Support Crop Production Research Articles

Managing pressmud cake for nitrogen and phosphorus nutrition of crops in a rice-wheat rotation

Rice-wheat is a nutrient-exhaustive cropping system that requires heavy inputs of fertilizers to obtain high yields. Application of organic materials to agricultural land has been viewed as an excellent way to recycle nutrients and organic matter that can support crop production and maintain or improve soil quality. Over the years, Asian farmers have used several types of organic materials. One of these is pressmud cake (PMC). PMC is produced annually from India’s sugar industry. PMC is an important byproduct when sugarcane is converted into crystalline sugar using two main processes: carbonation and sulphitation. Carbonation PMC contains high amounts of CaCO3 and is therefore not recommended for alkaline soils. PMC produced from sugar factories using sulphitation contains about 2% N and 1% P, in addition to several other plant nutrients (2.5 g Fe kg –1 , 1.5 g Mn kg –1 , 0.27 g Zn kg –1 , and 0.13 g Cu kg –1 ) (Kumar and Mishra 1991). This valuable organic material has great potential as a source of nutrients for the rice-wheat system in the Indo-Gangetic Plains. No precise information is available on the availability of N and P from the PMC in the rice-wheat rotation. Similarly, there is a dearth of agronomic strategies for the efficient use of PMC in the ricewheat system.

Selective flowers to enhance biological control of cabbage pests by parasitoids

Habitat management is an important element in sustainable agriculture and can be used to maximize a range of ecosystem services that support crop production. An important example of such ecosystem services is biological control of pests which can be enhanced by providing arthropod natural enemies with suitable floral resources. The potential risk of this approach, however, is that flowering plants may enhance the fitness of the targeted pests as well. We conducted experiments to identify selective plant species that would improve the longevity and parasitization rate of the parasitoid wasp Microplitis mediator without benefiting its host pest, the cabbage moth Mamestra brassicae. Effects on longevity were also assessed for Diadegma fenestrale, a generalist parasitoid wasp attacking lepidopteran pests. Additionally, we compared the effects of floral and extrafloral nectar, the latter being formed in some plant species and can significantly prolong the duration of nectar availability for natural enemies. Longevity of M. mediator and D. fenestrale as well as parasitization rates of M. mediator were significantly increased by the presence of Fagopyrum esculentum (floral nectar), Centaurea cyanus (floral and extrafloral nectar) and non-flowering Vicia sativa (extrafloral nectar). M. mediator parasitized 202.3±29.7 M. brassicae larvae during its lifetime when presented F. esculentum, compared to 14.4±3.4 larvae in the absence of floral resources. Extrafloral nectar of C. cyanus and V. sativa was as suitable for M. mediator as floral nectar and significantly increased longevity and parasitization rates. Longevity and fecundity of M. brassicae were not supported by the plant species tested. These results stress the importance of plant screening to achieve plant selectivity and to maximize biological control. F. esculentum, C. cyanus and V. sativa are recommended as selective plant species to enhance parasitoids of M. brassicae.

Geosensors to Support Crop Production: Current Applications and User Requirements

Sensor technology, which benefits from high temporal measuring resolution, real-time data transfer and high spatial resolution of sensor data that shows in-field variations, has the potential to provide added value for crop production. The present paper explores how sensors and sensor networks have been utilised in the crop production process and what their added-value and the main bottlenecks are from the perspective of users. The focus is on sensor based applications and on requirements that users pose for them. Literature and two use cases were reviewed and applications were classified according to the crop production process: sensing of growth conditions, fertilising, irrigation, plant protection, harvesting and fleet control. The potential of sensor technology was widely acknowledged along the crop production chain. Users of the sensors require easy-to-use and reliable applications that are actionable in crop production at reasonable costs. The challenges are to develop sensor technology, data interoperability and management tools as well as data and measurement services in a way that requirements can be met, and potential benefits and added value can be realized in the farms in terms of higher yields, improved quality of yields, decreased input costs and production risks, and less work time and load.

