• Authors:
    • de Cara Garcia, M.
    • Roubtsova, T.
    • Antonio Lopez-Perez, J.
    • Ploeg, Antoon
  • Source: Journal of Nematology
  • Volume: 42
  • Issue: 2
  • Year: 2010
  • Summary: Broccoli (Brassica oleracea), carrot (Daucus carob), marigold (Tagetes patula), nematode-resistant tomato (Solanum lycopersicum), and strawberry (Fragaria ananassa) were grown for three years during the winter in a root-knot nematode (Meloidogyne incognita) infested field in Southern California. Each year in the spring, the tops of all crops were shredded and incorporated in the soil. Amendment with poultry litter was included as a sub-treatment. The soil was then covered with clear plastic for six weeks and M. incognita:susceptible tomato was grown during the summer season. Plastic tarping raised the average soil temperature at 13 cm depth by 7 degrees C. The different winter-grown crops or the poultry litter did not affect M. incognita soil population levels. However, root galling on summer tomato was reduced by 36%, and tomato yields increased by 19% after incorporating broccoli compared to the fallow control. This crop also produced the highest amount of biomass of the five winter-grown crops. Over the three-year trial period, poultry litter increased tomato yields, but did not affect root galling caused by M. incognita. We conclude that cultivation followed by soil incorporation of broccoli reduced M. incognita damage to tomato. This effect is possibly due to delaying or preventing a portion of the nematodes to reach the host roots. We also observed that M. incognita populations did not increase under a host crop during the cool season when soil temperatures remained low (< 18 degrees C).
  • 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:
    • Miquelluti, D. J.
    • Oliveira, O. L. P. de
    • Ferreira, E. Z.
    • Nohatto, M. A.
    • Mafra, A. L.
    • Rosa, J. D.
    • Cassol, P. C.
    • Medeiros, J. C.
  • Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
  • Volume: 33
  • Issue: 1
  • Year: 2009
  • Summary: This study was conducted to evaluate the effect of phytomass management forms of different cover crop species on soil chemical properties related to organic matter, nutrient availability, and on grapevine yields. The experiment was carried out in Embrapa Uva e Vinho, in Bento Goncalves, Rio Grande do Sul, in Southern Brazil, on a Haplic Cambisol, in a vineyard established in 1989, using White and Rose Niagara grape in a horizontal overhead trelling system. The treatments established in 2002 were three cover crops: spontaneous native species, black oat ( Avena nuda), and a mixture of white clover ( Trifolium repens) + red clover ( Trifolium pratense) + annual ryegrass ( Lolium multiflorum); and two management systems: desiccation by herbicide spraying and mechanical mowing, performed each autumn prior to cover crop resowing. The experiment had a completely randomized block design, with three replications. Soil acidity and nutrient contents were little influenced by the plant cover. In comparison with the mowed management, herbicide application increased exchangeable Ca and Mg, extracted P, and organic C levels in the soil. The grape yield in the seasons 2004 and 2006 was low in view to the cultivar potential, probably affect by climatic limitations, but was higher when black oat was used as plant cover instead of the mixture of plant covers.
  • Authors:
    • Horwath, W.
    • Kallenbach, C.
    • Assa, J.
    • Burger, M.
  • Year: 2009
  • Authors:
    • Zhou, X.
    • Wu, F.
  • Source: Acta Pedologica Sinica
  • Volume: 46
  • Issue: 5
  • Year: 2009
  • Summary: Plenty of reports about effects of intercropping improving yield and reducing disease incidence are available, but little was reported about the mechanism of the effects. RAPD and T-RFLP methods were used to study effects of intercropping of cucumber with wheat, vicia villosa and clover, individually, on cucumber disease indexes, cucumber rhizosphere soil microbial community diversity and yield. Results showed that intercropping of cucumber with wheat and vicia villosa increased soil microbial community diversity in cucumber rhizosphere, and the effect of the latter was the most prominent. All intercropping modes increased cucumber yield significantly ( p
  • Authors:
    • Takle, S. R.
