• Authors:
    • Camara, F.
    • Mogor, A.
  • Source: Bioscience Journal
  • Volume: 25
  • Issue: 3
  • Year: 2009
  • Summary: A study was conducted to evaluate the effect of soil covering with black oat straw or black plastic on the phosphorus and potassium content as well as biomass production of three cultivars of lettuce in organic system. There were five handling systems for soil covering: without cover, covered with black plastic, covered with laying oats, covered with harvested oats, and covered with oats straw in natural form. Butter head lettuce showed the highest phosphorus content. Soil covering with oat straw promoted higher potassium accumulation and lettuce production in the second year, while soil covering with black plastic promoted lettuce production in first year.
  • Authors:
    • Camara, F.
    • Mogor, A.
  • Source: ACTA SCIENTIARUM-AGRONOMY
  • Volume: 31
  • Issue: 4
  • Year: 2009
  • Summary: The goal of this research was to evaluate the effect of soil covering with black oat straw, as well as soil covered with black plastic, on the production of biomass and levels of Mn and Zn in lettuce produced in an organic system, over two consecutive years. Five treatments were used: soil without cover, covered with black plastic, covered with laying oats, covered with harvested oats, and covered with oat straw in natural form, for growing three cultivars of lettuce. A randomized blocks design was used in a split-plot system, with four replications. It was concluded that soil covered with oat straw promoted satisfactory lettuce production, as well as adequate Mn and Zn content in plants, equivalent to those found in studies conducted under different growing systems; the soil covered with black plastic promoted satisfactory production and higher Zn content after the first year, and lower Mn content after the second year.
  • Authors:
    • Vargas, L.
    • Nohatto, M.
    • Amarante, C.
    • Mafra, A.
    • Pelizza, T.
  • Source: REVISTA BRASILEIRA DE FRUTICULTURA
  • Volume: 31
  • Issue: 3
  • Year: 2009
  • Summary: Soil cover is one of the options for weed management in the orchard but this might affect fruit trees development. The objective of this work was to evaluate apple trees growth during the orchard establishment stage by using different materials and soil cover plants. The experimental apple orchard was planted in 2003, in Vacaria, RS, Southern of Brazil, with the cv. Galaxy managed under organic system. The experiment followed the randomized block design, with three replications. The treatments were applied in the tree rows, as follows: control (without weed management), manual weeding, black plastic film, black net, pinus sawdust, pinus needle mulch, Andropogon sp. mulch, annual ryegrass ( Lolium multiflorum), black oat ( Avena strigosa), black oat+common vetch ( Vicia sativa), black oat+fodder radish ( Raphanus sativus), annual ryegrass+white clover ( Trifolium repens)+spontaneous plant cover, weed mowing. The soil covered by weeds was monthly measured, during the spring/summer season, over the second and third years of the orchard establishment, and this was related to the apple trees growth. The treatments with manual weeding, black plastic film, pinus needle and Andropogon mulch maintained the soil cover by weeds below 20%. The apple tree height and diameter decreased with the increase of soil cover by weeds, reflecting weeds competition with apple trees.
  • Authors:
    • Penfold, C. M.
    • McNeill, A. M.
  • Source: Crop and Pasture Science
  • Volume: 60
  • Issue: 2
  • Year: 2009
  • Summary: Maintenance of available phosphorus (P) is a problem faced by both conventional and organic systems but it is exacerbated in the latter given that manufactured inorganic sources of P fertiliser are not permitted under the International Federation of Organic Agriculture Movements certification guidelines. The focus of this paper is a discussion of potential agronomic strategies to assist in sustainable management of the soil P resource in organic and low-input broadacre farming systems within the Australian rain-fed cereal-livestock belt. The paper considers three broad strategies for agronomic management of P in this context and draws on reported research from overseas and within Australia. An analysis of the current knowledge suggests that the option most likely to ensure that soluble P is not a limitation in the system is the importation of allowable inputs that contain P from off-farm, although for much of the Australian cereal-livestock belt the immediate issue may be access to economically viable sources. Research targeted at quantifying the economic and biological benefits to the whole-farm system associated with the adoption of these practices is required. Improving the P-use efficiency of the system by incorporating species into rotation or intercropping systems that are able to use P from less soluble sources has been a successful strategy in parts of the world with climate similar to much of the Australian cereal-sheep belt, and deserves further research effort in Australia. Agronomic management to maximise quantity and quality of pasture and crop plant residues undoubtedly builds labile soil organic matter and facilitates P cycling, but the strategy may be of limited benefit in low-rainfall areas that do not have the capacity to produce large biomass inputs. Evidence that organic or low-input systems naturally increase the numbers and diversity of soil organisms is sparse and published studies from Australian systems suggest that P nutrition is not enhanced. However, seed and soil microbial inoculants to facilitate improved P uptake have been developed and are currently being field tested in Australia. Progress in selection and breeding for cereal genotypes that are more P efficient and other plant genotypes that can use less labile P sources, is gaining momentum but still remains a long-term prospect, and may involve genetic modification which will not be acceptable for organic systems.
  • Authors:
    • Vanderlinden, K.
    • Murillo, J. M.
    • Madejon, E.
    • Lopez-Garrido, R.
    • Melero, S.
    • Ordonez, R.
