• Authors:
    • Evans, N.
    • Agbola, F.
  • Source: Agricultural Systems
  • Volume: 107
  • Year: 2012
  • Summary: Although water markets have been in operation for nearly 30 years, previous empirical studies have ignored farmer's land use response to water trading in the Murray-Darling Basin (MDB), Australia. A Nerlovian partial adjustment model of rice and cotton acreage response in the MDB were specified and estimated using data for the period 1965-2008. The results indicate that acreage response for rice and cotton with respect to the price of water are inelastic in both the short- and long-run. The findings of this study bring into question the effectiveness of water trading scheme as the primary means of ensuring the efficient use of water and highlight the need for other complementary measures in the MDB. The results of this study highlight the complex interdependencies of many factors that influence farmer's land use decisions and draw an important conclusion that although water trading has increased the efficient use of irrigated water, its impact on farmers' land use decisions has been too small to stimulate any significant reduction in irrigated water usage in the MDB. (C) 2011 Elsevier Ltd. All rights reserved.
  • Authors:
    • Shivakoti, G.
    • Nawaz, R.
    • Perret, S.
    • Ahmad, S.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 10
  • Issue: 2
  • Year: 2012
  • Summary: This paper investigated the farm level diversity in operation and farm performances under two different governance situations in irrigation systems of Punjab Province of Pakistan: Farmer-Managed (FMIS) and Government-Managed Irrigation Scheme (GMIS). Questionnaire surveys and multivariate analyses were conducted. Farms typology was developed based on farm size. Results reveal a water-land-farming strategy nexus. Larger farms perform better in both schemes. Wheat cropping is a strategic choice, specialized, and exclusive, with low input, and low income. Conversely, maize and rice cropping tit well in diversification and intensification strategies, leading to higher farm income. Also poor financial basis and extension services for smaller farms do not support intensification and diversification. The paper shows that productivity of production factors, level of intensification, farm size are closely interlocked, in a general context of poor performances and institutional reforms. Groundwater access is also a key to success, since canal irrigation only cannot sustain an intensification-diversification process. The paper concludes that transfer of canal irrigation management to farmers will not solve all issues, and yet remains probably the only long-term solution. Areas for public intervention on, inter alia, land, finance, extension, markets remain necessary in FMIS and towards smaller farms.
  • Authors:
    • Callado, S.
    • Albino, J.
  • Source: Emirates Journal of Food and Agriculture
  • Volume: 24
  • Issue: 4
  • Year: 2012
  • Summary: The article is based on an agro-ecological evaluation of seven different agricultural systems in Teresopolis, Rio de Janeiro. The studied systems are dealing with: vegetable production system, ecological husbandry, cattle production system, sylvopastoral approaches as well as citrus cropping systems. The main objective is to evaluate the environmental impact of these systems using the "Emergy Analysis" as methodology. For this purpose, input data as materials, services, natural renewable/nonrenewable sources of 42 crops were analyzed. This method is based on energy flows, transforming all inputs and outputs in a common unit. This analysis allows comparisons across agricultural systems and their environmental impacts, as well as, makes possible the identification of scenarios to achieve greater sustainability. The main conclusions of this study are: the vegetable systems have large amounts of energy invested in irrigation, fertilizers and fuels; the largest value of sustainability corresponds to the ecological systems and it has the capacity to save capital in form of biomass in the system; cattle system causes bigger environmental damage and have the smallest yield per hectare in economic and energy terms; as for the citrus systems, a low investment rate was found and the use of renewable resources from this system is comparable to the vegetable systems.
  • Authors:
    • Hussain, A.
    • Chattha, T.
    • Ahmad, Sh.
    • Tariq, N.
    • Ali, H.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 10
  • Issue: 2
  • Year: 2012
  • Summary: A field study was conducted during 2006-2007 and 2007-2008 at Central Cotton Research Institute, Multan, Pakistan, on silt loam soils to evaluate the effect of irrigation at different growth stages and phosphorus application methods on agronomic traits of wheat. The field experiments were laid out in a split plot design with three replications. The irrigation treatments, i.e. control - no irrigation (I-1), two irrigations at crown root and booting stage (I-2), three irrigations at crown root, booting and grain development (I-3), four irrigations at crown root, booting, anthesis and grain development (I-4) and live irrigations at crown root, booting, caring, anthesis and grain development (I-5) were kept in main plots. The subplots were allocated to three phosphorus application methods viz. side dressed, 3 inches aside seed (I-1), broadcasting at the time of seedbed preparation (P-2), and top dressing alter first irrigation (P-3). Data on yield components such as tiller number m(-2), spikelet number spike(-1), number of grains spike(-1) and 1000-grain weight as well as grain and total dry matter (TDM) yields were collected. Full irrigation (I-4, I-5) treatments significantly affected yield and yield components. A reduction in all studied characters of wheat crop was subjected to water stress at low or greater degree (e.g. I-1, I-2, and I-3). Phosphorus application as side dressed (P-1), 3 inches aside seed, was more beneficial for increasing yield and yield components of wheat compared to other methods of P application.