    • Kunte, A. P.
    • Bhise, V. B.
  • Source: Resource-use efficiency in irrigated Indian agriculture 2009
  • Year: 2009
  • Summary: The present study was conducted on irrigated farms to study the resource use efficiency and returns to scale in the command area of Penganga irrigation project. A sample of 310 farmers was scientifically chosen out of which 94 were from head-reach, 100 from middle reach and 116 belonged the tail reach location of the command area and the study was conducted during the agricultural year 2004-05. The study was confined to three foodgrains, i.e. green gram, kharif Jowar and Wheat, and four cash crops, viz., cotton, sugarcane, banana and soyabean. A Cobb-Douglas production function was fitted to estimate the resource-use efficiency and returns to scale in the crop production in irrigated Indian agriculture. The study observed that some of the resources have been either under-utilised or over-utilised; hence to increase the agricultural production all the resources should be used efficiently. Along with the efficient use of all the resources, new technology should also be adopted for increasing productivity. The ratio of marginal value product to factor cost for some resources (human labour, bullock labour, fertilisers and seeds) was found to be more than one, indicating the operation of increasing factors returns. In general for cash crops, the study suggests to increase the use of resources viz. bullock labour, working capital, seeds and irrigation so as to increase the production of the cultivated cash crops.
  • Authors:
    • Monteiro, J. E. B. A.
  • Source: Agrometeorologia dos cultivos: o fator meteorológico na produção agrícola
  • Year: 2009
  • Summary: This book brings together a broad base of information on 32 major Brazilian agricultural crops and their relations with climate. The focus of the book is not on the methodologies and applications of agrometeorology per se, but rather restricts its focus to crops and traits that determine yield as a function of the environment. The crops included are rice, castor oil, sunflowers, pineapples, soyabeans, triticale, maize, potatoes, barley, peanuts, oats, onions, canola, wheat, cotton, beans, sugarcane, Pinus, black wattle ( Acacia mearnsii), tropical and temperate grapes, coconuts, citrus, bananas, sisal, cocoa, coffee, apples, Jatropha, Eucalyptus and the fodder plants Cynodon, Brachiaria and Panicum. The contents of the book are divided into three main parts, I. Introduction, II. Temporary crops and III. Permanent crops, with each chapter within parts II and III dedicated to a particular crop, and covering: (1) the main features of farming and phenology; (2) agrometeorological productivity constraints - water availability, temperature, solar radiation, photoperiod and wind; and (3) adverse events - hail and rainstorms, droughts and dry spells, winds and gales, frost, and too much rain and over-prolonged drought. The book was organized by the National Institute of Meteorology and had the collaboration of 105 researchers from 37 Brazilian institutions (federal and state), research centres, institutes and universities.
  • Authors:
    • Pérez, R.
    • Ayuso, J. L.
    • Taguas, E. V.
    • Yuan, Y.
    • Peña, A.
  • Source: Earth Surface Processes and Landforms
  • Volume: 34
  • Issue: 5
  • Year: 2009
  • Summary: Despite the high risk of erosion in olive Orchards located in mountainous areas in Spain, little research has been carried out to account for the complexity and interaction of the natural processes of runoff and soil erosion on the catchment scale or small catchment scale. In this Study, a microcatchment of 6.7 ha in a mountainous area under no-tillage farming with hare soil was Set Up to record runoff and sediment. Soil erosion and runoff patterns were monitored Over a two-year period. Totally events were observed. The data were analysed, and then Used to calibrate the, AnnAGNPS model, which allowed Lis to complete the data period and describe the hydrological and erosive behaviour on a monthly and annual basis. A high variability in catchment responses was observed, due to differences in the storms and to the effect of the surface Soil moisture content. Maximum intensities of 10 and 30 min determined the final runoff Values while the total sediment leads were dependent on the rainfall depth. The impact of management on the reduction of porosity can explain the relationship between runoff and intensity in the microcatchment. However, the impact of the spatial scale meant that the transport of sediment required substantial rainfall depths to ensure a Continuous flew front the hillslopes. The results of the calibration (E > 0.60 and r > 0.75) on the event and monthly scale confirmed the applicability of AnnAGNPS to predict runoff and erosion in the microcatchment. The predicted average runoff coefficient was 3.3% for the study period and the total average Sediment loads, 1.3 Mg/ha/yr. Despite these low Values, the model Simulation Showed that much larger runoff coefficients and soil losses can be expected for periods with several consecutive years in which the annual rainfall depth was over 500 mm). The use of cover is recommended to prevent the high levels of erosion associated with these conditions. Copyright (C) 2009 John Wiley & Sons, Ltd,
  • Authors:
    • Durán Zuazo, V. H.
