<div>Background: Weeds are the major biotic constraint to reduce the rice productivity in direct wet seeded rice. Weed infestation and competition are severe in direct wet seeded rice as compared to transplanted rice, because of the simultaneous growth of both crops and weeds. The yield loss due to weeds varies from 40 to 100 per cent in direct seeded rice. Use of herbicides either singly or in combination with manual or mechanical weeding in puddled direct seeded rice has been highlighted by several workers. Use of alternative herbicides with wide spectrum control of the weeds in direct seeded puddled rice is the need of the present time. The present study aimed to evaluate different weed management practices in direct wet seeded rice under sodic soil. 
 
Methods: A field experiment was conducted during Samba season (Rabi) 2016-17. to evaluate the weed management practices in direct wet seeded rice under sodic soil. The treatments comprised of different combination of weed management practices viz., pre emergence, early post emergence herbicides, mechanical weeding and hand weeding twice were tested. Total weed density and weed dry weight, weed control efficiency, yield parameters and yield of rice were recorded.&nbsp; 
 
Result: Among the different weed management practices, the lowest total weed density, total weed dry weight and higher WCE, yield attributes, grain and straw yields were registered under application of PE pyrazosulfuron ethyl 25 g/ha fb EPOE bispyribac sodium 25 g/ha. This was followed by application of PE pretilachlor 0.75 kg/ha fb EPOE bispyribac sodium 25 g/ha.&nbsp;</div>

<div>Weed Dynamics and Productivity of Direct Wet Seeded Rice under Different Weed Management Practices</div>

<div>Background: Weeds are the major threat to direct seeded rice and a single strategy of weed control may not be effective for season-long weed control. Intending to accomplish the long-term and sustainable weed management of direct seeded rice, the integration approach of weed management strategies seems a better alternative. The current field study was aimed to evaluate the impact of integration of different weed control methods on direct seeded rice under irrigated ecosystem on weed growth and rice yield.</div>

<div> 
Methods: The experiment was laid out in randomized block design with three replications and twelve treatments during 2017 at G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India. The twelve treatments included the combination of cultural, mechanical, physical and chemical weed management methods.</div>

<div> 
Result: Combination of stale seedbed technique integrated with pre-emergence application of pendimethalin with mechanical weeding at 25 DAS followed by 1 hand weeding at 45 DAS, Sesbania (line sowing) fb application of pendimethalin (PE) fb 1 mechanical weeding at 25 DAS fb 1 hand weeding at 45 DAS, stale seedbed with application of pendimethalin (PE) with Sesbania brown manuring supplemented with mechanical weeding (25 DAS) fb hand weeding at 45 DAS, mulching with wheat straw mulch along with post-emergence application of penoxsulam (20 DAS) fb 1 hand weeding at 45 DAS and application of pendimethalin (PE) fb penoxsulum (PoE) at 20 DAS fb 1 hand weeding at 45 DAS with a row spacing of 25 cm found to be similar in the suppression of weed population and weed density at 40 and 60 DAS and crop yields (4.3, 4.1, 4.2, 4.0 and 4.2 t/ha, respectively) were on par with weed free plot i.e. 4.4t/ha. Application of pendimethalin (PE) fb penoxsulum (PoE) at 20 DAS fb 1 hand weeding at 45 DAS with row spacing of 25cm recorded 93.7%, 90.6% and 4.5% weed control efficiency, weed control index and weed index respectively, which was similar with above integrated weed management treatments. A negative correlation of the weed density and dry matter with the yield of rice was recorded.</div>

​Effect of Integrated Weed Management on Weed and Yield of Direct Seeded Rice

<div>Background: Balancing productivity, profitability and environmental health is a key challenge for maintaining agricultural sustainability. The use of locally available agro-inputs in agriculture by avoiding or minimizing the use of synthetically compounded agro-chemicals appears to be one of the probable options to sustain the agricultural productivity. Widespread use of herbicides has resulted in purported environmental and health problems as well as residual toxicity issues in succeeding crops. At present, the awareness on safe food is increasing. So, keeping this point in view the present investigation was carried out to evaluate the influence of organic sources of nutrients and weed management on growth, yield and weed flora of Frenchbean.&nbsp; 
 
