• Authors:
    • Lee, Y.
    • Kwak, Y.
    • Lee, S.
    • Choi, K.
    • Seo, Y.
    • Kim, M.
    • Yang, S.
  • Source: World Journal of Microbiology and Biotechnology
  • Volume: 28
  • Issue: 4
  • Year: 2012
  • Summary: The present study evaluated the changes of soil microbial communities that were subjected to no-till and compared the results to those subject to tillage for organic farming in a controlled horticultural field by fatty acid methyl ester. Fungi ( P<0.001), gram-positive bacteria ( P<0.001), arbuscular mycorrhizal fungi ( P<0.01), and actinomycetes ( P<0.01) in the no-till soils were significantly larger than those in the tillage soils. The no-till in the subsoil had a significantly lower ratio of cy17:0 to 16:1omega7c compared to that of tillage, indicating that microbial stress decreased because the soils were not disturbed ( P<0.05). Fungi should be considered as a potential factor responsible for the obvious microbial community differentiation that was observed between the no-till and tillage areas in a controlled horticultural field.
  • Authors:
    • Chapagain, T.
    • Riseman, A.
  • Source: American Journal of Plant Sciences
  • Volume: 3
  • Issue: 5
  • Year: 2012
  • Summary: A cultivar trial, including commercial and heirloom cultivars of major cereals and grain legumes was conducted in Vancouver, BC, under low input organic conditions. We assessed 19 wheat (6 commercial and 13 heirloom), 17 barley (8 commercial and 9 heirloom), 5 pea, 5 favabean, 5 kidneybean, 2 lentil, and 2 soyabean cultivars for plant performance metrics, and their potential in a small grain:legume intercropping system. Heirloom wheat cultivars showed notable response in a number of parameters including late maturity, taller plants, greatest number of spikes per m 2, longest spike, highest number of seed per spike, greater seed weight to volume ratio, and resistance to stripe rust compared with commercial cultivars. For the heirloom-type, 6 of 14 wheat cultivars, ( i.e., "Reward", "Glenn", "Cerebs", "Red Bobs", "Sounders" and "Black Bearded") produced yields comparable to the commercial cultivars ( i.e., nearly 5 t/h or higher). Also, heirloom cultivars typically contained higher protein levels most suitable for baking and blending purposes with "Einkorn" displaying the highest level (16.2%). Heirloom and commercial barley cultivars did not differ significantly with respect to plant height, spike length, and seed weight to volume ratio. However, a number of heirloom cultivars (e.g., "Jet", "Dolma", "Andie" and "Himalayan") displayed greater responses on earliness, number of spikes per m 2, grain yield, protein content and seed weight to volume ratio. Pea and lentil yielded lower than the national average under trial conditions. However, heirloom peas "Corgi", "De Grace", "Snowbird", and "Golden" were earlier compared to the commercial cultivar "Reward". All kidney bean cultivars yielded ~3 t/h with the highest yield from "Red Kidney" (3.8 t/h). Fava and soyabean appeared as promising crops as the cultivars produced good growth and yields. Neither lentil ("Crimson" and "Essex") produced satisfactory responses though they had excellent vegetative growth and flowered. Therefore, significant variation was observed including several heirloom cultivars displayed great potential in terms of yield, protein content, and disease resistance and that specific cultivars were better suited for an intercropping system.
  • Authors:
    • Quideau, S.
    • Pswarayi, A.
    • Nelson, A. G.
    • Frick, B.
    • Spaner, D.
  • Source: Agronomy Journal
  • Volume: 104
  • Issue: 3
  • Year: 2012
  • Summary: To investigate intercropping as a management strategy to increase crop productivity and weed suppression in organic systems, spring wheat ( Triticum aestivum L.), barley ( Hordeum vulgare L.), canola ( Brassica napus L.) and field pea ( Pisum sativum L.) monocultures were compared with two-, three-, and four-crop intercrops containing wheat at two organic and one conventional site in 2006 and 2007, central Alberta, Canada. We measured crop and weed biomass, grain yield, and crop competitiveness against weeds from a replacement design in a completely randomized block experiment. Pea and canola monocrops on organic sites yielded the least of all crop treatments. Conventional crop treatments generally yielded higher than organic treatments. Few land equivalent ratios (LERs) on organic sites were significantly >1.0. Some wheat intercrops without barley showed overyielding (LER >1.0) potential. Most of the significant LERs were from three- and four-crop intercrops. More than 50% of the intercrops on organic sites significantly suppressed weeds (based on relative weed biomass) and most of these intercrops had barley in the mixture. Barley as a sole crop and in intercrops suppressed weeds better than all other intercrops and sole crops. The wheat-canola intercrop exhibited the best weed suppression of the two-crop intercrops on organic and conventional sites. The crop densities used in this study may have contributed to the extremely low pea and canola monocrop yields as well as low LERs. Due to this, our findings should be regarded as showing trends and potential from intercrops only. We therefore recommend further studies to establish ideal densities for the intercrops used.
