Background: Chickpea (Cicer arietinum L.) is the most important pulse crop widely cultivated for its nutritional and economic value. However, weed infestation poses a significant challenge to chickpea production, leading to reduced growth and productivity. Effective weed management strategies are therefore essential to mitigate the losses due to weeds and improve crop productivity. Selective herbicides with low or no phytotoxicity to the crop offer a promising solution for controlling weeds in order to boost up crop productivity. Currently available post emergence herbicides such as imazethapyr, can cause phytotoxic effects on chickpea. Therefore, it is essential to identify new post-emergence herbicides that can effectively control weeds without harming plant health. This study investigates the impact of topramezone, a selective post-emergence herbicide, on weeds as well as growth and productivity of chickpea. 
 
Methods: A field experiment was conducted at Agricultural Farm of Palli Siksha Bhavana, Visva-Bharati, Sriniketan during rabi season of 2021-22 and 2022-23. The experiment was laid out in randomized block design with nine treatments and three replications. The treatments were - T1 - topramezone 15 g ha-1 as POE, T2 - topramezone 17.5 g ha-1 as POE, T3 - topramezone 20 g ha-1 as POE, T4 - topramezone 22.5 g ha-1 as POE, T5 - topramezone 25 g ha-1 as POE, T6 - imazethapyr 60 g ha-1 as POE, T7 - pendimethalin 750 g ha-1 as PE, T8 - weed free and T9 - unweeded control. The study assessed the density and dry weight of weeds, weed control efficiency, growth and yield parameters as well as yield of chickpea under various application doses of topramezone in comparison with imazethapyr and pendimethalin. 
 
Result: Among all the herbicides, post-emergence application of topramezone 25 g ha-1 at 25 days after sowing resulted the lowest density and dry weight of weeds, the highest growth (plant height, LAI) and yield parameters (number of pods plant-1, number of seeds pod-1), seed yield and harvest index. Therefore, post-emergence application of topramezone 25 g ha-1 at 25 days after sowing proved to be an effective herbicide for weed control in chickpea in the lateritic belt of West Bengal.

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Growth and Productivity Improvement of Chickpea (Cicer arietinum L.) through Weed Management by Topramezone

Background: A field experiment was conducted in the Agronomy Research Farm of the School of Agricultural Sciences (SAS), Nagaland University, Medziphema Campus, India during the Kharif season, 2023 and 2024 to study the weed dynamics and growth and yield of maize as influenced by tembotrione herbicide. 
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Methods: The experiment was laid out in randomized block design with three replications consisting of 10 treatments. The treatments include viz., T1: Weedy check, T2: Hand weeding at 20 and 40 DAS, T3: Tembotrione 100 g ha-1&nbsp;at 15 DAS, T4: Tembotrione 125 g ha-1&nbsp;at 15 DAS, T5: Tembotrione 150 g ha-1&nbsp;at 15 DAS, T6: Tembotrione 100 g ha-1&nbsp;at 30 DAS, T7: Tembotrione 125 g ha-1&nbsp;at 30 DAS, T8: Tembotrione 150 g ha-1&nbsp;at 30 DAS,T9: Atrazine 750 g ha-1&nbsp;at 2 DAS and T10: 2,4-D Na 800 g ha-1&nbsp;at 20 DAS. Surfactant Tween 20 (polyoxyethylene 20 sorbitan monolaurate or polysorbate 20) was used at the rate of 5 ml/litre of water. 
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Result: The results revealed that hand weeding twice at 20 and 40 DAS resulted in lowest population and biomass of grasses, sedges and broad leaf weeds and among the herbicides application Tembotrione 150 g ha-1&nbsp;at 30 DAS resulted in the lowest values which also resulted in highest weed control efficiency and lowest weed index. The plant height, dry matter accumulation and other yield attributing parameters also showed highest value in application of Tembotrione 150 g ha-1&nbsp;at 30 DAS under herbicides treatments resulting in higher yield. The gross and net return was observed highest in hand weeding treatments. However, with respect to profit, application of Tembotrione 150 g ha-1&nbsp;at 30 DAS resulted in highest benefit cost ratio which indicates beneficial use of this herbicide at 30 DAS.

