Crop Production Research Papers - Academia.edu (original) (raw)

Combustion of coal for production of electricity in the United States often requires the removal of SO 2 produced in the flue gas in order to meet clean air regulations. Some scrubbing technologies lead to the production of large amounts of flue gas desulfurization (FGD)-gypsum. Gypsum is a soluble source of the plant nutrients Ca and S and can also improve the physical and chemical properties of soils. However, there are few reports on the use of FGD-gypsum for enhancement of crop growth or soil quality in agriculture. FGD products, used as S fertilizers, were applied at a rate of 30 lbs S/acre to an agricultural soil (Wooster silt loam, Typic Fragiudalf). Corn (Zea mays) grain yield was statistically (P ≤ 0.05) increased by 18.3% in 2002 and 6.6% in 2003 as compared to a no-treatment control. Based upon measurements of soil chemical properties, the quality of a Blount soil (Aeric Epiaqualf) in Ohio was improved by application of 1,500 to 3,000 lbs of FGD-gypsum/acre. Water-soluble Ca and S were increased to a depth of 80 cm and exchangeable Al was decreased between 10 and 40 cm depth. Preliminary results of an economic analysis suggested that a gypsum/no-tillage crop production system had economic advantages compared to a no gypsum/conventional tillage system for soybean production.

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- Economic analysis, United States, Crop Production, Soybean

The Indian government imposed a ceiling on the price of Bt cotton seeds in 2006. This paper aims to analyze the effect of such price intervention on the diffusion of Bt cotton in India. Using three variations of dynamic logistic models, diffusion paths in nine major cotton growing states from 2002 to 2008 are studied. It was found that although seed prices were significant in impacting the diffusion rates, the effect was limited. It was also found that varietal approval is an important factor affecting diffusion rates.

- by anchal arora
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- Applied Economics, Panel Data, Research and Development, Crop Production

This paper deals with the effects of agronomic practices on parasite life cycles, and the design of integrated crop protection strategies. Cropping systems have a large effect on the size of the primary inoculum and its localisation, on the development and spread of epidemics, and on the coordination of the life cycle of cultivated plants and that of their parasites. They can disrupt ecological equilibria, either favouring or disfavouring the pathogens. By combining information concerning the effects of agricultural techniques on diseases and the physiological effects of diseases on growth and crop production, it is now possible to develop new crop management systems, in which the use of non-chemical methods for preventing diseases is a priority. However, the current knowledge need to be completed by studies on other scales, particularly of the effect of cropping systems on the genetics of disease populations integrating more completely the 'long-term' dimension of sustainable agriculture. To cite this article:

- by Meynard Jean-marc
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- Genetics, Sustainable agriculture, Agriculture, Fungi

Toxicities of new chemistries viz. fipronil, chlorfenapyr, indoxacarb, spinosad, abamectin and emamectin benzoate, having novel modes of action, were evaluated using an IRAC leaf-dip method against Pakistani field populations of Helicoverpa armigera, which were highly resistant to conventional chemistries. Whereas the majority of populations exhibited susceptibility close to the baselines, there were, nevertheless, signs of resistance development to the new chemistries as demonstrated by a low level of tolerance in many populations. This may be due to a cross-resistance from the resistance mechanisms, particularly metabolic, already selected against older chemistries. If used judiciously and in rotation, the new chemistries can restore the profitability of crop production by counteracting and preventing insecticide resistance in H. armigera and other pests in the future.

- by zahoor ahmad
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- Zoology, Biology, Insecticide Resistance, Profitability

Eight trace elements are essential for higher plants: boron (B), chlorine (Cl), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni) and zinc (Zn). Whenever the supply of one or more of these elements is inadequate, yields will be reduced and the quality of crop products impaired, but crop species and cultivars vary considerably in their susceptibility to deficiencies. Zinc deficiency is the most ubiquitous micronutrient problem throughout the world affecting many crops including the staples maize, rice and wheat. Boron deficiency is the second most widespread micronutrient problem and dicotyledon species tend to be more sensitive to B deficiency than graminaceous crops. Iron deficiency is important in some regions, especially those with a Mediterranean climate and calcareous soils. Copper deficiency is important in some parts of the world, such as Europe and Australia where cereals are most affected. Likewise, Mn and Mo deficiencies vary in importance around the world. Acute micronutrient deficiencies in plants are accompanied by distinct symptoms, but hidden deficiencies without obvious symptoms are generally more widespread.

- by Xiaopeng Gao
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- Crop Production, Experimental agriculture

Organic farming offers an alternative that can eliminate many of the environmental problems of conventional agriculture in the industrialized world. Instead of using petroleum-derived chemicals to fertilize and protect crops, farmers manage their fields so as to take advantage of naturally-produced composts and mulches that recycle nutrients, and control pests and weeds. However, organic farming is often logistically inefficient, because these organic composts and mulches are bulky and difficult to transport. Alleycropping as practiced in the tropics may be able to make organic farming more efficient in the southeastern United States. In this form of alleycropping, trees or shrubs, often leguminous, are planted in hedgerows between open spaces ('alleys') where the crop is grown. The hedgerow species are periodically pruned (both aboveground and belowground), and prunings fall directly onto or into the soil where the crop is growing. These prunings add carbon and nutrients to the soil, and provide mulch that helps suppress weeds. Use of prunings reduces the need for composting and hauling manures and mulches, thereby increasing the efficiency by which organic material is supplied to the soil that supports the economic crop. In Georgia, dry weight annual production of prunings reached up to 18.4 Mg ha −1 , a quantity high enough to maintain crop production. Thus, alleycropping may be feasible for organic farmers in the southeastern United States.

