• Authors:
    • Lamers, J.
    • Djanibekov, N.
    • Khamzina, A.
    • Djanibekov, U.
  • Source: Forest Policy and Economics
  • Volume: 21
  • Year: 2012
  • Summary: This study analyzed the financial attractiveness of Clean Development Mechanism Afforestation and Reforestation (CDM A/R) in irrigated agricultural settings. The Net Present Value (NPV) and Internal Rate of Return (IRR) of CDM A/R were estimated by analyzing the case of Khorezm region in Uzbekistan, where a mixed-species tree plantation was established on marginal cropland. The dual purposes of carbon sequestration and production of fruits, leaves as fodder, and fuelwood were studied over a seven-year rotation period. We compared the opportunity costs of land in marginal agricultural areas between this short-rotation plantation forestry and the annual cultivation of the major crops in the region, i.e., cotton, winter wheat, rice, and maize. The analyses were performed considering different levels of irrigation water availability, from 0 to 30,000 m(3)/ha, to reflect the reality of a high variability of water supply in the region. The NPV of CDM A/R ranged between 724 and 5794 USD/ha over seven years, depending on the tree species. Among the latter, Elaeagnus angustifolia L had the highest profits due to the annually recurring cash flows generated from fruit production. Temporary Certified Emission Reductions (tCER) ranged within 399-702 USD/ha after the assumed 7-year crediting period and would not suffice to cover initial investments and management costs of tree plantations. IRR peaked at 65% with E. angustifolia under the conventional afforestation and measured - 10% and 61% when considering only the tCER and the CDM A/R, respectively. In contrast, other species had higher IRRs in case of the CDM A/R. The total profits from tree plantations exceeded those of both cotton and winter wheat, even with the assumption that there was an optimal irrigation supply for these crops. Rice production was overall the most profitable land use option but required water input of 26,500 m(3)/ha/year, which is not consistently available for marginal croplands. We argue that the current global average price of 4.76 USD/tCER is insufficient to initiate forestry-based CDM projects but, in the absence of other incentives, can still motivate forestation of degraded croplands for land rehabilitation and the provisioning of non-timber products. Given the low irrigation needs of trees, 3-30% of the crop water demand, a conversion of degraded cropland to forested areas could save up to 15,300 m3/ha/year at the current tCER price. Combining the monetary value of water and carbon would enlarge the scope for CDM A/R in irrigated drylands, thus enhancing the investments in marginal land rehabilitation and strengthening the resilience of rural populations to the repercussions of climate change. (C) 2012 Elsevier B.V. All rights reserved.
  • Authors:
    • Dong, H.
    • Dong, H.
  • Source: Australian Journal of Crop Science
  • Volume: 6
  • Issue: 2
  • Year: 2012
  • Summary: Soil salinity is a major threat to cotton production worldwide. Excessive salt in the soil leads to a series of physiological and biochemical metabolic disorders in cotton plants mainly as a result of osmotic effects (dehydration), nutritional imbalance and toxicity of salt ions (Na + and Cl -). The metabolic disorders may finally reduce plant growth and lint yield and quality, particularly in conditions of high salinity. Basically, combating the effects of salinity stress on cotton plants involves two main strategies: one is to improve salt tolerance through genetic breeding and chemical or biological treatment, the other is to avoid or alleviate salinity stress by improving at least part of the root-zone environment. This review highlights the technologies for combating salinity stress on cotton, with a focus on recent advances in agronomic techniques for managing salinity in the root zone. We recommend a comprehensive use of agronomic practices such as suitable cultivars, proper irrigation and fertilization, seed pretreatment, furrow seeding, plastic mulching and induction of unequal salt distribution in the root-zone to combat salinity stress. Further research should focus on exploration and understanding of the uptake and efficient use of water and nutrients in saline soils. Research should also focus on the development of new products for cotton growing in saline soils like new foliar and specific slow-release fertilizers and commercial plant growth regulators to improve salt tolerance.
  • Authors:
    • Li, D.
    • Zhang, T.
    • Li, X.
    • Zhang, Z.
    • Chen, J.
