Response of Crop Establishment Methods and Weed Management Practices on Weed Flora, Crop Growth and Yield of Wheat in Maize-Wheat-Greengram Cropping System

Sustainable agriculture mostly relies on conservation tillage, crop residue retention and crop diversification. Weeds are major production hurdles in adoption of conservation agriculture (CA), therefore, weed management is important for sustainable crop yield. Designing efficient integrated weed management (IWM) practices under zero-tillage with crop residue (ZT+R) is helpful in getting optimum yield. A field experiment was carried out at research farm of ICAR-Directorate of Weed Research, Jabalpur (M.P.), India with eight treatment combinations, two crop establishment methods (conventional tillage and conservation tillage) in main plots and four weed management practices (weedy check, recommended herbicide, IWM, and herbicide rotation) in sub-plots were evaluated using a split plot design with three replications. The results indicated that the wheat sown under ZT+R led to significantly less weed density (105.9 no. m-2 in 2020-21 and 122.8 no. m-2 in 2022-23) and biomass (149.7 and 174.2 g m-2, respectively) hence, registered the highest weed control efficiency (WCE, 72.3% and 71.2%, respectively). Higher WCE helped in producing better wheat growth indices like plant height (106.3 and 101.1 cm, respectively), biomass (12.0 and 9.0 g plant-1, respectively) and no. of tillers (488.0 and 391.3 no. m-2, respectively) ultimately grain yield (4164 and 3814 kg ha-1, respectively) and straw yield (7265 and 6834 kg ha-1, respectively) compared with conventional tillage during both the years. Among the weed management practices, ready-mix application of clodinafop + metsulfuron at 60+4 g ha-1 (30-35 days after sowing, DAS) followed by (fb) hand weeding at 45 DAS increased growth indices like plant height (110.2 and 105.0 cm, respectively), plant biomass (14.9 and 12.1 g plant-1, respectively) and no. of tillers (547.2 and 436.7 no. m-2, respectively) ultimately grain yield (4708 and 4299 kg ha-1, respectively) and straw yield (7836 and 7610 kg ha-1, respectively), and WCE (97.4% and 96.8% respectively) with significantly less weed density (25.7 and 35.0 no. m-2, respectively) and biomass (13.6 and 19.9 g m-2, respectively) at 90 days after sowing. IWM also completely reduces the weed density and biomass over the other weed management practices during both the years. Therefore, wheat sown under ZT+R coupled with IWM was superior in terms of weed control, crop growth and yields.

Conservation Agriculture as a Climate Change Mitigation Strategy: A Review

To enhance our comprehension of agriculture's role in addressing climate change, accurate assessment of its capacity for carbon sequestration is crucial. This assessment encompasses multiple considerations, including regional climate patterns, crop choices, soil management practices, and soil types. Climate change poses a significant threat to food and nutritional security on local, national, and global scales. The amplified concentrations of greenhouse gases, such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), present immediate challenges. Vulnerable populations, especially those in impoverished conditions, face heightened risk of food insecurity due to the impacts of climate change. Additionally, the conversion of non-agricultural land, like forests, into agricultural use, and human-generated emissions of greenhouse gases from agricultural activities significantly contribute to climate change. The escalating concentration of greenhouse gases, particularly CO2, in the atmosphere leads to global warming. Over the last century (1906–2005), the global mean surface temperature has risen by approximately 0.60 to 0.90°C, with the most rapid increase occurring in recent decades. The global average temperature continues to steadily climb and is projected to rise by 2°C by 2100, potentially resulting in significant global economic losses. The increasing concentration of CO2, a major greenhouse gas, is a cause for concern. This rise has fostered enhanced plant growth and productivity due to increased photosynthesis. However, the benefits of heightened photosynthesis are offset by higher temperatures, leading to increased crop respiration rates, greater evapotranspiration, heightened pest infestations, shifts in weed species, and reduced crop durations. This paper reviews the literature on climate change, its potential drivers, its effects on agriculture, and its influence on the physiological and metabolic processes of plants. It also explores potential and reported implications for plant growth, productivity, and mitigation strategies. In recent years, there has been a growing recommendation for the adoption of conservation agriculture as a more sustainable alternative to conventional farming practices. Conservation agriculture not only supports soil health but also enhances agricultural productivity, making it a crucial tool for mitigating the impacts of climate change.

Effect of Tillage and Weed Management Practices on Growth and Yield Attributes of Wheat (Triticum aestivum L.)

