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Sample records for irrigated rice grown

  1. Assessment of arsenic in Australian grown and imported rice varieties on sale in Australia and potential links with irrigation practises and soil geochemistry.

    Science.gov (United States)

    Fransisca, Yunnita; Small, Darryl M; Morrison, Paul D; Spencer, Michelle J S; Ball, Andrew S; Jones, Oliver A H

    2015-11-01

    Chronic dietary exposure to arsenic, particularly the inorganic forms (defined as elemental arsenic, predominantly As(3+) and As(5+), and all its inorganic compounds except arsine), is a matter of concern for human health. Ingestion of arsenic usually occurs via contaminated water but recent studies show there is also a risk of exposure from food, particularly Asian rice (Oryza sativa). Australia is a rice growing country, contributing around 2% of the world rice trade, and a large proportion of the population consumes rice regularly. In the present study we investigated concentrations of arsenic in both Australian grown and imported rice on sale in Australia and examined the potential links with irrigation practises and soil geochemistry. The results indicated a wide spread of arsenic levels of 0.09-0.33 mg kg(-1), with Australian grown Arborio and sushi varieties of O. sativa containing the highest mean value of ∼0.22 mg kg(-1). Arsenic levels in all samples were below the 1 mg kg(-1) limit set by Food Standards Australia New Zealand. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Rice Photosynthetic Productivity and PSII Photochemistry under Nonflooded Irrigation

    Directory of Open Access Journals (Sweden)

    Haibing He

    2014-01-01

    Full Text Available Nonflooded irrigation is an important water-saving rice cultivation technology, but little is known on its photosynthetic mechanism. The aims of this work were to investigate photosynthetic characteristics of rice during grain filling stage under three nonflooded irrigation treatments: furrow irrigation with plastic mulching (FIM, furrow irrigation with nonmulching (FIN, and drip irrigation with plastic mulching (DI. Compared with the conventional flooding (CF treatment, those grown in the nonflooded irrigation treatments showed lower net photosynthetic rate (PN, lower maximum quantum yield (Fv/Fm, and lower effective quantum yield of PSII photochemistry (ΦPSII. And the poor photosynthetic characteristics in the nonflooded irrigation treatments were mainly attributed to the low total nitrogen content (TNC. Under non-flooded irrigation, the PN, Fv/Fm, and ΦPSII significantly decreased with a reduction in the soil water potential, but these parameters were rapidly recovered in the DI and FIM treatments when supplementary irrigation was applied. Moreover, The DI treatment always had higher photosynthetic productivity than the FIM and FIN treatments. Grain yield, matter translocation, and dry matter post-anthesis (DMPA were the highest in the CF treatment, followed by the DI, FIM, and FIN treatments in turn. In conclusion, increasing nitrogen content in leaf of rice plants could be a key factor to improve photosynthetic capacity in nonflooded irrigation.

  3. Effects of irrigation strategies and soils on field grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Andersen, Mathias Neumann; Plauborg, Finn

    2010-01-01

    Yield and water productivity of potatoes grown in 4.32 m2 lysimeters were measured in coarse sand, loamy sand, and sandy loam and imposed to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. PRD and DI as water-saving irrigation treatments received 65% of FI after...

  4. Effects of irrigation strategies and soils on field grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Plauborg, Finn; Andersen, Mathias Neumann

    2011-01-01

    Root distribution of field grown potatoes (cv. Folva) was studied in 4.32m2 lysimeters and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. Drip irrigation was applied for all irrigations. Irrigations were run in three different soils: coarse sand......, loamy sand, and sandy loam. Irrigation treatments started after tuber bulking and lasted until final harvest with PRD and DI receiving 65% of FI. Potatoes irrigated with water-saving irrigation techniques (PRD and DI) did not show statistically different dry root mass and root length density (RLD, cm...... density in the furrow. Most roots accumulated in the surface layers of coarse sand as compared to the other soil types. In the deep soil profile (30–70 cm) a higher root density was found in loamy sand compared with the sandy loam and coarse sand. Approximately twice the amounts of roots were found below...

  5. land evaluation for improved rice production in watari irrigation

    African Journals Online (AJOL)

    DR. AMINU

    This study aimed at raising irrigated rice production in Watari Irrigation scheme, in Kano state, as to bridge the gap ... land including details about maintenance and ... Area of Kano state and cover a total of 4,574 .... which requires a depth of more than 50cm for efficient .... raise the productivity of the soils to optimum for.

  6. Towards a smart automated surface irrigation management in rice-growing areas in Italy

    Directory of Open Access Journals (Sweden)

    Daniele Masseroni

    2017-02-01

    Full Text Available Italy is the leading rice producer in Europe, accounting for more than half of the total high-quality production of this crop. Rice is traditionally grown in fields that remain flooded starting with crop establishment until close to harvest, and this traditional irrigation technique (i.e., continuous submergence is recognised as an important water resource sink (almost 40% of the irrigation water available worldwide is used for paddy areas. Meanwhile, the water management in rice areas requires a high level of labour because it is based on maintaining a predetermined water height in paddy fields and because the regulation of input and output flow is typically operated manually by the farmer. This study reveals the hardware and software characteristics of an automated and remote controlled technology tested for the first time in a rice farm near Pavia (Italy, during the 2016 growing season, aiming at a more efficient and less burdensome irrigation management system for rice fields. A water level sensor in the field provides the data required to govern the inflow regulation gate in real-time, according to the precise time to cut off the flow rate. Using a dedicated web page, the farmer can control flows, volumes and water levels in the fields by operating directly on the gate if necessary or setting the irrigation program according to his agronomic practices.

  7. The rice agroecosystem of the MUDA irrigation scheme: an overview

    International Nuclear Information System (INIS)

    Ho Nai Kin

    2002-01-01

    The Green Revolution technologies were introduced to the Muda area of Malaysia in the late 1960s. These technological innovations have resulted in rapid modification of the crop habitat and triggered a chain reaction in the rice agroecosystem. The impact of these technologies on the pest flora and fauna are significant. Indiscriminate use of pesticides causes disruption of natural enemy equilibrium and other undesirable effects to the farmers and the rice environment. The main emphasis of this paper is focused on the interactions between the various biological factors such as pathogenic microorganisms, arthropods, gastropods, fishes, birds, rodents, weeds, and the physical factors in the rice agroecosystem. The impact of double cropping of rice, the provision of irrigation facilities, the changes of crop establishment methods, and the adoption of pesticides on the rice agroecosystem are found to have far reaching effects on the sustainability of rice production in the Muda area. (Author)

  8. INVENTORY OF IRRIGATED RICE ECOSYSTEM USING POLARIMETRIC SAR DATA

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    P. Srikanth

    2012-08-01

    Full Text Available An attempt has been made in the current study to assess the potential of polarimetric SAR data for inventory of kharif rice and the major competing crop like cotton. In the process, physical process of the scattering mechanisms occurring in rice and cotton crops at different phonological stages was studied through the use of temporal Radarsat 2 Fine quadpol SAR data. The temporal dynamics of the volume, double and odd bounce, entropy, anisotropy, alpha parameters and polarimertic signatures, classification through isodata clustering and Wishart techniques were assessed. The Wishart (H-a classification showed higher overall as well as rice and cotton crop accuracies compared to the isodata clustering from Freeman 3-component decomposition. The classification of temporal SAR data sets independently showed that the rice crop forecasting can be advanced with the use of appropriate single date polarimetric SAR data rather than using temporal SAR amplitude data sets with the single polarization in irrigated rice ecosystems

  9. Scaling up Intermittent Rice Irrigation for Malaria Control on the ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The water used for rice farming is a breeding ground for malarial mosquitoes that ... climate variability and change are threatening the sources of irrigation water and ... skills (farmer-to-farmer agricultural extension); - assess and document social, ... Adaptation strategies for two Colombian cities were discussed at ADAPTO's ...

  10. Influence of pH of acid irrigation water on the transfer of elements into rice plant from soils

    International Nuclear Information System (INIS)

    Maeno, Tomokazu; Tanizaki, Yoshiyuki

    1996-01-01

    Rice plant samples were grown in 14 cultivative pots under six different pH conditions of acid irrigation water (pH: 6.5, 6.0, 4.5, 3.5, 3.0. 2.5) and ion exchange water (pH: 7.5), in order to study an influence of pH of irrigation water on the transfer of elements into rice plant from soils. The acid irrigation water was prepared by adding mixed solution of 1N H 2 SO 4 and 1N HNO 3 (1:1) to ion exchange water. The rice grain yielded was separated into three parts, i.e., polished rice, bran and chaff and they were powdered one by one. The contents of twenty five elements in the three parts of grain (14 samples each) were determined by a neutron activation analysis. It was clarified that the contents of Cu, Zn, Fe, Cr, Mg, Rb, Mo, Ni, and Cs in the polished rice increased with decreasing pH of the acid irrigation water. The contents of Se and Br, on the contrary, decreased. Significant changes of the contents were not observed for Na, Al, Sc, Mn, Cl, Ca, V and Co. The relationships between the contents of elements in the bran or chaff and pH of the acid irrigation water were not so clear as the case of polished rice. The enrichment factor of trace elements from soils was calculated for the polished rice, bran and chaff The high enrichment of Cl, Mo, Zn, Se and Cu was observed in the polished rice. Manganese and Cr were concentrated more in the bran than in the polished rice. (author)

  11. Transfer of radioactive and chemical pollutants into irrigated rice fields

    International Nuclear Information System (INIS)

    Myttenaere, C.; Mousny, J.-M.; Dabin, P.; Bittel, R.

    1975-01-01

    In a general study on the consequences of radioactive and chemical releases in continental waters, flooded rice fields must be considered as a very important ecosystem due to the very large quantities of water used. In order to approach as much as possible to the natural conditions (irrigated rice fields of Northern Italy) ''mini-rice fields'' were built and local practices were respected. The behavior of activation and fission products ( 137 Cs, 60 Co, 65 Zn, 51 Cr...) and heavy metals pollutants (Cd, Cr, Sn) was studied and the transfer from water to soil and plant was followed. Concentration factors were calculated for the different organs of the plant and the impact of rice ingested to the dose delivered to man was evaluated [fr

  12. EFFECT OF NITROGEN-FIXING BACTERIA ON GRAIN YIELD AND DEVELOPMENT OF FLOODED IRRIGATED RICE

    Directory of Open Access Journals (Sweden)

    AMAURI NELSON BEUTLER

    2016-01-01

    Full Text Available This study aimed at evaluating the effect of Azospirillum brasilense , a nitrogen - fixing bacterium, on flooded irrigated rice yield. Evaluations were carried out in a shaded nursery, with seedlings grown on an Alfisol. Were performed two sets of experiments. In the first, were carried out four experiments using the flooded rice cultivars INIA Olimar, Puitá Inta - CL, Br Irga 409 and Irga 424; these trials were set up as completely randomized design in a 5x4 factorial scheme, with four replications. Treatments consisted of five nitrogen rates (0, 40, 80, 120 and 160 kg ha - 1 and four levels of liquid inoculant Ab - V5 and Ab - V6 - A. brasilense (0, 1, 2 and 4 times the manufacturer's recommendation without seed treatment. In second set, were performed two experiments using the cultivars Puitá Inta - CL and Br Irga 409, arranged in the same design, but using a 4x2 factorial. In this set, treatments were composed of four levels of Ab - V5 and Ab - V6 - A. brasilense liquid inoculant (0, 1, 2 and 4 times the recommendation of 100 mL ha - 1 , using rice seeds with and without insecticide and fungicide treatment. Shoot dry matter, number of panicles, and rice grain yield per pot were the assessed variables. The results showed that rice seed inoculation with A. brasilense had no effects on rice grain yield of the cultivars INIA Olimar, Puitá Inta - CL, Br Irga 409 and Irga 424.

  13. Soil quality and rice productivity problems in Sahelian irrigation schemes

    NARCIS (Netherlands)

    Asten, van P.J.A.

    2003-01-01

    In irrigation schemes in theSahel, rice yields and cropping

  14. The effect of irrigated rice cropping on the alkalinity of two alkaline rice soils in the Sahel

    NARCIS (Netherlands)

    Asten, van P.J.A.; Zelfde, van 't J.A.; Zee, van der S.E.A.T.M.; Hammecker, C.

    2004-01-01

    Irrigated rice cropping is practiced to reclaim alkaline-sodic soils in many parts of the world. This practice is in apparent contrast with earlier studies in the Sahel, which suggests that irrigated rice cropping may lead to the formation of alkaline-sodic soils. Soil column experiments were done

  15. Soil to rice transfer factors for 210Pb: a study on rice grown in India

    International Nuclear Information System (INIS)

    Karunakara, N.; Rao, Chetan; Ujwal, P.; Yashodhara, I.; Sudeep Kumara; Somashekarappa, H.M.; Bhaskara Shenoy, K.; Ravi, P.M.

