• Authors:
    • Gyuricza, C.
    • Bencsik, K.
    • Ujj, A.
    • Singh, M. K.
  • Source: Cereal Research Communications
  • Volume: 33
  • Issue: 1
  • Year: 2005
  • Authors:
    • Chattopadhyay, N.
    • Das, H. P.
  • Source: Advances in Indian entomology: productivity and health (a silver jubilee supplement)
  • Volume: 1
  • Issue: 3
  • Year: 2005
  • Summary: Every year crops (such as rice, cotton, pigeon pea, sorghum, soyabean, groundnut, sugarcane and vegetables) are being damaged by pests and diseases. Due to lack of proper operational forecasting system for the incidences of pests and diseases, it becomes difficult to adopt efficient plant protection measures at the right time. It has been established with fair degree of accuracy that climate/weather plays major role in the incidences of pests and diseases. Thus, there is a tremendous scope of utilizing meteorological parameters for the advance information of the occurrences of the pests and diseases and ultimately scheduling of prophylactive measures can be taken scientifically and judiciously. Quite a number of studies in this regards have been made in the Agricultural Meteorology Division, India Meteorological Department (Pune, Maharashtra, India). In the present paper, a comprehensive review of the work done in this division on the impact of weather on pests and diseases of crops is presented. This information will probably help the agricultural community of the country to save the crops from the infestation of pest and disease incidences.
  • Authors:
    • Sturny, W. G.
    • Ramseier, L.
    • Chervet, A.
    • Tschannen, S.
  • Source: Revue Suisse d'Agriculture
  • Volume: 12
  • Issue: 5
  • Year: 2005
  • Summary: Over the last ten years, conventional plough tillage has been compared to no-tillage on six crop rotation plots in the long-term field trial Oberacker at the Inforama Ruetti in Zollikofen, Switzerland. The deep cambisol of the trial plots contains 15% clay and 3% organic matter. The absence of tillage operations in no-tillage makes a more complex strategy for weed control necessary. Options such as a balanced crop rotation, permanent soil cover, adapted crop residue management and immediate seeding of subsequent crops are used alongside chemical, mechanical, and thermal strategies of weed control. Land use is sustainable in the no-tillage system: No-tilled soil has a higher structural stability and load capacity while being markedly less prone to erosion; less machine usage and traffic reduce (fuel) costs. After seven years of no-tillage, continuous release of soil-borne nitrogen leads to crop yields and qualities at least equal to those obtained with conventional tillage. Two challenges remain only partly solved: (a) the greater dependence on herbicides such as glyphosate and (b) the greater risk of mycotoxin formation in no-tilled winter cereal crops that follow maize. Remedies include adaptations of the crop rotation, chopping of residual maize straw/stalks and cropping of cereal varieties less susceptible to fusarium. In conclusion, no-tillage contributes substantially to maintaining soil fertility on a long-term basis.
  • Authors:
    • Prado A., R. del
    • Diaz S., J.
    • Espinoza N., N.
  • Source: XVII Congreso de la Asociación Latinoamericana de Malezas (ALAM) I Congreso Iberoamericano de Ciencia de las Malezas, IV Congreso Nacional de Ciencia de Malezas, Matanzas, Cuba, 8 al 11 de noviembre del 2005, pp. 326
  • Year: 2005
  • Summary: Eight biotypes of herbicide-resistant weeds have been described in Chile. All belong to grass weeds, specifically wild oat ( Avena fatua), ryegrass ( Lolium rigidum), Italian ryegrass ( L. multiflorum) and crested dogtailgrass ( Cynosurus echinatus), which are the most common in the main wheat, barley, oats, lupin and canola producing area (36degreesS to 39degreesS). The biotypes have shown resistance to ACCasa, ALS and EPSP inhibitors. Most biotypes have appeared in farm fields subjected to intensive land use, with annual crops, with a trend to wheat monoculture in some cases, and with intense use of no-till and herbicides with similar mode of action. Herbicides most frequently used have been glyphosate (EPSP), diclofop-methyl and clodinafop-propargyl (ACCasa). Cross-resistance to ACCasa was found in some biotypes of wild oat and ryegrass, with greater resistance to aryloxyphenoxypropionates than to cyclohexanediones. All ACCasaresistant biotypes were susceptible to iodosulfuron and flucarbazone Na (ALS). These two herbicides are recommended for wheat and began to be used just recently in the country. Two biotypes of Italian ryegrass were found resistant to glyphosate. One of these biotypes showed, in addition, resistance to ALS; that is to say, showed multiple resistance. Also the crested dogtailgrass biotype showed multiple resistance to ACCasa and ALS.