  • Authors:
    • Bani-Hani, N.
    • Osaili, T.
    • Angor, M.
    • Ajo, R.
    • Al-Rousan, W.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 10
  • Issue: 2 Part 1
  • Year: 2012
  • Summary: The effect of different irrigation levels on the Navel orange fruit quantity and quality was studied in the Jordan Valley through the 2007 and 2008 production seasons. Irrigation treatment consisted of control irrigation at 100% of crop evapotransperation and two deficit irrigation treatments. The latter irrigation treatments consisted of treatment at 75% of control irrigation, and at 50% of control irrigation. Fruits were harvested at five different periods, starting at the beginning of November in both seasons; harvesting took place at two-week intervals. The yield in both seasons of treatment at 75% of control irrigation was not affected significantly (p>0.05) compared with control. Yield of treatment at 75% of control irrigation was 36.1 t ha -1 and 26.17 t ha -1 in 2007 and 2008, respectively. As for control treatment, it was 35.17 and 28.15 t ha -1 for the same seasons. The yield of treatment at 50% of control irrigation was 29.16 t ha -1 for 2007 and 20.43 t ha -1 for 2008, indicating significant reduction (p≤0.05). Total soluble solids, titratable acidity, and their ratio increased when reducing water irrigation. At the same time, juice percent and vitamin C were not nearly significantly different. Yield increased as harvesting progressed up to the third harvesting period (beginning of December) and started to decline by mid December. Fruits harvested at different periods showed a slight increase of juice percentage. Total soluble solids, total soluble solids/titratable acidity, and pH value increased significantly. A decrease of titratable acidity and vitamin C occurred as harvesting approached the third period. The results showed identical trends in both production seasons. From these results, two main conclusions can be obtained. First, the implementation of the 75% deficit irrigation instead of full irrigation would be recommended to save water while sustaining the same quantity and quality of yield. Second, the third harvesting period (beginning of December) is the more profitable harvesting period for Navel oranges at the different irrigation levels.
  • Authors:
    • Collins, H.
    • Moore, A.
    • Alva, A.
  • Source: Journal of Crop Improvement
  • Volume: 26
  • Issue: 2
  • Year: 2012
  • Summary: Potato ( Solanum tuberosum L.) tuber yield and quality are impacted by irrigation and nitrogen (N) management. This study was conducted in the Pacific Northwest (PNW) region of United States to evaluate the effects of deficit irrigation (DI) and rates of pre-plant and in-season N applications on Ranger Russet and Umatilla Russet cultivars. In 2004, with Ranger Russet only, DI with 20% lower total irrigation for the entire growing period resulted in 28% tuber yield reduction compared to that of plants irrigated to replenishment full evapotranspiration (ET), i.e., full irrigation (FI). A subsequent study in 2006 and 2007 with DI (14% to 17% deficit) resulted in tuber yield reduction of 7% to 10% in both cultivars compared to full ET irrigation. Yield reduction in DI was generally attributed to reduction in large weight tubers, >0.227 kg/tuber, in both cultivars across three years. Petiole NO 3-N concentrations were greater in plants grown under DI as compared to those of plants in full ET irrigation across all years and cultivars, particularly during tuber maturation stage. This is an important consideration as increased N availability during the late growing season adversely affects tuber quality. Petiole NO 3-N concentrations increased with increased in-season N rates. In 2007, 112 kg.ha -1 in-season N resulted in petiole NO 3-N concentrations below desirable concentrations across most of the growing season in both cultivars. This, in turn, contributed to a significant reduction in tuber yield as compared to the 224 kg.ha -1 in-season N rate. Continuous DI with 14% to 20% reduction in water as compared to irrigation to replenish full ET, begun three to four weeks after seedling emergence, had significant negative effects on tuber yields of both cultivars in high-production irrigated growing conditions. Application of N up to 112 kg ha -1 as pre-plant soil applied plus 224 kg ha -1 of in-season fertigation in five applications at two-week intervals beginning four weeks after seedling emergence appears to be adequate to support high yields of high-quality tubers.
  • Authors:
    • Moore, A.
    • Ren, H.
    • Alva, A.