    • Wang, H. J.
    • Hou, Z. A.
    • Lv, X.
    • Dong, N.
    • Li, D.
    • Zhang, T.
    • Li, X.
    • Zhang, Z.
    • Chen, J.
    • Wang, H.
    • Hou, Z.
    • Lv, X.
    • Dong, N.
  • Source: Xinjiang Agricultural Sciences
  • Volume: 49
  • Issue: 4
  • Year: 2012
  • Summary: Objective: The purpose of this project was to explore the influence of different irrigation water amounts on cotton growth and yield under film mulch drip irrigation basing on Penman-Monteith formula. Method: Basing on Penman-Monteith formula, a plot experiment was carried out according to a certain gradient of the irrigation amount combining with meteorological data and soil moisture to analyze the changing regularity of dry matter accumulation, water consumption, and discuss the relationship among dry matter accumulation, yield and water consumption. Result: Dry matter accumulation of cotton in different growth stages complies with the "S" type changing regularity. The soil moisture content is basically at the suitable condition of water requirement in each cotton growth stage according to the recommend irrigation water amount basing on Penman-Monteith formula, and soil moisture was fully made use of and the goal of water-saving without influencing cotton growth was achieved. The daily average transpiration of cotton presented "low-high-low" tendency in the whole growth stage. The fitting result of dry matter accumulation and water consumption ( R=0.857 8) showed that there was a significant correlation between them. The regression model was established with seed cotton yield ( Y) and irrigation amount ( X): Y=-0.010 8 X2+7.906 9 X-1 029.9 ( R2=0.926 2). Conclusion: The irrigation amount based on the theory of Penman formula basically met the cotton water requirement of each growth stage.
  • Authors:
    • Özbek, N.
    • Göre, M. E.
    • Erdoğan, O.
  • Source: Bitki Koruma Bülteni
  • Volume: 52
  • Issue: 1
  • Year: 2012
  • Summary: The effects of barley and common vetch on Verticillium wilt intensity were examined at Nazilli Cotton Reserach experiment fields during 2006-2007. Applications used in experiment were planted as barley, barley+common vetch, common vetch (traditional production), common vetch (growing at last irrigation) and control (conventional cotton production). After a four weeks residue decomposition period, seeds of Nazilli 84-S cotton variety were planted in a randomized complete block design with four replications. The data for disease intensity were determined during the stage of 5-10%, 50-60% cotton boll opening and after harvest. Seed cotton yield and fiber quality properties were also determined. Disease intensity identified according to symptoms on leaf and cross section of stems was determined lower level in organic growing plots and it was followed by control growing plot. During experiments, green manure applications of barley and barley+common vetch provided with a larger decrease on disease intensity than control growing plot. This also shows that cotton growing increase disease intensity every year. In common vetch and control plots, average yield values were determined higher according to barley+common vetch and barley growing plots. Cotton fiber properties have not been affected by these treatments.
  • Authors:
    • Liu, Z.
    • Li, K.
    • Cao, C.
    • Zheng, C.
    • Sun, J.
    • Zhang, J.
    • Feng, D.
  • Source: Transactions of the Chinese Society of Agricultural Engineering
  • Volume: 28
  • Issue: 8
  • Year: 2012
  • Summary: In order to use the mineralized shallow groundwater to relieve the crisis of freshwater resources shortage, the 5 years field experiment under border irrigation with mineralized water before sowing was conducted. The response relations among different salt stress levels and cotton growth index and seed cotton yield were analyzed in this study, and the cotton salt tolerance appraisal indices and eigenvalue under border irrigation with different saline water before sowing were put forward. The results showed that the relative emergency rate, relative plant height, relative leaf area, relative above-ground dry matter mass, relative fruit branch number, relative boll number and relative maximum of buds, flowers and bolls all could be used as salt tolerance appraisal indices of cotton. The relative height was recommended as the most practical salt tolerance appraisal index among them because it was easy to observation and sensitive to salt stress. The salinity of irrigation water should be below 5.48 g/L when the yield of seed cotton in saline water treatment was consistent with the fresh water irrigation treatment after a 5-year continuous irrigation.
