• Authors:
    • Zhang, Y. Q.
    • Yang, .L W.
  • Source: Scientia Agricultura Sinica
  • Volume: 44
  • Issue: 11
  • Year: 2011
  • Summary: Objective: The study was to explore the geometric characteristics, spatial and temporal distributive patterns of root systems of spring wheat, millet, grain sorghum, and broomcorn millet. Method: Experimental methods employed were pot culture, soil column culture, chain link mesh box cultivation and field investigation. Result: Differences in root system characteristic patterns of the four cereal crops: Number of seminal root and secondary root was different, maximum striking depth of root systems was different which usually followed the order of grain sorghum > millet > spring wheat > broomcorn millet, maximum root extension was different, maximum root extension often showed an order of grain sorghum > broomcorn millet > millet > spring wheat. The basilar 1-3 node of millet, broomcorn millet and grain sorghum formed 1st round to 3rd round support root after tasselling, while spring wheat did not have support root commonly. Temporal distributive patterns of the four cereal crops in the experiment: root systems of millet, broomcorn millet and spring wheat grew downward gradually along with developing stage, root length and root weight increased persistently, the increase of root length and root weight showed slow-fast-slow patterns. The growth patterns of root weight and total root length of the four cereal crops accorded with S-type growth curve, while the increase per day for root length and root weight of grain sorghum was far larger than that of millet and broomcorn millet. Spatial distributive patterns of the four cereal crops in the experiment: in seedling stage root systems of the four cereal crops grew downward mainly; in each soil layer the absolute root amount increased gradually; root length and root dry weight mostly distributed in the soil layer of 0-40 cm depth; root systems hardly distributed in the soil layer of below 40 cm. Therefore, spatial patterns of the four cereal crops showed a clear T-shape. At jointing stage, root systems kept on growing downward, and the root amount in different soil layers increased distinctly. The spring wheat root weight enhanced notably, and spring wheat root length distribution showed 8-shape approximately. Patterns for root length and weight of the other three crops still showed a T-shape. At heading stage, the root length distributive patterns in different depth soil of millet, broomcorn millet and grain sorghum turned into 8-shape approximately, while the root length distributive patterns in different depths of soil of spring wheat showed an egg-shape. So, the root length of the four cereal crops in the experiment at late heading stage had superiority in middle and bottom soil layer. The vertical distribution of root weight of millet, broomcorn millet, grain sorghum followed the exponential equation y=A.e -bx , but different crops had different b values. The total root length distributive patterns of the four cereal crops in different soil depths at early stage followed the exponential equation y=A.e -bx , but at late stage it followed the multinomial y= ax3+ bx2+ cx+ d. Conclusion: The similarities in spatial distributive patterns of the root systems of the four cereal crops were positive, which provided a theoretical basis for root regulation for cultivation.
  • Authors:
    • Costa Crusciol, C. A.
    • Calonego, J. C.
    • Amaral Castro, G. S.
  • Source: Pesquisa Agropecuária Brasileira
  • Volume: 46
  • Issue: 12
  • Year: 2011
  • Summary: The objective of this work was to evaluate the effects of crop rotation systems and liming materials on soil physical properties. The experiment was carried out from October 2006 to July 2008, in Botucatu, SP, Brazil, in a completely randomized block design in a split-plot arrangement with eight replicates. Main plots consisted of four crop rotation systems: soybean/fallow/maize/fallow, soybean/white-oat/maize/bean, soybean/millet/maize/pigeon pea and soybean/signal grass/maize/signal grass. Subplots consisted of the control treatment, without soil correction, and of the application of 3.8 Mg ha(-1) of dolomitic lime (ECC = 90%) or 4.1 Mg ha(-1) of calcium-magnesium silicate (ECC = 80%), on the surface of a clayed Rhodic Ferralsol. Aggregate stability, soil bulk density, total porosity, macro and microporosity, soil penetration resistance and moisture content were evaluated. Superficial application of the lime materials does not reduce soil aggregation and increases macroporosity down to 0.20 m, with calcium-magnesium silicate application, and to 0.10 m, when lime is applied. Soil under fallow in off-season decreases aggregate stability and increases soil penetration resistance in upper layers. The cultivation of Congo signal grass, between summer crops, increases aggregate stability down to 0.10-m depth.