Weed Dynamics and Growth and Yield of Maize (Zea mays L.) as Influenced by Tembotrione Herbicide

<div style="text-align: justify;">A field experiment was conducted to study the effect of pre-emergence, post emergence and combination of atrazine with post emergence herbicides on soil enzyme urease activity(expressed as &micro;g of NH4+ released g-1 soil h-1) at College Farm, College of Agriculture ,Professor Jayashankar Telangana State Agricultural University (PJTSAU), Rajendranagar, Hyderabad, India during kharif 2014. The experiment was laid out in randomized block design (RBD) using six herbicide treatments un weeded control and hand weeding at 20 and 40 DAS with three replications. Maize was sown as test crop(variety &ndash;DHM-117).The soil samples were collected at 15 days intervals ie: 0, 15,30,45, 60, 75 and 90 days, to assay the enzyme activity. The pre-emergence herbicides were sprayed at zero days after sowing where post- emergence herbicides were sprayed after 15 days after sowing. The enzyme activity in the control increased from 0 days to 60 days and then decreased but the activity in the pre- emergence herbicide pendimethalin showed the same phase as that of control and showed higher activity over the control at each stage where as atrazine showed decrease in activity at 0 days (8.71) and latter it revoked the activity and reached maximum at 60 days (12.35). When compare to pendimethalin the activity was less at each and every stage. In case of post &ndash; emergence herbicides the activity showed mixed responses to at different stages Tembotrione showed higher activity when compare to Topramezone. In combination of Tembotrione and Topramezone with atrazine showed mixed responses.</div>

<div style="text-align: justify;">Effect of herbicides on the activity of soil enzymes urease in maize crop</div>

<div>Background: Maize (Zea mays L.) is the most versatile and emerging food crop of global importance. Weeds are ubiquitous but their presence in wide spaced and initially slow growing crop like maize acts as an obstacle for plentiful harvest. Nutrient uptake by weeds during the first thirty days of maize growth was 59 kg N, 10 kg P2O5 and 59 kg K2O per ha, which was 7-10 times higher than the nutrient uptake by maize. 
 
Methods: The present field experiment was conducted during Rabi, 2018-19 under irrigated conditions at wetland farm of S.V. Agricultural College, Tirupati andhra Pradesh, with ten treatments and three replications in a randomized block design. 
 
Result: Lower density and dry weight of weeds with higher weed control efficiency, lower nutrient uptake by weeds and higher nutrient up take by maize at 80 DAS, kernel and stover yield was recorded with hand weeding twice at 15 and 30 DAS, which was statistically at par with atrazine 1.0 kg ha-1 as PE fb topramezone 30 g ha-1 or tembotrione 120 g ha-1 as PoE or atrazine 1.0 kg ha-1 as PE fb HW at 30 DAS, while these were lowest with weedy check. Higher benefit cost ratio of maize was noticed with both atrazine 1.0 kg ha-1 as PE fb topramezone 30 g ha-1 as PoE (T3), which was in parity with atrazine 1.0 kg ha-1 as PE fb tembotrione 120 g ha-1 as PoE (T2) and hand weeding twice at 15 and 30 DAS (T9). From the present study it may be concluded that atrazine 1.0 kg ha-1 as PE fb topramezone 30 g ha-1 or tembotrione 120 g ha-1 as PoE were considered to be the most effective and economic weed management practices to increase the productivity of Rabi maize at times of labour scarcity.</div>

<div>Weed Dynamics and Nutrient Uptake of Maize as Influenced by Different Weed Management Practices</div>

<div>Background: Maize popularly known as &ldquo;Queen of cereals&rdquo;. Weeds resulted in the highest crop loss (33%), followed by pathogens (26%), insects (20%), storage pests (7%), rodents (6%) and others (8%) in India. Application of herbicides will affect various soil microbial processes and enzymatic activities in the soil, whose activity is very important for maintaining the soil fertility. 
 
