• Authors:
    • Fernandes Cruvinel, E.
    • Bustamante, M.
    • Zepp, R.
    • Kozovits, A.
  • Source: AGRICULTURE ECOSYSTEMS & ENVIRONMENT
  • Volume: 144
  • Issue: 1
  • Year: 2011
  • Summary: In the last 40 years, a large area of savanna vegetation in Central Brazil (Cerrado) has been converted to agriculture, with intensive use of fertilizers, irrigation and management practices. Currently, the Cerrado is the main region for beef and grain production in Brazil. However, the consequences of these agricultural practices on NO, N2O and CO2 emissions from soil to atmosphere are still poorly investigated. The objectives of this study were to quantify soil emissions of NO-N, N2O-N and CO2-C in different no-till cultivation systems in comparison with native savanna vegetation. The agricultural areas included: (a) the maize and Brachiaria ruzizienses intercropping system followed by irrigated bean in rotation; (b) soybean followed by natural fallow; and (c) cotton planting over B. ruzizienses straw. The study was performed from August 2003 to October 2005 and fluxes were measured before and after planting, after fertilizations, during the growing season, before and after harvesting. NO-N fluxes in the soybean field were similar to those measured in the native vegetation. In the cornfield, higher NO-N fluxes were measured before planting than after planting and pulses were observed after broadcast fertilizations. During Brachiaria cultivation NO-N fluxes were lower than in native vegetation. In the irrigated area (bean cultivation), NO-N fluxes were also significantly higher after broadcast fertilizations. Most of the soil N2O-N fluxes measured under cultivated and native vegetation were very low (<0.6 ng N2O-N cm(-2) h(-1)) except during bean cultivation when N2O-N fluxes increased after the first and second broadcast fertilization with irrigation and during nodule senescence in the soybean field. Soil respiration values from the soybean field were similar to those in native vegetation. The CO2-C fluxes during cultivation of maize and irrigated bean were twice as high as in the native vegetation. During bean cultivation with irrigation, an increase in CO2-C fluxes was observed after broadcast fertilization followed by a decrease after the harvest. Significantly lower soil C stocks (0-30cm depth) were determined under no-tillage agricultural systems in comparison with the stocks under savanna vegetation. Fertilizer-induced emission factors of N oxides calculated from the data were lower than those indicated by the IPCC as default.
  • Authors:
    • Srivastava, A. K.
    • Panigrahi, P.
  • Source: Indian Journal of Soil Conservation
  • Volume: 39
  • Issue: 2
  • Year: 2011
  • Summary: A field experiment was conducted during 2006-08 to assess the response of deficit irrigation (DI) in 16 year old drip-irrigated Nagpur mandarin ( Citrus reticulata) trees budded on Rough lemon ( Citrus jambhiri L.) root stock at Nagpur, Maharashtra. The DI regimes imposed were at 30, 50, and 70% of Full irrigation (FI) and compared with FI (control). The annual increase in vegetative growth parameters (tree height and canopy volume) of trees under FI was found to be superior over DI treatments. The soil moisture status measured at 30 cm, 45 cm and 60 cm depths showed that the mean monthly soil moisture content was significantly affected at 30 cm depth, with highest magnitude (27.6-30.7%, v/v) under FI. Leaf nutrients (N, P, K, Fe, Mn, Cu, and Zn) analysis indicates that FI registered the maximum leaf N, K, and Fe, followed by 70% FI. The highest fruit yield (14.10 t ha -1) recorded under FI was at par with DI at 70% FI (13.35 t ha -1). More number and smaller size of fruits were recorded in FI as compared to DI at 70% FI. However, DI at 70% FI produced 36% higher water productivity with superior quality fruits (more fruit weight, higher TSS and lower acidity) over FI.
  • Authors:
    • Srivastava, A. K.
    • Panigrahi, P.