Methods:&nbsp;A field experiment was conducted during summer season of 2016 and 2017. The present investigation was laid out in split plot design with six sources of nutrients in main plot and four weed management treatments in sub plots.&nbsp; 
 
Result: Application of treatment T5 recorded significantly higher growth parameters, yield attributes, fresh pod yield, net returns and B:C ratio of French bean which was statistically at par with T3 and T2. Amongst the weed management treatments, treatment W1 resulted in significantly lowest species wise and total weed density and biomass, highest weed control efficiency, lowest weed index, highest growth, yield attributes and fresh pod yield of French bean which was statistically at par with W2 and W0. However, the highest net returns and B:C ratio were obtained in weed free plots.</div>

Weed Dynamics and Productivity of French Bean (Phaseolus vulgaris L.) as Influenced by Organic Sources of Nutrients and Weed Management

A field experiment was conducted at Forage Research and Management Centre, NDRI, Karnal during rabi season in 2013-14 to study the effect of nitrogen application and weed management on growth and yield of fodder turnip (Brassica compestris var. rapa) with four levels of nitrogen (0, 50, 100, and 150 kg N/ha) and four weed management practices (pendimethalin @ 1.0 kg a.i./ha, hand weeding, isoproturon @ 0.75 kg a.i./ha and weedy check) in split plot design. Among the nitrogen treatments 150 kg nitrogen/ha gave the highest growth, yield and better quality of fodder turnip. Application of &nbsp;pendimethalin @1.0 kg a.i. proved better in terms of &nbsp;growth and yield of turnip. Weed control efficiency was 65% with &nbsp;150 kg N/ha and 83.23% with pendimethalin 1.0 kg a.i./ha.

Effect of nitrogen and weed management on weed control efficiency and&nbsp;yield of fodder turnip

<div>The present study was conducted in kharif seasons of 2015, 2016 and 2017 at experimental farm of Rajasthan Agricultural Research Institute, Durgapura, Jaipur (Rajasthan) to study efficacy of different weed management practices in clusterbean. Three years result shows that compared to weedy check (6.82 m-2) application of Pendimethalin @ 0.75 kg a.i. ha-1 as PE fb one hand weeding recorded lowest weed density (3.58 m-2). Among herbicidal treatments, Pendimethalin @ 0.75kg a.i/ha as PE fb one hand weeding at 25 DAS (83.7%) and Pendimethalin @ 0.75 kg a.i./ha as PE+ Imazathapyr+ Imazamox @ 40g a.i./ha PoE (74.0%) recorded highest weed control efficiency. Likewise, application of Pendimethalin @ 0.75kg a.i/ha as PE fb one hand weeding at 25 DAS and Pendimethalin 0.75kg/ha at PE fb Imazathapyr + Imazamox @ 40g a.i. ha-1 recorded significantly higher seed (1136 kg ha-1 and 1009 kg ha-1), haulm (3304 kg ha-1 and 2943 kg ha-1) and biological yield (4440 kg ha-1 and 3953 kg ha-1), respectively over other herbicidal treatments. Economic evaluation indicated that application of Pendimethalin @ 0.75kg a.i/ha as PE fb one hand weeding at 25 and which was followed by with Pendimethalin @ 0.75 kg a.i./ha as PE+ Imazathapyr+ Imazamox@ 40g a.i./ha recorded, gross return (INR 55352 ha-1 and INR 49189 ha-1) net returns (INR 38852 ha-1 and INR 34289 ha-1) and B:C ratio (2.35 and 2.20), respectively. Whereas, minimum cost of cultivation (INR 10000 ha-1) and gross returns (INR 25632 ha-1), net returns (INR 15632 ha-1) and B:C ratio (1.56) were recorded under weed check. So looking to the laborious pressure of hand weeding, cost effectiveness ease of application of chemical herbicides, application of Pendimethalin 0.75 kg ha-1 fb one hand weeding can be an effective weed control option in cluster bean crop with higher seed and haulm yield under Semi-arid and Arid regions of Rajasthan.</div>