- by Carl Jordan
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- Organic Farming, Crop Production, Open Space, Green Manure

The paper estimates the effect of soil degradation on crop yields for dominant cereals in Ethiopia at a nationwide level and analyses its relation with population density and fertiliser use. A soil degradation index is derived from an ordered qualitative classification on the degree of soil degradation and the area extension. Biophysical variability is incorporated by using, as dependent variable, the yield ratio (actual/potential yield) to correct for agro-climatic and crop genetic differences, and by including soil fertility as explanatory variable. The data set is cross sectional and obtained from gridded overlays on soil degradation, climate, soil, land form, population (and cattle) density. The relationships are estimated via non-parametric (kernel density) regression and the estimation results are depicted in 3-D graphs. It appears that the relationship between yield ratio, land degradation and soil fertility is not very strong. Yet, three stylised facts can be identified. First, land degradation has its major impact on soils of lower fertility, where population levels are low. Secondly, on fertile soils, land degradation is largely compensated by fertiliser application. Finally, most people can be found on the slope facing a deep and dangerous precipice. A spatial representation of the elasticity of crop productivity with respect to soil degradation indicates that most vulnerable areas are located in the northern part of the country.

- by Michiel Keyzer
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- Genetics, Spatial Representation, Crop Production, Population Density

Soil erosion, associated with environmental impacts and crop productivity loss, is usually considered the most impacting of surface hydrology processes. Runoff plays a major role in the erosion process, but it is also important by itself as it directly influences several surface hydrologic processes. In this paper, a computer interface (Erosion Database Interface, EDI) is described that allows processing the surface hydrology output database of the Water Erosion Prediction Project (WEPP) erosion prediction model, resulting in a georeferenced estimation of runoff. WEPP output contains non-georeferenced daily information about estimated runoff at the lower end of each Overland Flow Element. EDI, when running with WEPP, allows extracting WEPP-calculated runoff values, transforming them into annual means and relocating them in a georeferenced database readable by Geographic Information Systems (GIS). EDI was applied to a 1990 ha watershed in southeast Brazil, with vegetation of mainly sugarcane, forest, and pasture. A 100-year climate simulation was used as input to WEPP, and erosion values were calculated at about six points per hectare and interpolated to a raster format. EDI was successful in preparing the database for automatic calculation of erosion and hydrologic parameters with WEPP and to restore georeferences to mean annual accumulated runoff data that were imported in the GIS as a vector database. Of all the resulting maps, the runoff map is the one that integrates all of the input parameters required for WEPP simulation, thus reflecting not only the physical environment but also crop growth and management and tillage operations. A very small correlation between runoff and erosion shows them to behave independently. Moreover, it is concluded that on analyzing runoff related to agricultural management, georeferenced runoff studies are especially important. In this context, EDI may be a useful tool to assess the effect of tillage and crop management on runoff production. r

- by Elke Bloem
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- Engineering, Earth Sciences, Computers, Soil Erosion

Discussion on plant genetic engineering has experienced increasing momentum with the introduction of Genetically Modified (GM) corn in Germany and other European countries. This paper determines the various groups of German farmers, their attitudes and expected decisions on the use of GM foods using cluster analysis of 370 German farm managers. The results of cluster analysis indicate five main farmer groups who differ in terms of certain demographic characteristics and attitudes towards GM adoption. The study proposes tailored communication and risk management as an important measure that can be used by the biotechnology advocates to improve the level of acceptance.

- by Prof. Dr. Julian Voss
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- Food Policy, Biotechnology, Food Security, Genetic Engineering

Efficient plant nutrition management enhances and sustains agricultural production and safeguards the environment. Developing a suitable nutrient management system that integrates use of vermicompost and Bio-N may be a challenge to reach... more

- by Biley Temanel and +1
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- Crop Production

Nitrogen fertilization and winter pruning are commonly used to control crop production in peach [Prunus persica (L.) Batsch] orchards. They are also known to affect the dynamics of Myzus persicae (Sulzer) (Homoptera: Aphididae) aphid populations via bottom-up regulation processes. Interactions between crops and pests can cause complex system behaviour in response to management practices. An integrated approach will therefore improve the understanding of the effects of these two cultural practices on aphid and peach performances.

- by Nadine Hilgert
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- Pest Management, Modeling, Interaction, Population Dynamics

A water simulation model (WaSim) to simulate the growth and development of Amaranthus cruentus as well as the components of water balance for a typical sandy-clay-loam soil of Akure has been described. Dry season experiments were carried between January and March of 2005 and 2006. Amaranthus seeds were established on the field and three irrigation water managements were imposed on the crop to determine its response to water deficit at its different phenological stages. Amaranthus growth and development, evapotranspiration (ET) and rooting depth were calibrated by fitting the most sensitive variables to obtain the corresponding model output. The model simulated crop growth and crop cover well, the coefficient of determination r 2 =0.9 and the difference between simulated and measured root depth is not significant at P<0.001. The actual evapotranspiration (AET) from the model prediction and the measured value gave a fairly high coefficient of correlation r=0.7 at P<0.001. The mean bias error (MBE) and the root mean square error of yield estimates between the measured and the model prediction are -0.4444 and 1.35 respectively at P < 0.001. The model was considered effective and appropriate for daily simulation of water balance, water requirement of crops and in climate effects on crop production.

