• Authors:
    • Rydberg, T.
    • Keller, T.
    • Arvidsson, J.
    • Håkansson, I.
  • Source: Acta Agriculturae Scandinavica, Section B - Soil & Plant Science
  • Volume: 61
  • Issue: 5
  • Year: 2011
  • Summary: Rapid and uniform crop establishment is a prerequisite for efficient crop production and minimal environmental impact. Experiments were carried out in shallow plastic boxes placed directly on the ground in the field for studies of the effects of seedbed properties on emergence of various crops. This paper presents an analysis of the time required for germination and emergence under near-optimal seedbed conditions. The crops studied were barley, oats, wheat, pea, rape seed, white mustard, sugar beet, red clover and timothy. The time required for germination generally increased with size of the seeds, presumably because larger seeds needed more water to initiate germination. This applied both when comparing different crops and different seed sizes of the same crop. However, considerable differences occurred between seed lots of the same crop and there were greater differences between seed lots of the same crop than between the three small grain crops studied. Growth rate of the seedlings generally increased with seed size, presumably because of increased energy content in the seed. Consequently, the most rapid emergence was obtained from small seeds at shallow sowing and from large seeds at deep sowing. The crops studied had a minimum temperature for germination and seedling growth close to 0 degrees C. Under optimal seedbed conditions, thermal time required for 50% germination of barley was typically about 65 degrees C days over this base temperature and for seedling growth about 6 degrees C days cm(-1). From 4 cm sowing depth, about 80 degrees C days were required for emergence but with considerable variations between seed lots. For rape seed or white mustard about 40 degrees C days were required for germination and about 8 degrees C days cm(-1) for the seedling growth.
  • Authors:
    • Holm, F. A.
    • Johnson, E. N.
    • Blackshaw, R. E.
    • O'Donovan, J. T.
    • Harker, K. N.
    • Clayton, G. W.
  • Source: Weed Science
  • Volume: 59
  • Issue: 3
  • Year: 2011
  • Summary: Growing crops that exhibit a high level of competition with weeds increases opportunities to practice integrated weed management and reduce herbicide inputs. The recent development and market dominance of hybrid canola cultivars provides an opportunity to reassess the relative competitive ability of canola cultivars with small-grain cereals. Direct-seeded (no-till) experiments were conducted at five western Canada locations from 2006 to 2008 to compare the competitive ability of canola cultivars vs. small-grain cereals. The relative competitive ability of the species and cultivars was determined by assessing monocot and dicot weed biomass at different times throughout the growing season as well as oat (simulated weed) seed production. Under most conditions, but especially under warm and relatively dry environments, barley cultivars had the greatest relative competitive ability. Rye and triticale were also highly competitive species under most environmental conditions. Canada Prairie Spring Red wheat and Canada Western Red Spring wheat cultivars usually were the least competitive cereal crops, but there were exceptions in some environments. Canola hybrids were more competitive than open-pollinated canola cultivars. More importantly, under cool, low growing degree day conditions, canola hybrids were as competitive as barley, especially with dicot weeds. Under most conditions, hybrid canola growers on the Canadian Prairies are well advised to avoid the additional selection pressure inherent with a second in-crop herbicide application. Combining competitive cultivars of any species with optimal agronomic practices that facilitate crop health will enhance cropping system sustainability and allow growers to extend the life of their valuable herbicide tools.
  • Authors:
    • Shostak, Z. A.
  • Source: Russian Meteorology and Hydrology
  • Volume: 36
  • Issue: 12
  • Year: 2011
  • Summary: The methods are presented of agrometeorological forecasting of winter and spring grain crops for the district, all types of farm units, and field taking account of the regional crop forecast, weather conditions, cereal cropping technologies, and soil cultivation level. The additional yields of winter and spring wheat and spring barley and oat are developed depending on the soil cultivation level, summertime soil moistening, and doses of mineral fertilizers. The method tested on the basis of independent data demonstrated that the accuracy of such forecasts is 83-99% for the fields with intensive cultivation technology and 80% for the farm units.
  • Authors:
    • Schoenau, G.
    • Tabil, L.
    • Adapa, P.
  • Source: Biomass and Bioenergy
  • Volume: 35
  • Issue: 1
  • Year: 2011
  • Summary: Grinding experiments were conducted on non-treated and steam exploded barley, canola, oat and wheat straw using a forage chopper and a hammer mill (screen sizes of 30, 6.4, 3.2 and 1.6 mm) to determine specific energy requirements, and geometric mean particle size and distribution of ground material. The bulk density of non-treated biomass was significantly higher than bulk density of steam exploded agricultural biomass. For non-treated agricultural straw, the particle density of canola and oat straw significantly increased with a decrease in hammer mill screen size from 30 to 1.6 mm. The particle density of steam exploded barley and oat straw was significantly higher than non-treated straw, except for barley at 6.4 mm hammer mill screen size. The particle density of steam exploded canola straw was not statistically different from non-treated straw. The chopper consumed highest (3.15 +/- 0.09 kWh t(-1)) and lowest (1.96 +/- 0.33 kWh t(-1)) specific energy to chop barley and canola straw, respectively. The highest and lowest specific energy was consumed by wheat (42.57 +/- 2.04 kWh t(-1)) at 1.6 mm and canola (1.46 +/- 0.30 kWh t(-1)) straws ground using 30 mm hammer mill screen size, respectively. For steam exploded agricultural biomass, the highest and lowest specific energy was consumed by oat (33.18 +/- 3.10 kWh t(-1)) at 1.6 mm and canola (2.69 +/- 0.26 kWh t(-1)) straws ground using 6.4 mm hammer mill screen size, respectively. Specific energy required by hammer mill to grind non-treated and steam exploded barley, canola, oat and wheat straw showed a negative power correlation with hammer mill screen sizes. (C) 2010 Elsevier Ltd. All rights reserved.
  • 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:
    • 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:
    • 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:
    • Leroux, X.
    • Attard, E.
    • Lemaire, G.
    • Laurent, F.
    • Chabbi, A.
    • Nicolardot, B.
    • Poly, F.
    • Recous, S.
  • Source: Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world, Brisbane, Australia
  • Year: 2010
  • Summary: The COSMOS-Flux project aimed at studying two situations that have important environmental impacts at a larger scale : the conversion tillage no tillage where different tillage systems have been applied for 14 years at the start of experiment; the conversion grassland annual crop where the introduction of temporary grassland into rotations is studied. The characterization of upper layers of soil for C and N pools, mineralization, immobilization and nitrification of N, along with characteristics of the nitrifying and denitrifying bacterial communities (activity, size and structure) were followed during 18 to 36 months after conversion. We observed that the tillage of soils untilled for 14 years, or the ploughing of the 5-year old grassland were major disturbances for the soils, which led to a very fast evolution of soil organic matter pools, N fluxes and microbial activities towards the characteristics observed for tilled and arable situations. Conversely, the shifts from till to no-till, and the establishment of grassland on soil previously cropped with annual species did not change significantly their soil characteristics at the time scale of the study. Among soil environmental variables, soil organic carbon appeared as a key driver of the observed responses.