• Authors:
    • Beghin, J. C.
    • Fang, C.
  • Source: Agricultural trade and policy in China: issues, analysis and implications
  • Year: 2003
  • Summary: This chapter assesses the protection and comparative advantage of China's major agricultural crops in six regions, using a modified Policy Analysis Matrix and 1997-2000 data. The following commodities are considered: early indica rice, late indica rice, japonica rice, wheat, maize, sorghum, soyabean, rapeseed, cotton, tobacco, sugarcane, and a subset of fruits and vegetables. The results suggest that, with the exception of high quality rice, the production of grains and oilseeds tends to suffer from a lack of comparative advantage over other crops in China, such as fruit and vegetables, tobacco and cotton. Further, it is concluded that grain self-sufficiency policies reduce allocative efficiency several-fold.
  • Authors:
    • Anand, K. V.
    • Katyal, V.
    • Gangwar, B.
  • Source: Indian Journal of Agricultural Science
  • Volume: 73
  • Issue: 9
  • Year: 2003
  • Summary: An experiment was conducted in Akola, Parbhani and Rahuri, Maharashtra, India to evaluate the productivity of various cropping sequences. In Akola (1987-88 to 1997-98) representing Vidharbha zone, the cropping sequence involving upland cotton ( Gossypium hirsutum)-groundnut ( Arachis hypogaea) was the most suitable and efficient, resulting in the highest grain-equivalent yield (10 079 kg ha -1 year -1), productivity (43.82 kg day -1 ha -1 wheat grain equivalent), profitability (49 539 rupees ha -1 year -1), economic efficiency (135.7 rupees day -1 ha -1) and land use efficiency (90.0%), and good benefit:cost ratio (16.57) and stability (0.68). However, in terms of energetics, soyabean ( Glycine max)-groundnut sequence was superior. In Central Maharashtra Plateaux Zone, cotton-groundnut sequence was also identified as the most efficient based on an 8-year study at Parbhani (1990-91 to 1997-98). This sequence gave the highest yield (12 060 kg ha -1 year -1 wheat grain equivalent), productivity (50.04 kg day -1 ha -1), profitability (62 053 rupees ha -1 year -1), economic efficiency (170.0 rupees day -1 ha -1) and land use efficiency (85%), with moderate system stability (0.59). In terms of energetics, soyabean-Indian mustard ( Brassica juncea) was superior. At Rahuri, representing western Maharashtra scarcity zone, sole sugarcane recorded the highest net return (93 429 rupees ha -1 year -1), economic efficiency (255.9 rupees ha -1 day -1) and benefit:cost ratio (19.96). Sorghum ( Sorghum bicolor)-cabbage ( Brassica oleracea var. capitata)-cowpea ( Vigna unguiculata) was equally profitable for fodder, resulting in a wheat grain yield equivalent of 22 793 kg ha -1 year -1, productivity of 94.2 kg day -1 ha -1, profitability of 81 733 rupees ha -1 year -1, economic efficiency of 223.9 rupees day -1 ha -1, and carbohydrate production of 4.69 g 10 6/ha.
  • Authors:
    • Felton, W.
    • Haigh, B.
  • Source: Update of research in progress at the Tamworth Agricultural Institute 2002
  • Year: 2003
  • Summary: Crop growth rate and weed competition were studied in New South Wales, Australia during 2002 using reflectance sensors. Seeds of wheat cv. Sunstate, chickpea cv. Howzat, faba bean cv. Fiord and rape cv. Oscar were sown at 40, 70, 100 and 3 kg/ha, respectively. Two reflectance sensors mounted on a small tractor were used to collect data across each plot every two weeks (45-129 days after sowing). Wheat recorded the greatest biomass, yield and water consumption, whereas chickpea recorded the highest harvest index and lowest water consumption. The rate of crop development was greatest in wheat and lowest in chickpea. The number of days required to produce 1000 kg/ha of shoot dry matter was 92, 100, 102 and 11 days after sowing for wheat, faba bean, rape and chickpea, respectively. Reflectance measurements were also used to evaluate the potential of wheat, triticale and barley as 'mimic weeds' against wild oat [ Avena fatua] in chickpea. Reflectance estimates were made at 51, 62, 84, 100 and 120 days after sowing. The 'mimic weeds' established faster than wild oat. The density of wild oat was lower than that of the mimic weeds, although none of the weeds achieved the target density of 81 weeds/m 2. The similar linear relationships with regard to the effects of weed biomass on crop yield for wild oat and 'mimic weeds' indicated that the latter can be used in weed studies instead of the actual weed. At low densities, wheat and barley were the most competitive. Triticale and wild oat exhibited similar competitive ability.
  • Authors:
    • Crawford, M.
    • Ransom, K.
    • Hirth, J.
    • Harris, R.
    • Naji, R.