  • Authors:
    • Gaillard, B.
    • Foissy, D.
    • Dorvillez, D.
    • Carrouee, B.
    • Boucheny, P.
    • Biarnes, V.
    • Bedoussac, L.
    • Baranger, E.
    • Al-Rifai, M.
    • Naudin, C.
    • Corre-Hellou, G.
    • Makowski, D.
    • Bazot, M.
    • Pelzer, E.
    • Guichard, L.
    • Mansard, M.
    • Omon, B.
    • Prieur, L.
    • Yvergniaux, M.
    • Justes, E.
    • Jeuffroy, M.
  • Source: European Journal of Agronomy
  • Volume: 40
  • Year: 2012
  • Summary: Intensive agriculture ensures high yields but can cause serious environmental damages. The optimal use of soil and atmospheric sources of nitrogen in cereal-legume mixtures may allow farmers to maintain high production levels and good quality with low external N inputs, and could potentially decrease environmental impacts, particularly through a more efficient energy use. These potential advantages are presented in an overall assessment of cereal-legume systems, accounting for the agronomic, environmental, energetic, and economic performances. Based on a low-input experimental field network including 16 site-years, we found that yields of pea-wheat intercrops (about 4.5 Mg ha -1 whatever the amount of applied fertiliser) were higher than sole pea and close to conventionally managed wheat yields (5.4 Mg ha -1 on average), the intercrop requiring less than half of the nitrogen fertiliser per ton of grain compared to the sole wheat. The land equivalent ratio and a statistical analysis based on the Price's equation showed that the crop mixture was more efficient than sole crops particularly under unfertilised situations. The estimated amount of energy consumed per ton of harvested grains was two to three times higher with conventionally managed wheat than with pea-wheat mixtures (fertilised or not). The intercrops allowed (i) maintaining wheat grain protein concentration and gross margin compared to wheat sole crop and (ii) increased the contribution of N 2 fixation to total N accumulation of pea crop in the mixture compared to pea sole crop. They also led to a reduction of (i) pesticide use compared to sole crops and (ii) soil mineral nitrogen after harvest compared to pea sole crop. Our results demonstrate that pea-wheat intercropping is a promising way to produce cereal grains in an efficient, economically sustainable and environmentally friendly way.
  • Authors:
    • Jansone, Z.
    • Vicupe, Z.
  • Source: Zinatniski praktiskas konference, "Zinatne Latvijas Lauksaimniecibas Nakotnei: Partika, Lopbariba, Skiedra un Energija"
  • Year: 2012
  • Summary: The objectives of the present study were to compare oat genetic material according to its phenological traits under organic and conventional conditions. The field trials in two management systems (plot size 10 m 2, 3 replicates) were carried out in 2010 and 2011 at State Stende Cereal Breeding Institute. Twenty-one oat genotypes from the breeding program were chosen for this experiment. The phenological traits: field germination (growing stage/GS10), tillering (GS21), stem elongation (GS30), flag leaf emergence (GS 42-43), panicle stage (GS50-52) and maturity (GS92) were determined. The significant genotypic variation noted for most of the evaluated traits indicated the possibility of selection for these traits in oat. As the t-test indicated, the oat genotypes grown in organic conditions had significantly (p
  • Authors:
    • Burke, I.
    • Snyder, A.
    • Pittmann, D.
    • Gallagher, R.
    • Koenig, R.
    • Borrelli, K.
    • Hoagland, L.
    • Fuerst, E.
  • Source: Journal of Sustainable Agriculture
  • Volume: 36
  • Issue: 4
  • Year: 2012
  • Summary: The nitrogen (N) dynamics of nine rotation systems designed to transition dryland cereal to organic production in eastern Washington State were examined. Systems combined cereal and legumes for grain, forage (FOR), and green manure (GRM). Few differences in N balances and soil inorganic N levels were found among transition systems when poor spring crop establishment resulted in competition from weeds. However, FOR and winter GRM crops produced adequate stands that were competitive with weeds and increased residual soil inorganic N in the final year of the transition. Winter legumes and continuous FOR systems demonstrated the greatest potential to provide a sustainable inorganic N source to subsequent organic cereal crops.
  • Authors:
    • Özbek, N.
    • Göre, M. E.
    • Erdoğan, O.