  • Source: American Journal of Plant Sciences
  • Volume: 3
  • Issue: 1
  • Year: 2012
  • Summary: Biomass accumulation and partitioning into different plant parts is a dynamic process during the plant growing period, which is influenced by crop management and climate factors. Adequate knowledge of biomass partitioning is important to manage the crops to gain maximum partitioning of assimilates into plant parts of economic significance, i.e. tubers in potato. This study was conducted using two potato cultivars grown in a sandy soil with center pivot irrigation under full irrigation (FI; irrigation to replenish 100% of water loss by evapotranspiration [ET]) and deficit irrigation (DI; replenish only 80% ET) and two nitrogen(N) rates (pre-plant + in-seasonN rates of 56+112 or 168+336 kg/ha). Plant samples were taken on 22, 44, 66, and 98 days after seedling emergence (DAE). With high N rate, tuber biomass of 'Umatilla Russet' cultivar in relation to total plant biomass varied from 23%-88% and 25%-86% over 22 to 98 DAE for the FIand DI treatments, respectively. The corresponding partitioning ranges were 30%-93% and 38%-93% at the low N rate. With respect to the'Ranger Russet' cultivar, biomass partitioning to tubers ranged from 36%-82% and 23%-84% for the FIand DI, respectively, at the high N rate, and 29%-87% and 39%-95% at the low N rate. Overall, this study demonstrated that within the range of N rate and irrigation treatments the biomass portioning into tubers was largely similar in both cultivars.
  • Authors:
    • Berger, P.
    • Santos, D.
    • Silva, T.
    • Aquino, R.
    • Aquino, L.
  • Source: REVISTA BRASILEIRA DE ENGENHARIA AGRICOLA E AMBIENTAL
  • Volume: 16
  • Issue: 4
  • Year: 2012
  • Summary: This work aimed to evaluate the effect of phosphorus application in rainfed and irrigated crop on shoot dry matter, the absorption and nutrient exportation, and yield of cotton crop. The experiment was carried out in a Psament in the northeren part of Minas Gerais State, Brazil. The experimental design was in randomized blocks with four replications in a factorial arrangement of two doses of P 2O 5 * two cropping systems. Two additional treatments in each system without phosphorus application completed six studied treatments. Accumulation of dry biomass, absorption and exportation of nutrients, and yield of seed cotton were evaluated. Phosphorus levels did not influence the accumulation of shoot dry biomass. P supply increased the exportation of P, Ca, Mg, S, and Mn under irrigated and of N, K, and Fe regardless of the cropping system. Irrigation increased the dry biomass of leaves, stems, and shoots at 80 days after emergency, and the absorption of N, P, K, Ca, Mg, S, Cu, Fe, Mn, Zn, and B, as well as their exportation by the crop. There was an increase in the number of bolls per plant, fiber yield and productivity through the irrigation use. Increasing productivity with P application was conditioned to irrigation.
  • Authors:
    • Ribeiro Junior, P.
    • Teixeira, M.
    • Coelho, R.
    • Armindo, R.
  • Source: ENGENHARIA AGRICOLA
  • Volume: 32
  • Issue: 3
  • Year: 2012
  • Summary: This study aimed to evaluate the spatial variability of leaf content of macro and micronutrients. The citrus plants orchard with 5 years of age, planted at regular intervals of 8*7 m, was managed under drip irrigation. Leaf samples were collected from each plant to be analyzed in the laboratory. Data were analyzed using the software R, version 2.5.1 Copyright (C) 2007, along with geostatistics package GeoR. All contents of macro and micronutrients studied were adjusted to normal distribution and showed spatial dependence. The best-fit models, based on the likelihood, for the macro and micronutrients were the spherical and matern. It is suggest for the macronutrients nitrogen, phosphorus, potassium, calcium, magnesium and sulfur the minimum distances between samples of 37; 58; 29; 63; 46 and 15 m respectively, while for the micronutrients boron, copper, iron, manganese and zinc, the distances suggests are 29; 9; 113; 35 and 14 m, respectively.
  • Authors:
    • Yazdanpanah, N.
    • Kouhi, N.
    • Asadi, R.
  • Source: Journal of Food Agriculture & Environment
  • Volume: 10
  • Issue: 1
  • Year: 2012
  • Summary: With population growing throughout the world, it is necessary to optimize water use especially in agriculture land. In order to determine water use efficiency (WUE) of cotton using micro irrigation system, a field experiment was conducted in the Agricultural and Natural Resource Research Institute of Orzoueyeh, Kerman province. The experiment was carried out in split plot design based on Randomized Complete Block Design (RCBD) with three replications. The treatments were comprised of three levels of crop water requirements (i.e. I-1 I-2 and I-3, that are irrigation based on 125, 100 and 75% water requirement, respectively) in main plot and two tape position as sub plot including conventional (r(1)) and alternative (r(2)) patterns. All treatments were assessed for productivity, water use and its efficiency, and economic issues, as well. The results showed that the yield obtained from I-1 was 379 and 1204 kg ha(-1) higher than that of I-2 and I-3, respectively. In addition, the obtained yield due to r(1) system was 377 kg ha(-1) more than in the r(2) pattern. However, interaction between treatments on crop yield indicated that the I(1)r(1) treatment resulted in the maximum yield. Despite of use water equality in sub plots, WUE in r(1) was 16% higher than in r(2). However, economic assessment exhibited that system cost in the r(2) in comparison with the r(1) was 11% lower.