  • Authors:
    • Akram, M.
    • Sahota, A. W.
    • Anjum, M. A.
    • Ali, I.
  • Source: Journal of Animal and Plant Sciences (JAPS)
  • Volume: 21
  • Issue: 2
  • Year: 2011
  • Summary: A total of 100 samples, 50 each of layer starter and broiler starter feeds manufactured by 10 different commercial feed mills were collected to assess contamination of aflatoxin B 2 and Ochratoxin A in poultry feeds and feed ingredients in Punjab. 440 samples of different poultry feed ingredients including cereal grains and animal and vegetable protein sources were also collected from all over Punjab and were analyzed for Ochratoxin A (OA) content. The mean concentration of aflatoxin B 2 in layer and broiler starter rations was observed to range from 10.80 (2.16) to 39.20 (3.67) g Kg 1. Out of 100 feed samples tested, 40 contained higher than the maximum tolerance level of 20 gKg -1 aflatoxin B 2. Out of the 440, 19.32 percent (n=85) were contaminated with OA. The occurrence of OA was found to be higher in maize (40%), sun flower (30%), wheat (28%), corn gluten (25%) and barley (24%). OA detected in rice, sorghum, peanut meal, soybean meal, guar meal, corn gluten and rice polish was found to be 20 percent. The findings further showed that maize had maximum mean OA concentration of 112.20 (22.69) gKg -1, followed by 59.43 (22.32) gKg -1 in wheat, 50.33 (13.79) gKg -1 in sunflower meal, 49.20 (10.23) gKg -1 in peanut meal and 39.14 (15.06) gKg -1 in rice polishing. Corn gluten meal, sorghum, barley, cotton seed meal and rapeseed meal contained mean OA concentration ranging from 30 to 36 gKg -1. The OA content ranging from 10 to16.67 gKg -1 was detected in samples of wheat bran, fish meal, blood meal and meat meal. The aflatoxin B 2 and OA contamination of poultry feeds and feed ingredients having deleterious effects seems to pose a serious threat for local poultry farming sector which calls for regular testing and surveillance of poultry feeds and adoption of necessary remedial measures.
  • Authors:
    • Yawson, D. O.
    • Obiri, S.
    • Yengoh, G. T.
    • Odoi, J. O.
    • Armah, F. A.
    • Afrifa, E. K. A.
  • Source: Mitigation and Adaptation Strategies for Global Change
  • Volume: 16
  • Issue: 3
  • Year: 2011
  • Summary: Desertification, climate variability and food security are closely linked through drought, land cover changes, and climate and biological feedbacks. In Ghana, only few studies have documented these linkages. To establish this link the study provides historical and predicted climatic changes for two drought sensitive agro-ecological zones in Ghana and further determines how these changes have influenced crop production within the two zones. This objective was attained via Markov chain and Fuzzy modelling. Results from the Markov chain model point to the fact that the Guinea savanna agro-ecological zone has experienced delayed rains from 1960 to 2008 while the Sudan savanna agro-ecological zone had slightly earlier rains for the same period. Results of Fuzzy Modelling indicate that very suitable and moderately suitable croplands for millet and sorghum production are evenly distributed within the two agro-ecological zones. For Ghana to adapt to climate change and thereby achieve food security, it is important to pursue strategies such as expansion of irrigated agricultural areas, improvement of crop water productivity in rain-fed agriculture, crop improvement and specialisation, and improvement in indigenous technology. It is also important to encourage farmers in the Sudan and Guinea Savanna zones to focus on the production of cereals and legumes (e.g. sorghum, millet and soybeans) as the edaphic and climatic factors favour these crops and will give the farmers a competitive advantage. It may be necessary to consider the development of the study area as the main production and supply source of selected cereals and legumes for the entire country in order to free lands in other regions for the production of crops highly suitable for those regions on the basis of their edaphic and climatic conditions.