  • Source: Solutions for a better environment: Proceedings of the 11th Australian Agronomy Conference, Geelong, Victoria, Australia, 2-6 February 2003
  • Year: 2003
  • Summary: Companion cropping (also known as intercropping) of lucerne involves sowing an annual crop into an existing lucerne stand. A sample of eight farmers from north central Victoria, Australia, who currently companion crop, were interviewed to document the impact of this practice on grain production, and to determine why and how they used this approach in their farming system. All eight farmers companion cropped lucerne to produce grain for either human or livestock consumption. Wheat, barley, oat and triticale were most commonly sown into lucerne stands, with rape less frequently companion cropped. Most companion-cropped stands of lucerne were either winter-active or highly winter-active cultivars and most had densities of 10-30 plants/m 2. They were commonly 9-12 months old, although some stands up to 10 years old were successfully companion cropped. Sowing rates of the annual crop were generally greater than those used in conventional monoculture cropping, and most farmers sowed diagonally across existing lucerne rows. Most interviewed farmers adopted companion cropping because of perceived better economic returns from cropping rather than grazing their second-year stands of lucerne, which then became more persistent and productive stands for future grazing. Farmers who companion cropped into mature stands aimed to maintain year-round plant transpiration to minimize the impact of their cropping practices on local groundwater systems, through a better hydrologic balance between the rainfall and their vegetation. Decreased grain yields from companion-cropped crops were common, and were estimated to be 10 to 80% of those obtained in the absence of lucerne. The magnitude of the yield decreases appeared to be most strongly influenced by seasonal conditions. The use of herbicides for in-crop lucerne suppression was perceived to enhance grain quality by slowing lucerne growth over the late winter-spring period, thereby reducing lucerne seed and herbage contamination at harvest. As seasonal and soil water conditions critically influenced the success of herbicide applications, specialist advice was often sought.
  • Authors:
    • UK, National Institute of Agricultural Botany (NIAB)
  • Source: Pocket guide to varieties of cereals, oilseeds & pulses for autumn 2003
  • Year: 2003
  • Summary: This edition presents information on the autumn sown varieties of wheat, barley, oats, triticale, rye, durum wheat, oilseed rape, linseed, peas and beans. Individual information on each variety is given, including variety notes, yield performance, relative ranking position in different environments and a summary of the important character ratings from the Recommended Lists.
  • Authors:
    • Featherstone, A. M.
    • Langemeier, M. R.
    • Abdulkadri, A. O.
  • Source: Applied Economics
  • Volume: 35
  • Issue: 7
  • Year: 2003
  • Summary: The risk attitudes of dryland wheat, irrigated maize, and dairy producers in Kansas, USA, are examined using the nonlinear mean-standard deviation approach. Observations on farm characteristics, obtained from 1993-97, and the statewide market year average prices for wheat and maize from 1950-97, are used. Results of analyses indicated that dryland wheat and dairy producers are characterized by increasing absolute and increasing relative risk aversion while irrigated maize producers are characterized by constant absolute and increasing relative risk aversion. Both crop enterprises exhibited constant returns to scale technology while the dairy enterprise exhibited decreasing returns to scale. Gross farm income was significant and positively related to relative risk aversion.
  • Authors:
    • Bacon, R. K.
    • Gibbons, J.
    • Moldenhauer, K. A. K.
    • Windham, T. E.
    • Anders, M. M.
    • McNew, R. W.
    • Grantham, J.
    • Holzhauer, J.
  • Source: Research Series - Arkansas Agricultural Experiment Station
  • Issue: 504
  • Year: 2003
  • Summary: Rotation, tillage, and variety main effects on grain yield were all significant in 2002. Rice grain yield, over all treatment combinations, averaged 159 bu/acre, which was 22 bu/acre more than in 2001. Grain yields for the two 3-phase rotations were 180 bu/acre for the rice-corn-soybeans rotation and 177 bu/acre for the rice-corn (wheat)-soybean rotation. These yields were slightly better than the 174 bu/acre yield from the rice-soybean rotation and 165 bu/acre from the rice-corn rotation. Grain yield declined 13 bu/acre in the continuous rice treatments when compared to 2001 yields and 27 bu/acre from the 2000 yields. Plant growth was poor in all the continuous rice plots with leaf nitrogen (N) levels lower than in other rotations. Conventional tillage treatment combinations yielded 17 bu/acre more than the no-till combinations, but this difference varied between rotations. For the continuous rice rotation, the conventional-till yielded 37 bu/acre more than the no-till whereas the same difference was 14 bu/acre in the rice-soybean rotation. There was a non-significant 7 bu/acre increase in rice yield over all treatment combinations with the 'enhanced' fertility treatments when compared to the 'standard' fertility treatments. Wells yielded a non-significant 7 bu/acre better than LaGrue across all treatments. Rice grain yield from the two rotations where rice was planted after wheat averaged 144 bu/acre-significantly higher than any previous year. There was an overall yield loss of 12 bu/acre from no-till when compared to conventional tillage, a 4 bu/acre gain from increased fertility, and a 16 bu/acre gain from the variety XL-7 when compared to RU1093. Of all the treatment combinations in this comparison the no-till rice (wheat)-soybean (wheat) rotation using enhanced fertility and the variety XL-7 was the most productive with a rice yield of 181 bu/acre and a wheat yield of 77 bu/acre. Overall, irrigation-water use declined from the previous year with an average of 26 inches needed for the conventional till treatments and 24 inches for the no-till treatments. Continuous rice needed only 17 inches of irrigation while all other rotations required between 28 and 32 inches.