<div>Effect of Different Weed Management Practices on Weed Dynamics, Productivity and Farm Profitability of Cluster Bean</div>

<div style="text-align: justify;">Field investigations were conducted during 2015 and 2016 kharif seasons at the experimental farm of ICAR, Nagaland Centre, Medziphema to study weed growth and nutrient uptake in organically managed rice and maize as affected by N management and live mulching with cowpea. The experiment was laid out in factorial RBD with two kharif crops viz., rice (C1) and maize (C2), two organic N management viz., vermicompost @ 2 t/ha (N1) and vermicompost @ 2.7 t/ha (N2) and two mulches viz., control (No mulching) (L1) and live mulching with cowpea (L2). The dominant weed species observed were Cynodon dactylon, Digitaria setigera, Ageratum conyzoides, Amaranthus viridis, Cyperus iria and Cyperus rotundus. Weed density, dry weight and NPK uptake was found to be significantly lower in maize compared to rice during both years. Weed growth and NPK uptake was also found to be significantly higher with application of vermicompost @ 2.7 t/ha (N2) compared to 2 t/ha (N1) whereas, significantly lower weed growth as well as NPK uptake was also recorded with cowpea live mulch (L2) as compared to no mulching (L1). Cowpea live mulch (L2) with application of vermicompost @ 2 t/ha (N1) was found to record significantly lower NPK uptake by weeds in both crops. Yield and yield attributes of rice and maize were observed to be higher under cowpea live mulch with application of vermicompost @ 2.7 t/ha (N2).</div>

Weed growth and nutrient uptake in organically managed rice and maize as affected by nitrogen management and live mulching with cowpea

<div>Background: To study effect of various spacing and weed management practices on weed control, growth parameter, yield and yield attributes of pigeon pea variety Pusa Arhar-16, field experiments were conducted at Student&rsquo;s Research Farm, Khalsa College Amritsar, Punjab, India during kharif season of 2019-20. 
 
Methods: The experiment was laid out in Split plot design with three replications. The treatments comprised of four different spacing i.e. S1 (30&times;10 cm), S2 (30&times;15 cm), S3 (40&times;15 cm) and S4 (50&times;25 cm) which were considered as main plot treatments and three weed management practices W1 (weedy check), W2 (pendimethalin @ 1.5 kg a.i. ha-1 at 1DAS) and W3 (rice straw mulch) as sub-plot treatments. 
 
Result: It was found that maximum plant height (218.2 cm) and highest leaf area index (2.104) was recorded in treatment S1 (30&times;10 cm) whereas treatment S4 (50&times;25 cm) was superior in rest of growth parameters viz. maximum crop growth rate (0.85 gram per plant per day), number of primary branches (18.2 per plant) and number of secondary branches (13.8 per plant). Among yield and yield attributes, spacing S1 (30&times;10 cm) showed maximum grain yield (16.29 q ha-1) and stover yield (49.29 q ha-1) whereas, maximum number of pods per plant (154.6), pod length (4.83 cm), number of seeds per pod (3.90) and 100-seed weight (7.14 grams) were recorded in spacing S4 (50&times;25 cm). The weed management treatments showed non-significant effect on growth and yield parameters due to weed suppressing ability of the crop. which might be due to weed suppressing ability of the crop. It may be concluded that pigeon pea cultivar Pusa Arhar-16 performed better in narrower spacing of 30&times;10 cm due to its dwarf nature and it also showed good smothering effect on the weeds due to its smothering effect.</div>

<div>Effect of Different Spacing and Weed Management Practices on Weeds, Crop Growth and Productivity of Pigeon Pea Variety Pusa Arhar-16</div>

Background: Weeds are one of the most important elements influencing crop productivity. Tillage practices have a significant effect on the weed seed bank and the appearance of weeds, both of which have a direct impact on farm productivity. Different tillage strategies based on ploughing depth, as well as weed control practices, change the dynamics of weed seeds in the soil. This research will aid in the development of integrated weed control methods by investigating the interaction between tillage and weed management practices. 
 