  • Authors:
    • Jha, N.
    • Kundu, S. S.
    • Singh, S.
    • Gupta, A.
  • Source: The Indian Journal of Animal Sciences
  • Volume: 81
  • Issue: 11
  • Year: 2011
  • Summary: Seventeen feed ingredients comprising protein sources (linseed cake-LSC, mustard seed cake-MSC, cotton seed cake-CSC, soybean cake-SBC and groundnut cake-GNC), energy sources (deoiled rice bran-DORB, maize grain-MG, barley grain-BG and wheat bran-WB), legume roughages (berseem, cowpea hay-CH, Stylosanthes hamata-SH and Acacia catechu-AC) and non-legume roughages (ammoniated wheat straw-AWS, guinea grass-GG maize fodder-MF and sorghum fodder-SF) were evaluated for carbohydrate and nitrogen fractions as well as mineral contents. In CNCP system, crude protein content of feed is partitioned into 5 fractions (A, B 1, B 2, B 3 and C) and carbohydrate into 4 fractions (A, B 1, B 2 and C) according to degradation rates. The proximate composition, cell wall constituents, carbohydrate and nitrogen fractions of different feeds vary significantly amongst the groups. The CHO, C NSC, C B1, and Cc fractions of carbohydrate were higher in energy, while C A and C B2 fraction of CHO were more in protein sources. Total CHO and C B2 fraction of carbohydrates were more in non-legume while C A, C NSC and Cc fractions were higher in legume roughages. Amongst the studied feedstuffs P A and P B fractions of protein were higher in protein sources, while P B2, P B3 and P C fractions were higher in energy sources. Legumes exhibited higher contents of P B2, while non-legume had higher P A, P B1 and P B3 fraction of protein. Concentration of macro (%) and micro minerals (ppm) of feed stuffs differed across feeds (energy and protein) and roughages (legumes and non legumes). It is concluded from the present study that feedstuffs chemical properties for carbohydrate and nitrogen fractions are unique and different. Therefore feed ingredients selection based on CNCPS evaluation will be more logical for formulating efficient diets for livestock.
  • Authors:
    • Puig, R.
    • Rius, A.
    • Riba, J.-R.
    • Esteban, B.
    • Baquero, G.
  • Source: Biomass and Bioenergy
  • Volume: 35
  • Issue: 8
  • Year: 2011
  • Summary: The use of straight vegetable oil (SVO) as biofuel has been recognized as a valid substitute of diesel fuel in the agricultural sector under specific circumstances. Its direct use reduces most of the chemical processes involved when converting it into biodiesel, thus lowering harmful emissions. This study presents the economic analysis of a self-supply farming model that uses rapeseed as its fuel base. This model addresses agricultural environmental concerns and can even minimize dependence on the fluctuating costs of diesel fuel. The use of SVO in agriculture can help reduce farmers' vulnerability to fossil fuel prices. The economic evaluation of the model proposed in this study shows clear economic benefits of introducing rapeseed to the traditional crop rotation of wheat and barley. The key factors analyzed in this model are diesel fuel price, diesel fuel grants and crop aids. The current situation in Spain favors the use of diesel fuel in agriculture rather than rapeseed SVO due to an 8% profit difference. However, results show that changes in key factors slightly affect the profit margin, calculating a difference of only 3.7% for particular factor combinations. Combined environmental-friendly agriculture supporting policies are necessary to cover this slight profit difference to promote this biofuel. (C) 2011 Elsevier Ltd. All rights reserved.
  • Authors:
    • Elfstrand, S.
    • Båth, B.
    • Wetterlind, J.