- by Johnson Fasinmirin
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- Soil moisture, Evapotranspiration, Growth and development, Water balance

This study measured the economic impacts of climate change on crop and livestock farming in Africa based on a cross-sectional survey of over 8000 farming households from 11 countries in east, west, north and southern Africa. The response of net revenue from crop and livestock agriculture across various farm types and systems in Africa to changes in climate normals (i.e. mean rainfall and temperature) is analysed. The analyses controlled for effects of key socioeconomic, technology, soil and hydrological factors influencing agricultural production. Results show that net farm revenues are in general negatively affected by warmer and drier climates. The small-scale mixed crop and livestock system predominantly typical in Africa is the most tolerant whereas specialized crop production is the most vulnerable to warming and lower rainfall. These results have important policy implications, especially for the suitability of the increasing tendency toward large-scale mono-cropping strategies for agricultural development in Africa and other parts of the developing world in light of expected climate changes. Mixed crop and livestock farming and irrigation offered better adaptation options for farmers against further warming and drying predicted under various future climate scenarios.

- by r hassan
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- Earth Sciences, Climate Change, Agricultural Development, Agriculture

Characterizing the carbon footprint (CF) of agricultural production offers key information for pursuing low carbon agriculture and food consumption. While China has long strived for increasing food production capacity for its large and still growing population, the high emissions cost, especially from the over use of agro-chemicals, has been widely debated for the last decade. However, the CF of China's crop production has not yet been assessed. This paper reports a basic estimate of CF of crop production using national statistical data available for the period of 1993-2007. The dataset includes the amount of individual agricultural inputs (fertilizer, pesticide, diesel, plastic film, etc.), cultivation area and total of production whole crops. Using the emission factors estimated for China's agricultural features and available abroad, the mean overall CF of China's crop production was estimated to be 0.78 ± 0.08 tCE ha −1 yr −1 and 0.11 ± 0.01 tCE t −1 yr −1 , for land use and bulk production respectively. For the duration the data covered, the carbon intensity under cultivation land use was seen to increase since 1993. Among the total, fertilizer induced emissions exerted the largest contribution of ∼60%, being 0.45 ± 0.04 tCE per ha and 0.07 ± 0.01 tCE per ton of production, on average. Compared to the UK, the estimated overall CF of China's crop production was higher in terms of cultivation land use. While there was a significant positive correlation of carbon intensity with total production, carbon efficiency was shown in a decreasing trend during 2003-2007. Therefore, low carbon agriculture should be pursued, and the priority should be given to reducing fertilizer application in agriculture of China. However, for developing best management practices for climate change mitigation in crop production of China, further studies of crop and regional specific CFs and the variation with climate conditions and agricultural managements are needed.

- by Kun Cheng
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- Carbon Footprint, Environmental Sciences, Climate Change Mitigation, Food Consumption

Ensuring acceptance of dedicated biomass feedstocks by landowners, agricultural communities, environmental and public interest groups, requires that the environmental benefits, concerns, and risks associated with their production be quantified. Establishment and management measures to benefit soil and water quality are being identified by ongoing research. Field studies are showing that nutrients are retained within the rooting zone of dedicated feedstocks, subsurface herbicide transport does not occur, and off-site chemical transport is minimal compared with traditional agricultural crops. The amounts and timing of fertilizer application were critical to minimizing off- site transport of nutrients. Maintaining soil cover decreased runoff, sediment losses, and nutrient transport compared with traditional agricultural crops. Conversion of traditional croplands to biomass and no-till crop production improved soil quality and soil carbon storage. Subsurface nutrient losses were less fr...

Climate models indicate that there will be an increase in both average annual temperature (+4.5 o C) and rainfall in the Midwestern U.S. by the year 2050 which may result in warmer, wetter conditions. Perhaps the most important factor will be less predictable weather patterns that will emerge, increasing the frequency of extreme weather events such as heavy downpours of precipitation, late season frosts and droughts. For example, July rainfall may increase 20% and might come in just two rainfall events. This study combines expertise from several disciplinary areas with modeling strategies to assess the impact of global climate change on midwestern agriculture. Predictions of warmer summers, wetter springs, and more extreme events indicate that the cropping system may need to be adjusted to effectively conserve soil, maintain timely planting, avoid early season frost damage, and respond to warmer growing conditions. Climate projections (HADCM2), crop growth models (DSSAT), the Water ...

- by Otto Doering
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- Genetics, Climate Change, Seasonality, global Climate change
- by Jane Southworth
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- Genetics, Climate Change, Seasonality, global Climate change
- by Evert Van der Sluis
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- International Relations, World Trade Organization, Crop Production, Soybean

This work was focused on the assessment of changes occurring in crop production and climate during the 20th century in Argentina. The study was carried out for nine sites located in the Pampas region that are representative of contrasting environments. We have considered the four main crops cultivated in this area (wheat, maize, sunflower and soybean). Historical climatic data and crop production related variables (yield, planted area, harvested area) were analyzed and, by means of crop simulation models, we quantified the impact of climate on crop yields. Changes occurring in climate during the three last decades of the 20th century were characterized by important increases in precipitation especially between October and March, decreases in maximum temperature and solar radiation in particular during spring and summer and increases in minimum temperature during almost all of the year. These changes contributed to increases in yields, especially in summer crops and in the semiarid zone, mostly due to increases in precipitation, although changes in temperature and radiation also affected crop yields but to a lesser extent. Comparing the period 1950-1970 with 1971-1999, yields increases attributable to changes in climate were 38% in soybean, 18% in maize, 13% in wheat, and 12% in sunflower while mean observed yield increases were 110% for maize, 56% for wheat and 102% for sunflower.

