- Authors:
- Brandsater, L. O.
- Løes, A. K.
- Riley, H.
- Source: European weed research society. Proceedings of the 6th EWRS workshop on physical and cultural weed control, Lillehammer, Norway, 8-10 March, 2004
- Year: 2004
- Summary: Due to official regulations, Norwegian agriculture is divided into cereal cropping areas with very little animal husbandry, and areas with high livestock density in the coastal and mountain regions. Stockless organic farming requires a good management of green manure crops. This paper presents crop rotations designed for organic farming with low livestock density, combining weed control and nutrient supply. Rotation 1 consists of green manure, followed by barley with subcropped legume, oats and peas, green manure or winter rye, rye, ryegrass-clover, and late planted rapeseed. Rotation 1 is designed for a full-time farmer with good access to cultivated land, where 66% of the land is used for cereals and rapeseed, and 34% for green manure. Rotation 2 consists of cereal or lettuce, followed by 4-5 rotations of ley, then potatoes, green manure, cabbage with early mulch, and carrots with late mulch. Rotation 2 is designed for a part-time farmer with less farmland who wants to keep the land in shape and produce some cash crops, but cannot manage to cultivate all the farmland intensively. Forty-four percent of the land is then used for vegetables and herbs, and 56% to produce mulch or green manure crops. Green manure and mulch leys must be cut regularly to control perennial weeds.
- Authors:
- Riley, H.
- Løes, A. K.
- Brandsæter, L. O.
- Source: European weed research society. Proceedings of the 6th EWRS workshop on physical and cultural weed control, Lillehammer, Norway, 8-10 March, 2004
- Year: 2004
- Summary: Due to official regulations, Norwegian agriculture is divided into cereal cropping areas with very little animal husbandry, and areas with high livestock density in the coastal and mountain regions. Stockless organic farming requires a good management of green manure crops. This paper presents crop rotations designed for organic farming with low livestock density, combining weed control and nutrient supply. Rotation 1 consists of green manure, followed by barley with subcropped legume, oats and peas, green manure or winter rye, rye, ryegrass-clover, and late planted rapeseed. Rotation 1 is designed for a full-time farmer with good access to cultivated land, where 66% of the land is used for cereals and rapeseed, and 34% for green manure. Rotation 2 consists of cereal or lettuce, followed by 4-5 rotations of ley, then potatoes, green manure, cabbage with early mulch, and carrots with late mulch. Rotation 2 is designed for a part-time farmer with less farmland who wants to keep the land in shape and produce some cash crops, but cannot manage to cultivate all the farmland intensively. Forty-four percent of the land is then used for vegetables and herbs, and 56% to produce mulch or green manure crops. Green manure and mulch leys must be cut regularly to control perennial weeds.
- Authors:
- Harker, K. N.
- Newman, J. C.
- O'Donovan, J. T.
- Clayton, G. W.
- Source: Weed Technology
- Volume: 18
- Issue: 3
- Year: 2004
- Summary: Glyphosate-resistant canola was seeded at Vegreville, Alberta, in 1997 and 1999 and barley in rotation with the canola in 1998 at three seeding rates. The effects, at each crop seeding rate, of variable glyphosate (canola) and tralkoxydim plus bromoxynil plus MCPA (barley) rates on crop yield, net economic return and seed production by wild oat, wild mustard, and wild buckwheat, and the amount of weed seed in the soil seed bank was determined. Crop seeding rate influenced the response of canola and barley yield and weed seed production to herbicide rate. At the lowest crop seeding rates, yield responses tended to be parabolic with yields increasing up to one-half and three-quarters of the recommended herbicide rates and trends toward reduced yields at the full rates. This response was not evident at the higher crop seeding rates, where, in most cases the yield reached a maximum between one-half and the full recommended rate. The effects of the herbicides on weed seed production, especially at the lowest rate, were often superior at the higher crop seeding rates. The results indicate that seeding canola and barley at relatively high rates may reduce risk associated with lower crop yields and increased weed seed production at lower than recommended herbicide rates. However, the current cost of herbicide-resistant canola seed may preclude the adoption of this integrated weed management practice by growers.