    • Moreno, F.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 133
  • Issue: 1-2
  • Year: 2009
  • Summary: Long-term field experiments can provide relevant information regarding soil organic carbon sequestration under different soil tillage systems. Especially, conservation tillage (CT) has been proved to be a practice that highly contributes to improve soil quality. For that reason, the study of soil quality indicators, such as organic fractions, are useful tools to assess changes caused by different soil tillage systems in long-term field experiments. We evaluated long-term effects of conservation tillage on soil carbon fractions and biological properties in a sandy clay loam Entisol (soil A) and in a clay Vertisol (soil B) located in semi-arid SW Spain. Cereal-sunflower-legume rotations under rainfed conditions were used in both soils in which conservation tillage (CT) was compared to traditional tillage (TT). Soil samples were collected at three depths (0-5, 5-10 and 10-20 cm) four months after sowing a pea crop ( Pisum arvense L.) in the Entisol and a wheat crop ( Triticum aestivum L.) in the Vertisol. Labile fractions of the total organic carbon (TOC) were determined as active carbon (AC) and water soluble carbon (WSC). Biological status was evaluated using soil microbial biomass carbon (MBC) and enzymatic activities [dehydrogenase activity (DHA), o-diphenol oxidase activity (Dphox), and beta-glucosidase activity (beta-glu)]. As a rule, the contents of AC, WSC, MBC, beta-glu and Dphox in soil A and contents of TOC, AC and DHA in soil B were higher in CT than in TT, at the 0-5 cm depth. In both soils, the studied parameters decreased with depth under both tillage treatments (TT and CT). Values of AC, TOC, MBC and beta-glu were positively correlated with each other ( p
  • Authors:
    • Cornish, P. S.
  • Source: Crop & Pasture Science
  • Volume: 60
  • Issue: 2
  • Year: 2009
  • Summary: This special issue, which is largely based on the workshop organized by the Rural Industries Research and Development Corporation, contains 9 papers on the sustainable management of phosphorus (P) in Australian farms. Topics covered include: improving the P efficiency of organic farming without inputs of soluble P fertilizers; P management on extensive organic and low-input farms; options for increasing the biological cycling of P in low-input and organic agricultural systems; plant mechanisms to optimize access to soil P; the potential to improve root access to P and the role of non-symbiotic microbial inoculants in the rhizosphere; new fertilizer options for managing P for organic and low-input farming systems; agronomic management options for P in Australian dryland organic and low-input cropping systems; P uptake in faba bean, field pea, and maize cultivars from different sources; and improving plant uptake of soil P, and reducing dependency on input of P fertilizer.
  • Authors:
    • Scialabba, N.
    • Hepperly, P.
    • Fließbach, A.
    • Niggli, U.
  • Year: 2009
  • Authors:
    • Florio, G.
    • Brigi, A.
    • Sandrini, S.
    • Bona, S.
    • Coletto, L.
    • Sambo, P.
  • Source: Proceedings of the Conference on integrated assessment of agriculture and sustainable development: Setting the Agenda for Science and Policy (AgSAP 2009), Hotel Zuiderduin, Egmond aan Zee, The Netherlands, 10-12 March 2009
  • Year: 2009
  • Authors:
    • Sanjay, K.
    • Sharma, S.
    • Kaushik, V.
  • Source: Journal of Environmental Research and Development
  • Volume: 4
  • Issue: 4
  • Year: 2009
  • Summary: Suitable to environment or eco-friendly means not harmful to our system of environment i.e. not harmful to land, air etc. Presently, due to agriculture a lot of pollutants are added day by day in our environment. Because of these pollutants, the soil fertility is decreasing, the fear of disease in living beings are increasing, a lot of poisonous chemicals and gases prevails in the environment. There is a great need to the use of such a cropping system which is suitable to environment i.e Eco-friendly system of cropping. The Eco-friendliness of cropping system may be viewed from two different angles i.e systems which help in soil and water conservation and system which reduce the use of pesticides, insecticides, herbicides, organic fertilizers. As far as the pesticides use is concerned at national level, it is a still for below the alarming proportions. Inclusion of such crops in the cropping systems in problem areas can play a significant role in minimizing the use of agro-chemicals in the crop production. Insecticides or fungicides use can also be minimized to a considerable extent through cropping system approach. It has been reported that sorghum ear-head fly damage is extremely rare where pigeon pea is planted in alternate rows. Intercropping of coriander in autumn planted sugarcane prevent top borer in sugarcane Sorghum helepense ( L) pers (Tohangen grass) becomes predominant weed in continuous maize cultivation but can be controlled by rotating with cotton. Adoption of sugarcane wheat system in place of rice-wheat decreases philaries minor infestation to almost negligible level which is otherwise not achieved through herbicides. In maize-potato cropping system raising of pearl millet for green fodder or sesamum for green manure during summer was also found advantageous in reducing Cyprus rotundas in succeeding crop of maize and potato. Position of ground water owing to leaching of nitrates is a selectively new concern in India. Because usage of N-fertilizer is low in India, nitrate is not likely to pose serious problems in most farming situations. Choice of appropriate system and management practices helped minimizing nitrate leaching besides improving N-use efficiency.
  • Authors:
    • Matsumoto, T.
    • Taeb, M.
    • Malley, Z.
  • Source: Environment Development and Sustainability
  • Volume: 11
  • Issue: 1
  • Year: 2009
  • Summary: Sustainable agricultural development is a necessity for sustainable economic growth and social development in Africa. Sustainable agriculture largely depends on how effective natural and environmental resources are managed and utilized; it also depends on the security of continuous access to such resources. This research was aimed to look into trends in agricultural productivity, examine the persistence of the environmental insecurity, analyze the relationship between the two, and explore their links to the national development policies. The results are discussed in the context of relevance to national development policies and their implications on the sustainability of agriculture and rural livelihoods security. Literature survey, records collection from the stakeholders, village level participatory assessments (PAs), observations and questionnaire survey were tools used for data collection. The study shows significant ( P