Methods: The present field experiment was conducted during Rabi, 2017-18 and 2018-19 under irrigated conditions at wetland farm of S.V. Agricultural College, Tirupati Andhra Pradesh, with ten treatments and three replications in a randomized block design.&nbsp; 
 
Result: Higher kernel and stover yield of maize was recorded with hand weeding twice at 15 and 30 DAS and the yield loss was comparatively lower with atrazine 1.0 kg ha-1as PE fb topramezone 30 g ha-1or tembotrione 120 g ha-1 as PoE or atrazine 1.0 kg ha-1as PE fb HW at 30 DAS, while these were lowest with weedy check. Soil microbial count and enzyme activity was statistically comparable in all the pre followed by post emergence herbicide treatments.&nbsp;</div>

Response of Weed Management Practices on Yield Loss, Soil Enzyme Activity and Microbial Populations in Maize (Zea mays L.)

<div>Background: Maize followed by summer pulses is the emerging cropping system in many places in India. Herbicides are the efficient tools for checking weed infestation and their usage is increasing throughout the globe due to increased labour cost and quick weed control. Some herbicides do not degrade quickly and may remain in the soil for weeks, months or years after application and may inhibit the growth of succeeding crops.&nbsp; 
 
Methods: Field experiment was conducted in a randomized block design (RBD) during rabi and summer seasons of 2017-18 and 2018-19 to know the residual effect of different herbicides applied in maize on succeeding greengram.&nbsp; 
 
Result: The present study revealed that lower density and dry weight of total weeds and higher yield attributes and yield was recorded with the practice of adopting two hand weedings at 15 and 30 DAS, which was however, at par with atrazine 1.0 kg ha-1 as PE fb one HW at 30 DAS, atrazine 1.0 kg ha-1 as PE fb topramezone 30 g ha-1 as PoE and atrazine 1.0 kg ha-1 as PE fb tembotrione 120 g ha-1 as PoE, without any significant disparity among them. Herbicides applied in maize did not alter statistically the enzyme activity and microbial count in the soil at harvest of succeeding greeengram.&nbsp;</div>

<div>Residual Effect of Weed Management Practices Executed in Preceding Maize on Succeeding Greengram</div>

Background: Cereal-legume cropping system is considered to be one of the better alternatives for sustaining soil fertility and increasing the yield. At present maize-groundnut cropping system is gaining importance under both rainfed and irrigated situations. Maize, being an exhaustive and weed-sensitive crop, is supplied with large doses of fertilizers and new herbicide molecules.Since maize is exhaustive and weed sensitive crop, there was a usage of excessive fertilizers and new herbicides. There is a need to assess the carry over effect of fertilizers and new generation herbicides in leguminous crops like groundnut. 
 
Methods: The experiment was conducted during two consecutive rabi seasons of 2019-20 and 2020-21 on sandy loam soils of S.V. Agricultural College, Tirupati, Andhra Pradesh. Maize hybrid DHM -117 was sown and maintained with general cultivation practices except for nitrogen and weed management methods was raised after harvest of maize in undisturbed layout to study the residual effect of different nitrogen and weed management practices imposed in maize. 
 