- by Graciela Odilia Magrin
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- Multidisciplinary, Maize, Crop Production, Soybean

Contrary to irrigated agriculture thet use blue water, rainwater haNesting that use green water in forms of the direct rain and runoff, has been accorded little importance in terms of economic research, investment, technology transfer and management. This bias happens whereas 60-70 per cent of food production is rain fed and based on green water. The perception by majority of our water planners has been that, water haNesting in the upper watersheds would reduce blue water flows downstream. Improved management of rainwater in the upper watersheds for agriculture, livestock and domestic use would reduce pressure on the blue water downstream. However, the promotion of rainwater haNesting in the upper watersheds requires an ex-ante analysis related aspects of economic benefits, eco-hydrology and human dynamics. This paper demonstrates the economic benefits of rainwater management for crop production in a semi-arid Makanya Watershed in the Pangani river basin. The results from a two-seasons yield monitoring done between 2002 to 2004 for maize and lablab show that, rainwater haNesting has the potential for poverty reduction through improved yields, returns to land and labour. These findings justify investment and technology transfer1n rainwater haNe~ting for crop production in the upper watersheds of our major river basins.

- by henry mahoo
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- Civil Engineering, Water Availability, East Africa, Technology transfer

The application of soil solarization (SS), one of the most promising techniques for the control of soilborne pathogens, is seriously limited by the drawback regarding the disposal of the used plastic materials. A possible solution to this problem is the use of biodegradable plastics. The aim of this study was to make comparisons between the impact of SS performed with biodegradable materials and that of SS with plastic films and other pest management techniques (i.e. organic matter amendment, calcium cyanamide and Dazomet fungicide application) on crop productivity, soilborne disease incidence, weed suppression, and soil chemical (total N, NH 4 -N, nitrate, available phosphorus, organic matter, hydrolysis of fluorescein diacetate) and microbial (cultivable Pseudomonas, DGGE fingerprinting of bacterial 16S-and fungal 28S rRNA gene fragments from total soil community DNA) parameters. We carried out field experiments in two types of soil with different textures (clay and sand) artificially inoculated with Fusarium oxysporum f.sp. lycopersici (vs. tomato) and Sclerotinia minor (vs. lettuce). The temperature of soils covered with solarizing materials was always higher than that of bare soils, but plastic cover was more effective and consistent in rising soil temperature compared to biodegradable materials. Plant growth promotion by SS was limited, especially compared to Dazomet and organic matter applications, and a positive effect was observed only for lettuce in the clay soil. Differently, both plastic and biodegradable solarizing materials were effective in reducing lettuce drop caused by S. minor. Weed development was significantly suppressed by Dazomet application and SS with plastic film, while control with biodegradable materials was limited. SS had a variable and limited effect on chemical and microbial parameters, with a general tendency to reduce richness of bacteria and fungi. Dazomet caused the most pronounced reduction of the microbial community diversity in both soil types and a significant stimulation of the fluorescent Pseudomonas group. Organic amendment significantly enhanced the organic matter content, the hydrolysis of fluorescein diacetate and the Pseudomonas population. Among all measured soil parameters, the size of the fluorescent Pseudomonas population emerged as the most important factor affecting crop productivity. The results of this experimentation show the potential of using biodegradable solarizing materials in place of plastic films, but also indicate the need for improving their properties to obtain performances comparable to those of other pest management techniques.

- by Giancarlo Moschetti
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- Pest Management, Biological Sciences, Environmental Sciences, Crop Production

Borana pastoralists in southern Ethiopia are faced with the challenge of developing more efficient and sustainable use of natural resources. In past decades poorly adapted development interventions and inadequate land-use policies aggravated by population growth have weakened pastoral rangeland management. Ignoring pastoralists’ technical and organizational capacities has contributed to progressive land degradation, the erosion of social structures and poverty. The Endogenous Livestock Development concept recognises pastoralists’ indigenous knowledge-based strategies and priorities, and uses them as the bases for further development of their production system and social relations, to be utilized, improved and combined with modern technologies. This paper explores the Borana pastoralists’ adaptive strategies for improved utilization of natural resources and the manner in which they respond to environmental risk and external influences such as water development and new formal administ...

- by Sabine Tui
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- Human Ecology, Institutional Change, Indigenous Knowledge, Natural Resource Management

This paper examines whether poor and vulnerable groups in society share in the benefits of a foreseen economic expansion in the demand for fruit, vegetables and flowers from consumers at home and abroad. Primary survey data is collected on the differentiated position of low-income households in different supply structures (with varying levels of vertical coordination) and markets (national, regional and international markets). The data support the following hypotheses: (i) For many resource-poor agents, horticulture-related activities make substantial contributions to their livelihood security-certainly in the short term. (ii) Farming, trading services, small-scale retail, and farm labour are activities to which members of resource-poor and economically vulnerable households have the best access given their endowments. (iii) A move from food production for home consumption towards cash crops or off-farm labour is supported when there are sufficient options to reduce livelihood risk in the household. (iv) Both value creation and the generation of opportunities for (self-) employment in domestic marketing channels are substantial, and possibly outweigh the economic impact of overseas export marketing. Policy support is best tailored to specific conditions and specific actors to achieve a maximum impact on poverty alleviation. For that purpose, a three-tiered grouping of marketing channels for livelihood development is proposed.