- Authors:
- Source: Kormoproizvodstvo
- Issue: 10
- Year: 2004
- Summary: Ways of increasing the productivity of 1 ha of arable land under fodder crops in the central zone of Belarus are discussed including the use of sequential cropping. Investigations were conducted to determine productivity and quality of various fodder mixtures at different harvest dates of cover crops, as well as compare the effectiveness of use of land under monoculture of fodder barley, sowing dates, soil cultivation methods, and nitrogen fertilizer doses used in oilseed radish and rape sown after barley harvest. Field trials were conducted with Pukhovchanka winter rye, Belotserkovskaya spring vetch, Lutch annual ryegrass, Erbgraf oat, Nemiga spring triticale, Syabra barley, Prygazhunya oiseed radish and Smak spring rape. Data are tabulated on dry matter content and protein yield obtained from various fodder mixtures used for oversowing in winter rye during 1995-98. Data are included on productivity of crop mixtures used for oversowing during 1996-98. The importance of choosing the optimal sowing date for increase of fodder yield using oilseed rape as an additional fodder crop after harvesting the main crop, i.e. barley, and the optimal soil cultivation method for growing of rape after barley is outlined. Data are tabulated on the effect of sowing dates, soil cultivation method and nitrogen doses on yield of oilseed radish and rape grown after barley. Data are included on qualitative parameters of green fodders produced in the multiple cropping systems. Data are tabulated on efficiency of energy use in intensive cropping systems in fodder crop monocultures.
- Authors:
- Clayton, G. W.
- Harker, K. N.
- Soon, Y. K.
- Source: Soil Science Society of America Journal
- Volume: 68
- Issue: 2
- Year: 2004
- Summary: We evaluated weed competition effects on the N economy of field pea (Pisum sativum L.) and the subsequent crop to address the paucity of such information. Plots were seeded to pea, canola (Brassica napus L.) and barley (Hordeum vulgare L.) in 1997 and 1998. Weeds, augmented by cross-seeding experimental plots with oat (Avena sativa L.), were removed with herbicides one and four weeks after crop emergence (WAE). The subsequent barley crop received 0 or 6 g N m(-2). Mean percentage of N derived from the atmosphere (%Ndfa) for the 2 yr, estimated by N-15 isotopic dilution, was 81% for the 4-WAE treatment and 51% for the 1-WAE treatment, indicating that a pea plant subjected to greater weed competition derived more of its N from symbiotic fixation. Total N fixed by pea was not affected by the time of weed removal, however, and total N uptake and seed yield were greater with early weed removal due to less competition for soil N. Early weed removal resulted in net N export in pea seeds (because of higher production) while later weed removal resulted in gains of 1.1 to 1.3 g N m(-2). However, time of weed removal during pea cultivation had no effect on the yield or N uptake of the subsequent barley crop. Higher barley yield and N uptake following pea than following barley were mostly the result of greater N availability. Nitrogen fertilization benefited the subsequent barley regardless of preceding crop type.
- Authors:
- Source: HGCA recommended list 2004/05 for cereals and oilseeds
- Year: 2004
- Summary: Descriptions are provided for cultivars of cereals (winter, late autumn and spring wheat, winter and spring barley, winter rye, winter triticale, and winter and spring oat) and oilseeds (winter and spring oilseed rape and spring linseed) recommended for cultivation in the UK in 2004/05.
- Authors:
- Source: Zashchita i Karantin Rastenii
- Issue: 12
- Year: 2004
- Summary: Wild oat (Avena fatua) is widely spread in cereals, particularly wheat, barley and oat, in many regions of Russia, causing up to 40% losses of crops, and a decrease of quality of seed material, and food and feed grains. Investigations carried out in the Orlov region, European Russia, revealed significant infestations of agricultural crops, particularly winter and spring wheat, and pea, with wild oat. Data are tabulated on herbicides effective against Poaceae weeds including A. fatua in sugarbeet, sunflower, soyabean, rape, potato and vegetable crops. Strategies for prevention and control of A. fatua are discussed. Data are also tabulated on herbicides showing activity against Poaceae and dicotyledonous weeds, as well as A. sativa in maize, sugarbeet, sunflower, soyabean, rape, potato and vegetable crops.