Result: Residual effect of nitrogen and weed management practices imposed in preceding maize did not exert any significant influence on germination percentage, phytotoxicity and SPAD chlorophyll meter reading (SCMR) values but efficacy of herbicide residue found to be significant with weed management practices. Growth parameters, yield attributes pod yield, haulm yield and economics were higher in groundnut with brown manuring, which was however, in parity with hand weeding twice at 15 and 30 DAS, pre emergence application of atrazine 1.0 kg ha-1 fb post emergence application of topramezone 30 g ha-1 and pre emergence application of atrazine 1.0 kg ha-1 fb post emergence application of tembotrione 120 g ha-1 and lower with unweeded check and it was remained in parity with application of parthenium water extract15 lha-1 twice at 15 and 30 DAS, application of sunflower water extract 15 lha-1 twice at 15 and 30 DAS, pre emergence application of atrazine 1.0 kg ha-1 fb post emergence application of parthenium water extract 15 lha-1 and pre emergence application of atrazine 1.0 kg ha-1 fb post emergence application of sunflower water extract 15 lha-1 in the order of ascent.&nbsp; None of their interaction effects were found to be significant during both the years of study and in pooled mean.

Residual Effect of Nitrogen and Weed Management Practices in Maize on Succeeding Groundnut

Background: Maize, being highly productive and versatile cereal crop, is influenced by various biotic and abiotic stresses. Among biotic stresses, weed infestation is one of the serious concerns in maize cultivation. Weeds can affect maize by competing for light, water and nutrients resulting in yield loss of up to 70% in severe cases.&nbsp; 
 
Methods: A field experiment was conducted during kharif season for two consecutive years of 2019 and 2020 in agriculture farm of Palli Siksha Bhavana (Institute of Agriculture), Visva-Bharati, Sriniketan, West Bengal, India.&nbsp; The experiment was laid out in randomized block design and replicated thrice. The experiment comprised of seven weed management treatments viz. T1 (tembotrione 9% + atrazine 45% WG @ 1000 g/ha), T2 (tembotrione 9% + atrazine 45% WG @ 1250 g/ha), T3 (tembotrione 9% + atrazine 45% WG @ 1500 g/ha), T4 (Tembotrione 34.4% SC @ 286 ml/ha), T5 (Atrazine 50% WP), T6 (Hand weeding), T7 (Weedy check).&nbsp; 
 
Result: Experimental results revealed that among different herbicide mixtures, tembotrione + atrazine 1500 g/ha was found to be effective in suppressing the weeds growth and found no residual effect on soil chemical and biological properties during both the years of the experiment.

Effect of Ready Mix Application of Herbicide on Weed Dynamics and Productivity of Maize in Lateritic Belt of West Bengal

<div>Background: Weeds are the most critical pest, which cause the highest yield reduction in food grain crops. Weeds interfere with maize growth by competing one or more growth limiting factors, controlling of weeds in maize during the critical period assumes great importance for realizing higher yield. Unavailability of relatively cheap labour in time necessitated the use of herbicides in maize. Residual impact of herbicides caused significant influence on germination and growth of succeeding crop. 
 
Methods: The field experiment was carried out during kharif 2019 at Agricultural College and Research Institute, Madurai to evaluate the residual effect of herbicides used in preceding maize on succeeding blackgram. Treatments were application of pre emergence herbicide atrazine at 0.25 kg ha-1 or pendimethalin 1 kg ha-1 applied singly on 3 days after sowing and in combination with post emergence herbicide tembotrione 120 g ha-1 or halosulfuron methyl 90 g ha-1 on 25 DAS, weed free check, unweeded check in maize crop. 
 
Result: Among the weed control treatments, pre emergence herbicides atrazine 0.25 kg ha-1 or pendimethalin 1 kg ha-1 singly and in combination with post emergence herbicides tembotrione 120 g ha-1 or halosulfuron methyl 90 g ha-1 applied in maize crop did not caused any phyotoxicity and residual impact on succeeding blackgram. However, the highest plant height (29.5 cm), dry matter production (1.17 g plant-1) and seedling vigour index (1473) of succeeding blackgram was recorded in atrazine at 0.25 kg ha-1 as pre emergence at 3 DAS followed by tembotrione at 120 g ha-1 as post emergence at 25 DAS.</div>

​​Preceding Maize Crop Herbicide Residual Effect on Germination, Growth and Vigour of Succeeding Blackgram

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.

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