    • Stenberg, M.
    • Bergkvist, G.
  • Source: Field Crops Research
  • Volume: 120
  • Issue: 2
  • Year: 2011
  • Summary: Four two-year field trials, arranged in randomised split-plots, were carried out in southern Sweden with the aim of determining whether reduced N fertiliser dose in winter wheat production with spring under-sown clover cover crops, with or without perennial ryegrass in the seed mixture, would increase the clover biomass and hence the benefits of the cover crops in terms of the effect on the wheat crop, on a subsequent barley crop and on the risk of N leaching. Four doses of nitrogen (0, 60, 120 or 180 kg N ha(-1)) constituted the main plots and six cover crop treatments the sub-plots. The cover crop treatments were red clover (Trifolium pratense L). white clover (Trifolium repens L) and perennial ryegrass (Lolium perenne L.) in pure stands and in mixtures. The winter wheat (Triticum aestivum L.) was harvested in August and the cover crops were ploughed under in November. The risk of N leaching was assessed in November by measuring the content of mineral N in the soil profile (0-30, 30-90 cm). In the following year, the residual effects of the cover crops were investigated in spring barley (Hordeum distichon L) without additional N. Under-sowing of cover crops did not influence wheat yield, while reduced N fertiliser dose decreased yield and increased the clover content of the cover crops. When N was applied, the mixed cover crops were as effective in depleting soil mineral nitrogen as a pure ryegrass cover crop, while pure clover was less efficient. The clover content at wheat harvest as well as the amount of N incorporated with the cover crops had a positive correlation with barley yield. Spring barley in the unfertilised treatments yielded, on average, 1.9-2.4 Mg DM ha(-1) more in treatments with clover cover crops than in the treatment without cover crops. However, this positive effect decreased as the N dose to the preceding wheat crop increased, particularly when the clover was mixed with grass. (C) 2010 Elsevier B.V. All rights reserved.
  • Authors:
    • Hedtcke, J. L.
    • Stoltenberg, D. E.
    • Posner, J. L.
    • Bernstein, E. R.
  • Source: Agronomy Journal
  • Volume: 103
  • Issue: 4
  • Year: 2011
  • Summary: A major challenge that organic grain crop growers face is weed management. The use of a rye (Secale cereale L.) cover crop to facilitate no-tillage (NT) organic soybean [Glycine max (L.) Merr.] production may improve weed suppression and increase profitability. We conducted research in 2008 and 2009 to determine the effect of rye management (tilling, crimping, and mowing), soybean planting date (mid-May or early June), and soybean row width (76 or 19 cm), on soybean establishment, soil moisture, weed suppression, soybean yield, and profitability. Soybean establishment did not differ between tilled and NT treatments; and soil moisture measurements showed minimal risk of a drier soil profile in NT rye treatments. Rye mulch treatments effectively suppressed weeds, with 75% less weed biomass than in the tilled treatment by mid-July. However, by this time, NT soybean competed with rye regrowth, were deficient in Cu, and accumulated 22% as much dry matter (DM) and 28% as much N compared to the tilled treatment. Soybean row width and planting date within NT treatments impacted soybean productivity but not profitability, with few differences between mowed and crimped rye. Soybean yield was 24% less in the NT treatments than the tilled treatment, and profitability per hectare was 27% less. However, with fewer labor inputs, profitability per hour in NT rye treatments was 25% greater than in tilled soybean; in addition, predicted soil erosion was nearly 90% less. Although soybean yields were less in NT rye mulch systems, they represent economically viable alternatives for organic producers in the Upper Midwest.
  • Authors:
    • Schroeder, K. L.
    • Paulitz, T. C.
    • Schillinger, W. F.