    2013-01-01

    India is the second largest producer of rice (Oryza sativa L.) in the world and rice is the essential component of the diet for the majority of the population of India. However, detailed studies aimed at evaluation of radionuclide transfer factors (F v ) for rice grown in India are almost non-existent. This paper presents soil to rice transfer factors for 210 Pb for rice grown in natural field conditions on the West Coast of India. A rice field was developed very close to the Kaiga nuclear power plant for the field studies. For a comparative study of radionuclide transfer factors, rice samples were also collected from the rice fields of nearby villages. The soil to un-hulled rice grain 210 Pb varied in the range <1.2 x10 -2 to 8.1 x 10 -1 with a mean of 1.4 x 10 -1 . The mean values of un-hulled grain to white rice processing retention factors (F r ) was 0.03 for 210 Pb. Using the processing retention factors the soil to white rice transfer factor was estimated and found to have the mean value of 4.2 x 10 -3 . The study has shown that the transfer of 210 Pb was retained in the root and its transfer to above ground organs of rice plant is significantly lower. (author)

  16. The phenology of malaria mosquitos in irrigated rice fields in Mali

    NARCIS (Netherlands)

    Klinkenberg, E.; Takken, W.; Huibers, F.P.; Touré, Y.T.

    2003-01-01

    A field study was carried out in the large-scale rice irrigation scheme of the Office du Niger in Mali to investigate the relation between anopheline mosquito larval development and small-scale differences in irrigation practices, such as water level, irrigation application and irrigation frequency.

  17. Water Use and Crop Coefficients in Sprinkler Irrigated Rice

    Directory of Open Access Journals (Sweden)

    Antonino Spanu

    Full Text Available Field experiments were carried out during the years 2002, 2004, 2005 and 2006 to analyze water-soil-atmosphere interactions in sprinkler irrigated rice. The research was carried out in Sardinia (39º 59’ N; 8º 40’ E, at altitude 15 m. The cultivars used in the experiments, respectively in 2002 and in 2004-2005-2006, were Irat 212 and Eurosis. In each year cultivars were subjected to the same crop management. Irrigation was applied since the emergence with the sprinkler method, taking into account the loss of water from ‘Class A’ pan evaporation. Soil water content was monitored at 0.10 m intervals until 1.00-m depth using a ‘Diviner 2000’ (Sentek. In 2002 seven irrigation scheduling treatments were compared. In 2004, 2005, 2006 irrigation treatments provided for optimal soil water conditions during the growing season. In 2002 the results highlighted: 1 0-0.20 m depth was the most important layer for crop water uptake and the best correlated layer with rice rough yield; 2 the positive relationship between yield and water supply was significant until 6500 m3 ha-1 of water applied. Further seasonal irrigation volumes did not increase significantly yield. In 2004, 2005 and 2006 the analysis of the soil water balance at different crop phenological stages allowed to estimate crop coefficients (Kc using the Penman-Monteith equation and the ‘Class A’ pan evaporation (Kcev. Kc varied over the three-year period on average from 0.90 to 1.07 and 0.97, respectively for the emergence-end of tillering, end of tillering-heading and heading-maturing periods, while crop coefficients as a ratio between maximum crop evapotranspiration (ETc and Epan, Kcev ranged from 0.78 to 0.92 and 0.81 for the same time periods.

  18. [Effect of climate change on rice irrigation water requirement in Songnen Plain, Northeast China].

    Science.gov (United States)

    Huang, Zhi-gang; Wang, Xiao-li; Xiao, Ye; Yang, Fei; Wang, Chen-xi

    2015-01-01

    Based on meteorological data from China national weather stations and climate scenario grid data through regional climate model provided by National Climate Center, rice water requirement was calculated by using McCloud model and Penman-Monteith model combined with crop coefficient approach. Then the rice irrigation water requirement was estimated by water balance model, and the changes of rice water requirement were analyzed. The results indicated that either in historical period or in climate scenario, rice irrigation water requirement contour lines during the whole growth period and Lmid period decreased along southwest to northeast, and the same irrigation water requirement contour line moved north with decade alternation. Rice irrigation water requirement during the whole growth period increased fluctuantly with decade alternation at 44.2 mm . 10 a-1 in historical period and 19.9 mm . 10 a-1 in climate scenario. The increase in rice irrigation water requirement during the Lmid period with decade alternation was significant in historical period, but not significant in climate scenario. Contribution rate of climate change to rice irrigation water requirement would be fluctuantly increased with decade alternation in climate scenario. Compared with 1970s, contribution rates of climate change to rice irrigation water requirement were 23.6% in 2000s and 34.4% in 2040s, which increased 14.8 x 10(8) m3 irrigation water in 2000s and would increase 21.2 x 10(8) m3 irrigation water in 2040s.

  19. Varietal improvement of irrigated rice under minimal water conditions

    International Nuclear Information System (INIS)

    Abdul Rahim Harun; Marziah Mahmood; Sobri Hussein

    2010-01-01

    Varietal improvement of irrigated rice under minimal water condition is a research project under Program Research of Sustainable Production of High Yielding Irrigated Rice under Minimal Water Input (IRPA- 01-01-03-0000/ PR0068/ 0504). Several agencies were involved in this project such as Malaysian Nuclear Agency (MNA), Malaysian Agricultural Research and Development Institute (MARDI), Universiti Putra Malaysia (UPM) and Ministry of Agriculture (MOA). The project started in early 2004 with approved IRPA fund of RM 275,000.00 for 3 years. The main objective of the project is to generate superior genotypes for minimal water requirement through induced mutation techniques. A cultivated rice Oryza sativa cv MR219 treated with gamma radiation at 300 and 400 Gray were used in the experiment. Two hundred gm M2 seeds from each dose were screened under minimal water stress in greenhouse at Mardi Seberang Perai. Five hundred panicles with good filled grains were selected for paddy field screening with simulate precise water stress regime. Thirty eight potential lines with required adaptive traits were selected in M3. After several series of selection, 12 promising mutant line were observed tolerance to minimal water stress where two promising mutant lines designated as MR219-4 and MR219-9 were selected for further testing under several stress environments. (author)

  20. Characterization of mercury species in brown and white rice (Oryza sativa L.) grown in water-saving paddies

    Energy Technology Data Exchange (ETDEWEB)

    Rothenberg, Sarah E., E-mail: rothenberg.sarah@gmail.com [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Feng Xinbin, E-mail: fengxinbin@vip.skleg.cn [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Dong Bin, E-mail: dongbin@whu.edu.cn [State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072 (China); Shang Lihai, E-mail: shanglihai@vip.gyig.ac.cn [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Yin Runsheng, E-mail: yinrunsheng2002@163.com [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Yuan Xiaobo, E-mail: xiantao_131@163.com [College of Resources and the Environment, Southwest University, Chongqing 400716 (China)

    2011-05-15

    In China, total Hg (Hg{sub T}) and methylmercury (MeHg) were quantified in rice grain grown in three sites using water-saving rice cultivation methods, and in one Hg-contaminated site, where rice was grown under flooded conditions. Polished white rice concentrations of Hg{sub T} (water-saving: 3.3 {+-} 1.6 ng/g; flooded: 110 {+-} 9.2 ng/g) and MeHg (water-saving 1.3 {+-} 0.56 ng/g; flooded: 12 {+-} 2.4 ng/g) were positively correlated with root-soil Hg{sub T} and MeHg contents (Hg{sub T}: r{sup 2} = 0.97, MeHg: r{sup 2} = 0.87, p < 0.05 for both), which suggested a portion of Hg species in rice grain was derived from the soil, and translocation of Hg species from soil to rice grain was independent of irrigation practices and Hg levels, although other factors may be important. Concentrations of Hg{sub T} and other trace elements were significantly higher in unmilled brown rice (p < 0.05), while MeHg content was similar (p > 0.20), indicating MeHg infiltrated the endosperm (i.e., white rice) more efficiently than inorganic Hg(II). - Highlights: > First time that Hg{sub T} and MeHg were characterized in both brown and white rice. > MeHg translocation into the endosperm was more efficient than inorganic Hg(II). > In this respect, MeHg behaved like dimethylarsinic acid and organic Se species. > In white rice, Hg{sub T} and MeHg were positively correlated with soil Hg{sub T} and MeHg. > Uptake rates of Hg{sub T} and MeHg were independent of irrigation methods and Hg content. - Methylmercury was more efficiently translocated to the endosperm than inorganic mercury.

  1. Growth and Flowering Responses of Cut Chrysanthemum Grown under Restricted Root Volume to Irrigation Frequency

    Directory of Open Access Journals (Sweden)

    Viyachai Taweesak

    2014-01-01

    Full Text Available Influences of irrigation frequency on the growth and flowering of chrysanthemum grown under restricted root volume were tested. Chrysanthemum cuttings (Chrysanthemum morifolium “Reagan White” were grown in seedling tray which contained coconut peat in volumes of 73 and 140 cm3. Plants were irrigated with drip irrigation at irrigation frequencies of 4 (266 mL, 6 (400 mL, and 8 (533 mL times/day to observe their growth and flowering performances. There was interaction between irrigation frequency and substrate volume on plant height of chrysanthemum. Plants grown in 140 cm3 substrates and irrigated 6 times/day produced the tallest plant of 109.25 cm. Plants irrigated 6 and 8 times/day had significantly higher level of phosphorus content in their leaves than those plants irrigated 4 times/day. The total leaf area, number of internodes, leaf length, and leaf width of chrysanthemums grown in 140 cm3 substrate were significantly higher than those grown in 73 cm3 substrate. The numbers of flowers were affected by both irrigation frequencies and substrate volumes. Chrysanthemums irrigated 8 times/day had an average of 19.56 flowers while those irrigated 4 times/day had an average of 16.63 flowers. Increasing irrigation frequency can improve the growth and flowering of chrysanthemums in small substrate volumes.

  2. Evaluation of Different Rice Genotypes Tolerance to Saline Irrigation Water

    Directory of Open Access Journals (Sweden)

    S. Jafari Rad

    2015-12-01

    Full Text Available To study the responses of seven rice genotypes (Khazar, SA13, Deylam, Sange Joe, Sepidrud, 831 and T5 to different levels of irrigation water salinity, and determining grain yield based on tolerance indices, a CRD based factorial pot experiment with five levels of irrigation water salinity (1, 2, 4, 6 and 8 dSm-1 and three replications was carried out at Rice Research Institute of Iran in 2011. Indices such as SSI, TOL, MP, GMP, HM, STI, YI and YSI were calculated and their correlations with grain yield were estimated for both stress and non-stress conditions. Results indicated significant differences among genotypes and the indices within both conditions. Results also showed that STI and MP indices could be considered as the best indices to screen salt tolerant genotypes. Among the genotypes used in the experiment, T5 produced the highest yield in both non-stress (19.71 g/plant and stress (10.69 g/plant conditions, while the lowest yield in normal (11.84 g/plant and stressful (4.29 g/plant conditions was recorded for Deylam and Khazar, respectively. The highest and the lowest percentage of yield reduction were found in Khazar (69.49% and Sange Joe (31.48% in stressful conditions, respectively. Overall, genotypes T5, 831, Sepidrud and Sange Joe can probably be considered as superior high yielding genotypes in both saline and non-saline conditions for further research.

  3. Rice agroecosystem of the Muda irrigation scheme, Malaysia

    International Nuclear Information System (INIS)

    Nashriyah Mat; Ho Nai Kin; Ismail Sahid; Ahyaudin Ali; Lum Keng Yeang

    1998-01-01

    Pesticides have become one of the major components of modern farming practice. However, their usage needs to be properly carried out and regulated. Farmers need to be aware of the potential hazards arising out of improper use of pesticides, to them as well to the environment. This book presents the results of a comprehensive study on the impact of pesticide usage in the largest rice agroecosystem in Malaysia, the Muda Irrigation Scheme. The study, carried out by a group of local scientists, covers the impact of pesticide usage on biodiversity and bioresources (forest, weed, insect, fish and bird). In addition to farmers education, it shows the potential of crop establishment, irrigation method and double cropping of rice as useful factors that can be employed in minimizing the impact. The book also provides good foundation for future work and points out areas for further studies. It is a valuable reference to policy makers, researchers, regulators, agriculture-related agencies, chemical / fertilizer companies as well as those concerned with sustainable farming. The ecologists, chemists, biochemists, entomologists, zoologists, botanists, microbiologists, agronomists and medical practitioners involved in this study are congratulated for their efforts. (Nahrul Khair Alang Md Rashid)

  4. Rice agroecosystem of the Muda irrigation scheme, Malaysia

    Energy Technology Data Exchange (ETDEWEB)

    Mat, Nashriyah [Malaysian Institute for Nuclear Technology Research MINT, Bangi (Malaysia); Kin, Ho Nai [Muda Agricultural Development Authority MADA, Alor Setar (Malaysia); Sahid, Ismail [Universiti Kebangsaan Malaysia, Bangi (Malaysia); Ali, Ahyaudin [Universiti Sains Malaysia, Penang (Malaysia); Yeang, Lum Keng [Malaysian Agricultural Research and Development Institute, Serdang (Malaysia)