  • Authors:
    • Frisvold, G. B.
    • Konyar, K.
  • Source: Water Resources Research
  • Volume: 48
  • Issue: 5
  • Year: 2012
  • Summary: This study examined how agriculture in six southwestern states might adapt to large reductions in water supplies, using the U.S. Agricultural Resource Model (USARM), a multiregion, multicommodity agricultural sector model. In the simulation, irrigation water supplies were reduced 25% in five Southern Mountain (SM) states and by 5% in California. USARM results were compared to those from a "rationing" model, which assumes no input substitution or changes in water use intensity, relying on land fallowing as the only means of adapting to water scarcity. The rationing model also ignores changes in output prices. Results quantify the importance of economic adjustment mechanisms and changes in output prices. Under the rationing model, SM irrigators lose $65 in net income. Compared to this price exogenous, "land-fallowing only" response, allowing irrigators to change cropping patterns, practice deficit irrigation, and adjust use of other inputs reduced irrigator costs of water shortages to $22 million. Allowing irrigators to pass on price increases to purchasers reduced income losses further, to $15 million. Higher crop prices from reduced production imposed direct losses of $130 million on first purchasers of crops, which include livestock and dairy producers, and cotton gins. SM agriculture, as a whole, was resilient to the water supply shock, with production of high value specialty crops along the Lower Colorado River little affected. Particular crops were vulnerable however. Cotton production and net returns fell substantially, while reductions in water devoted to alfalfa accounted for 57% of regional water reduction.
  • Authors:
    • Blanco-Lopez, M. A.
    • Perez-Rodriguez, M.
    • Garcia-Cabello, S.
    • Lopez-Escudero, F. J.
  • Source: European Journal of Plant Pathology
  • Volume: 133
  • Issue: 4
  • Year: 2012
  • Summary: Verticillium dahliae Kleb. causes Verticillium wilts in many herbaceous and woody species. Many hosts of the pathogen are commonly cultivated in Andalucia (southern Spain), particularly major crops such as cotton, vegetables, almond, peach and, particularly, olive, in which the fungus causes Verticillium wilt of olive. Infective structures of the pathogen (microsclerotia), produced in the late phases of the infection cycle in senescent tissues of the infected plants, can be spread over short or long distances by a number of dispersal methods. Irrigation water is one of the factors implicated in this spread of V. dahliae. Indeed, increasing irrigation dosages in crops or an inadequate irrigation schedule have been identified as cultural practices favouring Verticillium wilt onset and severity in olive and other hosts. Most of the cultivated areas in the Guadalquivir Valley of Andalucia are irrigated by pumping stations using modern infrastructures that supply water to thousands of hectares of farm land, which are usually associated with irrigation communities. This study demonstrates that the pathogen survives in the sediment and particles suspended in water used for irrigation in different facilities of an irrigation community, that were involved in distributing water (main canal and reception tank of a investigated pumping station, irrigation pools and sand from filters). Thus microsclerotia moves from the pumping station to individual plots (olive and cotton cultivated farm) as viable microsclerotia, free or embedded in soil particles and plant debris, suspended in the irrigation water, or deposited in the sludge in piping systems or water storage ponds. We have detected amounts of inoculum in the solid pellet samples in these facilities that ranged from 2.7 to 6.7 microsclerotia per gram. Besides this, water from drippers in cultivated plots released into the soil a variable amount of infective propagules of the pathogen over time that accounted for 3.75 microsclerotia/m 3 in some of the recording times. Therefore, irrigation water becomes an important source of inoculum that is very effectively involved in medium and long-distance spread of the pathogen.
  • Authors:
    • García-Vila, M.
    • Fereresa, E.
