• Authors:
    • Lal, R.
    • Blanco-Canqui, H.
  • Source: Soil Science Society of America Journal
  • Volume: 73
  • Issue: 2
  • Year: 2009
  • Summary: Franzluebbers (2009) is right about the need for a more intensive soil sampling, "repeated sampling with time,"and "stratified sampling" as well as for the use of multiple fields and collection of larger number of pseudoreplicates to overcome the high field variability in soil organic carbon (SOC) pools within each Major Land Resource Area (MLRA). The selected fields were representative of each MLRA in terms of soil type, slope, and management, but it is correct that a single soil would not capture all the variability in soil and management for the whole MLRA. This study was not intended to relate the data from the single soil to the whole MLRA but rather to emphasize the differences in SOC sequestration rates among the three management systems within each soil.
  • Authors:
    • Azevedo, W.
    • Pereira, H.
    • Reis, E.
    • Souza, E.
    • Carneiro, M.
  • Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
  • Volume: 33
  • Issue: 1
  • Year: 2009
  • Summary: This study investigated the effects of tillage systems and soil use on the physical, chemical and biological properties of a clayey dystrophic Red Latosol (Oxisol) and a sandy Neosol (Entisol). The treatments for the Oxisol consisted of: native savanna, pasture, conventional tillage, no-tillage with turnip and with forage sorghum as cover crop. For the Entisol: native savanna, native pasture, integrated crop-livestock, cultivated pasture, no-tillage with soyabean and maize in the summer. Soil samples were collected from a depth of 0-10 cm, in a clayey dystrophic Oxisol and a sandy Entisol in a savanna ecosystem, near the Parque Nacional das Emas in Goias, Brazil. Treatments were arranged in a completely randomized design, in 5 plots of 150 m 2, where 10 sub-samples were collected randomly. Chemical, physical and biological analyses were carried out at a soil laboratory. In the Entisol, tillage influenced the soil density, total pore volume, macroporosity and penetration resistance. In the Oxisol, tillage induced variations in soil bulk density, macroporosity and penetration resistance. Small variations in chemical properties were observed in both soils, with higher potential acidity and lower exchangeable cation and phosphorus concentrations. The soil biological properties were influenced by tillage, and were most affected in systems with more anthropic action. In the canonical data analysis the greater weighting coefficient of the physical properties in the canonic variables demonstrated that these were the least important. The contribution of the separate soil properties to evaluate soil quality was minor, but the most sustainable management systems could be defined by multivariate analysis.
  • Authors:
    • Idoko, J.
    • Egbe, O.
  • Source: Agro-Science
  • Volume: 8
  • Issue: 2
  • Year: 2009
  • Summary: Field experiments were conducted at the National Root Crops Research Institute sub-station, Otobi, in 2006 and 2007 to assess the suitability of improved sweet potato varieties for intercropping with pigeonpea and also to determine the planting pattern and the productivity of the intercropping system. Intercropping decreased total fresh root and saleable root yields of sweet potato when mixed or row-intercropped with pigeonpea. All intercropping combinations of sweet potato varieties and pigeonpea had land equivalent ratio above 1.0, except intercropping with WA Gabolige, signifying high intercrop advantages. TIS 87/0087 produced the highest total fresh root and saleable root yields in both cropping systems, irrespective of the planting pattern used. TIS 2532.O.P.1.13 and TIS 86/00356 sweet potato varieties had comparable yields with TIS 87/0087 in both cropping systems. Pigeonpea was the more competitive component of the intercrop. Farmers showed willingness to adopt the sweet potato+pigeonpea intercropping.
  • Authors:
    • Joergensen, R.
    • Formowitz, B.
    • Buerkert, A.
  • Source: Plant and Soil
  • Volume: 325
  • Issue: 1/2
  • Year: 2009
  • Summary: Many microbial turnover processes in acidic sandy subtropical soils are still poorly understood. In a 59-day pot and a 189-day laboratory incubation experiment with two West African continuous cereal soils, the effects of 2 mg g -1 root residues were investigated on growth of sorghum seedlings, soil microbial biomass and activity indices, using cowpea, groundnut, pearl millet, maize and sorghum. The effects of root residues were compared with mineral P or mineral P+N treatments and with a non-fertilized control treatment. On the Alfisol (Fada, Burkina Faso), shoot dry mass was always significantly higher than on the Ultisol (Koukombo, Togo). Highest shoot dry mass was observed after application of mineral P+N on the Alfisol and after mineral P alone on the Ultisol. The application of legume root residues led to small and non-significant increases in dry mass production compared to the non-amended control, whereas the application of cereal root residues led to a decline, regardless of their origin (millet, maize or sorghum). Contents of microbial biomass C, microbial biomass N and ergosterol were 75 to 100% higher in the Alfisol than in the Ultisol, while ATP was only 36% higher. Organic amendments increased ergosterol concentrations by up to 145% compared to the control and mineral P application. Microbial biomass C and microbial biomass N increased by up to 50% after application of root residues, but ATP only up to 20%. After application of legume root residues, cumulative CO 2 production was similar in both soils with an average of 370 g CO 2-C g -1 over 189 days. After application of cereal root residues, cumulative CO 2 production was higher in the Alfisol (530 g g -1) than in the Ultisol (445 g g) over 189 days.