    1998-07-01

    Pesticides have become one of the major components of modern farming practice. However, their usage needs to be properly carried out and regulated. Farmers need to be aware of the potential hazards arising out of improper use of pesticides, to them as well to the environment. This book presents the results of a comprehensive study on the impact of pesticide usage in the largest rice agroecosystem in Malaysia, the Muda Irrigation Scheme. The study, carried out by a group of local scientists, covers the impact of pesticide usage on biodiversity and bioresources (forest, weed, insect, fish and bird). In addition to farmers education, it shows the potential of crop establishment, irrigation method and double cropping of rice as useful factors that can be employed in minimizing the impact. The book also provides good foundation for future work and points out areas for further studies. It is a valuable reference to policy makers, researchers, regulators, agriculture-related agencies, chemical / fertilizer companies as well as those concerned with sustainable farming. The ecologists, chemists, biochemists, entomologists, zoologists, botanists, microbiologists, agronomists and medical practitioners involved in this study are congratulated for their efforts. (Nahrul Khair Alang Md Rashid)

  5. Yield loss and economic thresholds of yellow nutsedge in irrigated rice as a function of the onset of flood irrigation

    Directory of Open Access Journals (Sweden)

    Nixon da Rosa Westendorff

    2014-03-01

    Full Text Available Yellow nutsedge (Cyperus esculentus is adapted to flooding and reduces yield in irrigated rice. Information on the competitive ability of this weed with the crop and the size of the economic damage caused is lacking. Mathematical models quantify the damage to crops and support control decision-making. This study aimed to determine yield losses and economic thresholds (ET of this weed in the culture according to weed population and time of onset of irrigation of the crop. The field study was conducted in the agricultural year of 2010/2011 in Pelotas/RS to evaluate the competitive ability of BRS Querência in competition with different population levels of yellow nutsedge and two periods of onset of flood irrigation (14 and 21 days after emergence. The hyperbolic model satisfactorily estimated yield losses caused by yellow nutsedge. Population of yellow nutsedge was the variable most fitted to the model. The delay of seven days for the beginning of rice irrigation causes decrease in competitive ability of BRS Querência, and based on the ET calculated to the price paid for rice, it is necessary between two and thirteen plants m-2 weed to justify the control in the first and second period of irrigation, respectively. Increases in yield, price paid for rice and control efficiency of the herbicide, besides reduction of costs of controlling promote reduction of ET of yellow nutsedge in rice crops, justifying the adoption of control measures even at smaller weed population.

  6. Heavy metals in Australian grown and imported rice and vegetables on sale in Australia: health hazard.

    Science.gov (United States)

    Rahman, M Azizur; Rahman, Mohammad Mahmudur; Reichman, Suzie M; Lim, Richard P; Naidu, Ravi

    2014-02-01

    Dietary exposure to heavy metals is a matter of concern for human health risk through the consumption of rice, vegetables and other major foodstuffs. In the present study, we investigated concentrations of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) in Australian grown and imported rice and vegetables on sale in Australia. The mean concentrations of Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn in Australian grown rice were 7.5 µg kg(-1), 21 µg kg(-1), 144 µg kg(-1), 2.9 mg kg(-1), 24.4 mg kg(-1), 166 µg kg(-1), 375 µg kg(-1), and 17.1 mg kg(-1) dry weight (d. wt.), respectively. Except Cd, heavy metal concentrations in Australian grown rice were higher than Bangladeshi rice on sale in Australia. However, the concentrations of Cd, Cr, Cu, and Ni in Indian rice on sale in Australia were higher than Australian grown rice. The concentrations of Cu and Ni in Vietnamese rice, and that of Cd, Cr, Cu, Ni, and Pb in Thai rice on sale in Australia were also higher than Australian grown rice. Heavy metal concentrations in Pakistani rice on sale in Australia were substantially lower than that in Australian grown rice. In Australian grown rice varieties, the concentrations of heavy metals were considerably higher in brown rice varieties than white rice varieties, indicating Australian brown rice as a potential source of dietary heavy metals for Australian consumers. The mean concentrations of heavy metals in Australian grown and Bangladeshi vegetables on sale in Australia were also determined. Some of the Australian grown and Bangladeshi vegetables contained heavy metals higher than Australian standard maximum limits indicating them as potential sources of dietary heavy metals for Australian consumers. Further investigation is required to estimate health risks of heavy metals from rice and vegetables consumption for Australian consumers. © 2013 Published by Elsevier Inc.

  7. Soma térmica de algumas fases do ciclo de desenvolvimento da escala de COUNCE para cultivares Sul-Brasileiras de arroz irrigado Thermal time of some developmental phases of the COUNCE scale for irrigated rice cultivars grown in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Nereu Augusto Streck

    2007-01-01

    Full Text Available A escala de COUNCE é uma escala de desenvolvimento de arroz recente que vem sendo gradativamente adotada no Brasil. No entanto, a duração das fases em ºC dia dessa escala ainda não está disponível para as cultivares brasileiras de arroz irrigado. Sendo assim, o objetivo deste trabalho foi determinar a soma térmica de algumas fases do ciclo de desenvolvimento da escala de COUNCE para cultivares Sul-Brasileiras de arroz irrigado, utilizando-se diversos métodos de cálculo e diferentes temperaturas cardinais ao longo do ciclo de desenvolvimento. Um experimento a campo foi desenvolvido em Santa Maria, RS, durante dois anos agrícolas (2003/2004 e 2004/2005 e com cinco épocas de semeadura em cada um deles. O delineamento experimental foi o inteiramente casualizado com quatro repetições. Cada repetição consistia de um vaso de 12 litros com 10 plantas. As datas dos estágios de desenvolvimento R2 (aparecimento do colar da folha bandeira e R9 (todos os grãos com casca marrom da escala de COUNCE foram registradas no colmo principal de cinco plantas por vaso. As cultivares utilizadas foram IRGA 421, IRGA 416, IRGA 417, IRGA 420, BR-IRGA 409, BRS 7 TAIM e EPAGRI 109. Considerando-se as temperaturas cardinais de 11 °C, 28 °C e 40 °C, a soma térmica para completar a fase emergência-R2 foi de 700-800 °C dia na cultivar muito precoce, 1000-1400 °C dia nas cultivares precoces e 1300-1700 °C dia nas cultivares médias e tardia, e a soma térmica para completar a fase R2-R9 foi de 400-700 °C dia e sem relação com o ciclo da cultivar.The COUNCE scale is a developmental scale recently proposed for rice and that is being used in Brazil. However, the duration of developmental phases of this scale in degree-days is not available for Brazilian irrigated rice cultivars. Thus, the objective of this study was to determine the thermal time of some developmental phases of the COUNCE scale in irrigated rice cultivars grown in Southern Brazil using

  8. Effect of saline irrigation water on yield and yield components of rice ...

    African Journals Online (AJOL)

    vaio

    2013-05-29

    May 29, 2013 ... levels at different growth stages of rice on yield and its components. Treatments included ... Therefore, irrigation with saline water at the early growth stages has more negative effect on ...... diversification. Land Degrad. Dev.

  9. Actual and potential salt-related soil degradation in an irrigated rice scheme in the Sahelian zone of Mauritania

    NARCIS (Netherlands)

    Asten, van P.J.A.; Barbi'ro, L.; Wopereis, M.C.S.; Maeght, J.L.; Zee, van der S.E.A.T.M.

    2003-01-01

    Salt-related soil degradation due to irrigation activities is considered a major threat to the sustainability of rice cropping under semi-arid conditions in West Africa. Rice productivity problems related to soil salinity, alkalinity and topographic position were observed in an irrigated rice scheme

  10. Reducing Potential Disaster Impacts in Irrigated Rice Fields in West Java

    NARCIS (Netherlands)

    Sianturi, R.S.

    2018-01-01

    The increasing global population inevitably demands for stable food production. As an important food crop, rice plays a major role in maintaining food security. However, irrigated rice fields are increasingly suffered from natural hazard occurrences worldwide, disrupting livelihoods of millions of

  11. Climate Change Implications to Irrigated Rice Production in Southern Brazil: A Modelling Approach

    Science.gov (United States)

    Dos Santos, Thiago

    Rice is one of the staple foods for more than three billion people worldwide. When cultivated under irrigated conditions (i.e. lowland rice), rice is one of the most intensive water consumer crops globally. Therefore, representation of rice growth should be integrated into the latest land surface models to allow studies on food security and to ensure that accurate simulations of the bidirectional feedbacks between the land surface and atmosphere take place. In this study, I present a new process-based model for rice fields that includes rice growth and rice irrigation as modules within the Agro-IBIS dynamic agro-ecosystem model. The model includes a series of equations, agricultural management parameters and an irrigation scheme that are specifically tailored for rice crops. The model was evaluated against leaf area index and biomass observations, obtained for one growing season in Rio Grande do Sul state (southern Brazil), and in Los Banos, Philippines. The model accurately captured the temporal dynamics of leaf area index in both the Brazilian and the Philippine sites, and predicted end-of-season biomass with an error of between -9.5% and 11.3% depending on the location and the plant organ. Rice phenology is predicted by the model based on experimentally-derived growth rates, and was evaluated by comparing simulated and observed durations of the four growth phases considered by the model. Agro-IBIS showed a tendency to overestimate the duration of the growth stages between 3% and 16%, but underestimated by 8% the duration of the panicle formation phase in one growing season. The new irrigation model is based on the water balance at the surface and applies irrigation in order to keep the water layer at the paddy field always in the optimum level. A set of climate projections from global climate models under two emission scenarios, and excluding and considering CO2 fertilizations effects, was used to drive the updated Agro-IBIS to estimate the effects of climate

  12. Irrigated cotton grown on sierozem soils in South Kazakhstan

    Science.gov (United States)

    The Gloldnaya steppe has large areas of fertile sierozem soils that are important for crop production and its accompanying economic development. The soils are fertile loams but because of the steppe’s dry environment, they need to be irrigated. Our objective was to study irrigation management of cot...

  13. Selectivity and weed control efficacy of some herbicides applied to sprinkler irrigated rice (Oryza sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Cavero, J; Zaragoza, C; Cirujeda, A; Anzalone, A; Faci, J M; Blanco, O

    2011-07-01

    Sprinkler irrigation can reduce the irrigation water needed to grow rice. However, most available information on weed control with herbicides is related to flood irrigated rice because this is the main growing method. Field experiments were conducted at Zaragoza (Spain) during two years to study weed control and tolerance of sprinkler irrigated rice to several herbicides. The main weeds were Atriplex prostrata Boucher ex DC., Cyperus rotundus L., Echinochloa crus-galli (L.) Beauv. and Sonchus oleraceus L. Rice cv Guadiamar was tolerant to preemergence (PRE) application of clomazone at 0.36 kg ha{sup -}1 and oxadiazon at 0.5 kg ha{sup -}1. PRE application of pendimethalin at 1.32 kg ha{sup -}1 combined with clomazone at 0.36 kg ha{sup -}1 decreased rice yield. Postemergence (POST) application of bentazon at 1.6 kg ha{sup -}1 + MCPA at 0.25 kg ha{sup -}1 did not injure rice but POST application of azimsulfuron at 0.025 kg ha{sup -}1 produced visual crop injury. Only treatments that controlled grassy weeds since rice was planted and by more than 80% at harvest time lead to acceptable rice yield (> 5,000 kg ha{sup -}1). Clomazone applied PRE at 0.36 kg ha{sup -}1 provided good control of grassy weeds (> 80%) and the highest rice yield, so it is recommended as a selective and efficacious PRE treatment for weed control of annual weeds in sprinkler irrigated rice. The perennial purple nutsedge was difficult to control at high plant densities (> 150 plants m{sup -}2) and the recommended herbicide is azimsulfuron applied at POST at 0.02 kg ha{sup -}1. (Author) 37 refs.

  14. Adubarroz: a brazilian experience for fertilization and liming recommendation of irrigated rice via computational system

    Directory of Open Access Journals (Sweden)

    Felipe de Campos Carmona

    Full Text Available ABSTRACT: Recommendations for fertilizing irrigated rice in southern Brazil have been constantly evolving over years. In this process, the influence of factors such as the development cycle of varieties and sowing period increased. Thus, computational tools that take these and others important aspects into account can potentiate the fertilization response of rice. This study describes the computer program "ADUBARROZ". The software provides recommendations of fertilizer rates and liming requirements of irrigated rice, based on information entered by the user. The system takes various factors that regulate the crop response to fertilization into account. A final report is established with the graphical representation of input management over time.

  15. Rice production with minimal irrigation and no nitrogen fertilizer by intensive use of treated municipal wastewater.

    Science.gov (United States)

    Muramatsu, Ayumi; Watanabe, Toru; Sasaki, Atsushi; Ito, Hiroaki; Kajihara, Akihiko

    2014-01-01

    We designed a new cultivation system of rice with circulated irrigation to remove nitrogen from treated municipal wastewater effectively and assessed the possibility of nitrogen removal in the new system without any adverse effects on rice production through bench-scale experiments through two seasons. Overgrowth of the rice plant, which can lead to lodging and tasteless rice, was found in the first season probably because nitrogen supply based on standard practice in normal paddy fields was too much in the closed irrigation system. In the second season, therefore, the amount of treated wastewater initially applied to the system was reduced but this resulted in a considerably decreased yield. On the other hand, the taste of the rice was significantly improved. The two-season experiments revealed that the new system enabled rice production with minimal irrigation (approximately 50% on the yield base compared to normal paddy fields) and no nitrogen fertilizer. The system also achieved >95% removal of nitrogen from the treated wastewater used for circulated irrigation. The accumulation of harmful metals in the rice was not observed after one season of cultivation in the new system. The accumulation after cultivation using the same soil repeatedly for a longer time should be examined by further studies.