  • Source: European Journal of Agronomy
  • Volume: 36
  • Issue: 1
  • Year: 2012
  • Summary: Water resources used in irrigated agriculture are increasingly scarce, particularly in many countries where irrigation has undergone recent expansion. To optimize the limited resources available, optimization models provide useful tools for technical and economic analyses. One of the key inputs of these models is the yield response to water which is often simulated with empirical water production functions. At present, dynamic crop simulation models, such as AquaCrop (Steduto et al., 2009) offer alternative predictions of crop responses to different irrigation strategies as inputs to economic optimization. A model at farm scale was developed and applied to an area in South-western Spain to assist farmers in pre-season decision making on cropping patterns and on irrigation strategies. Yield predictions were obtained from the AquaCrop model which was validated for four different crops. The model simulated the impact on farm income of: (a) irrigation water constraints; (b) variations in agricultural policies; (c) changes in product and water prices; and, (d) variations in the communication to farmers of the specific level of irrigation water allocation. The applications of the models to the study area showed that currently, the changes in cropping patterns induced by the agricultural policy will encourage water savings more than an increase in water prices. Under water restrictions, the best strategy combines planting of low water use crops in part of the area to release water to grow more profitable crops with greater water needs. The model predicted a strong negative impact on farm income of delaying a decision on the level of seasonal water allocation by the water authority, reaching up to 300 ha(-1) in the case of the study area. (C) 2011 Elsevier B.V. All rights reserved.
  • Authors:
    • Khavari, F.
    • Ghaderi-Far, F.
    • Sohrabi, B.
  • Source: International Journal of Plant Production
  • Volume: 6
  • Issue: 1
  • Year: 2012
  • Summary: Restricted water resources are a limiting factor for irrigation applications throughout the world. The effects of irrigation regimes (amount) on cotton lint yield are known, but there is little information on the effect of irrigation regimes on seed quality of cotton. In this study, the effects of deficit irrigation after the onset of flowering on lint yield and seed quality of cotton (Gossypium hirsutum L.) with a drip irrigation system were evaluated during 2006 and 2007 in the northern Iran. After the onset of flowering, four irrigation regimes (0, 40, 70 and 100% of Class A pan evaporation (%PE)) were applied when the cumulative evaporation amount from class A pan reached approximately 40-50 mm. Lint yield showed a quadratic response to %PE and maximum lint yields were achieved with 82 and 91% PE irrigation regimes in 2006 and 2007, respectively and seed quality (based on standard germination and seed vigor tests) increased with a decrease in deficit irrigation. Thus when the amount of applied water was reduced by 30 (70% PE) and 60% (40% PE), decrease in lint yield was about 4 and 14%, respectively. The results of this study showed that irrigation treatments of 40-70% PE would be optimum for lint yield and seed quality production under drip irrigation.
  • Authors:
    • Hague, S.
    • Hequet, E.
    • Smith, W.
    • Ng, E. H.
    • Gregory, K.
  • Source: Crop Science
  • Volume: 52
  • Issue: 3
  • Year: 2012
  • Summary: The U.S. cotton (Gossypium spp.) industry has shifted focus in recent years to an export market, necessitating further development of upland cotton (G. hirsutum L.) cultivars with superior fiber properties to maintain competitiveness. This study was conducted to compare both fiber and yarn performance of upland cotton genotypes with similar average fiber length but enhanced fiber bundle strength (Str) with two high quality commercial controls, 'FM 832LL' and 'DP 491'. The high Str strains and commercial upland controls were grown in Weslaco, TX, during the summers of 2009 and 2010 with standard agronomic practices for south Texas, including furrow irrigation. Plots were spindle-machine harvested, seedcotton ginned on a research gin without a lint cleaner, and lint and yarn tested at the Fiber and Biopolymer Research Institute (FBRI) in Lubbock, TX. Lint and yarn data collected included high volume instrument (HVI) and advanced fiber information system (AFIS) derived data and ring spun yarn data (mini-spinning protocol). Years were different for almost every fiber and yarn property except Str, immature fiber content (IFC), yarn tenacity (Ten), work required for yarn breakage (Work to Break) and the number of thin places per kilometer that are at least 50% smaller in diameter than adjacent portions of yarn (Thin). All of the high Str strains had higher Ten in 2009 than the controls and 9 of the 11 had higher Ten in 2010. The high Str genotypes resulted in more even yarns (as determined with the Uster Tester 3 [Uster Technologies]).