Methods: Field trials were carried out in two seasons, Summer and Kharif 2022, using a split-plot design with three tillage methods and four weed management practices. The treatments were replicated three times.&nbsp; 
 
Result: Among the different tillage treatments Mouldboard plough fb Cultivator fb Rotovator recorded the lowest weed density. With respect to weed management methods, pre- and post-emergence herbicide application and hand weeding at 20 and 40 DAS recorded the lower weed density. Interaction effects of tillage and weed management practices resulted in lower weed density in Mouldboard plough fb Cultivator fb Rotovator with herbicide application and Mouldboard plough fb Cultivator fb Rotovator with hand weeding. Highest weed density was recorded under Cultivator fb Rotovator in unweeded control. With respect to relative density, among the broad-leaved weeds (BLW) Trianthema portulacastrum and Dactyloctenium aegyptium in grasses dominated among the weed species in 30 and 60 DAS respectively. From the present study it was concluded that the Mouldboard plough fb Cultivator fb Rotovator with hand weeding twice or herbicide application reduces the weed emergence from the soil weed seed bank.

Above Ground Emergence and Floristic Composition of Weeds in Relation to Tillage and Weed Management Practices in Maize and Cowpea

<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 style="text-align: justify;">A field experiment was conducted during autumn, 2014 at ICR Farm, Assam Agricultural University, Jorhat, Assam to compare three different direct seeded upland rice varieties along with different integrated weed and nutrient management practices. The experiment was carried out in factorial randomized block design replicated thrice with 15 treatments involving 3 varieties: Inglongkiri, Maizubiron and Rasi along with 5 treatments of weed and nutrient management, i.e. 20-10-10 kg/ha N-P2O5-K2O + &nbsp;pretilachlor @ 750 g/ha followed by grubber 30 DAS (W1), 30-15-15 kg/ha N-P2O5-K2O + pretilachlor @ 750 g/ha followed by grubber 30 DAS (W2), &nbsp;10-5-5 kg/ha N-P2O5-K2O &nbsp;+ pretilachlor @ 750 g/ha followed by grubber 30 DAS + Vermicompost @ 1 t/ha &nbsp; (split equally at sowing &amp; 30 DAS) + Sesbania (Sesbania aculeata) green mulch (up to 30 days) (W3), &nbsp;10-5-5 kg/ha &nbsp;N-P2O5-K2O + pretilachlor @ 750 g/ha followed by grubber 30 DAS with intra-row spacing 15cm (W4), &nbsp;and 20-10-10 kg/ha N-P2O5-K2O + Weedy check (W5). The predominant weed floras observed in the experimental field were Ageratum conyzoides, Cynodon dactylon, Cyperus rotundus and Cyperus iria. Treatment W3 resulted significantly lowest weed population at all growth stages. Weed dry weight was significantly lowest with application of 30-15-15 kg/ha N-P2O5-K2O along with pretilachlor @ 750 g a.i./ha and grubber 30 DAS at 20, 60 DAS and at harvest of rice crop. The results revealed an increase in yields as evident by higher grain and straw yield for all the three varieties with pre-emergence application of pretilachlor (750g a.i./ha) + grubber 30 days after sowing + 30-15-15 kg/ha of N-P2O5-K2O.&nbsp;</div>

Weed dynamics and yield of direct seeded upland autumn rice (oryza sativa l.) Varieties as influenced by integrated weed and nutrient management practices