- Authors:
- Source: Weed Science
- Volume: 52
- Issue: 4
- Year: 2004
- Summary: Laboratory experiments were conducted to determine the effects of oxygen concentration (21, 10, 5 and 2.5%), exposure to light, and osmotic potential on the germination of wheat, canola [rape] and various weed species, i.e. barnyardgrass ( Echinochloa crus-galli), catchweed bedstraw ( Galium aparine), curly dock ( Rumex crispus), dandelion ( Taraxacum officinale), foxtail barley ( Hordeum jubatum), green foxtail ( Setaria viridis), perennial sowthistle ( Sonchus arvensis), wild mustard ( Brassica kaber), wild oat ( Avena fatua) and field pennycress ( Thlaspi arvense). Germination of most species increased as osmotic potential was increased. Seed germination for some species like barnyardgrass was inhibited by the combination of exposure to normoxic (21% oxygen) conditions and light. This combination of conditions may function as a signal to prevent soil surface germination. Wild mustard germination increased with increasing oxygen concentration when seeds were not exposed to light, whereas green foxtail germination was relatively insensitive to oxygen concentration. Wild oat germination increased with increasing osmotic potential, and osmotic potential had a greater influence when the seeds were exposed to light. Dandelion, foxtail barley, curly dock and perennial sowthistle germination was affected more by osmotic potential and light exposure than by oxygen concentration. A better understanding of the mechanisms of depth detection for specific species will lead to a better understanding of their recruitment biology. This information may help model the potential for invasion and proliferation of each species as well as devise improved management strategies.
- Authors:
- Hrstkova, P.
- Chloupek, O.
- Schweigert, P.
- Source: Field Crops Research
- Volume: 85
- Issue: 2-3
- Year: 2004
- Summary: Officially published data for the Czech Republic (CR) from 1920 to 2000 and for selected European countries (mostly from 1960 to 2000) were analysed. In the last 40 years, the yield of the five main crops was comparable with European Union (EU) for wheat, barley and rape, but lower for potato and sugar beet. The fastest yield growth was found for flax (2.15% per year), maize and wheat (1.61 and 1.53%), while growth was slower for hops and root crops and slowest for grassland hay (0.22%). The highest yield variation caused by individual years was for wine grapes (32.5%), poppy, edible legumes and flax (18.5-18.3%), while the lowest level of variation was for cereals, i.e. oats, barley, wheat, rye and hay from arable land (9.7-12.0%). For many crops, yield variation decreased over time. The most adaptable crops, whose yield increased most in fertile years, were flax, wheat, edible legumes, maize, rape and barley (regression coefficient of 1.76-1.24), while the lowest level of adaptability was shown by hops, sugar beet, hay from grassland and poppy (0.68-0.14). The higher the level of adaptability the higher the yield growth over the 75 years analysed. The differences in yield of the most commonly grown crops between the EU and the CR can be explained by the different levels of adaptability of the crops in the two regions. Of the five most commonly grown CR crops, wheat was the most adapted crop in 7 of the 10 European countries studied (without regard to other countries), and sugar beet was the least adapted in 6 countries, Within the 10 countries analysed (without regard for the adaptability of the crop in particular countries) wheat, rape and sugar beet were most adaptable in Spain; barley was most adaptable in Italy; and potato was most adaptable in Hungary. The crops in other countries showed more stability across years. Yields of these five crops in the 10 countries were correlated to each other, with only the yield of potato and sugar beet in the former Soviet Union and that of rape in United Kingdom not being influenced by general factors affecting other countries. The higher the yield of sugar beet in a country of the 10 evaluated, the higher was its adaptability in that country (r = 0.717*). Crop diversity in the CR decreased