Bio-Based and Biodegradable Plastics for Use in Crop Production

The production and management of crops uses plastics for many applications (e.g., low tunnels, high tunnels, greenhouses, mulching, silage bags, hay bales, pheromone traps, coatings of fertilizers or pesticides or hormones or seeds, and nursery pots and containers for growing transplants). All these applications have led some authors to adopt the term "plasticulture" when discussing the use of plastic materials in agriculture and related industries. Unfortunately, the sustainability of this use of plastics is low, and renewability and degradability have become key words in the debate over sustainable production and utilization of plastic. Recently, researchers and the plastics industry have made strong efforts (i) to identify new biopolymers and natural additives from renewable sources that can be used in plastics production and (ii) to enhance the degradability (biological or physical) of the new ecologically sustainable materials. In the present review, we describe the main research results, current applications, patents that have been applied for in the last two decades, and future perspectives on sustainable use of plastics to support crop production. The article presents some promising patents on bio-based and biodegradable plastics for use in crop production.

Short- and long-term phosphorus availability in four soil orders under indigenous vegetation in Turkey

Soil phosphorus (P) fractions can be used as indicators for short- and long-term P availability. The labile organic and inorganic P concentrations are critical sources of P in agroecosystems, representing an active reservoir (source and sink) of P. The less available P pools (other than residual P) may be better measures of potentially plant available P, since these pools represent the soil P reservoir that can re-supply labile pools over time. Little information exists on P pools in soil orders under indigenous vegetation in semi-arid climates in Turkey. Our objective was to assess short- and long-term plant availability of P over depth in the soil profile using chemical P fractionation. Soil samples were collected of different horizons in the profile from each of four major soil orders: Mollisol, Entisol, Inceptisol, and Aridisol. Samples were analysed using sequential fractionation to obtain seven P pools. In order of decreasing plant availability the seven pools are: resin extracted inorganic P (resin-Pi), inorganic and organic P extracted by sodium bicarbonate (NaHCO3-Pi and NaHCO3-Po), inorganic and organic P extracted by sodium hydroxide (NaOH-Pi and NaOH-Po), sulphuric acid extracted inorganic P (H2SO4-Pi), and P measured by a sulphuric/peroxide digestion (residual-P). Topsoil contained greater amounts than deeper layers for all P fractions except residual-P. Total P levels in Aridisol were considerably higher than in the Mollisol and Inceptisol and lowest in the Entisol. The Mollisol had the highest concentrations of labile inorganic P (sum of resin-P + NaHCO3-Pi). For the surface horizon, labile organic and inorganic P concentrations combined (sum of resin-Pi, NaHCO3-Pi and NaHCO3-Po) were highest in the Mollisol, followed by the Inceptisol and Aridisol with similar levels, and the Entisol with the lowest amount of labile P. Independent of soil order, higher concentrations of NaOH-Po and NaHCO3-Po occurred in the topsoil consistent with greater organic matter levels in the surface horizons. The largest pools of NaOH-Pi and H2SO4-Pi were found in the rooting zones of the Aridisol, followed by the Inceptisol, Mollisol and Entisol. Residual-P amounted to 19–26% of total P in the Mollisol, 32–51% of total P in Aridisol, 30–34% in the Inceptisol and 39–54% in the Entsiol with a higher percentage in the deepest horizons for each of the soil orders. Our results suggest that the readily plant available soil P pools of Mollisol are sufficiently large to support crop production. On the other hand, in the Aridisol, Inceptisol and Entisol the labile P pools are small. In the Aridisol, re-supply from more stable P fractions (NaOH and H2SO4-Pi) might contribute to P availability over time. However, in the Inceptisol and Entisol, re-supply of the labile P fraction from the more stable pools will not be sufficient given small pool sizes, and so regular P applications will be needed to sustain crop production for these soil orders.

Sweet Corn Production by Using Poultry Manure

Alternative to the use of synthetic nitrogen fertilizers can be the utilization of a natural organic source of on-farm animal manure nutrients for the growth, development and production of agricultural crops. The main objective of this research was to compost the poultry manure with organic amendments and utilize for sweet corn production. The composition of composted and uncomposted poultry manure was compared and field experiments were conducted during 2002 and 2004 at Randolph farm of Virginia State Univ. located near Petersburg, Virginia. The field experiments included seven treatments: control with un-composted manure, four treatments with manure (composted with wheat straw turned weekly, composted with wheat straw turned bi-weekly, composted with clover hay turned weekly, and composted with clover hay turned bi-weekly), recommended rate of N fertilizer, and a control without any treatment. Results indicated that composting of poultry manure with an organic amendment such as wheat straw or clover hay helps poultry manure's transformation into a usable fertilizer material for supporting crop production. However, use of clover hay was observed to be desirable than wheat straw for sweet corn production. Addition of clover hay resulted in significantly increased ear fresh and dry weight and also resulted in taller plants. The affects of biweekly vs. weekly turning compost on performance of sweet corn were not significant.