A field experiment was conducted during the Rabi season of 2017-18 at Acharya Narendra Deva University of Agriculture & Technology, Kumarganj, Ayodhya 224229 (U.P.) to study the effect of various tillage and weed management practices on growth parameters, yield attributes and yield of wheat crop. The combination of treatments were five tillage system in main plot viz., TPR-CT, W-CT (T1), TPR-CT+W-ZT+S-ZT (T2), DSR-CT+W-CT+S-ZT (T3), DSR-ZT+W-ZTR+S-ZT (T4) and DSR-ZTR+W-ZTR+S-ZT (T5) and three-level of weed management practices in sub plot viz., Clodinafop + metsulfuron @ 60 + 4g/ha at 30 DAS (W1), Clodinafop + metsulfuron @ 60 + 4g/ha at 30 DAS fb 1 hand weeding at 45 DAS (W2) and 1 hand weeding at 45 DAS (W3) in wheat were tested with 3 replication in split-plot design. The soil was silt loam in texture and medium in fertility status. Among various tillage and weed management practices DSR-ZT+R, W-ZT+R, S-ZT (T5) and Clodinafop + metsulfuron 60 + 4g/ha at 30 DAS fb 1 hand weeding at 45 DAS (W2) resulted in lowest in total weed density and total weed dry weight (g/m2) and highest values of growth parameters, yield attributes and yield in comparison to other tillage practices and weed management practices.

Conservation Agriculture: A Long-term Approach towards Sustainability

With the application of intensive agricultural techniques, conventional agriculture has been successful in meeting production goals but has also led to the depletion of natural resources. Sustainability in the management of the natural resource base is necessary for ongoing and expanded agricultural output to provide food security for future generations. Over a long period, the traditional tillage practice has led to the destruction of the natural resource base of the land. As a result of its inherent connection to the physical, chemical, and biological aspects of soil, it has led to a significant loss of soil and SOM, which is a crucial component of soil quality. Therefore, a suitable cropping system and land use must be implemented and adopted to ensure food security on a sustainable basis. These measures should be based on principles to prevent land degradation, protect the natural resource base, and improve food and nutritional security through crop diversification and optimal rotation. The one sustainable cropping method that may reverse soil erosion, increase crop output, and improve the socioeconomic status of small landholder farmers is conservation agriculture (CA). Conservation agriculture (CA) is the integrated management of the available natural resources such as soil, water, flora, and fauna, with certain outside inputs to maximize the effectiveness of natural resource utilization. To fulfill the objective of sustainable crop production, an alternative approach known as conservation agriculture has emerged. It represents a significant advance in the direction of sustainable agriculture. This article reviews the emerging concerns due to the continuous adoption of conventional agriculture systems, contrasting features between conventional and conservation agriculture systems, and various principles and practices in conservation agriculture. It also highlights the benefits and limitations of CA and various challenges in the adoption of CA.

Stocks and Distribution of Soil Carbon, Nitrogen, Phosphorus and Sulfur in an Integrated Crop-Livestock System Treated with Phosphates

Abstract Conservation agriculture practices can contribute to changes in soil nutrient dynamics over time. This experiment evaluated the changes in total stocks and distribution of carbon, nitrogen, phosphorus and sulfur concentrations in soil, during 60 months, in an integrated crop-livestock system (ICLS) due to anticipated fertilization of sources and doses phosphates applied in soil surface. The experiment was conducted over a period of five years, under Typic Dystrudept, using a randomized block design, in an incomplete factorial scheme (3×3+1), with four replications. Treatments consisted of three sources of P [triple superphosphate (TSP), rock phosphate - Arad (RP) and magnesium thermophosphate (MTP)], along with four doses of P (0, 60, 120 and 180 kg ha-1 P2O5 total). Samples of soil were collected in 0-5, 5-10, 10-15, 15-20 and 20-30 cm layers at 24, 36, 48 and 60 months after beggining of experiment where the following chemical attributes were evaluated: (i) total organic carbon (TOC); (ii) total nitrogen Kjeldahl (TNK); (iii) available P by ion exchange resin method (P-IER); and (iv) available S-SO4 2-. The ICLS conditions provided increased total stocks and concentrations of TOC, TNK, P-IER and S-SO4 2- over time. The applications of different phosphates had no influence on soil TOC concentrations during the five years of experimentation. The concentrations of TNK, P-IER and S-SO4 2- showed an increase in different layers of soil, with the application of sources and doses of P. The P fertilization practice that was anticipated can consist of an efficient management of soil fertility, using properly managed conservation systems.