significantly over the period. Each year the percentage of the three most commonly grown crops increased by 0.41% (percentage of the five most commonly grown crops by 0.14%). The percentage of particular cereals on arable land (wheat 23.0%, barley 17.1%, rye 5.1%, oat 5.2%) and their yields were related to their response to fertilisation over the last 40 years. The average temperature increased significantly during the last 50 years, on average by 0.021 degreesC each year, but in the last 10 years by 0.087 degreesC each year. These climate changes were favourable for the most of the commonly grown crops (wheat, barley, rape, sugar beet, rye, maize and legumes), since the crops gave higher yields in warmer years that were accompanied by more hours of sunshine. The other crops were indifferent to climate changes. Fertilisers have been used in the CR to a greater extent since 1946/1947 (22 kg of nutrients per hectare) with maximum usage in 1985/1986 (273 kg ha(-1), including 105 kg N, 86 kg P and 82 kg K). The consumption rate of nutrients increased by 2.91 kg ha(-1) annually from 1918 to 2000, as found by the regression coefficient. One kilogram of nutrients (N + P + K) increased yields of cereals by 6.7-10.1 kg ha(-1) of grain, rape by 5.2, root crops by 26.1-37.8, hops and wine grapes by 2.0-2.6 kg ha(-1). Yield growth due to fertilisation varied from 9.1% (hay from arable land) up to 84.1% (hops) of the entire growth (=100%). The percentage in grain crops (cereals, grain legumes and rape) was 54.3 (maize)-69.8% (barley), and 63.3% on average in the eight crops. It was also similar in root crops, but only 13.4% for wine grape yields. The highest yield growth per 1 kg of nutrients from fertilisers was found in wheat, rape, sugar beet and potato at the level of application of 70-120 kg ha(-1) nutrients. The efficiency of applied nutrients was higher in years with average precipitation than in years with over-average precipitation, and much higher than in dry years. The yield growth for 1 kg nutrients in all grain crops was lowest in years with average temperature, and highest in most of the crops in years with low mean annual temperature. The estimated balance of nitrogen (applied nitrogen in fertilisers minus nitrogen utilised in harvested crops) was negative during 1947-1960, positive during 1970-1990, and slightly negative again from 1995 to 2000. The surplus of applied mineral nitrogen reached in the years of positive balance was 18.5-36.8 kg ha(-1). The impact of the weather was less than the influence of fertilisation. The dynamics of yield in Germany was studied by multiple regression analysis from 1946 to 1999. The annual increase of wheat yield was 50 kg ha(-1), and per kilogram of N-fertiliser by 10 kg ha(-1). The increase per year in the multiple regression was only 73% of the increase in the simple regression. Therefore, 27% of the increase was related to N-fertilisation (and also to other inputs). The corresponding figures were 25% for rye, 30% for rape, 36% for oats, 47% for potato and 66% for flax. No significant influence of N-fertiliser could be found for other crops. It is concluded that those crops exhibiting the highest increase in yield in the CR over the 75 years investigated were also the most adaptable to inter-annual variability in weather, cultivars grown and to cultivation technologies used. The least adapted crop across 10 European countries was sugar beet, for which adaptability was correlated to yield in the particular country. Among the factors studied, the high response to fertilisation was an important factor in the adaptability of particular crops over the 75 years studied. The adaptability of crops to inter-annual variation is therefore a very important trait for consideration by plant breeders. (C) 2003 Elsevier B.V. All rights reserved.
- Authors:
- McRae, F. J.
- Francis, R. J.
- Dellow, J. J.
- Source: Weed control in winter crops 2004
- Year: 2004
- Summary: This publication is a guide to chemical weed control in fallows, wheat, barley, oats, cereal rye, triticale, rape, safflower, lentil, linseed, lupin, chickpea, faba bean and field pea in New South Wales, Australia.