• Authors:
    • Al-Tawaha, A.
    • Al-Ghzawi, A.
    • Al-Ajlouni, M.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 8
  • Issue: 3/4 part 2
  • Year: 2010
  • Summary: Field experiments were conducted in North Part of Jordan to determine the best combination of crop rotations and fertilization levels that would improve the productivity of land and increase barley production under dryland conditions. Six-year field trials were conducted from 1996/1997 to 2001/2002 growing seasons at Ramtha Agricultural Research Station in north Jordan. Treatments effect was independent from each other and it is possible to select the best combination of treatments that give the highest yield. Rotation effect varied across growing seasons. Barley/vetch rotation showed the highest productive rotation. Additionally, barley yield was the same after vetch as after fallow. The application of 30 and 80 kg ha -1 of nitrogen and phosphorus, respectively, resulted in the highest values of fertilizer utilization efficiency.
  • Authors:
    • Evansf, R.
    • Lartey, R.
    • Caesar, T.
    • Sainju, U.
    • Lenssen ,A.
    • Allen, B.
  • Source: Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world, Brisbane, Australia, 1-6 August 2010. Division Symposium 3.2 Nutrient best management practices
  • Year: 2010
  • Summary: Available water and N fertility are primary constraints to crop production in the northern Great Plains of the USA. A field trial was initiated in 2004 to compare four crop rotations in a complete factorial of two tillage and two management systems. Rotations were continuous spring wheat (SW), pea-SW, barley hay-pea-SW, and barley hay-corn-pea-SW. Tillage systems were no till and field cultivator tillage, while management systems were conventional and ecological. Conventional management included broadcast nitrogen fertilizer, standard seeding rates, and short stubble height. Ecological management practices varied by crop, and included banded nitrogen fertilizer for cereals, increased seeding rate, delayed planting date for SW, and taller stubble height. Continuous SW grain yield was 26% lower than SW in more diverse rotations. Pea grain yield was 18% lower in 2-yr rotations than in more diverse rotations. Ecologically managed SW yielded 29% less than conventionally managed SW, presumably due to the delayed planting date. Ecological management of pea resulted in 12% greater yield compared to conventional management. Tillage system rarely impacted crop yield. Yield increases in SW were related to increased N use efficiency.
  • Authors:
    • Eslami, S.
    • Ebranimi ,E.
    • Mahmoodi, S.
  • Source: Proceedings of 3rd Iranian Weed Science Congress, Volume 1: Weed biology and ecophysiology, Babolsar, Iran, 17-18 February 2010
  • Year: 2010
  • Summary: Ceratocarpus arenarius is one of the problematic and noxious weeds in dryland farming of wheat, barley, lentil and peas in North Khorasan. Laboratory experiments were conducted on germination and seedling emergence of ceratocarpus. Germination ability of this weed species was similar in light/dark and continuous dark conditions, therefore seeds of this weed species are non-photoblastic. Seeds germinated over 80% in the range of alternating day/night temperatures (20/10, 25/15 and 30/20C) and the maximum germinability (96%) was observed at 25/15C. Seed of this weed species retained their germination ability until high salinity levels and even at 800 mM NaCl 20% of seeds germinated. Seeds of this weed species could tolerate high level of drought stress, so that 25% of seeds germinated at osmotic potential of -1 MPa. Seedlings could emerge from a range of burial depths from 0 (without covering with filter paper) to 8 cm and maximum emergence (94%) was observed in seeds planted on the soil surface covered with 3 layers of filter paper.
  • Authors:
    • Andrew, J.
    • Gazey, C.
  • Source: Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world, Brisbane, Australia, 1-6 August 2010. Symposium 4.1.2 Management and protection of receiving environments
  • Year: 2010
  • Summary: Surface application of agricultural lime to treat acidity in the soil profile delivers multiple benefits to the broadcare dryland farming systems in Western Australia. Soil pH measured in 2009 to a depth of 40-50 cm was increased by applications of lime applied in 1991 and 2000. The ameliorated soil pH profile, which meets the Wheatbelt Natural Resource Management 2025 resource targets (Avon Catchment Council 2005) (designed to remove acidity as a constraint to productive agriculture), has provided multiple benefits in terms of increased productivity, increased crop competitiveness, reduced weed burden, reduced risk of soil erosion by wind due to increased biomass cover and potentially reduced off-site effects which result from decreased water use efficiency on profiles with low pH. Current annual losses due to soil acidity for the WA wheatbelt are estimated at between $300-400 million or around 9% of the total crop. The treated soil profile in this trial returned $175/ha benefit from increased wheat yield in 2008 and $225/ha benefit from increased barley grain yield in 2009.
  • Authors:
    • Fernandez-Quintanilla, C.
    • Izquierdo, J.