The root–microbe–soil interface: new tools for sustainable plant production

The root–microbe–soil interface: new tools for sustainable plant production

Plant nutrient contents of cattle manures from small-scale farms and experimental stations in the Ethiopian highlands

In most small-scale farms in sub-Saharan Africa, net negative balances of nutrients result when nutrients are removed from the farm by harvested crops, because farmers cannot afford inorganic fertilizers. A key resource that could be useful in reversing this trend is manure from livestock. The N, P, K, Ca, Mg, Fe, Mn, Cu and Zn contents of manures collected from six experimental stations and twenty small-scale farms in the Ethiopian highlands were analysed. The manures contained, on average, 21.3 g K, 18.3 g N, 16.4 g Ca, 5.6 g Mg, 4.5 g P, 10776 mg Fe, 777 mg Mn, 92 mg Zn and 24 mg Cu per kg. Manures from experimental stations contained significantly more N, P, K, Mg, Cu and Zn than the manures from smallholder farms, probably due to differences in feed availability and quality. Fresh manures and stored (dry) manures were not significantly different in nutrient concentrations although stored manures had slightly higher nutrient concentrations, probably as a concentration effect after loss of carbon. Manures collected from farms in Deneba area had significantly greater contents of P, K, Mg, and Cu than manures collected in Ginchi area, but, due to scarcity of fuel wood, farmers in Deneba use manures for fuel for domestic cooking and heating instead of applying it to the soil. Afforestation programmes, or other programmes that would ease the energy problem for domestic use, may be necessary if manures are to be applied to soils. Whether the amount of manure in the livestock-dense Ethiopian highlands is sufficient to support crop production is unknown. Research in other parts of Africa indicates that, although adequate manure may be applied to some fields, insufficient manure is available to support crop production at a wider scale.

Soil in the agricultural area of Biosphere 2 (1991–1993)

The agricultural area (intensive agriculture biome) of Biosphere 2 was started with a meter of alkaline soil with high organic content in 1990 and used to support eight persons during closure 1991–1993. Wastes were recycled to maintain fertility. Soils sampled at the end were analyzed for major and minor inorganic constituents and organic matter. C/N ratio was high (13:1 to 17:1). Organic matter decreased 0.2 to 1.4% per year. With exception of high salinity developing in one plot and denitrification in the rice paddy, the soils at the end were functional in supporting crop production.

Cutting management ofCalliandra calothyrsus in the wet season to maximize dry season fodder production in the central highlands of Burundi

Calliandra calothyrsus was cut back at monthly intervals during the rainy season between January and May to determine which period of cutting gives the highest quantity and quality of dry matter in August, the peak of the dry season, when a lack of fodder is most acute. In both 1992 and 1993, the highest quantity of dry season production was obtained from the plots that were harvested in February, six months before the driest month. Crude protein content of the dry season fodder was not significantly influenced by the time of harvest in the rainy season. How the fodder produced in the dry season is to be used to satisfy the digestible protein needs of 3.5 goats for a 90-day period in the highlands of Burundi and how the leafy biomass harvested in the rainy season is to be used to support crop production are discussed.

New Technologies and Approaches for Weed Management in Sustainable Agriculture Systems

Weed science has a long history of solving weed management problems for farmers. Over the last four decades most of the solutions to weed problems have been based on herbicide technology. Thus, most crop production systems in the United States rely heavily on herbicides as the primary method of weed management. During the last decade environmentalists, farmers, agricultural scientists, policy makers, and the general public have begun to question the long-term sustainability of conventional farming systems. The sustainability of these systems is being questioned because of environmental, social, and economic concerns caused by global competition, cost of production, soil erosion, water pollution, and concern over the quality of rural life. Weeds are the major deterrent to the development of more sustainable agriculture systems. Since weeds dictate most of the crop production practices (e.g., tillage, herbicides, cultivation, row spacing) weed scientists must become the leaders of collaborative integrated approaches to agriculture systems research. New crop production systems must be developed that are less destructive to the environment, are profitable, conserve energy, and support rural community development. The goal is to facilitate the development of ecologically based alternative methods of weed management that will support crop production systems that require less tillage and herbicide inputs. To accomplish this goal, research efforts must be radically expanded in weed/crop ecology and in the development of ecologically based technologies for weed management.