  • Source: Plant Disease
  • Volume: 94
  • Issue: 1
  • Year: 2010
  • Summary: An irrigated cropping systems experiment was conducted for 6 years in east-central Washington State to examine agronomic and economic alternatives to continuous annual winter wheat ( Triticum aestivum) with burning and plowing, and to determine how root diseases of cereals are influenced by management practices. The continuous winter wheat treatment with burning and plowing was compared with a 3-year no-till rotation of winter wheat-spring barley ( Hordeum vulgare)-winter canola ( Brassica napus) and three straw management treatments: burning, straw removal, and leaving the straw stubble standing after harvest. Take-all disease and inoculum increased from years 1 to 4 in the continuous winter wheat treatment with burning and plowing, reducing plant growth compared to the no-till treatments with crop rotations. Inoculum of Rhizoctonia solani AG-8 was significantly lower in the tilled treatment compared to the no-till treatments. Inoculum concentration of Fusarium pseudograminearum was higher than that of F. culmorum, and in one of three years, the former was higher in treatments with standing stubble and mechanical straw removal compared to burned treatments. Residue management method had no effect on Rhizoctonia inoculum, but spring barley had more crown roots and tillers and greater height with stubble burning. This 6-year study showed that irrigated winter wheat can be produced in a no-till rotation without major disease losses and demonstrated how cropping practices influence the dynamics of soilborne cereal diseases and inoculum over time.
  • Authors:
    • Naeem, M.
    • Khan, F.
    • Ahmad, W.
  • Source: Soil and Environment
  • Volume: 29
  • Issue: 1
  • Year: 2010
  • Summary: This study was undertaken as a part of soil fertility management of eroded soils in NWFP, Pakistan. The study was started in summer 2006 and continued for four consecutive crop seasons till winter 2007, in District Swabi, NWFP, Pakistan. Soil fertility status of the experimental site was determined before the start of the experiment. The experiment was laid out in a factorial split plot design using two factors viz cropping patterns and fertilizer treatments. The cropping patterns included maize-wheat-maize rotation, maize-lentil-maize rotation and maize-wheat+lentil intercrop-maize rotation and these were kept in main plots whereas the fertilizer treatments included control, 50% NP, 100% NPK and 20 t ha -1 farmyard manure integrated with 50% N and 100% PK as mineral fertilizers which were placed in sub plots. Fertilizers were applied for four seasons continuously. At the end of winter 2007, soil samples from two depths (0-20 cm and 20-40 cm) were collected from each plot and analyzed for microbial biomass carbon (MBC) at day 3, day 6 and day 10 incubation periods, total nitrogen (TN), microbial biomass nitrogen (MBN), and mineralizable nitrogen (MN). Results showed significant improvement in organic fertility of soil with fertilizer addition and cropping patterns. Combined application of organic and inorganic fertilizers (20 t ha -1 farmyard manure integrated with 50% N and 100% PK) showed 55, 25, 18 and 61% increase in total N, MBN, MN, and MBC after 10 days incubation period over the control, respectively, in the surface soil whilst 100% NPK showed 44, 15, 6 and 45% improvement over the control treatment for the same parameters in surface soil. Data further showed 43, 23, 19 and 60% increase in the corresponding microbial parameters in combined organic and inorganic fertilizer treatment over the control treatment in sub soil whilst 100% NPK showed 39, 20, 10 and 54% increase in TN, MBN, MN and MBC over the control in sub soil. The cropping patterns having cereal-legume rotation also improved organic soil fertility and showed 27 and 13% more total N and MBC after 10 days incubation period over the cereal-cereal rotation respectively and the improvement in MBN and MN in cereal-legume rotation over cereal-cereal rotation was non significant in surface soil. In the sub-surface soil cereal-legume rotation improved TN, MBN, MN and MBC by 9, 6, 8 and 28% over the cereal-cereal rotation. It was concluded that there is sufficient potential to improve soil organic fertility in Pirsabak soil series, the restoration of which on sustained basis would require at least 50% N from the organic sources. Moreover legumes must be included in the traditional cereal-cereal cropping pattern to further improve the N input and organic fertility of these soils.