  • Source: Agrociencia
  • Volume: 44
  • Issue: 1
  • Year: 2010
  • Summary: Lolium rigidum is a major grass weed of winter cereals in the Mediterranean area, in spite of the continuous use of herbicides in these crops. New management approaches focus on the reduction of the seed banks by enhancing crop competitiveness and, consequently, minimizing weed seed rain. However, the spatial heterogeneity that exists within fields results in differences in the growth and the competitiveness of crops and weeds. In order to determine if the competitive interactions between barley and L. rigidum are site-specific biomass and seed production of this weed, growing in monoculture (plots with L. rigidum) and in mixed culture (plots with L. rigidum+barley), were studied at three sites (in upland, mid-slope and lowland positions) within barley fields. In each site were determined weed populations, and in soil separates, nutrient content, organic matter, slope and orientation were determined for each site. Crop presence significantly reduced weed biomass between 5 and 79% and seeds per spike between 10 and 48%, depending on the site. The competitive effect of the crop was greater in the more fertile sites (with higher N, P and organic matter content). In these sites, differences in plant biomass accumulation between the weed in monoculture and the weed in mixed culture started to be significant after stem elongation. Regardless the reduction in the number of seeds per spike observed in the most fertile sites, seed rain (measured as seeds m -2) could still be very important if weed density of the site is high. The differences in the competitive interactions between barley and L. rigidum observed within the fields suggest that adequate crop husbandry practices addressed site-specifically to enhance crop competitiveness can play an important role as a mechanism to reduce L. rigidum populations over the long term.
  • Authors:
    • Adamczewski, K.
    • Kaczmarek, S.
    • Matysiak, K.
  • Source: Acta Scientiarum Polonorum - Agricultura
  • Volume: 9
  • Issue: 4
  • Year: 2010
  • Summary: The aim of this study was to compare the herbicidal efficiency of mixture florasulam+2,4-D (Mustang 306 SE) in spring wheat cultivar Bryza, spring barley cultivar Antek and oat cultivar Cwa sown in monocrops and two-species mixtures. Field experiments were carried out in 2005-2007 at the Experimental Station in Winna Gora (5212′N; 1727′E), owned by the Institute of Plant Protection - National Research Institute in Poznan. Herbicyd Mustang 306 SE was applied in a dose of 0.5 dm 3.ha -1 at 3-5 leaf stage of cereals using the knapsack sprayer Gloria. The analysis of weed infestation of cereal stand was made with the quantitative-weighing method twice in the growing period (3-4 weeks after the application and 7-8 weeks after the application). Efficiency of herbicide action in mixtures was compared with its effectiveness in monocrops of individual species. From the analyses made it follows that of the cereal mixtures, the barley-oat mixture was infested in the least degree, and the wheat-oat mixture in the most degree. Strongest effect of cultivation in mixtures on reduction of weed infestation was noticeable on the control treatments, where the herbicide was not applied, whereas the cereal cultivation system (pure or mixed sowing) not always differentiated the herbicide efficiency. Cereal grain yields in mixtures after the application of mixture florasulam+2,4-D were significantly higher than yields of at least one of the component, and yields of mixtures harvested from the control treatments exceeded grain yields of both cereal species in monocrops.
  • Authors:
    • Singh, K.
    • Nandita, G.
  • Source: Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world, Brisbane, Australia, 1-6 August 2010. Congress Symposium 4: Greenhouse gases from soils
  • Year: 2010
  • Summary: Management strategies in agroecosystems may influence C balance in soil through variation in C input to soil and also by causing variation in C output from soil. In a two year study we evaluated the effect of application of soil inputs with varying resource quality viz: high quality (C:N 16; HQR), low quality (C:N 82; LQR) and mixed quality (HQR +LQR; MQR) inputs having equivalent amount of N, on the soil CO 2 flux, % C build-up, soil C balance and crop productivity in a tropical dryland rice-barley-summer fallow agroecosystem. Addition of LQR singly resulted in high probability of C retention capacity compared to other treatments, however lower levels of soil C build-up, and crop productivity was observed. On the other hand, although in HQR treatment the C balance approached almost unity, the C build-up and crop productivity was comparable to that of the LQR treatment. Combining the two inputs resulted in significant build-up of soil C and enhancement of crop productivity and also indicated high C sequestration capacity. It is concluded that for sequestration of C, the resource quality of the input i.e., the form of C, labile or recalcitrant, is more important than the absolute amount of C added to the soil through exogenous inputs.
  • Authors:
    • Armstrong, R.
    • Nuttall, J.