  • Source: Bitki Koruma Bülteni
  • Volume: 52
  • Issue: 1
  • Year: 2012
  • Summary: The effects of barley and common vetch on Verticillium wilt intensity were examined at Nazilli Cotton Reserach experiment fields during 2006-2007. Applications used in experiment were planted as barley, barley+common vetch, common vetch (traditional production), common vetch (growing at last irrigation) and control (conventional cotton production). After a four weeks residue decomposition period, seeds of Nazilli 84-S cotton variety were planted in a randomized complete block design with four replications. The data for disease intensity were determined during the stage of 5-10%, 50-60% cotton boll opening and after harvest. Seed cotton yield and fiber quality properties were also determined. Disease intensity identified according to symptoms on leaf and cross section of stems was determined lower level in organic growing plots and it was followed by control growing plot. During experiments, green manure applications of barley and barley+common vetch provided with a larger decrease on disease intensity than control growing plot. This also shows that cotton growing increase disease intensity every year. In common vetch and control plots, average yield values were determined higher according to barley+common vetch and barley growing plots. Cotton fiber properties have not been affected by these treatments.
  • Authors:
    • Carr, P. M.
    • Anderson, R. L.
    • Lawley, Y. E.
    • Miller, P. R.
    • Zwinger, S. F.
  • Source: Renewable Agriculture and Food Systems
  • Volume: 27
  • Issue: Special Issue 01
  • Year: 2012
  • Summary: The use of killed cover crop mulch for weed suppression, soil erosion prevention and many other soil and crop benefits has been demonstrated in organic no-till or zero-till farming systems in eastern US regions and in Canada. Implements have been developed to make this system possible by terminating cover crops mechanically with little, if any, soil disturbance. Ongoing research in the US northern Great Plains is being conducted to identify cover crop species and termination methods for use in organic zero-till (OZ) systems that are adapted to the crop rotations and climate of this semi-arid region. Current termination strategies must be improved so that cover crop species are killed consistently and early enough in the growing season so that subsequent cash crops can be grown and harvested successfully. Delaying termination until advanced growth stages improves killing efficacy of cover crops and may provide weed-suppressive mulch for the remainder of the growing season, allowing no-till spring seeding of cash crops during the next growing season. Excessive water use by cover crops, inability of legume cover crops to supply adequate amounts of N for subsequent cash crops and failure of cover crops to suppress perennial weeds are additional obstacles that must be overcome before the use of killed cover crop mulch can be promoted as a weed control alternative to tillage in the US northern Great Plains. Use of vegetative mulch produced by killed cover crops will not be a panacea for the weed control challenges faced by organic growers, but rather one tool along with crop rotation, novel grazing strategies, the judicious use of high-residue cultivation equipment, such as the blade plow, and the use of approved herbicides with systemic activity in some instances, to provide organic farmers with new opportunities to incorporate OZ practices into their cropping systems. Emerging crop rotation designs for organic no-till systems may provide for more efficient use of nutrient and water resources, opportunities for livestock grazing before, during or after cash crop phases and improved integrated weed management strategies on organic farms.
  • Authors:
    • Espadaler, X.
    • Ribes, J.
    • Ribes, E.
    • Piñol, J.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 158
  • Year: 2012
  • Summary: The Heteroptera assemblage of a citrus grove and how it was affected by ant-exclusion was examined during transformation from conventional to organic agriculture. The results showed that the Heteroptera assemblage changed dramatically over the eight years of the study: at first, it mainly consisted of herbivorous lygaeids and predatory anthocorids but became dominated by predatory mirids in 2008-2009. The predator/herbivore ratio increased steadily over the eight years of the study. Ants can form mutualistic relationships with heteropteran pests. However, exclusion of ants from canopies did not affect the Heteroptera assemblage at the beginning of the study, but had a profound effect later on. In particular, ant-exclusion increased the abundance of most predatory Heteroptera, except for the myrmecomorphic mirid Pilophorus perplexus, which was approximately five times more abundant in control than in ant-excluded trees; the analyses showed that the only mimicked ant species was Lasius grandis.
  • Authors:
    • Hanisch, A.
    • Balbinot Junior, A.
    • Vogt, G.
  • Source: Revista de Ciencias Agroveterinarias
  • Volume: 11
  • Issue: 1
  • Year: 2012
  • Summary: The objectives of this work were to evaluate the forage yield of three pearl millet genotypes under different chicken manure rates and to verify the residual effect of this organic fertilizer on soil. An experiment was carried out in Papanduva, Santa Catarina, Brazil, during the 2008/09 and 2009/10 crop seasons. In the first crop season, three pearl millet genotypes were evaluated: a common genotype and two hybrids (ADR 500 and LAB 733), which were cultivated under four chicken manure rates (0, 4, 8 and 12 t ha -1). In succession, the multicropping (black oat+common vetch) and pearl millet were cultivated to evaluated the residual effect of this organic fertilizer. The experimental design was a randomized blocks, with four replications. The pearl millet production was evaluated by cuts, while in multicropping between black oat+common vetch was evaluated the total dry mass. There was interaction between pearl millet genotypes and manure rates in relation to total shoot dry mass. The hybrid genotypes showed the higher performance due to increase manure rate. There was residual effect of this organic fertilizer on the multicroping of black oat+common vetch and pearl millet.