from the crop. Therefore, it is assumed that determining the weed-free period after the sowing of linseed to control the weeds is necessary. The experiment was designed to determine the suitable weed-free period for the control of weeds and increasing linseed production. The trial was treated with different weed-free periods before 20, 30, 40, 50, and 60 days of sowing; and after 20, 30, 40, 40, and 60 days of sowing, twice hand weeding, weed-free, and control. The treatments were organized in a Randomized Complete Block Design (RCBD) replicated three times. It was found that Galinsogapulviflora was the most dominant weed, contributing to 18% of the total weeds present in the fields. Plots treated with weed-free after 20 days of sowing produced superior results in terms of reduction of weed dry weight by 100%, increased number of bolls per plant by 3.08 folds, stand count by 245%, and grain yield by 11 folds as compared to untreated check respectively. Hence, making weed free of linseed after 20 days of sowing is recommended for the management of various weeds in linseed.

Efficacy of 2, 4-D Sodium Salt 80% WP on Weeds, Productivity and Economics of rabi Maize (Zea mays L.)

Rabi maize is affected by three types of weed species mainly broad-leaf weeds in eastern pockets of Uttar Pradesh and causes grain and stover yields loss in higher amount. Therefore present study was carried out to find the most effective dose of 2, 4-D Sodium salt 80% WP on killing of braod-leaf weeds. A field investigation was conducted during Rabi season of (2021) at Varanasi, Uttar Pradesh, to study the efficacy of 2, 4-D Sodium salt 80% WP on weeds, productivity and economics of rabi maize (Zea mays L.). 2, 4-D Sodium salt 80% WP 1250 g/ha at 25 DAS recorded lesser weed density and weed dry weight of Physalis minima, Chenopodium album, Parthenium hysterophorus and Cichorium intybus at 45 DAS as compared to other doses of 2, 4-D. Number of cobs, number of grains, number of grains/ row, seed index in comparison were superior in 2, 4-D Sodium salt 80% WP 1250 g/ha at 25 DAS with improved grain and stover yields and higher monetary returns during the study.

Effect of the Integrated Weed Control Practices on Sugar Beet Yield, Quality and Associated Weeds

Two-years field trial (2017/18 and 2018/19) was conducted at the Experimental Farm, National Research Centre El-Behaira Governorate, Egypt to compare different herbicidal combinations with different doses on sugar beet yield traits and associated weeds. Sixteen weed control treatment combinations were applied to test their efficiency on sugar beet yield and quality. To form these combinations two broadleaves herbicides (Tigro and Betasana-Trio) were combined with a narrow weed herbicide (Select super) or with the hand weeding treatment. The results showed that Betasana-Trio combination at the lower dose of application 0.675 l fed-1(fed-1 = feddan = 4200 m2) combined with Select Super at 0.375 l fed-1 with or without hand weeding as well as Betasana-Trio at 0.9 l fed-1 combined with hand weeding or Select Super at 0.5 l fed-1 caused high eradication percentages of the total fresh and dry weight of weeds as well as total number of weeds m-2 (>90%). The highest sugar beet yield resulted from the combination of Betasana-Trio 0.675 l fed-1 + Select Super 0.375 l fed-1, which gave the greatest sugar yield fed-1. Although the combination Betasana-Trio at 0.9 l fed-1 + Select Super at 0.5 l fed-1 gave the greatest gross sugar %, it could not achieve the highest sugar yield fed-1.

Efficacy of Sequential Applications of Pendimethalin 500 EC (Pendimight®) and Oxyfluofen 240 EC (Harris®) for Weed Control in Direct Seeded Onion (Allium cepa L.) in Sudan

A field study was carried out to evaluate the efficacy of pendimethalin 500 EC (trade name: Pendimight®) and oxyfluorfen 240 EC (trade name: Harris®) to control weeds in direct-seeded onion (Allium cepa L.). Pendimethalin and oxyfluorfen were applied solely at reduced rates (1.35 and 0.17 kg a.i. ha-1), and at the recommended rates (1.8 and 0.25 kg a.i. ha-1) as pre-and post-emergence herbicides, respectively. Both herbicides were also applied sequentially at the same doses. Ten weeks after sowing (WAS), the application of pendimethalin alone provided better weed control (62% - 65%) than oxyfluorfen alone (33% - 43%) when they were applied at the lower and recommended rates, respectively. Sequential applications of the two herbicides as pre-and post-emergence herbicides, outperformed applications of the two herbicides alone, and resulted in the best weed control (79% to 85%), lowest weed dry weight (18.35 to 35.60 g.m-2), significantly increased plant height and the number of leaves per plant, and resulted in a ten-fold higher onion yield (24.64 to 26.37 t. ha-1) compared with the Un-weeded control (2.27 t. ha-1). There were no significant differences observed between the treatments on the emergence (%) of onion seeds and the survival of onion seedlings. Sequential applications of pendimethalin and oxyfluorfen is a promising techniques for weed control in direct-seeded onions in Sudan.