  • Authors:
    • NASDA
  • Year: 2004
  • Authors:
    • Arshad, M. A.
    • Franzluebbers, A. J.
    • Azooz, R. H.
  • Source: Soil & Tillage Research
  • Volume: 77
  • Issue: 1
  • Year: 2004
  • Summary: Conservation tillage has become a major soil management strategy to reduce soil erosion and improve soil quality, yet the impacts of crop rotation on soil responses to conservation tillage remain poorly described. We investigated the effects of (i) perennial grass cover versus annual cropping and (ii) type of break crop in a wheat (Triticum aestivum L.)-based crop rotation system on surface-soil (0-10 cm) structural and organic matter properties towards the end of a decade of continuous management on an Albic Luvisol in the cold, semiarid region of northwestern Canada. Soil aggregation was at state to resist water erosion more under perennial grass (i.e. bromegrass (Bromus inermis Leyss.) and red fescue (Festuca rubra L.)) than under annual cropping systems (mean-weight diameter of 2.1 and 1.6 mm under perennial and annual systems, respectively). Soil organic C was higher (44 g C kg-1 soil versus 38 g C kg-1 soil), but total soil N was lower (3.5 g N kg-1 soil versus 3.9 g N kg-1 soil) under perennial compared with annual cropping systems. There were few significant differences in soil-structural properties among the various annual cropping systems. The largest effect was greater light-fraction C and N under continuous wheat (4.0 g C kg-1 soil and 0.27 g N kg-1 soil) compared with other rotations, especially wheat-wheat-fallow (2.4 g C kg-1 soil and 0.16 g N kg-1 soil), as a result of higher residue inputs. Relationships between mean-weight diameter of water-stable aggregates and biochemical properties were strongest for soil microbial biomass C and soil organic C. Perennial grass cover exhibited greater potential to preserve soil-structural properties than no-tillage annual cropping.
  • Authors:
    • Andren, O.
    • Katterer, T.
    • Persson, J.
  • Source: Nutrient Cycling in Agroecosystems
  • Volume: 70
  • Issue: 2
  • Year: 2004
  • Summary: Land use in general and particularly agricultural practices can significantly influence soil carbon storage. In this paper, we investigate the long-term effects of management changes on soil carbon stock dynamics on a Swedish farm where C concentrations were measured in 1956 at 124 points in a regular grid. The soil was re-sampled at 65 points in 1984 and at all grid points in 2001. Before 1956 most of the fodder for dairy cattle was produced on the farm and crop rotations were dominated by perennial grass leys and spring cereals with manure addition. In 1956 all animals were sold; crop rotations were thereafter dominated by wheat, barley and rapeseed. Spatial variation in topsoil C concentration decreased significantly between 1956 and 2001. C stocks declined in fields with initially large C stocks but did not change significantly in fields with moderate C stocks. In the latter fields, soil C concentrations declined from 1956 to 1984, but increased slightly thereafter according to both measurements and simulations. Thus, the decline in C input due to the altered management in 1956 was partly compensated for by increasing crop yields and management changes, resulting in increased C input during the last 20 years. A soil carbon balance model (ICBM) was used to describe carbon dynamics during 45 years. Yield records were transformed to soil carbon input using allometric functions. Topsoil C concentrations ranging between 1.8 and 2.4% (depending on individual field properties) seemed to be in dynamic equilibrium with C input under recent farming and climatic conditions. Subsoil C concentrations seemed to be unaffected by the management changes.