  • Source: Australian Journal of Soil Research
  • Volume: 48
  • Issue: 2
  • Year: 2010
  • Summary: Subsoil physicochemical constraints can limit crop production on alkaline soils of south-eastern Australia. Fifteen farmer paddocks sown to a range of crops including canola, lentil, wheat, and barley in the Wimmera and Mallee of Victoria and the mid-north and Eyre Peninsula of South Australia were monitored from 2003 to 2006 to define the relationship between key abiotic/edaphic factors and crop growth. The soils were a combination of Calcarosol and Vertosol profiles, most of which had saline and sodic subsoils. There were significant correlations between EC e and Cl - ( r=0.90), ESP and B ( r=0.82), ESP and EC e ( r=0.79), and ESP and Cl - ( r=0.73). The seasons monitored had dry pre-cropping conditions and large variations in spring rainfall in the period around flowering. At sowing, the available soil water to a depth of 1.2 m (theta a) averaged 3 mm for paddocks sown to lentils, 28 mm for barley, 44 mm for wheat, and 92 mm for canola. Subsoil constraints affected canola and lentil crops but not wheat or barley. For lentil crops, yield variation was largely explained by growing season rainfall (GSR) and theta a in the shallow subsoil (0.10-0.60 m). Salinity in this soil layer affected lentil crops through reduced water extraction and decreased yields where EC e exceeded 2.2 dS/m. For canola crops, GSR and theta a in the shallow (0.10-0.60 m) and deep (0.60-1.20 m) layers were important factors explaining yield variation. Sodicity (measured as ESP) in the deep subsoil (0.80-1.00 m) reduced canola growth where ESP exceeded 16%, corresponding to a 500 kg/ha yield penalty. For cereal crops, rainfall in the month around anthesis was the most important factor explaining grain yield, due to the large variation in rainfall during October combined with the determinant nature of these crops. For wheat, theta a in the shallow subsoil (0.10-0.60 m) at sowing was also an important factor explaining yield variation. Subsoil constraints had no impact on cereal yield in this study, which is attributed to the lack of available soil water at depth, and the crops' tolerance of the physicochemical conditions encountered in the shallow subsoil, where plant-available water was more likely to occur. Continuing dry seasonal conditions may mean that the opportunity to recharge soil water in the deeper subsoil, under continuous cropping systems, is increasingly remote. Constraints in the deep subsoil are therefore likely to have reduced impact on cereals under these conditions, and it is the management of water supply, from GSR and accrued soil water, in the shallow subsoil that will be increasingly critical in determining crop yields in the future.
  • Authors:
    • Krolikowska, M.
    • Gasiorowska, B.
    • Ceglarek, F.
    • Paza, A.
    • Prochnicka, M.
  • Source: Biuletyn Instytutu Hodowli i Aklimatyzacji Roslin
  • Issue: 257/258
  • Year: 2010
  • Summary: The paper presents the results of investigations carried out in 2003-2006 aimed to assess the influence of intercrops, stubble catch crops and spring barley straw on some chemical constituents of potato tubers. The experiment included: I. Intercrop fertilization: control object (without intercrop fertilization), farmyard manure, undersown crop (birdsfoot trefoil, birdsfoot trefoil+Italian ryegrass), stubble catch crop (oil radish) and II. Straw fertilization: without straw, with straw. Plants of potato table cultivar Fianna were cultivated in the first year after organic fertilization. In the collected samples of tubers contents of the following constituents were measured: starch, reducing sugar, total sugar and total protein. The results indicated that intercrop fertilization significantly influenced the contents of the all the four constituents, whereas straw fertilization only affected the contents of starch and total protein. The highest starch content characterized the potatoes fertilized with the mixture of birdsfoot trefoil with Italian ryegrass, or with oil radish, both in combinations with or without straw. The highest content of total protein was found in the potatoes fertilized with birdsfoot trefoil alone or in combination with straw. The lowest content of reducing sugars and of total sugar was recorded with potatoes fertilized with the mixture of birdsfoot trefoil with Italian ryegrass with or without the addition of straw.
  • Authors:
    • Nandita, G.
    • Pratibha, S.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 137
  • Issue: 3/4
  • Year: 2010
  • Summary: Total biological productivity and soil microbial biomass are important characteristics to describe sustainable agroecosystems. We investigated the impact of herbicide, alone or in combination with soil amendments, on crop and weed productivity and microbial biomass in a rice ( Oryza sativa)-barley ( Hordeum vulgare)-summer fallow rotation in a tropical rainfed agroecosystem. Total net productivity (TNP) of crops was greater with herbicide (Butachlor)+chemical fertilizer (NPK), herbicide+farmyard animal manure, and herbicide+green manure ( Sesbania aculeata) than with herbicide+crop residue ( Triticum aestivum straw), herbicide only, and the control without amendment. Weed TNP was highest in the control, lowest in herbicide only, and intermediate in combined herbicide and amendment treatments except herbicide+crop residue. The sum of crop TNP and weed TNP was highest in herbicide+green manure and lowest in herbicide only. Microbial biomass C and N were greater with herbicide and amendment treatments than with herbicide only. Microbial biomass showed distinct temporal variation. Yearly plant input to soil had strong correlation with microbial biomass in the control and herbicide only treatments. In these agroecosystems, combining organic soil amendments with herbicide application could help sustain soil fertility and maintain higher total biological productivity.