  16. THE EFFECT OF RICE CULTIVARS ON METHANE EMISSION FROM IRRIGATED RICE FIELD

    Directory of Open Access Journals (Sweden)

    P. Setyanto

    2016-10-01

    Full Text Available Rice plants have been reported to affect methane (CH4 emission from rice fields. The objectives of this study were to determine the effect of rice cultivars on CH4 emission from flooded rice and to develop crop management strategies with low emitting rice cultivars while sustaining high yield. The four rice cultivars studied were Memberamo, Cisadane, IR64, and Way Apoburu. The CH4 emissions were determined in the wet season of 2001/2002 (November-February using an automated closed chamber technique in an irrigated field condition. Farmyard manure at the rate of 5 t ha-1 was given to the plots to ensure carbon was not limited. Root weight, root length, biomass, and number of tillers were determined at 17, 36, and 57 days after transplanting (DAT. The results showed that the mean CH4 emission was highest in the plot planted with Cisadane (94.8 kg CH4 ha-1, and the lowest with IR64 (37.7 kg CH4 ha-1. The plots treated with emberamo and Way Apoburu resulted an intermediate CH4 emission at the average of 61.1 and 58.9 kg CH4 ha-1, respectively. There was no significant difference in yield between the cultivars tested. The yield of Memberamo, Cisadane, IR64, and Way Apoburu were 5.882, 5.764, 5.873 and 6.065 t ha-1, respectively. Statistical analysis showed that there were no significant differences in the root weight and root length among cultivars. However, Cisadane gave the highest dry matter weight (222 g hill-1 at 57 DAT compared to the other cultivars (175-190 g hill-1. Plant tillers did not show significant differences between the cultivars. Regression analysis showed that CH4 flux was significantly related with root weight, root length, aboveground biomass, and number of plant tillers. This finding shows that the use of selected cultivars, such as IR64, can potentially lower CH4 emission without scarifying yield.

  17. Effects of Furrow Irrigation on the Growth, Production, and Water Use Efficiency of Direct Sowing Rice

    Directory of Open Access Journals (Sweden)

    Chunlin He

    2010-01-01

    Full Text Available Rice farming is the major crop production in Asia and is predicted to increase significantly in the near future in order to meet the demands for the increasing human population. Traditional irrigation methods used in rice farming often result in great water loss. New water-saving methods are urgently needed to reduce water consumption. Three field and pot experiments were conducted to evaluate the furrow irrigation (FI system to improve water use efficiency (WUE and production of direct sowing rice in southern China. Compared to the conventional irrigation (CI system (continuous flooding irrigation, for every square hectometer of rice field, the FI system reduced water use by 3130 m3, or 48.1%, and increased grain production by 13.9% for an early cultivar. For a late cultivar, the FI system reduced water use by 2655 m3, or 40.6%, and an increase of grain production by 12.1%. The improved WUE in the FI system is attributed to (1 a significant reduction of irrigation rate, seepage, evaporation, and evapotranspiration; (2 a significant reduction in the reduced materials, such as ferrous ion (Fe2+, and therefore an increase in the vitality of the root system, evident by the increases in the number of white roots by 32.62%, and decreases in the number of black roots by 20.04% and yellow roots by 12.58%; the use of the FI system may also reduce humidity of the rice field and enhance gas transport in the soil and light penetration, which led to reduced rice diseases and increased leaf vitality; and (3 increases in tiller and effective spikes by 11.53% and the weight per thousand grains by 1.0 g. These findings suggest that the shallow FI system is a promising means for rice farming in areas with increasing water shortages.

  18. Effects of furrow irrigation on the growth, production, and water use efficiency of direct sowing rice.

    Science.gov (United States)

    He, Chunlin

    2010-08-03

    Rice farming is the major crop production in Asia and is predicted to increase significantly in the near future in order to meet the demands for the increasing human population. Traditional irrigation methods used in rice farming often result in great water loss. New water-saving methods are urgently needed to reduce water consumption. Three field and pot experiments were conducted to evaluate the furrow irrigation (FI) system to improve water use efficiency (WUE) and production of direct sowing rice in southern China. Compared to the conventional irrigation (CI) system (continuous flooding irrigation), for every square hectometer of rice field, the FI system reduced water use by 3130 m3, or 48.1%, and increased grain production by 13.9% for an early cultivar. For a late cultivar, the FI system reduced water use by 2655 m3, or 40.6%, and an increase of grain production by 12.1%. The improved WUE in the FI system is attributed to (1) a significant reduction of irrigation rate, seepage, evaporation, and evapotranspiration; (2) a significant reduction in the reduced materials, such as ferrous ion (Fe2+), and therefore an increase in the vitality of the root system, evident by the increases in the number of white roots by 32.62%, and decreases in the number of black roots by 20.04% and yellow roots by 12.58%; the use of the FI system may also reduce humidity of the rice field and enhance gas transport in the soil and light penetration, which led to reduced rice diseases and increased leaf vitality; and (3) increases in tiller and effective spikes by 11.53% and the weight per thousand grains by 1.0 g. These findings suggest that the shallow FI system is a promising means for rice farming in areas with increasing water shortages.

  19. Genetic diversity of high performance cultivars of upland and irrigated Brazilian rice.

    Science.gov (United States)

    Coelho, G R C; Brondani, C; Hoffmann, L V; Valdisser, P A M R; Borba, T C O; Mendonça, J A; Rodrigues, L A; de Menezes, I P P

    2017-09-21

    The objective of this study was to analyze the diversity and discrimination of high-performance Brazilian rice cultivars using microsatellite markers. Twenty-nine rice cultivars belonging to EMBRAPA Arroz e Feijão germplasm bank in Brazil were genotyped by 24 SSR markers to establish their structure and genetic discrimination. It was demonstrated that the analyzed germplasm of rice presents an expressive and significant genetic diversity with low heterogeneity among the cultivars. All 29 cultivars were differentiated genetically, and were organized into two groups related to their upland and irrigated cultivation systems. These groups showed a high genetic differentiation, with greater diversity within the group that includes the cultivars for irrigated system. The genotyping data of these cultivars, with the morphological e phenotypical data, are valuable information to be used by rice breeding programs to develop new improved cultivars.

  20. Contamination of rice (Oryza sativa L) with Cadmium and Arsenic by irrigation with the Bogota River water in rice soils of the Lower Basin

    International Nuclear Information System (INIS)

    Montenegro, Omar; Mejia L

    2001-01-01

    In this study, field and greenhouse experiments were simultaneously carried out with rice (oryza sativa l., variedad oryzica-1) in soils of the Bogota River lower basin (Los Manueles Series, a member of the clayed, mixed, isohipertermic family of the Fluventic Vertic Haplustepts) to evaluate the effect of Cd and As content of the irrigation waters (of the Bogota River and greenhouse) on soils and: 1) rice growth physiological parameters; 2) Cd and As accumulated in different parts of rice plants; 3) yields and other aspects and properties of rice crop. The results lead to the following conclusions: 1) The Cd and As content of the Bogota River water, increased during the driest months and was minimum in those with the highest precipitation; Cd and As concentrations in both seasons surpassed the maximum permissible limits. 2) Rice height was highest when irrigation water does have neither Cd nor As. Effects of both elements showed an inverse lineal tendency. 3) The gradual increase of Cd in irrigation water reduced in 12.5% the number of grains per panicle; the increase of As induced a 10% reduction. 4) The highest concentration of Cd and As in irrigation waters significantly reduced yields; maximum yields l were obtained when Cd and As were absent from irrigation waters. 5) For any concentration of As in irrigation water the highest concentration of Cd was accumulated in rice leafs when concentration of Cd 2 was 2mg/l; above this value Cd accumulation in leafs el decreased with the gradual increase of As concentration. 6) Cd and As accumulated in rice grains increased with the gradual increment of both elements in the irrigation waters; Cd and As accumulated were respectively 50 and 15 times higher than the maximum critical levels proposed for rice grains. 7) Cd and As accumulated progressively on soils with gradual increase of both elements in irrigation waters 8) Cd and As concentration in irrigation waters apparently does not affect the rice mill behavior

  1. Simulation of rice yield under different irrigation and nitrogen application managements by CropSyst model

    Directory of Open Access Journals (Sweden)

    Narjes ZARE

    2015-12-01

    Full Text Available The aim of this study was the calibration and validation of CropSyst model for rice in the city of Rasht. The necessary data were extracted from a field experiment which was carried out during 2005-2007 in a split-plot design. The main plots were irrigation regimes including continuous flooding irrigation and 5-day irrigation intervals. The subplots consisted of four nitrogen levels: zero N application, 45, 60 and 75 kg N ha-1. Normalized Root Mean Squared Error (nRMSE and Residual Mass Coefficient (Crm in calibration years were 9.3 % and 0.06, respectively. In validation year, nRMSE and Crm were 9.7 % and 0.11, respectively. According to other indices to assess irrigation regimes and fertilizer levels, the most suitable treatments regarding environmental aspect were 5-day irrigation regime and 45 kg N ha-1.

  2. Effects of compost on soil fertility in irrigated rice growing at Kou ...

    African Journals Online (AJOL)

    Effects of compost on soil fertility in irrigated rice growing at Kou Valley (Burkina Faso) : Amélioration de la fertilité du sol par utilisation du compost en riziculture irriguée dans la Vallée du Kou au Burkina Faso.

  3. Management systems in irrigated rice affect physical and chemical soil properties

    NARCIS (Netherlands)

    Rodrigues de Lima, A.C.; Hoogmoed, W.B.; Pauletto, E.A.; Pinto, L.F.S.

    2009-01-01

    Lowland soils are commonly found in the state of Rio Grande do Sul, Southern of Brazil, where they represent around 20% of the total area. Deficient drainage is the most important natural characteristic of these soils which therefore are mainly in use for irrigated rice (Oriza sativa). Degradation

  4. Using farmer knowledge to combat low productive spots in rice fields of a Sahelian irrigation scheme

    NARCIS (Netherlands)

    Asten, van P.J.A.; Barro, S.E.; Wopereis, M.C.S.; Defoer, T.

    2004-01-01

    In the oldest sections of Burkina Faso's largest irrigation scheme in the Sourou Valley (13degrees 10'N, 03degrees 30'W) rice (Oryza sativa L.) yields dropped from about 5 to 6 t ha(-1) in the early 1990s, shortly after establishment of the scheme, to 2 to 4 t ha(-1) from 1995 onwards. Farmers

  5. Agronomic and environmental aspects of diazotrophic bacteria in irrigated rice fields

    Science.gov (United States)

    This article provides an overview of the free-living and plant-associated nitrogen-fixing bacterial communities in irrigated rice fields, with a focus on describing the drivers affecting community assemblages in this soil-water-plant-atmosphere system. Theoretical and technical advances in non-legu...

  6. Rice production with less irrigation water is possible in a Sahelian environment

    NARCIS (Netherlands)

    Vries, de M.E.; Rodenburg, J.; Bado, B.V.; Sow, A.; Leffelaar, P.A.; Giller, K.E.

    2010-01-01

    We investigated the possibility of saving irrigation water in rice production in a Sahelian environment with different nitrogen rates and weed control treatments. A series of field experiments was conducted at Ndiaye (shallow water table, dry and wet season) and at Fanaye (deep water table, wet

  7. Interaction of different irrigation strategies and soil textures on the nitrogen uptake of field grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, S.H.; Andersen, Mathias Neumann; Lærke, Poul Erik

    2011-01-01

    Nitrogen (N) uptake (kg ha-1) of field-grown potatoes was measured in 4.32 m2 lysimeters that were filled with coarse sand, loamy sand, and sandy loam and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. PRD and DI as water-saving irrigation treatments...... in the loamy sand had the highest amount of N uptake. The interaction between irrigation treatments and soil textures was significant, and implied that under non-limiting water conditions, loamy sand is the suitable soil for potato production because plants can take up sufficient amounts of N and it could...... potentially lead to higher yield. However, under limited water conditions and applying water-saving irrigation strategies, sandy loam and coarse sand are better growth media because N is more available for the potatoes. The simple yield prediction model was developed that could explains ca. 96...

  8. mathematical model for scheduling irrigation for swamp rice in port

    African Journals Online (AJOL)

    2017-03-24

    Mar 24, 2017 ... The thirst for increased food production and management of our natural resources (water) .... 16th, 2009. .... formula, Karl Pearson, (1980), was adopted in ..... Hawksworth, D. L., 1985. Foreword. In S.H. Ou, ed. Rice diseases.

  9. Root morphology, hydraulic conductivity and plant water relations of high-yielding rice grown under aerobic conditions.