- by Derek Eaton
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- International Marketing, Vietnam, Food Security, Value Creation

Green gram (Vigna radiata) is commonly known as Moong an important pulse crop in India and more than 70 per cent of world’s green gram production comes from India. In Nagapattinam, farmers sow the moong after harvesting of rice crop during summer. The present study was conducted during summer of the year 2017 in three villages of Nagapattinam district to assess the suitable variety of green gram. Five farmers’ field were randomly selected and sown two high yielding improved varieties of green gram namely CO 8 and LGG 460 with five replications with one check variety already grown by the farmers. The data like average plant height, number of branches, pods/plant, grain/pod, disease incidence (%), Synchronization, 100 seed weight and pod yield (q/ha) were recorded during investigation. Among all the varieties assessed, variety CO 8 proved to be the best with highest number of pods/plant (31.2) and minimum incidence of yellow mosaic disease of 4.2 per cent resulting in the highest yield of 7.35 q/ha followed by LGG 460 with disease incidence of 5.6 per cent , 28.3 pods/plant and yield of 6.95q/ ha. Hence, it was inferred that CO 8 variety of green gram proved better followed by LGG 460.

- by Manoj Sharma
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- Crop Production, Pulses and Human health

In order to improve the crop productivity, quality of germplasm and minimise infection in different cultivars of gladiolus, its proper diagnosis and control is essential. In addition, diagnosis also helps in exporting planting material to countries wherein strict quarantine conditions have been imposed. During the last two decades much advance has been made in diagnostics for the detection of viral diseases, but incidence of viral infection is increasing. In plants, emphasis has always been given to the diagnosis of viral infection in different parts of plants, particularly in the propagating material as it indirectly helps in the control of the infection. As well as Immuno-diagnostics, molecular biology has also provided techniques like the use of DNA/RNA probes, the polymerase chain reaction, etc. to detect the viruses. These techniques have shown great potential as far as specificity and sensitivity are concerned.

- by Raja Ram
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- Molecular Biology, Molecular Diagnostics, Polymerase Chain Reaction, Crop Production

Teasel gourd (Momordica dioica) is a popular vegetable of Bangladesh usually grown in the summer season. Normally these gourds are cultivated through the root tubers, this is why variation in the cultivated teasel gourd is very limited. And for this reason, farmers usually does not get satisfactory yield by growing these low yielding local varieties of teasel gourd. Therefore, using suitable techniques new high yielding lines of teasel gourd with good fruit quality have been developed at BRAC Agricultural Research & Development Centre (BARDC), Bangladesh. These Improved lines are being maintained at BARDC and root tubers of these lines will be distributed to the farmers for home gardening purpose and commercial cultivation as well.

- by Sitesh Biswas
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- Botany, Agronomy, Food and Nutrition, Agriculture

A field experiment was conducted during seasons (2011/2012) in semi-arid zone at North Kordofan, Sudan to evaluate local sorghum (Sorghum bicolor L. Moench) genotypes for early flowering and yielding. 19 early flowered and high yielding ability genotypes were selected from the previous experiment. Randomized complete block design (RCBD) with four replications was used. Selection was done visually based on early flowering and bigger panicle size plants. Morphological, yield and yield component traits were estimated. Statistical analyses revealed significant differences among all the studied traits. Duncan Multiple Range Test organized and ranked the significances among the trait means. Results of the experiment disclosed that the highest amount of grain yield per area produced by the following genotypes: Tagat 4 (2.3), Tagat 7B (1.9), Tagat 10 (2.2), Tagat 14 (2.7) and Tagat 19 (1.9 ton h-1).

- by Ahmed M. El Naim
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- Plant Ecology, Crop Physiology, Crop Science, Crop Production

In this review paper an overview of the nitrogen (N) and phosphorus (P) cycles in agricultural systems is presented. The information summarized provides general information on the important processes involved as they relate to losses from agricultural systems. Such background information is a prerequisite for designing management strategies to achieve a sustainable balance between reducing the environmental impact of N losses and protecting farmers' profitability. In field vegetable production most N is lost via nitrate leaching because often large amounts of nitrogen remain in the soil after harvest of the crop. This N includes residual soil mineral N and N present in crop residues. Quantitative data are presented on residual soil mineral N, N present in crop residues and nitrate leaching in field vegetable production systems. To combat too high nitrate leaching from agricultural soils the European Commission has issued the Nitrate Directive. Information on this Directive and on how the Dutch government imposed legislation to meet the demands of the Nitrate Directive is given. The project "Farming with a future" is also presented. This new project has been set up in The Netherlands to develop and test environmentally and economically sustainable field crop production systems. As an example of the first results of the project, N balances of two systems of leek production are shown.