  • Authors:
    • Fielding, D. J.
    • Begna, S. H.
  • Source: Journal of Economic Entomology
  • Volume: 96
  • Issue: 4
  • Year: 2003
  • Summary: We characterized the type and extent of grasshopper injury to above- and below-ground plant parts for four crops, i.e. barley ( Hordeum vulgare), oats ( Avena sativa), wheat ( Triticum aestivum), and canola [turnip rape] ( Brassica campestris [ B. campestris var. oleifera]), commonly grown, or with potential to grow, in central Alaska, USA. Cages were placed on 48 pots containing plants in second to third leaf stages and stocked with 0, 2, 4, and 6 first-instar Melanoplus sanguinipes pot -1. Plants were harvested 22 days after planting. Stem growth of barley and oats was not affected except at the highest grasshopper treatment. In rape, stem biomass was reduced at the medium and high grasshopper treatments, when most of the leaves had been consumed. The highest grasshopper treatment reduced leaf area in barley and oats by ~55%, and caused a significant reduction in dry weight of leaves, stems, and roots (41-72%). Wheat and canola plants were smaller than barley and oats across all treatments and, at the highest grasshopper density, above-ground portions of wheat and canola were completely destroyed. Length and surface area of roots of barley and oats were reduced by 20-28% again at the highest grasshopper density, whereas the reduction for wheat and canola ranged from 50 to 90%. There was little or no difference among all grasshopper densities for C:N ratio in leaf and stem tissues of all crops. The results suggest that wheat and canola are more susceptible than barley and oats and that densities ≥2 pot -1 (~≥50 m -2) of even very small grasshoppers could cause significant damage in small-grain and oilseed crop production.
  • Authors:
    • Marland, G.
    • West, T. O.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 91
  • Issue: 1-3
  • Year: 2002
  • Summary: The atmospheric CO2 concentration is increasing, due primarily to fossil-fuel combustion and deforestation. Sequestering atmospheric C in agricultural soils is being advocated as a possibility to partially offset fossil-fuel emissions. Sequestering C in agriculture requires a change in management practices, i.e. efficient use of pesticides, irrigation, and farm machinery. The C emissions associated with a change in practices have not traditionally been incorporated comprehensively into C sequestration analyses. A full C cycle analysis has been completed for agricultural inputs, resulting in estimates of net C flux for three crop types across three tillage intensities. The full C cycle analysis includes estimates of energy use and C emissions for primary fuels, electricity, fertilizers, lime, pesticides, irrigation, seed production, and farm machinery. Total C emissions values were used in conjunction with C sequestration estimates to model net C flux to the atmosphere over time. Based on US average crop inputs, no-till emitted less CO2 from agricultural operations than did conventional tillage, with 137 and 168 kg C ha(-1) per year, respectively. Changing from conventional tillage to no-till is therefore estimated to both enhance C sequestration and decrease CO2 emissions. While the enhanced C sequestration will continue for a finite time, the reduction in net CO2 flux to the atmosphere, caused by the reduced fossil-fuel use, can continue indefinitely, as long as the alternative practice is continued. Estimates of net C flux, which are based on US average inputs, will vary across crop type and different climate regimes. The C coefficients calculated for agricultural inputs can be used to estimate C emissions and net C flux on a site-specific basis. Published by Elsevier Science B.V.
  • Authors:
    • Post, W. M.
    • West, T. O.
  • Source: Soil Science Society of America Journal
  • Volume: 66
  • Issue: 6
  • Year: 2002
  • Summary: Changes agricultural management can potentially increase the accumulation rate of soil organic C (SOC), thereby sequestering CO2 from the atmosphere. This study was conducted to quantify potential soil C sequestration rates for different crops in response to decreasing tillage intensity or enhancing rotation complexity, and to estimate the duration of time over which sequestration may occur. Analyses of C sequestration rates were completed using a global database of 67 long-term agricultural experiments, consisting of 276 paired treatments. Results indicate, on average, that a change from conventional tillage (CT) to no-till (NT) can sequester 57 +/- 14 g C m(-2) yr(-1), excluding wheat (Triticum aestivum L.)-fallow systems which may not result in SOC accumulation with a change from CT to NT. Enhancing rotation complexity can sequester an average 20 +/- 12 g C m(-2) yr(-1), excluding a change from continuous corn (Zea mays L.) to corn-soybean (Glycine mar L.) which may not result in a significant accumulation of SOC. Carbon sequestration rates, with a change from CT to NT, can be expected to peak in 5 to 10 yr with SOC reaching a new equilibrium in 15 to 20 yr. Following initiation of an enhancement in rotation complexity, SOC may reach a new equilibrium in approximately 40 to 60 yr. Carbon sequestration rates, estimated for a number of individual crops and crop rotations in this study, can be used in spatial modeling analyses to more accurately predict regional, national, and global C sequestration potentials.