    Science.gov (United States)

    Kato, Yoichiro; Okami, Midori

    2011-09-01

    Increasing physical water scarcity is a major constraint for irrigated rice (Oryza sativa) production. 'Aerobic rice culture' aims to maximize yield per unit water input by growing plants in aerobic soil without flooding or puddling. The objective was to determine (a) the effect of water management on root morphology and hydraulic conductance, and (b) their roles in plant-water relationships and stomatal conductance in aerobic culture. Root system development, stomatal conductance (g(s)) and leaf water potential (Ψ(leaf)) were monitored in a high-yielding rice cultivar ('Takanari') under flooded and aerobic conditions at two soil moisture levels [nearly saturated (> -10 kPa) and mildly dry (> -30 kPa)] over 2 years. In an ancillary pot experiment, whole-plant hydraulic conductivity (soil-leaf hydraulic conductance; K(pa)) was measured under flooded and aerobic conditions. Adventitious root emergence and lateral root proliferation were restricted even under nearly saturated conditions, resulting in a 72-85 % reduction in total root length under aerobic culture conditions. Because of their reduced rooting size, plants grown under aerobic conditions tended to have lower K(pa) than plants grown under flooded conditions. Ψ(leaf) was always significantly lower in aerobic culture than in flooded culture, while g(s) was unchanged when the soil moisture was at around field capacity. g(s) was inevitably reduced when the soil water potential at 20-cm depth reached -20 kPa. Unstable performance of rice in water-saving cultivations is often associated with reduction in Ψ(leaf). Ψ(leaf) may reduce even if K(pa) is not significantly changed, but the lower Ψ(leaf) would certainly occur in case K(pa) reduces as a result of lower water-uptake capacity under aerobic conditions. Rice performance in aerobic culture might be improved through genetic manipulation that promotes lateral root branching and rhizogenesis as well as deep rooting.

  10. Soil Suitability Classification of Tomas Irrigation Scheme for Irrigated ...

    African Journals Online (AJOL)

    The need for sustainable rice production in Nigeria cannot be over-emphasized. Since rice can be grown both under rain-fed and irrigated conditions, the need for soil suitability evaluation becomes very necessary in order for supply to meet up with demand. Six land qualities viz; climate, soil physical properties, drainage, ...

  11. Temporal changes of radiocesium in irrigated paddy fields and its accumulation in rice plants in Fukushima.

    Science.gov (United States)

    Yang, Baolu; Onda, Yuichi; Wakiyama, Yoshifumi; Yoshimura, Kazuya; Sekimoto, Hitoshi; Ha, Yiming

    2016-01-01

    About half of the total paddy field area, which is the dominant agricultural land in Fukushima Prefecture, was contaminated by radiocesium released by the Fukushima Daiichi Nuclear Power Plant accident. In this study, we investigated the temporal changes of radiocesium in soil, irrigation water, and rice plant in two adjacent rice paddies, with and without surface-soil-removal, in Fukushima Prefecture for over three years (2012-2014) after the nuclear accident. Our results showed that radiocesium migrated into 24-28 cm soil layers and that the activity concentration of radiocesium in paddy soils showed a significant reduction in 2014. The newly added radiocesium to paddies through irrigation water contributed only a maximum value of 0.15% and 0.75% of the total amount present in control and decontaminated paddies, respectively, throughout the study period. The radiocesium activity concentration in suspended sediment in irrigation water exponentially decreased, and the effective half-lives (Teff) for (137)Cs and (134)Cs were 1.3 and 0.9 years, respectively. Additionally, the average suspended sediment concentration in irrigation water increased between 2012 and 2014, suggesting that enhanced soil erosion had occurred in the surrounding environment. Radiocesium accumulation in rice plant also decreased with time in both paddies. However, the concentration ratio of radiocesium for rice plant in the decontaminated paddy increased compared with control paddy, despite approximately 96% of fallout radiocesium removed in paddy soil. Further analysis is required to clarify the reasons of high concentration ratio of radiocesium for rice plant in the decontaminated paddy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Scaling up Intermittent Rice Irrigation for Malaria Control on the ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The research aims to foster uptake of intermittent irrigation at the watershed level (Valle de Jequetepeque in La Libertad) by exploring ways to: - disseminate knowledge and skills (farmer-to-farmer agricultural extension); - assess and document social, health, environmental, and economic trade-offs as farmers adopt new ...

  13. Land Evaluation for improved Rice Production in Watari Irrigation ...

    African Journals Online (AJOL)

    ... suggested to overcome these limitation and upgrade the suitability of the mapping units for increased rice production are; application of inorganic fertilizer, improve the low levels of nutrients and organic matter contents of the soil in the area and other recommendations include land leveling and conservation measures to ...

  14. Interaction of genotype x management on vegetative growth and weed suppression of aerobic rice

    NARCIS (Netherlands)

    Zhao, D.L.; Bastiaans, L.; Atlin, G.N.; Spiertz, J.H.J.

    2007-01-01

    Water shortage in drought-prone rice-growing areas of the world is threatening conventional irrigated rice production systems, in which rice is transplanted into fields where standing water is maintained until harvest. Aerobic rice production systems, in which rice is grown as a direct-seeded upland

  15. AN INTERACTION MODEL BETWEEN ENVIRONMENTAL FACTORS AND BLACK RICE GROWTH IN IRRIGATED ORGANIC PADDY FIELD

    Directory of Open Access Journals (Sweden)

    Budiman

    2015-02-01

    Full Text Available Black rice production in organic farming system does not meet the demand of local customers because of its low productivity. This research aimed to set an interaction model using multivariate analysis via smartPLS to identify environmental factors which simultaneously affects the growth of black rice. The growth of black rice in two irrigated organic paddy field in Malang, Indonesia was observed during planting period from November 2011 to March 2012. In each rice field, the growth was periodically recorded during planting periods: 19-29 days after planting (dap, 41-45 dap, 62-66 dap, 77-81 dap, 90-94 dap and 104-106 dap. Environmental factors such as water quantities, soil conditions, weed communities and cultivation system around the black rice population were also measured. Black rice growth was influenced simultaneously by water quantities, soil, weed communities and cultivating systems with predictive-relevance value reaching 92.83%. Based on the model, water quantities in paddy field is a key factor which directly and indirectly determined the growth and productivity of black rice.

  16. Glycaemic indices of different varieties of rice grown in Sri Lanka.

    Science.gov (United States)

    Hettiarachchi, P; Jiffry, M T; Jansz, E R; Wickramasinghe, A R; Fernando, D J

    2001-03-01

    Varieties of red raw rice are widely believed to have a better nutritional quality. The physiological effects of consuming different varieties of rice may not be so. The glycaemic index has been developed as an indicator of the physiological effect of foods. It is the glycaemic response of a 50 g carbohydrate portion of food expressed as a percentage of that of a standard. The objective of this study was to determine the glycaemic indices of different varieties of rice grown in Sri Lanka. Digestible carbohydrate content of 11 varieties of rice flour and bread were determined. Fasting blood samples followed by half-hourly samples for two hours were drawn after giving portions of either cooked rice or bread containing 50 g carbohydrate each. Fibre mill in Gampaha district. Twenty-two fibre mill workers aged between 25 and 50 years. The area under the blood glucose curve (AUC) for varieties of rice for a subject was calculated. Average AUC of 3 values for bread were calculated. Glycaemic index of each variety of rice was determined from the above variables. Glycaemic indices of varieties of rice differ. The glycaemic indices of varieties of red raw rice varied between 56 and 73 and the variety Bg 350 had the lowest glycaemic index. There was no significant difference between mean glycaemic index of varieties of white raw and some varieties of red raw rice (p = 0.2). Parboiled varieties of red raw rice had a significantly lower glycaemic index than white raw rice (p = 0.04) and some of the red raw rice (p = 0.005). The glycaemic index cannot be predicted from the colour of the rice grain. Red parboiled varieties of rice and Bg 350 can be recommended for patients with diabetes.

  17. BIOMETRIC PARAMETERS OF FIELD GROWN SESAME INFLUENCED BY ARBUSCULAR MYCORRHIZAL INOCULATION, ROCK PHOSPHATE FERTILIZATION AND IRRIGATION

    Directory of Open Access Journals (Sweden)

    V.S. Harikumar

    2017-08-01

    Full Text Available The aim of the study was to assess the effect of inoculation with arbuscular mycorrhizal fungi (AMF and rock phosphate (RP fertilization on biometric parameters and mycorrhizal colonization of field grown sesame under rainfed and irrigated conditions. Inoculation of AMF Funneliformis dimorphicus improved the biometric parameters of the crop such as leaf area (LA, leaf area index (LAI, specific leaf weight (SLW, net assimilation rate (NAR, oil index (OI as well as mycorrhizal colonization (%F in roots. Mycorrhizal inoculation however, did not give any positive response on harvest index (HI. LA, LAI and OI and %F showed a general increment in treatments of no added P (P0, while the other parameters such as SLW and NAR were improved by the application of RP at half the recommended dose (P50. HI did not respond to RP fertilization. Most of the parameters (LA, LAI, NAR, %F showed higher values under rainfed condition than irrigated condition whereas, SLW, HI and OI improved significantly under irrigated condition. Results indicated that the inoculation of AMF to field grown sesame can compensate for 50% of the recommended P fertilizer under a need based irrigation schedule, without affecting the biometric parameters.

  18. Genetic diversity studies on selected rice varieties grown in Africa ...

    African Journals Online (AJOL)

    Rice grain quality is an important factor that has a great influence on its market value and consumer acceptance. It is determined by three parameters controlling the cooking and eating qualities of rice (amylose content, gelatinization temperature and gel consistency) and by the aroma, which becomes a criterion ...

  19. Soil salinization processes in rice irrigation schemes in the Senegal River Delta

    International Nuclear Information System (INIS)

    Ceuppens, J.; Wopereis, M.C.S.; Miezan, K.M.

    1997-01-01

    Soil salinization constitutes a major threat to irrigated agriculture (mainly rice, Oryza sativa L.) in the Senegal River Delta. It is generally hypothesized that salinization is caused by (i) capillary rise from a saline water table and (ii) concentration of salts in the field due to lack of adequate drainage facilities. The impact of field water management and rice cropping intensity on salinization in the Delta was determined using an electromagnetic conductivity meter (Geonics EM38). More than 4000 measurements were made in 40 rice fields on a typical heavy clay soil (Vertic Xerofluvent). Thirty EM38 measurements per field (0.25 ha) estimated average field soil salinity with a relative error of 20%. A multiple linear regression model based on EM38 readings explained 60 to 75% of the variability in conductivity of 1:5 saturation extracts at 0- to 5-, 10- to 15-, and 30- to 35-cm depths. Higher cropping intensity limited upward salt transport from the water table. Average horizontal and vertical EM38 measurements increased in the following order two rice crops per year with drainage: 0.73 and 0.98 dS m -1 ; one rice crop per year with drainage: 1.26 and 1.76 dS m -1 ; one rice crop per year without drainage: 2.23 and 2.98 dS m -1 ; and abandoned fields: 4.77 and 4.29 dS m -1 . Results indicate a beneficial effect of flooded rice on salinity for this type of heavy clay soil. Irrigation development in the area needs to be accompanied by monitoring of water table depth. (author)

  20. Spectroscopic determination of essential elements in unpolished rice (oryza sativa l.), grown at rri, Dokri

    International Nuclear Information System (INIS)

    Shar, G.Q.; Arain, S.A.; Shar, L.A.; Kazi, T.G.; Sahito, S.

    2005-01-01

    seven rice varieties collected from, Rice Research institute (RRI) Dokri, Sindh in Pakistan. Agricultural soil samples was also collected to evaluate the bioavailability of eight essential elements to seven varieties of rice grown in the same agricultural plot. The agricultural soil and rice varieties were digested by wet acid digestion method. Homogeneity of the prepared materials was evaluated through the determination of eight essential elements i.e., Na, K, Mg, Ca, Fe, Mn, Zn, using flame atomic absorption spectrophotometer. The unpolished rice varieties contained high amount of essential micro nutrients such as Na, K, Mg, Ca, Fe, Mn, Zn, and Cu (616.01, 4097.15, 626.20, 73.90, 1829.88, 50.34, 42.72 and 7.21 mg/kg) in seven different varieties of rice i.e. DR-82, DR83, DR92, Kanwal-95, Lateefi, Sadahayat and Sarshar respectively. (author)

  1. Side-effects of pesticides used in irrigated rice areas on Telenomus podisi Ashmead (Hymenoptera: Platygastridae).

    Science.gov (United States)

    Pazini, Juliano de Bastos; Pasini, Rafael Antonio; Seidel, Enio Júnior; Rakes, Matheus; Martins, José Francisco da Silva; Grützmacher, Anderson Dionei

    2017-08-01

    Telenomus podisi Ashmead (Hymenoptera: Platygastridae) is an important agent for the biological control of stink bug eggs in irrigated rice areas and the best strategy for its preservation is the use of selective pesticides. The aim of this study was to know the side-effects of pesticides used in Brazilian irrigated rice areas on egg parasitoid T. podisi. We evaluated, under laboratory conditions, 13 insecticides, 11 fungicides, 11 herbicides, and a control (distilled water) in choice and no-choice tests. In the no-choice tests, the pesticides were sprayed at pre and post-parasitism stages (egg and larval stages of T. podisi). In the choice tests, sprays were conducted only at pre-parasitism stages. For all tests, we prepared cards with 25 eggs of the alternative host Euschistus heros (Fabricius) (Hemiptera: Pentatomidae) non-parasitized (pre-parasitism) and parasitized (post-parasitism), which were subjected to pesticide sprays. The parasitism and emergence rates of T. podisi were determined classifying the pesticides in terms of the reduction of parasitism or emergence rates compared to the control. The neurotoxic insecticide cypermethrin, lambda-cyhalothrin, zeta-cypermethrin, etofenprox, thiamethoxam, thiamethoxam + lambda-cyhalothrin, acetamiprid + alpha-cypermethrin, and bifenthrin + alpha-cypermethrin + carbosulfan were more harmful to T. podisi and, therefore, are less suitable for the integrated management of insect pests in irrigated rice areas.