  • Source: Journal of Agricultural Engineering
  • Volume: 48
  • Issue: 3
  • Year: 2011
  • Summary: A field experiment was conducted during 2006-2008 to optimize the combined use of irrigation and fertilizers through drip irrigation for bearing Nagpur mandarin ( Citrus reticulate Blanco) plants at Nagpur, Maharashtra, India. The irrigation at 50% (I 1), 75% (I 2), and 100% (I 3) of daily class-A pan evaporation rate (Ep) along with 25% (F 1), 50% (F 2) and 75% (F 3) of recommended dose of fertilizers (RDF: 600 g N+100 g P 2O 5+200 g K 2O) were applied through drip emitters to 12 year old mandarin plants. For comparison, band placement of fertilizer (BPF) at 100% RDF under basin irrigation (BI) was taken as control. All the irrigation and fertilizer treatments (except I 1F 1) imposed through drip system produced higher plant growth and fruit yield, with better quality fruits over BI with BPF. The highest fruit yield (16.03 t.ha -1) with superior quality fruits (41.8% juice content, 10.2degreesBrix TSS and 0.82% acidity) was recorded under I 2F 3. Leaf nutrients (N, P, K, Fe, Cu, Zn and Mn) analysis indicated that I 2F 3 registered significantly higher leaf-N (2.15%) and K (1.87%), whereas I 3F 3 produced higher P (0.11%) and Fe (113.99 ppm) as compared with BI with BPF (1.98% N, 0.081% P, 1.64% K, and 93.52 ppm Fe). The study demonstrated that the application of optimum quantity of water and fertilizers (I 2F 3) through drip irrigation saved 50% and 25% of water and fertilizers, respectively, besides producing 60% higher fruit yield with better quality fruits over BI with BPF.
  • Authors:
    • Chauhan, S. N.
    • Kumari, P. R. V.
    • Tayade, A. S.
    • Reddy, A. R.
    • Thakare, S. K.
    • Majumdar, G.
    • Raju, A. R.
    • Mahalle, P. S.
    • Katore, J. R.
  • Source: Journal of Cotton Research and Development
  • Volume: 25
  • Issue: 2
  • Year: 2011
  • Summary: Series of field trials were conducted during 1987-2010 at Central Institute for Cotton Research, Nagpur indicated that in shallow, medium and deep soils, it was estimated to collect 150, 300 and 350 M 3 of runoff water/ha in experimental ponds (200 M 3) at down stream by September end, 56-82 per cent of the pond capacity, was stored. The recycling of this runoff water through supplemental irrigation during 1987-1993, improved additional seed cotton yield by 136, 290 and 387 kg/ha or 20, 28 and 26 per cent over rainfed cotton LRA 5166 in shallow, medium and deep soils respectively. The supplemental irrigations improved WUE by 34, 73 and 97 kg/ha cm respectively in shallow, medium and deep soils. Experimental pond (200 M 3) size presently advocated, were not accepted by the farmers as they were economically non viable at field scale, but these can be helpful in improving the recharge of existing gravitational wells. Two supplemental irrigations at flowering stage along with deficient micronutrients improved seed cotton yields of 25-30 per cent higher in shallow and medium deep soils, respectively during 2002-2007 in NHH 44 non Bt hybrid cotton. It is difficult to provide life saving irrigations from farm ponds in first fortnight of July to seedling droughts. Large farm ponds at community levels can solve this problem of seedling droughts from the recharge of previous year in underground aquifers besides recharging the drinking water wells for summer shortages with 2-3 years of breakeven under multiple uses of water. Terminal droughts of August can overcome by supplemental irrigations from farm ponds of 10 ha catchment with a breakeven of 12 years. Bt hybrid cotton responded for two supplemental irrigations from harvested runoff water at seedling/terminal droughts in July (12-47% runoff) or in mid September (23-80% runoff) @ 750 kg/ha seed cotton yield in vertisols.
  • Authors:
    • Adetunji, M.
    • Makinde, E.