Economic profitability of crop rotation systems in the Caiuá sandstone area / Rentabilidade econômica de sistemas de rotação de culturas em área de arenito Caiuá

ABSTRACT: Even in areas of predominance of Caiuá sandstone, with soils of low natural fertility that are highly susceptible to erosion and degradation processes, farmers have adopted systems with little diversification, because they believe that they provide a greater economic return. However, agricultural practices such as crop rotation can bring agronomic benefits in terms of conservation agriculture, in addition to economic gains, circumventing edaphoclimatic difficulties in the region. In this context, the objective of this study is to verify whether no-till crop rotation systems are economically profitable, in a Caiuá sandstone area in the northwest region of the Brazilian state of Paraná. To this end, an experiment was conducted in the municipality of Umuarama, state of Paraná, in the crop year 2014/15 to 2016/17. The experimental design used random blocks, with four treatments and four repetitions. The treatments consisted of four crop rotation systems, involving wheat, black oats, canola, safflower, rye, crambe, beans, maize, fodder radish, soybean, sorghum, lupin beans, buckwheat, and triticale cultivars. Crop yields, operating costs, income, and net farm income were assessed. From the results, it was reported that the highest income was obtained in the systems that adopted the largest number of winter and summer commercial crops. Only one treatment was profitable, that is, it had a positive net farm income. This scenario may be associated with the fragility of the region's soil, which having low fertility, requires a high investment in fertilization and liming to ensure adequate production.

RESUMO: Mesmo em áreas de predomínio do arenito Caiuá, com solos de baixa fertilidade natural e altamente susceptíveis a processos de erosão e degradação, agricultores têm adotado sistemas com baixa diversificação, por acreditarem que estes apresentam maior retorno econômico. No entanto, práticas agrícolas como a rotação de culturas podem trazer benefícios agronômicos, relativos à agricultura conservacionista, além de ganhos econômicos, contornando dificuldades edafoclimáticas da região. Neste contexto, o objetivo deste estudo foi verificar se na região Noroeste do Paraná, em área de arenito Caiuá, sistemas de rotação de culturas sob plantio direto apresentam rentabilidade econômica. Para tanto, foi conduzido um experimento no município de Umuarama, estado do Paraná, entre anos agrícolas de 2014/15 a 2016/17. O delineamento experimental foi de blocos ao acaso, com quatro tratamentos e quatro repetições. Os tratamentos constituíram-se de quatro sistemas de rotações de culturas, que envolveram cultivares de trigo, aveia preta, canola, cártamo, centeio, crambe, feijão, milho, nabo forrageiro, soja, sorgo, tremoço, trigo mourisco e triticale. Foram avaliadas as produtividades das culturas, os custos variáveis, as receitas e as margens brutas. A partir dos resultados, verificou-se que as melhores receitas foram obtidas nos sistemas que adotaram o maior número de culturas comerciais de inverno e verão. Somente um tratamento apresentou rentabilidade, ou seja, margem bruta positiva. Este cenário pode estar associado à fragilidade do solo da região, que por serem de baixa fertilidade, demandam alto investimento com adubação e calagem, para garantir uma produção adequada.

El IMPERATIVO DE LA AGRICULTURA HOY: CUIDAR LA TIERRA / THE IMPERATIVE OF AGRICULTURE TODAY: LAND CARE

Desde que los humanos adquirieron conciencia de sus actos han generado relaciones de diverso orden con la tierra y sus habitantes. Con la emergencia de la agricultura, la tierra, de ser un bien libre y disponible para todas las criaturas vivientes, pasó a ser apropiado por los seres humanos para satisfacer necesidades. La tierra adquirió un valor utilitario, para producir alimentos y materias primas, y generar renta y poder político. No obstante, para los campesinos y pueblos indígenas, la tierra, además ha tenido y aún tiene un valor afectivo y sagrado. En esta lógica, la agricultura se constituye en vínculo de los seres humanos con la tierra, que conlleva un imperativo ético: cuidar la tierra, en tanto que esta es uno más de los sujetos de la comunidad ética. En este orden de ideas, este artículo discute el cuidado de la tierra como imperativo ético de la agricultura. Para ello, se analizan y discuten visiones de preservacionistas con visiones técnico-científicas de conservación de suelos.

Since humans became conscious of their actions they have generated relationships of various kinds with land and its inhabitants. With the emergence of agriculture the land, being a free good available for all living creatures, became appropiated by humans to satisfy their needs. The land acquired a utilitarian value to produce food and raw materials, and generate income and political power. However, for farmers and indigenous people land also has had and it still has an affective and sacred value. In this logic, agriculture constitutes a bond of human beings with the land, which embraces an ethical imperative: land care while it is just one other subject of the ethical community. In this order of ideas, this article discusses land care as an ethical imperative of agriculture. To do this, visions of preservationists with technical-scientific views of soil conservation are analyzed and discussed.

Evaluating Climate Change Mitigation and Adaptation Potential of Conservation Agriculture in Semi-arid Tropics of Southern India.