  2. Phenolic compounds and vitamins in wild and cultivated apricot (Prunus armeniaca L.) fruits grown in irrigated and dry farming conditions.

    Science.gov (United States)

    Kan, Tuncay; Gundogdu, Muttalip; Ercisli, Sezai; Muradoglu, Ferhad; Celik, Ferit; Gecer, Mustafa Kenan; Kodad, Ossama; Zia-Ul-Haq, Muhammad

    2014-09-23

    Turkey is the main apricot producer in the world and apricots have been produced under both dry and irrigated conditions in the country. In this study, phenolic compounds and vitamins in fruits of one wild (Zerdali) and three main apricot cultivars ('Cataloglu', 'Hacihaliloglu' and 'Kabaasi') grown in both dry and irrigated conditions in Malatya provinces in Turkey were investigated. The findings indicated that higher content of phenolic compounds and vitamins was found in apricot fruits grown in irrigated conditions. Among the cultivars, 'Cataloglu' had the highest rutin contents both in irrigated and dry farming conditions as 2855 μg in irrigated and 6952 μg per 100 g dried weight base in dry conditions and the highest chlorogenic acid content in irrigated and dry farming conditions were measured in fruits of 'Hacıhaliloglu' cultivar as 7542 μg and 15251 μg per 100 g dried weight base. Vitamin C contents in homogenates of fruit flesh and skin was found to be higher than β-caroten, retinol, vitamin E and lycopen contents in apricot fruits both in irrigated and dry farming conditions. The results suggested that apricot fruits grown in both dry and irrigated conditions had high health benefits phytochemicals and phytochemical content varied among cultivars and irrigation conditions as well. However, more detailed biological and pharmacological studies are needed for the demonstration and clarification of health benefits of apricot fruits.

  3. Phenolic compounds and vitamins in wild and cultivated apricot (Prunus armeniaca L. fruits grown in irrigated and dry farming conditions

    Directory of Open Access Journals (Sweden)

    Tuncay Kan

    2014-01-01

    Full Text Available BACKGROUND: Turkey is the main apricot producer in the world and apricots have been produced under both dry and irrigated conditions in the country. In this study, phenolic compounds and vitamins in fruits of one wild (Zerdali and three main apricot cultivars ('Cataloglu', 'Hacihaliloglu' and 'Kabaasi' grown in both dry and irrigated conditions in Malatya provinces in Turkey were investigated. RESULTS: The findings indicated that higher content of phenolic compounds and vitamins was found in apricot fruits grown in irrigated conditions. Among the cultivars, 'Cataloglu' had the highest rutin contents both in irrigated and dry farming conditions as 2855 µg in irrigated and 6952 µg per 100 g dried weight base in dry conditions and the highest chlorogenic acid content in irrigated and dry farming conditions were measured in fruits of 'Hacıhaliloglu' cultivar as 7542 µg and 15251 µg per 100 g dried weight base. Vitamin C contents in homogenates of fruit flesh and skin was found to be higher than β-caroten, retinol, vitamin E and lycopen contents in apricot fruits both in irrigated and dry farming conditions. CONCLUSION: The results suggested that apricot fruits grown in both dry and irrigated conditions had high health benefits phytochemicals and phytochemical content varied among cultivars and irrigation conditions as well. However, more detailed biological and pharmacological studies are needed for the demonstration and clarification of health benefits of apricot fruits.

  4. Genetic diversity studies on selected rice varieties grown in Africa ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    similarity was observed between traditional aromatic rice Basmati 370 and the landrace Gambiaka. Nigeria. .... inheritance, abundance and extensive genome coverage ... market value, 4 landraces Gambiaka well spread in Africa, TS2 a.

  5. Arsenic transport in irrigation water across rice-field soils in Bangladesh

    International Nuclear Information System (INIS)

    Polizzotto, Matthew L.; Lineberger, Ethan M.; Matteson, Audrey R.; Neumann, Rebecca B.; Badruzzaman, A. Borhan M.; Ashraf Ali, M.

    2013-01-01

    Experiments were conducted to analyze processes impacting arsenic transport in irrigation water flowing over bare rice-field soils in Bangladesh. Dissolved concentrations of As, Fe, P, and Si varied over space and time, according to whether irrigation water was flowing or static. Initially, under flowing conditions, arsenic concentrations in irrigation water were below well-water levels and showed little spatial variability across fields. As flowing-water levels rose, arsenic concentrations were elevated at field inlets and decreased with distance across fields, but under subsequent static conditions, concentrations dropped and were less variable. Laboratory experiments revealed that over half of the initial well-water arsenic was removed from solution by oxidative interaction with other water-column components. Introduction of small quantities of soil further decreased arsenic concentrations in solution. At higher soil-solution ratios, however, soil contributed arsenic to solution via abiotic and biotic desorption. Collectively, these results suggest careful design is required for land-based arsenic-removal schemes. -- Highlights: •We analyzed the processes impacting arsenic transport in flowing irrigation water. •Arsenic in Bangladesh rice-field irrigation water varied over space and time. •Arsenic was correlated with Fe, P, and Si in flowing and static water. •Oxidation, adsorption and desorption reactions controlled arsenic concentrations. •Land-based arsenic removal from water will be impacted by hydraulic conditions. -- Arsenic concentrations in flowing and static irrigation water in Bangladesh varied over space and time, suggesting careful design is required for land-based pre-treatment schemes that aim to remove As from solution

  6. Effect of fertiliser on functional properties of flour from four rice varieties grown in Sri Lanka.

    Science.gov (United States)

    Gunaratne, Anil; Sirisena, Nihal; Ratnayaka, Upul Kumari; Ratnayaka, Jennet; Kong, Xiangli; Vidhana Arachchi, Lal Peruma; Corke, Harold

    2011-05-01

    Fertiliser is an essential agro-chemical input in modern rice farming. Fertiliser affects the grain quality and yield of rice. Although much research has been carried out to investigate the influence of fertiliser (recommended NPK addition) on yield and quality of rice grain, little is known about the effect of fertiliser on thermal, pasting, gelling and retrogradation properties of rice flour. The aim of this study was to investigate the influence of recommended fertilisation on functional properties of rice flour from four popular high yielding rice varieties grown in Sri Lanka. Fertiliser (recommended NPK addition) increased the protein content but reduced the apparent amylose content in rice flour except in BG 357. Swelling power and amylose leaching were decreased by fertilizer. [corrected] Pasting onset temperature, cold paste viscosity and setback were increased but peak viscosity and granular breakdown decreased. In response to the fertiliser application, gelatinisation peak temperature was reduced in all varieties except BG 300. However, compared to pasting properties, gelatinisation parameters were not much affected by fertilisation. The extent of amylopectin retrogradation was decreased by fertiliser in BG 305 and BG 352 but unchanged in the other two varieties. Except in BG 305, fertiliser reduced the gel hardness of rice flour but increased the gel cohesiveness. It is apparent that the increased protein and reduced amylose content caused by fertiliser affect the functional properties of rice flour. Copyright © 2011 Society of Chemical Industry.

  7. Yield-scaled global warming potential of two irrigation management systems in a highly productive rice system

    Directory of Open Access Journals (Sweden)

    Silvana Tarlera

    2016-02-01

    Full Text Available ABSTRACT Water management impacts both methane (CH4 and nitrous oxide (N2O emissions from rice paddy fields. Although controlled irrigation is one of the most important tools for reducing CH4emission in rice production systems it can also increase N2O emissions and reduce crop yields. Over three years, CH4 and N2O emissions were measured in a rice field in Uruguay under two different irrigation management systems, using static closed chambers: conventional water management (continuous flooding after 30 days of emergence, CF30; and an alternative system (controlled deficit irrigation allowing for wetting and drying, AWDI. AWDI showed mean cumulative CH4 emission values of 98.4 kg CH4 ha−1, 55 % lower compared to CF30, while no differences in nitrous oxide emissions were observed between treatments ( p > 0.05. No yield differences between irrigation systems were observed in two of the rice seasons ( p > 0.05 while AWDI promoted yield reduction in one of the seasons ( p< 0.05. When rice yield and greenhouse gases (GHG emissions were considered together, the AWDI irrigation system allowed for lower yield-scaled total global warming potential (GWP. Higher irrigation water productivity was achieved under AWDI in two of the three rice seasons. These findings suggest that AWDI could be an option for reducing GHG emissions and increasing irrigation water productivity. However, AWDI may compromise grain yield in certain years, reflecting the importance of the need for fine tuning of this irrigation strategy and an assessment of the overall tradeoff between relationships in order to promote its adoption by farmers.

  8. Expansion of urban area and wastewater irrigated rice area in Hyderabad, India

    Science.gov (United States)

    Gumma, K.M.; van, Rooijen D.; Nelson, A.; Thenkabail, P.S.; Aakuraju, Radha V.; Amerasinghe, P.

    2011-01-01

    The goal of this study was to investigate land use changes in urban and peri-urban Hyderabad and their influence on wastewater irrigated rice using Landsat ETM + data and spectral matching techniques. The main source of irrigation water is the Musi River, which collects a large volume of wastewater and stormwater while running through the city. From 1989 to 2002, the wastewater irrigated area along the Musi River increased from 5,213 to 8,939 ha with concurrent expansion of the city boundaries from 22,690 to 42,813 ha and also decreased barren lands and range lands from 86,899 to 66,616 ha. Opportunistic shifts in land use, especially related to wastewater irrigated agriculture, were seen as a response to the demand for fresh vegetables and easy access to markets, exploited mainly by migrant populations. While wastewater irrigated agriculture contributes to income security of marginal groups, it also supplements the food basket of many city dwellers. Landsat ETM + data and advanced methods such as spectral matching techniques are ideal for quantifying urban expansion and associated land use changes, and are useful for urban planners and decision makers alike. ?? 2011 Springer Science+Business Media B.V.

  9. Application of Azolla and intermittent irrigation to improve the productivity and nutrient contents of local black rice variety

    Science.gov (United States)

    Sulandjari; Yunindanova, M. B.

    2018-03-01

    Black rice is a local rice variety that contains a high level of anthocyanin pigment. Anthocyanin has been reported to be very effective in reducing cholesterol levels as well as cancer cell invasion. One of the main problems in rice cultivation is lack of water. System of Rice Intensification (SRI) has shown to be able to increase rice productivity by increasing the number of tillers. This system is known as a water-efficient cultivation. Other rice cultivation barrier is related to the use of nitrogen fertilizer. One of replacement of nitrogen fertilizer is by adding azolla. The objective of this research was identifying growth and yield of organic black rice with intermittent irrigation and application of azolla. The plant material used was black rice Cempo variety from Sleman, Yogyakarta. This experiment utilized 4 dosages of azolla as the first treatment: 100 gm-2, 200 gm-2 and 400 gm-2. The second treatment was water supply consisted of continuous flooded 2 cm; flooded 2 cm every 3 days; flooded 2 cm every 6 days. The results depicted that the application of azolla was able to increase the growth of black rice. Azolla of 200 gm-2 and 400 gm-2 and intermittent 3 days to 6 days generated higher dry grain, anthocyanin and antioxidant. Azolla 200 gm-2 with intermittent irrigation 3 days could be a good combination to improve plant growth, yield and properties of local black rice.

  10. Testing climate-smart irrigation strategies to reduce methane emissions from rice fields

    Science.gov (United States)

    Runkle, B.; Suvocarev, K.; Reba, M. L.

    2017-12-01

    Approximately 11% of the global 308 Tg CH4 anthropogenic emissions are currently attributed to rice cultivation. In this study, the impact of water conservation practices on rice field CH4 emissions was evaluated in Arkansas, the leading state in US rice cultivation. While conserving water, the Alternate Wetting and Drying (AWD) irrigation practice can also reduce CH4 emissions through the deliberate, periodic introduction of aerobic conditions. Seasonal CH4emissions from a pair of adjacent, production-sized rice fields were estimated and compared during the 2015 to 2017 growing seasons using the eddy covariance method on each field. The fields were alternately treated with continuous flood (CF) and AWD irrigation. In 2015, the seasonal cumulative carbon losses by CH4 emission were 30.3 ± 6.3 and 141.9 ± 8.6 kg CH4-C ha-1 for the AWD and CF treatments, respectively. Data from 2016 and 2017 will be analyzed and shown within this presentation; an initial view demonstrates consistent findings to 2015. When accounting for differences in field conditions and soils, the AWD practice is attributable to a 36-51% reduction in seasonal emissions. The substantial decrease in CH4 emissions by AWD supports previous chamber-based research and offers strong evidence for the efficacy of AWD in reducing CH4 emissions in Arkansas rice production. The AWD practice has enabled the sale of credits for carbon offsets trading and this new market could encourage CH4 emissions reductions on a national scale. These eddy covariance towers are being placed into a regional perspective including crop and forest land in the three states comprising the Mississippi Delta: Arkansas, Mississippi, and Louisiana.