    • Akande, M.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 42
  • Issue: 9
  • Year: 2011
  • Summary: Field trials were conducted at the Institute of Agricultural Research and Training Ibadan in 2000 and 2001 cropping seasons to evaluate the efficiency of some phosphorus (P) sources, rates, and frequency of application on grain yields of maize and cowpea grown sequentially. The experiment was laid out in a split-split plot arrangement using randomized complete block design, with three replications. The main plot was frequency of fertilizer application (seasonal and annual). Source of P [single superphosphate (SSP: 18% P 2O 5)]; Ogun rock phosphate (OPR: 20.21% P 2O 5), and crystallizer super (CS: 31.4% P 2O 5) constituted the subplots. The P rates (0, 20, 40, and 60 kg P ha -1) were the sub-subplots. An early maize cropping followed by a late-season cowpea was the sequential cropping, while an early maize followed by a late-season maize was the continuous cropping. The croppings were repeated the second year. Frequency of P application and source of P were significantly different while rates of application were not. Maize and cowpea grain yields from the control treatment were significantly less than yields from P-treated plots. Maize grain yields were slightly greater in plots alternated with cowpea, compared to continuous maize. Relative agronomic efficiency (RAE) values of OPR and CS were 67% and 75%, respectively, in annual application and 140% and 134% in seasonal applications, respectively, in 2000. In 2001, the trend was almost similar to 2000 except that there was a decline in RAE values of cowpea. Each Naira invested in the annual application returned about Naira 3.12 while about Naira 2.13 was returned with the seasonal application (Naira 125.00 is the equivalent of USD$1.00). The OPR and CS can serve as alternatives to water-soluble sources such as SSP.
  • Authors:
    • Ferrari, S.
    • Picoli, P.
    • Lazarini, E.
    • Barbosa, C.
  • Source: Cientifica (Jaboticabal)
  • Volume: 39
  • Issue: 1/2
  • Year: 2011
  • Summary: The objective of this study was to evaluate the straw effect of four cover crops [grain sorghum ( Sorghum bicolor L. Moench), sun hemp ( Crotalaria juncea L.), pearl millet ( Penisetum americanum L.), and brachiaria ( Brachiaria brizantha cv. Marandu)] sown at two different times and a fallow area and its effects on soybean cultivated in succession in a no tillage system. The study was carried out from march/08 to april/09 in the experimental farm of the College of Engineering, a unit of the Universidade Estadual Paulista (UNESP), located in Selviria, a county of the state of Mato Grosso do Sul, (51degrees22′W and 20degrees22′S, with 335 m altitude), Brazil, in an Oxisol. The treatments consisted in the sowing of the four cover crops on March 27 and April 23 of 2008 and in the use of a fallow area. The experiment was set in the field according to a randomized complete block design with eight repetitions. Forage crops (sunhemp and B. brizantha) sown in two seasons do not change the soybean yield. Soybean yield on sorghum and millet sown in March was higher than that observed for the same crops sown in April. The grasses used are shown as a viable option for the production of dry matter for soybean sown in March.
  • Authors:
    • Ward, J.
    • King, D.
    • Bryan, B.
  • Source: Ecological Indicators
  • Volume: 11
  • Issue: 1
  • Year: 2011
  • Summary: On-farm actions to better manage natural resources often involve an opportunity cost associated with foregone agricultural production. Spatial information on agricultural opportunity costs is a key indicator that has been demonstrated to increase the cost-effectiveness of environmental investment through spatial targeting. In this paper we develop a method for calculating expected profit as a more robust spatial measure of economic rent accruing from agricultural land and indicator of opportunity cost for use in landscape and planning for natural resource management. We apply this method to the Lower Murray region in southern Australia. Agricultural profit is calculated for three farming system phases (cereals, legumes, and grazing) by census zones based on agricultural statistics and cost of production information within a GIS environment. Zonal profit layers are smoothed using pycnophylactic (mass preserving) interpolation. Farming system rotations are quantified as a set of continuous spatial probability layers for each phase using a moving window kernel density technique based on existing land use data and these probability layers are used in a weighted allocation of expected profit across the landscape. The expected profit layer provides a high spatial resolution description of opportunity costs associated with natural resource management over the Lower Murray region suitable for input into systematic landscape planning analyses. Validation of the opportunity cost layer by field survey identified both random and systematic error. Interpretation of systematic error highlighted the need to augment pycnophylactic interpolation techniques with consideration of covariates of profit such as rainfall for better estimation in areas with high profit gradients.
  • Authors:
    • Damiescu, L.
    • Trif, A.
    • Galbenu-Morvay, P.
    • Simion, G.