  • 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:
    • O'Connell, P. J.
    • Allard, J. L.
  • Source: Weed management: balancing people, planet, profit. 14th Australian Weeds Conference, Wagga Wagga, New South Wales, Australia, 6-9 September 2004: papers and proceedings 2004
  • Year: 2004
  • Summary: Australian winter broadacre crops have been planted on 19.4 million ha on average, over the five years 1999-2003. The cropped area is dominated by cereals and in particular wheat. Annual ryegrass (ARG, Lolium rigidum) is the most widespread, difficult to control and important weed of Australian winter broadacre farming systems, and is arguably the greatest threat to sustainability of these systems. It was calculated that it infests ~6 million ha. Syngenta's analyses of herbicide sales suggest that the area treated for annual ryegrass could be as high as 8 million ha. Herbicide sales have been used to estimate the area treated for ARG control. This analysis focuses on herbicides for which there is not yet widespread ARG resistance. Grain producers are heavily dependant on two groups of herbicides. Group M (glyphosate) is applied as a non-selective burn-down treatment prior to planting and is applied to as much as 25 million ha (applied up to 132% of the winter crop area). The Group D herbicides, especially trifluralin, are used for pre-emergent weed control on nearly 7 million ha, 36% of the cropped area, up from 25% in 2001. There is circumstantial evidence that Group D herbicides are mostly applied for the management of ARG, and there is a high risk of over-use. Minimum- and no-tillage are used on 76% of the cropped area, while burning as a weed control technique (hot burn) is used on just over 10% of the area. In view of the current willingness of grain growers to rely heavily upon herbicides for weed control, a greater burden is placed on ensuring herbicide rotational strategies are carefully thought through and implemented. This has resulted in extension of double-knockdown techniques with Spray.Seed to reduce the likelihood of glyphosate resistant ARG in reduced tillage environments. A similar education programme needs to be directed towards Group D herbicides and alternatives promoted. Group K herbicides, including S-metolachlor (Dual Gold), are potential alternatives. Group K herbicides are generally well-tolerated by barley, oats, legumes and canola and can be used at higher rates in these crops. Wheat is less tolerant at the rates required to manage ARG effectively. Rotating to Group K herbicides outside wheat is proposed. The grains industry could evaluate the model the Australian cotton industry has established for the very successful management of insecticide resistance. A better way to manage herbicide use and rotation needs to be found, particularly as fewer new active ingredients are expected to be developed than in the past.
  • Authors:
    • Philip, H.
    • Woods, S.
    • Weiss, R. M.
    • Olfert, O.
    • Dosdall, L.
  • Source: The Canadian Entomologist
  • Volume: 136
  • Issue: 2
  • Year: 2004
  • Summary: Cereal leaf beetle, Oulema melanopus L., is an invasive pest insect of small grain cereal crops, particularly oat, wheat, and barley. The first report of cereal leaf beetle populations in North America came from Michigan in 1962. Surveys indicate that populations have become established throughout eastern North America from Ontario to Alabama and in northwestern North America from Utah to southern British Columbia. The establishment of O. melanopus in western North America has raised concern that its presence is a potential risk to the Canadian cereal industry, especially in the prairie ecozone of western Canada, where up to 10 million hectares of cereal crops are grown annually. Field surveys to date have indicated that O. melanopus has not yet become established in this region. A CLIMEX(TM)model for O. melanopus in North America was developed, based on climate and ecological parameters, and validated with actual distribution records. The actual distribution of O. melanopus in eastern North America matched the predicted distribution well. The model predicts that, once introduced, O. melanopus would readily survive in the cereal-growing areas of western Canada and present a significant risk to cereal production. The potential for establishment of O. melanopus in the prairie ecozone of western Canada substantiates the efforts by regulatory agencies to prevent accidental introduction of this pest species.