  11. Rice evapotranspiration at the field and canopy scales under water-saving irrigation

    Science.gov (United States)

    Liu, Xiaoyin; Xu, Junzeng; Yang, Shihong; Zhang, Jiangang

    2018-04-01

    Evapotranspiration (ET) is an important process of land surface water and thermal cycling, with large temporal and spatial variability. To reveal the effect of water-saving irrigation (WSI) on rice ET at different spatial scales and understand the cross spatial scale difference, rice ET under WSI condition at canopy (ETCML) and field scale (ETEC) were measured simultaneously by mini-lysimeter and eddy covariance (EC) in the rice season of 2014. To overcome the shortage of energy balance deficit by EC system, and evaluate the influence of energy balance closure degree on ETEC, ETEC was corrected as {ET}_{EC}^{*} by energy balance closure correction according to the evaporative fraction. Seasonal average daily ETEC, {ET}_{EC}^{*} and ETCML of rice under WSI practice were estimated as 3.12, 4.03 and 4.35 mm day-1, smaller than the values reported in flooded paddy fields. Daily ETEC, {ET}_{EC}^{*} and ETCML varied in a similar trends and reached the maximum in late tillering, then decreased along with the crop growth in late season. The value of ETEC was much lower than ETCML, and was frequently 1-2 h lagged behind ETCML. It indicated that the energy balance deficit resulted in underestimation of crop ET by EC system. The corrected value of {ET}_{EC}^{*} matched ETCML much better than ETEC, with a smaller RMSE (0.086 mm h-1) and higher R 2 (0.843) and IOA (0.961). The time lapse between {ET}_{EC}^{*} and ETCML was mostly shortened to less than 0.5 h. The multiple stepwise regression analysis indicated that net radiation ( R n) is the dominant factor for rice ET, and soil moisture ( θ) is another significant factor ( p rice fields. The difference between ETCML and {ET}_{EC}^{*} ({ET}_{CML} - {ET}_{EC}^{*}) were significantly ( p rice ET in WSI fields, and for its cross scale conversion.

  12. Microbial, physical and chemical properties of irrigation water in rice fields of Southern Brazil

    Directory of Open Access Journals (Sweden)

    MARIA HELENA L.R. RECHE

    2016-03-01

    Full Text Available ABSTRACT This paper presents the results of the statistical analysis of microbiological, physical and chemical parameters related to the quality of the water used in rice fields in Southern Brazil. Data were collected during three consecutive crop years, within structure of a comprehensive monitoring program. The indicators used were: potential hydrogen, electrical conductivity, turbidity, nitrogen, phosphorus, potassium, calcium, total and fecal coliforms. Principal Component and Discriminant Analysis showed consistent differences between the water irrigation and drainage, as the temporal variation demonstrated a clear reduction in the concentration of most of the variables analyzed. The pattern of this reduction is not the same in the two regions - that is, the importance of each of the different variables in the observed differentiation is modified in two locations. These results suggested that the variations in the water quality utilized for rice irrigation was influenced by certain specific aspects of each rice region in South Brazilian - such as anthropic action or soil/climate conditions in each hydrographic basin.

  13. Speciation of methylmercury in rice grown from a mercury mining area

    Energy Technology Data Exchange (ETDEWEB)

    Li Lu [Department of Environment and Geography, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada); Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada); State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing100085 (China); Wang Feiyue, E-mail: wangf@ms.umanitoba.c [Department of Environment and Geography, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada); Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada); Meng Bo [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang, Guizhou 550002 (China); Lemes, Marcos [Department of Environment and Geography, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada); Department of Chemistry, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada); Feng Xinbin [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang, Guizhou 550002 (China); Jiang Guibin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing100085 (China)

    2010-10-15

    Monomethylmercury (CH{sub 3}Hg{sup +} and its complexes; MeHg hereafter) is a known developmental neurotoxin. Recent studies have shown that rice (Oryza sativa L.) grain grown from mercury (Hg) mining areas may contain elevated MeHg concentrations, raising concerns over the health of local residents who consume rice on a daily basis. An analytical method employing high performance liquid chromatography (HPLC) - inductively coupled plasma mass spectrometry (ICP-MS) following enzymatic hydrolysis was developed to analyze the speciation of MeHg in uncooked and cooked white rice grain grown from the vicinity of a Hg mine in China. The results revealed that the MeHg in the uncooked rice is present almost exclusively as CH{sub 3}Hg-L-cysteinate (CH{sub 3}HgCys), a complex that is thought to be responsible for the transfer of MeHg across the blood-brain and placental barriers. Although cooking does not change the total Hg or total MeHg concentration in rice, no CH{sub 3}HgCys is measurable after cooking, suggesting that most, if not all, of the CH{sub 3}HgCys is converted to other forms of MeHg, the identity and toxicity of which remain elusive. - Methylmercury in uncooked rice occurs predominantly as methylmercury-L-cysteinate, which is effectively removed during the cooking process.

  14. Rice yellow mottle virus is transmitted by cows, donkeys, and grass rats in irrigated rice crops

    NARCIS (Netherlands)

    Sarra, S.; Peters, D.

    2003-01-01

    Rice yellow mottle virus (RYMV), endemic in Africa, is believed to be spread by chrysomelid beetles, although the infections in a field often cannot be explained by the prevailing number of beetles. We show that the grass rat Arvicanthis niloticus, domestic cows (Bos spp.), and donkeys (Asinus spp.)

  15. Microbial community analysis in rice paddy soils irrigated by acid mine drainage contaminated water.

    Science.gov (United States)

    Sun, Min; Xiao, Tangfu; Ning, Zengping; Xiao, Enzong; Sun, Weimin

    2015-03-01

    Five rice paddy soils located in southwest China were selected for geochemical and microbial community analysis. These rice fields were irrigated with river water which was contaminated by Fe-S-rich acid mine drainage. Microbial communities were characterized by high-throughput sequencing, which showed 39 different phyla/groups in these samples. Among these phyla/groups, Proteobacteria was the most abundant phylum in all samples. Chloroflexi, Acidobacteria, Nitrospirae, and Bacteroidetes exhibited higher relative abundances than other phyla. A number of rare and candidate phyla were also detected. Moreover, canonical correspondence analysis suggested that pH, sulfate, and nitrate were significant factors that shaped the microbial community structure. In addition, a wide diversity of Fe- and S-related bacteria, such as GOUTA19, Shewanella, Geobacter, Desulfobacca, Thiobacillus, Desulfobacterium, and Anaeromyxobacter, might be responsible for biogeochemical Fe and S cycles in the tested rice paddy soils. Among the dominant genera, GOUTA19 and Shewanella were seldom detected in rice paddy soils.

  16. EFFECTS OF IRRIGATION FREQUENCY AND LEAF DETACHMENT ON CHRYSANTHEMUM GROWN IN TWO TYPES OF PLASTIC HOUSE

    Directory of Open Access Journals (Sweden)

    K. Budiarto

    2016-10-01

    Full Text Available Chrysanthemum is one of important ornamentals in Indonesia and it ranks in the first quantity of cut flower marketed every year. In most cases, the low productivity is still a constraint for the traditional growers to make production process profitable. Several problems revealed in chrysanthemum production were investigated. The study dealt with the effect of two types of plastic house constructions, irrigation frequency, and leaf detachment on the growth and development of chrysanthemum. The experiment was conducted at Segunung, Indonesian Ornamental Plants Research Institute during the dry season of 2005. A nested design with six replications was used. The results showed that plants grown in wood-constructed plastic house had better growth performance and flower quality than those under bamboo plastic house. Longer stem and higher plant fresh weight with more flowers and longer life span were also observed on chrysanthemum irrigated four times per week than those irrigated twice per week. Leaf removal often practiced by the growers is no longer recommended, since the number of leaves on the plant influenced all parameters observed. The more leaves were detached, the more negative impacts on plant growth were found.

  17. Mapping Changes in Area and the Cropping Season of Irrigated Rice in Senegal and Mauritania between 2003 and 2014 Using the PhenoRice Algorithm and MODIS Imagery

    Science.gov (United States)

    Zwart, S.; Busetto, L.; Diagne, M.; Boschetti, M.; Nelson, A.

    2017-12-01

    Government policies have resulted in rapid expansion of irrigated rice area in Mauritania and Senegal through private and public investments. Farmers switch rice cultivation from the wet to the dry season to achieve higher production while rice double cropping is increasingly practiced. As a result Senegal is close to attaining self-sufficiency in the coming years. However, tools to monitor those changes are absent and this inhibits assessments on for example its impact on wetlands located in the delta area, increased water demands and climate induced risks to farmers. In this study we aimed to map changes in irrigated rice area in the wet and dry seasons. We applied the PhenoRice algorithm on a combined time-series of MODIS Aqua and Terra images obtained between 2003 and 2016 to map pixels dominated by rice and determine the start, end and length of the growing season from sowing/transplanting to maturity. Between 2002 and 2010 researchers from the Africa Rice Center interviewed annually around 100 rice farmers located in two irrigation schemes in Senegal. We extracted the reported sowing/transplanting and harvest dates from the data base and used these to validate the estimates obtained by PhenoRice. We also compared the obtained rice areas with official statistics provided by the Senegalese Ministry of Agriculture. Analysis of PhenoRice results highlighted that starting 2008, rice farmers cultivate also during the dry season; the area is steadily increasing from 2008 onwards and in the recent years approximately almost equals that of the wet season. This was confirmed by official statistics, though the total area estimated by PhenoRice is smaller than reported, most likely due to the mismatch between pixel size and the small cultivated areas. However, the algorithm was able to detect the overall trends and inter-annual variations observed in the wet (r2=0.57) and dry season rice cultivated area (r2=0.91). The start of the season, that varied maximally 4 weeks

  18. Economic Benefits of Aerobic Rice Grown Using Integrated Nitrogen Management

    Directory of Open Access Journals (Sweden)

    Nyle A. Pardillo

    2017-11-01

    Full Text Available This study focuses in the effect of integrated nitrogen management to the yield and economic benefits of aerobic rice. This will help farmers to identify which of the two management technique to use to save costs while profit is high. A split plot experiment in Randomized Complete Block design is used with two main treatments and four sub treatments. Main treatments are the use of integrated nitrogen management and an application of synthetic nitrogen fertilizer. Sub treatments are the different rates of nitrogen fertilizer from 0 as control, 90, 120 and 150 kg N ha-1 . Data are consolidated and analyzed using the ANOVA of SAS 9.3 statistical tool and comparison means at 5% significance level in Duncan Multiple Range Test. Grain yield, income, costs, profit and return on expenses are the data gathered. There is an increasing yield from control to 120 kg N ha-1 and started to decline at 150 kg N ha-1 because optimum level reached at 120 kg N ha-1 . Significant increased in yield was observed in plants applied with integrated nitrogen management at 120 kg N ha-1 compared to plants applied with synthetic nitrogen due to release of nitrogen that contributed to the yield of aerobic rice. However, plants applied of 90 kg N ha-1 synthetic nitrogen gives significant yield increased compared to plants with integrated nitrogen management. Yield was subjected to economic analysis using gross income, costs and profit and return on expenses. Plants applied with synthetic nitrogen at 90 kg N ha-1 resulted to high income due to lower costs of fertilizer inputs and only treatment that has a positive return on expenses at 3.2% while other treatments have a negative remarks. This will lead to a conclusion that 90 kg N ha-1 is the optimum level of nitrogen that can give high yield and positive return on expenses that farmers will benefited.

  19. Doses and application methods of Azospirillum brasilense in irrigated upland rice

    Directory of Open Access Journals (Sweden)

    Nayara F. S. Garcia

    Full Text Available ABSTRACT The study was carried out in Selvíria-MS, in the 2011/12 and 2012/13 agricultural years, aiming to evaluate the efficiency of Azospirillum brasilense in nitrogen fixation in upland rice, as a function of doses and application methods of the inoculant containing this diazotrophic bacterium. The experimental design was randomized blocks, arranged in a 4 x 4 factorial scheme, with 4 doses of inoculant (control without inoculation, 100, 200 and 300 mL of the commercial product ha-1 and 4 application methods (seed inoculation, application in the sowing furrow, soil spraying after sowing, and foliar spraying at the beginning of plant tillering, with 4 replicates. During the experiment, the agronomic characteristics, production components and yield of the rice crop were evaluated. It was concluded that the inoculant containing Azospirillum brasilense promotes increase (19% in the yield of upland rice under sprinkler irrigation when used at the dose of 200 mL ha-1, regardless of the application methods.

  20. EFFECT OF ALTERNATING WETTING AND DRYING IRRIGATION METHODS ON PHOTOSYNTHESIS AND TEMPERATURE OF RICE AND WEED PLANTS.

    Science.gov (United States)

    Reduced input systems such as alternating wetting and drying (AWD) and furrow irrigation can potentially reduce water costs and limit the release of greenhouse gases in rice production, but also can introduce unwanted crop stresses that compromise crop yield and quality, as well as introducing compl...