Aims: As climate change related rainfall and temperature variability is being increasingly experienced in the SAT regions, we assessed climate change mitigation and adaptation potential of Conservation Agriculture (CA) by studying effects of minimum tillage (MT) and residue management practices on rain water use efficiency (RWUE), soil moisture, runoff, energy use and carbon dioxide emission in two maize-legume cropping systems. Study Design: The experiment was laid out in split-split plot design with four replications. Place and Duration of Study: The study was conducted at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) farm, Patancheru, Telangana, India during 2010-11 and 2011-12. Methodology: RWUE was calculated as maize equivalent yield divided by rainfall received during the crop season. Integrated digital runoff and soil loss monitoring unit (IDRSMU) was used to measure runoff. Soil moisture content was measured using the gravimetric method (0-30 cm depth) and neutron probe (60-90 cm depth). The soil organic carbon was analyzed following the Walkley-Black method [1]. The diesel consumption in MT and conventional tillage (CT) was estimated following Downs and Hansen (http://www.ext.colostate.edu/pubs) and emission of CO2 was estimated according to EPA, 2009 [2]. Results: Tillage and residue management practices did not show significant effect on RWUE except; CT having significantly higher RWUE over MT during 2011-12. Effect of cropping systems on RWUE was significant but variable during the two years of study. MT-RT (minimum tillageresidue retained) reduced total seasonal runoff by 28.62% and 80.22% compared to CT-RR (conventional tillage- residue removed) in 2010-11 and 2011-12, respectively. Similarly, MT-RT reduced rainwater loss and peak rate of runoff compared to CT-RR in both the years of study. During 2010, MT-RT had higher total soil moisture (v/v) in the 0-90 cm soil depth in sole as well as intercropped maize compared to CT-RR, however, during 2011 MT-RT had higher total soil moisture in sole maize only. As compared to CT, even though, MT improved SOC in 0-15 cm depth but lowered slightly in 15-30 cm depth. RT (residue retained) improved SOC in 0-15 and 15- 30 cm depths compared to residue removal (RR). MT-RT had higher or equal SOC in 0-15 and 15- 30 cm soil depths compared to CT-RR in both the maize-legume cropping systems. MT saved energy corresponding to 41.49 l of diesel per hectare annually compared to CT. Similarly, MT emitted 110.79 kg less CO2 annually on per hectare basis compared to CT due to reduced diesel use. Conclusion: CA, when adopted by following good agricultural practices and refined to suit the local conditions, could emerge as sustainable production system for climate change mitigation and adaptation of dryland cropping systems in semi-arid tropics of southern India.

Caracterização e estoques de carbono de sistemas agroflorestaisno Cerrado de Minas Gerais / Characterization and carbon storage of agroforestry systems in brazilian savannas of Minas Gerais, Brazil

Os sistemas agroflorestais (SAFs) além de geração de renda e conservação da biodiversidade pode ser uma alternativa para a estocagem de carbono. O trabalho teve como objetivo caracterizar três sistemas agroflorestais (SAFs) e estimar os estoques de carbono na fitomassa aérea, na serapilheira e no solo. Os SAFs e suas respectivas vegetações nativas adjacentes foram caracterizados quanto ao número, classificação botânica,distribuição diamétrica e estratificação vertical dos indivíduos arbóreose. Em cada um dos sistemas, foram estimados os estoques de carbono na fitomassa aérea, na serapilheira e no solo. Os SAFs,implantados a partir do manejo da vegetação nativa, apresentaram uma biodiversidade vegetal e estoque de carbono na fitomassa, na serapilheira e no solo semelhantes à área de vegetação nativa adjacente. Por outro lado, os estoques de carbono no SAF implantado em área anteriormente cultivada com culturas anuais apresentou menor diversidade de espécies arbóreas e estoques de carbono na fitomassa, serapilheira e no solo, em relação à vegetação nativa adjacente. Sistemas agroflorestais bem manejados se assemelham à vegetação nativa em estoque de carbono e conservação da biodiversidade dos recursos naturais.

Agroforestry systems (SAFs) as well as income generation and biodiversity conservation can be an alternative to carbon stocks. The study aimed to characterize and estimate the soil and plant carbon stocks of SAFs in Brazilian savannas of Minas Gerais State, Brazil. Three agroforestry systems and their adjacent native vegetation were evaluated. In addition, the forest inventory, the diameter distribution and vertical stratification of tree species were measured. The SAFs deployed from the management of native vegetation had a plant biodiversity and carbon stock in biomass, litter and soil similar to that of the adjacent area of native vegetation. On the other hand, carbon stocks in SAF deployed in the area cultivated with annual crops had lower species diversity and carbon stocks in biomass, litter and soil in relation to native vegetation adjacent. Agroforestry systems well managed have carbon stocks and biodiversity of natural resources like native vegetation.