    • Rodríguez Pleguezuelo, C. R.
    • Arroyo Panadero, L.
    • Martínez Raya, A.
    • Francia Martínez, J. R.
    • Cárceles Rodríguez, B.
  • Source: Pedosphere
  • Volume: 19
  • Issue: 4
  • Year: 2009
  • Summary: Sloping and mountainous olive production systems are widespread, occupying large parts of the Mediterranean landscape prone to water erosion. Soil erosion, runoff, and soil water content patterns over a three-year period were monitored in erosion plots on a mountainside with rainfed olive (Olea europaea cv. Picual) trees under: 1) non-tillage with barley strips of 4 m width (BS); 2) non-tillage with native vegetation strips of 4 m width (NVS); and 3) non-tillage without plant strips (NT). The erosion plots, located in Lanjaron (Granada, south-eastern Spain), on a 30% slope, were 192 m(2) in area. For assessing soil water dynamics in real-time and near-continuous soil water content measurements, multisensor capacitance probes were installed in the middle of plant strips and beneath the olive tree at five soil depths (10, 20, 30, 50, and 100 cm). The highest erosion and runoff rates were measured under NT, with a mean of 17.3 Mg ha(-1) year(-1) and 140.0 mm year(-1), respectively, over the entire study period. The BS and NVS with respect to the NT reduced erosion by 71% and 59% and runoff by 95% and 94%, respectively. In general, greater available soil water content was found under BS than NVS and NT, especially beneath the olive tree canopies. These results supported the recommendation of non-tillage with barley strips in order to reduce erosion and to preserve soil water for trees in traditional mountainous olive-producing areas, where orchards cover vast tracts of land.
  • Authors:
    • Vicente, M. C. de
    • Andersson, M. S.
  • Source: book
  • Year: 2009
  • Summary: This comprehensive volume provides the scientific basis for assessing the likelihood of gene flow between twenty important crops and their wild relatives. The crops discussed include both major staples and minor crops that are nonetheless critical to food security, including bananas and plantain, barley, canola, cassava, chickpeas, common beans, cotton, cowpeas, finger millet, maize, oat, peanuts or groundnuts, pearl millet, pigeonpeas, potatoes, rice, sorghum, soyabeans, sweet potatoes, and wheat. Each chapter is devoted to one of the crops and details crop-specific information as well as relevant factors for assessing the probability of gene flow. The crop-specific reviews provide insights into the possible ecological implications of gene escape. For each crop, a full-colour world map shows the modelled distributions of crops and wild relatives. These maps offer readers, at a glance, a means of evaluating areas of possible gene flow. The authors classify the areas of overlap into three "gene-flow categories" with respect to the possibility of genetic exchange. The systematic, unbiased findings provided here will promote well-informed decision making and the conservation of wild relatives of crops. This book is particularly relevant to agriculture in developing countries, where most crop biodiversity is found and where current knowledge on biodiversity conservation is limited. Given the ecological concerns associated with genetically modified crops, this reference is an essential tool for everyone working to feed a growing world population while preserving crop biodiversity.