- by Hans Langeveld
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- Phosphorus, European Commission, Legislation, Crop Production
- by Rex Omonode
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- Earth Sciences, Soil, Carbon, Agriculture

Soil microbial biomass plays important roles in nutrient cycling, plant-pathogen suppression, decomposition of residues and degradation of pollutants; therefore, it is often regarded as a good indicator of soil quality. We reviewed more than a hundred studies in which microbial biomass-C (MB-C), microbial quotient (MB-C/TSOC, total soil organic carbon) and metabolic quotient (qCO 2 ) were evaluated with the objective of understanding MB-C responses to various soil-management practices in Brazilian ecosystems. These practices included tillage systems, crop rotations, pastures, organic farming, inputs of industrial residues and urban sewage sludge, applications of agrochemicals and burning. With a metaanalysis of 233 data points, we confirmed the benefits of no-tillage in preserving MB-C and reducing qCO 2 in comparison to conventional tillage. A large number of studies described increases in MB-C and MB-C/TSOC due to permanent organic farming, also benefits from crop rotations particularly with several species involved, whereas application of agrochemicals and burning severely disturbed soil microbial communities. The MB-C decreased in overgrazed pastures, but increased in pastures rotated with wellmanaged crops. Responses of MB-C, MB-C/TSOC and qCO 2 to amendment with organic industrial residues varied with residue type, dose applied and soil texture. In conclusion, MB-C and related parameters were, indeed, useful indicators of soil quality in various Brazilian ecosystems. However, direct relationships between MB-C and nutrient-cycling dynamics, microbial diversity and functionality are still unclear. Further studies are needed to develop strategies to maximize beneficial effects of microbial communities on soil fertility and crop productivity.

- by Odair Alberton
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- Microbial diversity, Biological Sciences, Organic Farming, Environmental Sciences
- by Eileen B Nchanji
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- Business, Supply Chain, Food Security, Livestock

Since 1997, the agricultural leases on Native land, issued under the 1976 Agricultural and Landlord Tenants Act (ALTA), began to expire. The sugar industry is the main commodity export earner for Fiji, directly contributing about 22% of the national GDP and supporting over 25% of the country's active labor force. Fiji exports 80% of its sugar production, earning on average of $250-300 million in foreign exchange annually. Several options have been suggested, including: non-renewal of leases, with the land reverting to Fijian owners; renewal of ALTA but with land rents pegged to the gross value of production instead of the unimproved capital value; sharecropping and contract wage arrangements; and abolishment of lease arrangement under ALTA with leases to be issued under an institutional arrangement guided by the Native Lands Trust Act (NLTA). The land tenure system adopted will have a significant impact not only on the efficiency of the sugar cane sector but also on Fiji's...

- by Hazel Lim
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- Land tenure, Sugar cane, Resource use, Risk sharing

Multi Attribute Utility Theory (MAUT) is employed to rank the irrigation subsystems of Mahi Bajaj Sagar Project, Rajasthan, India. Seven performance evaluation criteria, namely, land development works, timely supply of inputs, conjunctive use of water resources, participation of farmers, economic impact, crop productivity and environmental conservation are employed. Kohonen Artificial Neural Networks (KANN) is employed to classify the irrigation subsystems that can be utilized for further ranking by MAUT. Spearman rank correlation technique is employed to compute correlation coefficient values between the obtained ranking pattern. Sensitivity analysis studies are also made to check the robustness in ranking. The proposed methodology can be applied for similar situations.

- by Vasan Arunachalam
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- Decision Making, Methodology, Irrigation, Theory
- by Roberta Gerpacio
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- Maize, Research and Development, Crop Production, Research Priorities

This study shows the changing trend of the significant climatic variable with crop productivity (1970-2018). Sylhet district was selected as a study area. Mann-Kendall and Sen's Slope methods have been used for the trend analysis. A decrease of Aus yield at-1100.75 M. tons per year and an increase of Aman and Boro yield at a rate of 11028.56 M. tons and 22691.33 M. tons per year. No trend was shown for Wheat yield over time. An increasing trend of maximum and minimum temperature in the four-crop growing season (Aus, Aman, Boro, and Wheat) was 0.05 °C, 0.04 °C, 0.04 °C, 0.04 °C, and 0.016 °C, 0.02 °C, 0.04 °C, 0.04 °C per year respectively. Rainfall decreased to-0.04 mm,-0.03 mm, and-0.004 mm per year in Aus, Aman, and Wheat season while increasing slightly at 0.001 mm per year in Boro season. Relative humidity decreased to-0.004% and-0.03% per year in Aus and Aman season while increasing at 0.03% and 0.06% per in Boro and Wheat season. Cloud cover showed an increasing trend while wind speed provides decreasing trend in all four-crop growing seasons. The river water level also showed a decreasing trend. Finally, the changing pattern of climatic factors was profoundly fluctuating and not favorable for better crop production. Agriculture in Bangladesh is under pressure both from growing requests for food and from issues of farming area and water resources depletion. The chance of global climate change makes the issue particularly earnest.

- by Multidisciplines Publications
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- Climate Change, Crop Production, Trend Analysis, Mann-Kendall Test
- by Brad Marden and +1
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- Genetics, Oceanography, Crop Production, Population Size
- by Thomas Jayne
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- Food Policy, Uganda, Kenya, Food Security

The objective of this study was to investigate the patterns of energy use and their relationship with crop production on farms in the Dera Ismail Khan (D.I. Khan) District of the North West Frontier Province, Pakistan. A year-long survey of daily inputs of energy to more than 600 crop plots of 26 farms in seven villages was carried out. These represented both rainfed and irrigated farms operated by bullocks and tractors. Irrigation was provided by either canal or tubewells. Data on energy inputs were recorded for crop-production operations through biweekly visits to the selected farms, for human labor, bullocks, electric motors, diesel engines and tractors. Applications of fertilizers and chemicals and the results of yields were recorded. On a per hectare basis, the use of tractors reduces the use of both human labor and bullocks on farms and increases the total energy consumption. Due to timely land preparation, yields of most of the crops were higher on tractor-operated farms than on bullock-operated farms. On rainfed farms, energy consumption was the lowest due to lack of a permanent source of irrigation. Floods destroyed the crops on certain plots, and therefore subsequent operations like harvesting were not performed. Canal-irrigated farms had higher cropping intensities and used more energy than rainfed farms. Per hectare consumption of energy was highest on tubewell-irrigated farms due to the high consumption of electrical or diesel energy for pumping.