  • Source: Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Agriculture
  • Volume: 68
  • Issue: 2
  • Year: 2011
  • Summary: T-2 toxin is a secondary metabolite mainly produced by fungi belonging to the genus Fusarium, principally by F. sporotrichioides, F. poae, F. equiseti and F. acuminatum which are common contaminants in staple foods of cereal origin such as oats, barley, rice, maize, wheat etc., and different by-products. T-2 toxin belongs to the closely related sesquiterpenoid family of thrichotecenes and is a potent inhibitor of protein synthesis. Its main effects are usually observed in the immune system which has strong impact on the health of both humans and animals. Although is one of the most toxic type A trichothecene, T-2 toxin occurrence data is scarce and European Commission (EC) legal limits are not yet available. The objective of the present study was to monitor the occurrence of T-2 toxin in cereals and cereal-based foods marketed in an area of western Romania (Timis and Arad counties), using enzyme-linked immunosorbent assay (ELISA) kits. T-2 toxin was present in all analyzed samples (maize, wheat, corn flakes, breakfast cereals, biscuits), with values ranging between 0.8 g/kg and 23.4 g/kg and median value of 4.9. This study points out also the necessity of a continuous survey of cereals and cereal-based products for T-2 toxin presence and levels, and stresses the need for establishing legislative maximum admitted levels in foods.
  • Authors:
    • Silue, D.
    • Barra, A.
    • Guei, R.
  • Source: International Journal of Agricultural Sustainability
  • Volume: 9
  • Issue: 1
  • Year: 2011
  • Summary: Food and Agriculture Organization of the United Nations (FAO) conducted two projects in Cameroon on strengthening rice, and sorghum, maize and millet seed production by smallholder seed enterprises (SSEs). Farmer groups (respectively, 25 SSEs and 114 SSEs) were formed or strengthened and trained. Sixty-six selected lead farmers were trained on the administering and managing of revolving funds. The groups were then linked to the Extension Service (for continuous technical advice), Agriculture Research for Development Institution (continuous supply of needed seed), National Seed Service (seed certification) and to financial institutions (financial support). The results obtained showed that 60 and 59.6 per cent, respectively, of the groups sustained their activities two to three years after the projects ended. Total certified rice seed produced increased to 800 tonnes (t) against 267t at the beginning. For the other cereal project, the total certified seed produced was 719.2t against 497t at its beginning. The use of quality seed rice together with good agronomic practices increased yields (up to 8.0t/ha against a scant 2t/ha before). All interviewed farmers stressed that the seed business was profitable and helped achieve higher living standards and diversify their activities. Seasonal incomes were more than US$1,783.31. Finally, both FAO projects helped generate farmers' income to about US$2,114.871, produced 447,954t of cereal grain and thus improved food security and alleviated poverty. The Cameroonian success could be repeated elsewhere.
  • Authors:
    • Ewusi-Mensah, N.
    • Logah, V.
    • Tetteh, F.
  • Source: Journal of Plant Sciences
  • Volume: 6
  • Issue: 4
  • Year: 2011
  • Summary: A field experiment to evaluate Soil Organic Carbon (SOC) and maize grain yield under different soil amendments and cropping systems was conducted in 2006 and 2007 at the Soil Research Institute, Kwadaso, Kumasi. The experiment was a split plot with three replications. The main plot factor (cropping systems) consisted of continuous maize, maize/soybean intercropping and maize cowpea rotation systems, the sub-plot (amendments) comprised of Poultry Manure (PM) at 4 t ha -1, poultry manure+chemical fertilizer (PM+CF) at 2 t ha -1 (PM)+45-30-30 kg ha -1 (NPK 15-15-15), Chemical Fertilizer (CF) at 90-60-60 kg ha -1 NPK 15-15-15 and a control (no amendment). Soil samples were taken at 21 and 84 days after amendment (DAA). Generally, PM+CF produced the highest range of SOC (1.14-1.37%). The least (0.98-1.28%) was recorded on the control plots. Plots amended with chemical fertilizer alone or in combination with poultry manure out-yielded the control in maize grain yield. Positive correlations between SOC at 84 DAA and maize grain yield were recorded in the major (r=0.70*) and minor (r=0.89**) rainy seasons of 2006 which established crop yield a function of SOC at harvest. Land equivalent ratios of sole maize (maize grown under continuous maize system) and maize intercropped with soybean were