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.

Evaluating the effects of manual hoeing and selective herbicides on maize (Zea mays L.) productivity and profitability

The objective of this study was to evaluate maize production and the economic profitability of weed management techniques. Field trials were conducted at the Kasapa farm during the 2021/22 growing seasons using a split-plot design with three repetitions. The main factor was the herbicides applied in pre-emergence alone (2L ha−1: acetochlor, bentazon, imazethapyr and 60 g ha−1 chlorimuron-ethyl), then mixed (1L ha−1: acetochlor plus bentazon plus imazethapyr plus 30g ha−1chlorimuron-ethyl), manual hoeing (3-5WAS) including the non-weeding. The secondary factor: maize varieties (GV672A, GV673A, GV664A and Sam4vita). The highest maize dry grain yield (7.66 t ha−1) was associated with imazethapyr, while those of acetochlor and chlorimuron-ethyl (6.86 and 6.92 t ha−1) compared to manual hoeing (7.62 t ha−1, respectively) were low, but much higher than no weeding (1.21 t ha−1). The yields of varieties GV672A and GV664A were higher (6.87 and 6.77 t ha−1), compared to Sam4vita (5.64 t ha−1). The total dry weight of weeds was negatively correlated with all crop parameters, with its maximum value (127.56 g m−2) characterizing non-weeding, and the minimum for manual hoeing (18.83 g m−2). The Ratio Cost Value showed that all treatments were profitable: imazethapyr > bentazon > chlorimuron-ethyl > combination > acetochlor > manual hoeing. However, imazethapyr was economically more profitable and could replace manual hoeing when the field to be weeded increases and labor is scarce.

Determining the Effect of Nutrient Management and Weed Control Practices on Weed Dynamics in Wheat (Triticum aestivum L.)

An experiment was carried out at Agronomy Research Farm of Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (Uttar Pradesh) during Rabi season (2022-23 & 2023-24) to investigate the effect of nutrient management and weed control practices on dynamics of weed in different treatments in wheat crop. Split plot design was used in the experimental field with three nutrient levels in main plot and six weed control practices in sup plot and replicated thrice. Among the nutrient management treatments 75% RDF + 10 t ha-1 FYM + one spray of nano-urea @ 4ml/lit was found to be more effective for controlling weed density, weed dry weight, weed control efficiency (%), and weed index (%) during both years of experimentation. Sequential spray of Clodinofop + Metsulfuron (60 + 4 g a.i. ha-1) reduced the density and dry weight of weeds, however recorded highest weed control efficiency (89.57% & 90.77%) and minimum weed index (1.99 & 1.96) during 2022-23 and 2023-24 respectively. The better control of weeds and higher uptake of nutrient in this treatment resulted in higher yield. Thus it might be concluded that application of 75% RDF +10 t ha-1 FYM + one spray of nano-urea @ 4ml/lit with the spraying of Clodinofop + Metsulfuron (60 + 4 g a.i. ha-1) found to be more effective in reducing weed infestation in wheat crop.

Optimizing Agronomic Practices for Aerobic Rice under Calcareous Soil in Bihar

Three experiments were conducted during 2014-19 at Pusa (Samastipur), Bihar, to develop agronomic practices for aerobic rice with respect to the performance of varieties at different dates of sowing, optimizing seed rate and spacing, and nitrogen requirement and its scheduling under the calcareous soil of North Bihar plains. Sowing during the first week of June resulted in significantly higher yield attributes and grain yield. Among varieties, Abhishek recorded significantly higher grain yield except for the hybrid. Weather variables during different growth phases significantly influenced the yield. The hybrid outyielded all the test varieties. Maximum grain and straw yields were recorded with 20 cm spacing and a 35 kg/ha seed rate. Also, the minimum dry weight of weeds was recorded with this spacing and seed rate. Nitrogen at 140 kg/ha in three or four splits along with brown manuring resulted in significantly higher grain and straw yields. Also, the maximum uptake of NPK and B:C ratio was recorded with this treatment.