- by Gajendra Singh
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- Mechanical Engineering, Energy, Energy Consumption, Electric Motor

Use of high yielding varieties, increased use of fertilizers and chemicals and mechanized farming of the wheat crop result in high energy use. An energy scenario of wheat production in Punjab was constructed to establish optimum energy input levels and to know the sensitivity of a particular energy input level on productivity for five agro-climatic zones. The sensitivity of a particular energy input on production was assessed using the marginal physical productivity technique and partial regression coefficients. The linear programming technique based on the concept of one-to-one functions was used to optimize the various energy input uses. The study on sensitivity of energy inputs on productivity of wheat revealed that an additional 1 MJ of energy through fertilizers in zone 1, Diesel in zone 3 and chemicals in zone 4 would result in increase in the yield of wheat by 0.118, 0.219 and 0.610 kg, respectively. Statistically, a constant return to scale prevailed for wheat production in all the zones except zone 1, being rain fed. Wide variations in the efficiency rating of input use were observed in zones 1, 2 and 5. Using existing energy inputs, the yield of wheat can be increased by 22.3% in zone 1, 20.8% in zone 2, 6.1% in zone 3, 4.2% in zone 4 and 10.6% in zone 5. On average, the existing level of yield of wheat could be obtained while reducing the energy inputs use by 22.3%, 20.8%, 9.8%, 7.1% and 15.9% in zones 1, 2, 3, 4 and 5, respectively, over the actual energy use.

In this paper, weed flora associated with small-scale farming in the semi-arid Tehuacán-Cuicatlán Biosphere Reserve (Mexico) was investigated. The objectives were to describe weed floristic diversity, local uses, indigenous knowledge and farmers' management as well as weed distribution in four different crop production systems along a gradient of agricultural management intensity. In total, 161 weed species belonging to 40 families and 103 genera were found, including three endemic species of the region. Approximately, 91.9% of all weed species had one or more uses, fodder being the most important one, followed by medicinal, edible and ornamental uses. The experience and knowledge of local farmers and the biodiversity of useful weed resources associated with a large variety of local crop production systems, indicated how small-scale tropical agriculture in a developing country may be compatible with in situ conservation of useful non-crop resources. #

- by Rony Swennen and +2
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- Indigenous Knowledge, Environmental Sciences, Developing Country, Weed Management

Among the various abiotic stresses limiting the crop productivity, salinity stress is a major problem, which needs to be addressed and answered urgently. Since members of Brassicaceae are important contributor to total oilseed production, there is an immediate need being felt to raise Brassica plants which would be more suitable for saline and dry lands in years to come. One of the suggested way to develop salinity tolerant Brassica plants is to make use of the broad gene pool available within the family. Efforts of breeders have been successful in such endeavors to a large extent and several salinity tolerant Brassica genotypes have been developed within India and elsewhere. On the other hand, transgenic technology will undoubtedly continue to aid the search for the cellular mechanisms that confer tolerance, but the complexity of the trait is likely to mean that the road to engineer such tolerance into sensitive species will not be easy. However, with increasing number of reports available for suitable genetic transformation for various Brassica genotypes, there is a hope that salinity tolerance can be improved in this important crop plant. In this direction, the complete genome sequence of related wild plants such as Arabidopsis or crop plants such as rice can also serve as a platform for identification of "candidate genes". Recently, complete genome sequencing of the Brassica genomes has also been initiated with the view that availability of such useful information can pave way towards raising Brassica with improved tolerance towards these stresses. In the present paper, we discuss the success obtained so far; in raising brassica genotypes with improved salinity tolerance employing both plant breeding and/or genetic engineering tools.

- by Ram Purty
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- Bioinformatics, Life Sciences, Plant Breeding, Abiotic Stress

Transpiration-use efficiency, the ratio of biomass (Y) produced per unit of water transpired (T) by a crop, depends on crop characteristics and on the environment in which crops develop. Transpiration-use efficiency has been described as Y/T=kc/Da, where kc is a crop dependent constant and Da is the daytime air vapor pressure deficit. Our objectives were to determine Y/T and kc

- by Armen Kemanian and +1
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- Earth Sciences, Biophysics, Biomass, Ecophysiology

Legume-based green manures are important nitrogen sources in organic crop production. Direct incorporation of a green manure crop before sowing or planting of the subsequent cash crops is the most common practice. However, growing green manure crops on fields suitable for cash crop production might be economically suboptimal for the producer and it is difficult to synchronize nutrient release from the green manure with crop demand. Therefore, in this study direct incorporation of green manure was compared with other ways of using green manure where the green manure crop can be grown on fields a p p l i e d s o i l e c o l o g y 3 6 (2 0 0 7

- by Sara Elfstrand
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- Agronomy, Ecology, Biological Sciences, Phosphorus