  • 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
  • Authors:
    • Cargnelutti Filho, A.
    • Assis, R.
    • Procopio, S.
    • Monteiro, F.
    • Pires, F.
    • Pacheco, L.
    • Carmo, M.
    • Petter, F.
  • Source: Planta Daninha
  • Volume: 27
  • Issue: 3
  • Year: 2009
  • Summary: The objective of this experiment was to evaluate the efficiency of soybean oversowing, using cover crops, in reducing weed emergence and its reflections on the productivity of the soybean cultivated in the following season. The experiment was arranged in a randomized block design, in split-plot, with four replications. The soybean was sown four times: (1) 10/27/2005, (2) 11/10/2005, (3) 11/24/2005 and (4) 12/14/2005, under a no-tillage system, corresponding to four times of soybean oversowing, occurring respectively, on 01/30/2006; (b) 02/13/2006; (c) 02/22/2006; and (d) 03/14/2006. Six cover crops were evaluated [ Brachiaria brizantha, B. ruziziensis, B. decumbes, Eleusine coracana, Pennisetum glaucum and cover crop-sorghum hybrid ( Sorghum bicolor cv. Bicolor) with Sudan-grass ( Sorghum bicolor cv. Sudanense)] and untreated (spontaneous vegetation) in four oversowing times. Oversowing was performed manually when the soybean reached the R 7 stadium (beginning of defoliation during physiological maturation), in each of the four sowing times of the 2005/06 soybean crop. The first cover crop desiccation was carried oat on 10/23/2006. After 20 days, the second desiccation was applied, followed by soybean sowing, cultivar MSOY 6101, early cycle, 0.45 m spaced, aimed at a population of 500.000 plants ha -1. Soybean oversowing, especially when using brachiaria, showed to be an important tool for the integrated management of weed plants, since it provides a larger biomass contribution and soil cover and sustainability to no-till systems in the cerrado.
  • Authors:
    • Gajbhiye, K. S.
    • Ray, S. K.
    • Prasad, J.
    • Singh, S. R.
  • Source: Agropedology
  • Volume: 19
  • Issue: 2
  • Year: 2009
  • Summary: Detailed soil survey of Selsura KVK research farm of Dr. P.D.K.V., Akola in Wardha district, Maharashtra was carried out using 1:6000 scale cadastral map. There were nine soil series and thirteen mapping units. The soils were very dark gray to very dark grayish brown in hue 10YR, calcareous and clayey but differed in depth and are classified under Entisols, Inceptisols and Vertisols. In general, pH (8.0-9.2) increased with depth whereas reverse trend was observed for organic carbon. Soils of Selsura-1 are prone to sodicity problems. DTPA-Zn and Fe were deficient in these soils but DPTA-Mn and Cu were optimum. The mapping units were grouped under II to IV land capability classes and 2 to 4 land irrigability classes. Except soils of Selsura-7 series (very shallow), others are moderately or marginally suitable for one or more commonly growing rainfed kharif crops viz. cotton, sorghum, pigeonpea, soybean and groundnut.
  • Authors:
    • Jajoo, S. B.
    • Kamble, P. O.
    • Shinde, K. J.
  • Source: Green Farming
  • Volume: 13
  • Issue: 1 (Special 1)
  • Year: 2009
  • Summary: A study was conducted to suggest optimal resources allocation for crop plan to net benefit maximization using linear programming model for Akola district in Maharashtra state. Resources management plan was developed with allocation of land and water for different crop activities to maximize the net return taking into account land capability classification, availability of water in different season, crop water requirements, food requirement and affinity towards the crops of the peoples in district. In existing crop plan during kharif season major area is under cotton (43.45%) followed by jowar (17%) whereas in proposed optimal crop plan without capital constraints major area was allocated under soybean (30%), cotton+tur (20%) of the total cultivable area of the district. In rabi major area in existing is under gram (5.2%) whereas in proposed plan area is allocated to wheat (20%), gram (20%). In existing summer area is 0.18% and annual was nil whereas in proposed plan is 3% and 4.13% respectively. In existing gross investment and net return per hectare was 10341 and 5203 Rs/ha whereas in proposed plan is 14864 and 8833 Rs/ha. In proposed plan net return per hectare increases by Rs. 3630.
  • 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.