Prehistoric water management in the northern US Southwest was integral to successful subsistence. On the Mesa Verde cuesta in southwestern Colorado, several types of water management features have been identified in the archaeological record, but research into these features has typically focused on the efficacy of reservoirs—a large-scale, labor-intensive, and community-oriented means of collecting and storing water. This focus on large-scale water management features has largely ignored the productive potential of small-scale and low-cost strategies for water management executed by individual households. There is considerable evidence, for example, that extensive check dam networks were constructed and used on the Mesa Verde cuesta, but their actual utility as a small-scale risk-aversion strategy to resource stress has not systematically been explored. This paper identifies all ephemeral drainages on the Mesa Verde cuesta where check dam construction was possible, then applies a maize growing niche model to estimate total yields from check dam farming plots for each year from AD 890–1285. A demographic reconstruction is then used to estimate the percentage of the total cuesta population that could have been supported using only check dam maize yields through time. Results suggest that check dam farming could have supplied a reliable source of surplus annual maize sufficient for household storage needs even during the most populous time periods across the cuesta landscape.

In monocarpic species, during the reproductive stage the growing grains represent a strong sink for nitrogen (N) and trigger N remobilization from the vegetative organs, which decreases canopy photosynthesis and accelerates leaf senescence. The spatiotemporal distribution of N in a reproductive canopy has not been described in detail. Here, we investigated the role of the local light environment on the spatiotemporal distribution of leaf lamina N mass per unit leaf area (SLN) during grain filling of field-grown wheat (Triticum aestivum). In addition, in order to provide some insight into the coordination of N depletion between the different vegetative organs, N dynamics were studied for individual leaf laminae, leaf sheaths, internodes, and chaff of the top fertile culms. At the canopy scale, SLN distribution paralleled the light gradient below the flag leaf collar until almost the end of grain filling. On the contrary, the significant light gradient along the flag leaf lamina was not associated with a SLN gradient. Within the top fertile culms, the time course of total (alive 1 necrotic tissues) N concentration of the different laminae and sheaths displayed a similar pattern. Another common pattern was observed for internodes and chaff. During the period of no root N uptake, N depletion of individual laminae and sheaths followed a first-order kinetics independent of leaf age, genotype, or N nutrition. The results presented here show that during grain filling, N dynamics are integrated at the culm scale and strongly depend on the local light conditions determined by the canopy structure.

- by Jessica Bertheloot and +1
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- Kinetics, Biological Sciences, Triticum Aestivum, Plant Physiology

Barind Tract of Bangladesh is one of the driest parts of the region where surface water supplies are limited. Large parts of this tract used to be fallow land because there were no major irrigation facilities until mid 1980s. A detailed hydro geological and groundwater survey of Bangladesh was implemented by UNDP in February 1978; Barind was described as follows, “the zone lie on the western Rajshahi known as Barind Tract. Thick clay deposits have been proven by test drilling which indicates that the main aquifer does not exist in the upper 300 m. Therefore groundwater potential is limited to development from relatively thin, fine grained sand zones that appear within the clay sequence. The aquifer is capable of supporting only small domestic needs”. The above mentioned theoretical study result of UNDP is surpassed by the innovation of “INVERTED WELL”. This was the outcome of the actual field trials to meet the local need and match available aquifer conditions that was not suitable ...

- by Asaduz Zaman
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- Geography, Irrigation, Groundwater, Crop Production

As part of a major effort to address soil fertility decline in West Africa, a project on Balanced Nutrient Management Systems (BNMS) has since 2000 been implemented in the northern Guinea savanna (NGS) of Nigeria. The project has tested and promoted two major technology packages, including a combined application of inorganic fertilizer and manure (BNMS-manure) and a soybean/maize rotation practice referred to as BNMSrotation. This study employed Tobit model to examine factors that influence the adoption and intensity of utilization of BNMS technologies in the NGS of Nigeria. Results showed that less than 10% of the sample households adopted at least one of the two components of the technology package by the end of 2002. However, by 2005 the adoption of BNMS-rotation had reached 40% while that of BNMS-manure had reached 48%. A number of factors such as access to credit, farmers' perception of the state of land degradation, and assets ownership were found to be significant in determining farmers' adoption decisions on BNMS-manure while offfarm income was found to be significant in determining farmers' adoption decisions on BNMS-rotation. Extension services and farmer-to-farmer technology diffusion channels were the major means of transfer of BNMS technologies.

- by Rashid Hassan
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- Human Geography, Economics, Socioeconomics, Technology

This paper discusses archaeobotanical remains of naked barley recovered from the Okhotsk cultural layers of the Hamanaka 2 archaeological site on Rebun Island, northern Japan. Calibrated ages (68% confidence interval) of the directly dated barley remains suggest that the crop was used at the site ca. 440-890 cal yr AD. Together with the finds from the Oumu site (north-eastern Hokkaido Island), the recovered seed assemblage marks the oldest well-documented evidence for the use of barley in the Hokkaido Region. The archaeobotanical data together with the results of a detailed pollen analysis of contemporaneous sediment layers from the bottom of nearby Lake Kushu point to low-level food production, including cultivation of barley and possible management of wild plants that complemented a wide range of foods derived from hunting, fishing, and gathering. This qualifies the people of the Okhotsk culture as one element of the long-term and spatially broader Holocene hunter-gatherer cultura...

- by Pavel Tarasov
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- Ancient History, Japanese Studies, Archaeology, Ethnobotany