  1. Effects of irrigation strategies and soils on field-grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Andersen, Mathias Neumann; Plauborg, Finn

    2010-01-01

    Gas exchange was measured in potatoes (cv. Folva) grown in lysimeters (4.32 m2) in coarse sand, loamy sand, and sandy loam and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. PRD and DI as water-saving irrigation treatments received 65% of FI...... measurements showed that An reached peak values during mid-morning and midday, while gs were highest during the morning. Intrinsic water use efficiency (An/gs) correlated linearly well with the leaf to air vapor pressure deficit (VPD) and the slope of the line revealed the rate of An/gs increase per each k......Pa increase in VPD, i.e. approximately 10 μmol mol-1. Transpiration efficiency (An/T) of PRD was higher than DI, which shows slightly better efficient water use than DI. The slope of the linear relationship between transpiration efficiency and VPD decreased from -2.03 to -1.04 during the time course...

  2. Increasing water productivity, nitrogen economy, and grain yield of rice by water saving irrigation and fertilizer-N management.

    Science.gov (United States)

    Aziz, Omar; Hussain, Saddam; Rizwan, Muhammad; Riaz, Muhammad; Bashir, Saqib; Lin, Lirong; Mehmood, Sajid; Imran, Muhammad; Yaseen, Rizwan; Lu, Guoan

    2018-06-01

    The looming water resources worldwide necessitate the development of water-saving technologies in rice production. An open greenhouse experiment was conducted on rice during the summer season of 2016 at Huazhong Agricultural University, Wuhan, China, in order to study the influence of irrigation methods and nitrogen (N) inputs on water productivity, N economy, and grain yield of rice. Two irrigation methods, viz. conventional irrigation (CI) and "thin-shallow-moist-dry" irrigation (TSMDI), and three levels of nitrogen, viz. 0 kg N ha -1 (N 0 ), 90 kg N ha -1 (N 1 ), and 180 kg N ha -1 (N 2 ), were examined with three replications. Study data indicated that no significant water by nitrogen interaction on grain yield, biomass, water productivity, N uptake, NUE, and fertilizer N balance was observed. Results revealed that TSMDI method showed significantly higher water productivity and irrigation water applications were reduced by 17.49% in TSMDI compared to CI. Thus, TSMDI enhanced root growth and offered significantly greater water saving along with getting more grain yield compared to CI. Nitrogen tracer ( 15 N) technique accurately assessed the absorption and distribution of added N in the soil crop environment and divulge higher nitrogen use efficiency (NUE) influenced by TSMDI. At the same N inputs, the TSMDI was the optimal method to minimize nitrogen leaching loss by decreasing water leakage about 18.63%, which are beneficial for the ecological environment.

  3. Effects of water-saving irrigation on emissions of greenhouse gases and prokaryotic communities in rice paddy soil.

    Science.gov (United States)

    Ahn, Jae-Hyung; Choi, Min-Young; Kim, Byung-Yong; Lee, Jong-Sik; Song, Jaekyeong; Kim, Gun-Yeob; Weon, Hang-Yeon

    2014-08-01

    The effects of water-saving irrigation on emissions of greenhouse gases and soil prokaryotic communities were investigated in an experimental rice field. The water layer was kept at 1-2 cm in the water-saving (WS) irrigation treatment and at 6 cm in the continuous flooding (CF) irrigation treatment. WS irrigation decreased CH(4) emissions by 78 % and increased N(2)O emissions by 533 %, resulting in 78 % reduction of global warming potential compared to the CF irrigation. WS irrigation did not affect the abundance or phylogenetic distribution of bacterial/archaeal 16S rRNA genes and the abundance of bacterial/archaeal 16S rRNAs. The transcript abundance of CH(4) emission-related genes generally followed CH(4) emission patterns, but the difference in abundance between mcrA transcripts and amoA/pmoA transcripts best described the differences in CH(4) emissions between the two irrigation practices. WS irrigation increased the relative abundance of 16S rRNAs and functional gene transcripts associated with Anaeromyxobacter and Methylocystis spp., suggesting that their activities might be important in emissions of the greenhouse gases. The N(2)O emission patterns were not reflected in the abundance of N(2)O emission-related genes and transcripts. We showed that the alternative irrigation practice was effective for mitigating greenhouse gas emissions from rice fields and that it did not affect the overall size and structure of the soil prokaryotic community but did affect the activity of some groups.

  4. Towards Global Simulation of Irrigation in a Land Surface Model: Multiple Cropping and Rice Paddy in Southeast Asia

    Science.gov (United States)

    Beaudoing, Hiroko Kato; Rodell, Matthew; Ozdogan, Mutlu

    2010-01-01

    Agricultural land use significantly influences the surface water and energy balances. Effects of irrigation on land surface states and fluxes include repartitioning of latent and sensible heat fluxes, an increase in net radiation, and an increase in soil moisture and runoff. We are working on representing irrigation practices in continental- to global-scale land surface simulation in NASA's Global Land Data Assimilation System (GLDAS). Because agricultural practices across the nations are diverse, and complex, we are attempting to capture the first-order reality of the regional practices before achieving a global implementation. This study focuses on two issues in Southeast Asia: multiple cropping and rice paddy irrigation systems. We first characterize agricultural practices in the region (i.e., crop types, growing seasons, and irrigation) using the Global data set of monthly irrigated and rainfed crop areas around the year 2000 (MIRCA2000) dataset. Rice paddy extent is identified using remote sensing products. Whether irrigated or rainfed, flooded fields need to be represented and treated explicitly. By incorporating these properties and processes into a physically based land surface model, we are able to quantify the impacts on the simulated states and fluxes.

  5. Evaluation of Protocols for Measuring Leaf Photosynthetic Properties of Field-Grown Rice

    Directory of Open Access Journals (Sweden)

    Chang Tian-gen

    2017-01-01

    Full Text Available Largely due to the heterogeneity of environmental parameters and the logistical difficulty of moving photosynthetic equipment in the paddy fields, effective measurement of lowland rice photosynthesis is still a challenge. In this study, we showed that measuring detached rice leaves in the laboratory can not effectively represent the parameters measured in situ. We further described a new indoor facility, high-efficiency all-weather photosynthetic measurement system (HAPS, and the associated measurement protocol to enable whole-weather measurement of photosynthetic parameters of rice grown in the paddy fields. Using HAPS, we can conduct photosynthetic measurements with a time span much longer than that appropriate for the outdoor measurements. Comparative study shows that photosynthetic parameters obtained with the new protocol can effectively represent the parameters in the fields. There was much less standard deviation for measurements using HAPS compared to the outdoor measurements, no matter for technical replications of each recording or for biological replications of each leaf position. This new facility and protocol enables rice photosynthetic physiology studies to be less tough but more efficient, and provides a potential option for large scale studies of rice leaf photosynthesis.

  6. Performance of super hybrid rice cultivars grown under no-tillage and direct seeding

    Directory of Open Access Journals (Sweden)

    Min Huang

    2012-04-01

    Full Text Available Good progress has been made in the super hybrid rice (Oryza sativa L. breeding in China. However, rice yield not only depends on the genetic characteristics but also on the agronomic practices. No-tillage and direct seeding (NTDS is a simplified cultivation technology that greatly simplifies both land preparation and crop establishment. Aiming to determine the grain yield performance of super hybrid rice under NTDS and to identify critical factors that determine grain yield, field experiments were conducted in Nanxian, Hunan Province, China in 2009 and 2010. Two super hybrid cultivars, Liangyoupeijiu and Y-liangyou 1, were grown under conventional tillage and transplanting (CTTP and NTDS. Grain yield, yield components, biomass production, crop growth rate and biomass accumulation during sowing to heading (HD and HD to maturity were measured for each cultivar. There was no difference in grain yield under NTDS and CTTP. However, grain yield differed with cultivar and year. Y-liangyou 1 produced 4 % higher grain yield than Liangyoupeijiu in 2009, whereas in 2010 both cultivars yielded similarly. Grain yields of both cultivars were higher in 2009 than in 2010. Higher grain yield of Y-liangyou 1 in 2009 was associated with higher spikelet filling (spikelet filling percentage and grain weight, which resulted from higher biomass production. Crop growth rate after HD was critical for biomass production by the super hybrid rice. We suggest that increasing the crop growth rate after HD is an effective approach to increase grain yield of super hybrid rice under NTDS.

  7. Effects of Residue Management on Decomposition in Irrigated Rice Fields Are Not Related to Changes in the Decomposer Community.

    Directory of Open Access Journals (Sweden)

    Anja Schmidt

    Full Text Available Decomposers provide an essential ecosystem service that contributes to sustainable production in rice ecosystems by driving the release of nutrients from organic crop residues. During a single rice crop cycle we examined the effects of four different crop residue management practices (rice straw or ash of burned straw scattered on the soil surface or incorporated into the soil on rice straw decomposition and on the abundance of aquatic and soil-dwelling invertebrates. Mass loss of rice straw in litterbags of two different mesh sizes that either prevented or allowed access of meso- and macro-invertebrates was used as a proxy for decomposition rates. Invertebrates significantly increased total loss of litter mass by up to 30%. Initially, the contribution of invertebrates to decomposition was significantly smaller in plots with rice straw scattered on the soil surface; however, this effect disappeared later in the season. We found no significant responses in microbial decomposition rates to management practices. The abundance of aquatic fauna was higher in fields with rice straw amendment, whereas the abundance of soil fauna fluctuated considerably. There was a clear separation between the overall invertebrate community structure in response to the ash and straw treatments. However, we found no correlation between litter mass loss and abundances of various lineages of invertebrates. Our results indicate that invertebrates can contribute to soil fertility in irrigated paddy fields by decomposing rice straw, and that their abundance as well as efficiency in decomposition may be promoted by crop residue management practices.

  8. Effects of Residue Management on Decomposition in Irrigated Rice Fields Are Not Related to Changes in the Decomposer Community.

    Science.gov (United States)

    Schmidt, Anja; John, Katharina; Arida, Gertrudo; Auge, Harald; Brandl, Roland; Horgan, Finbarr G; Hotes, Stefan; Marquez, Leonardo; Radermacher, Nico; Settele, Josef; Wolters, Volkmar; Schädler, Martin

    2015-01-01

    Decomposers provide an essential ecosystem service that contributes to sustainable production in rice ecosystems by driving the release of nutrients from organic crop residues. During a single rice crop cycle we examined the effects of four different crop residue management practices (rice straw or ash of burned straw scattered on the soil surface or incorporated into the soil) on rice straw decomposition and on the abundance of aquatic and soil-dwelling invertebrates. Mass loss of rice straw in litterbags of two different mesh sizes that either prevented or allowed access of meso- and macro-invertebrates was used as a proxy for decomposition rates. Invertebrates significantly increased total loss of litter mass by up to 30%. Initially, the contribution of invertebrates to decomposition was significantly smaller in plots with rice straw scattered on the soil surface; however, this effect disappeared later in the season. We found no significant responses in microbial decomposition rates to management practices. The abundance of aquatic fauna was higher in fields with rice straw amendment, whereas the abundance of soil fauna fluctuated considerably. There was a clear separation between the overall invertebrate community structure in response to the ash and straw treatments. However, we found no correlation between litter mass loss and abundances of various lineages of invertebrates. Our results indicate that invertebrates can contribute to soil fertility in irrigated paddy fields by decomposing rice straw, and that their abundance as well as efficiency in decomposition may be promoted by crop residue management practices.

  9. Diet and resource partitioning among anurans in irrigated rice fields in Pantanal, Brazil

    Directory of Open Access Journals (Sweden)

    L. Piatti

    Full Text Available Artificial ponds or irrigated systems scattered throughout farmlands can offer important habitats for anurans and can be interesting sites for research on species resources use in a changing landscape. This study describes the diet and resource partitioning among anurans inhabiting irrigated rice fields in the Pantanal region. Twenty categories of prey were found in the stomachs of Leptodactylus chaquensis, L. elenae, L. podicipinus and Rhinella bergi, the most frequent being Coleoptera, Hymenoptera, larvae of Hexapoda, Hemiptera, Diptera and Orthoptera. The great differences found in the diet of these species in rice fields compared to other locations, according to available records in the literature, was the increased importance of Hemipitera and Orthoptera and the decrease in importance of Hymenoptera in the diet of leptodactylids. These differences might be attributed to changes in the availability of resources in response to habitat modification. Although diet composition was very similar among species, niche overlap was larger than expected by chance, suggesting that the competition for food resources is not, or has not been, a significant force in determining the structure of this frog community. Two non-exclusive hypotheses could be considered as a justification for this result: 1 the high niche overlap could result from resource availability, which is sufficient to satisfy all species without any strong competition; 2 or the high values of niche overlap could be a selective force driving species to compete, but there has not been enough time to express a significant divergence in the species diet because the study area is characterised as a dynamic habitat influenced by frequent and cyclical changes.

  10. Water Productivity of Irrigated Rice under Transplanting, Wet Seeding and Dry Seeding Methods of Cultivation

    Directory of Open Access Journals (Sweden)

    Murali, NS.

    1997-01-01

    Full Text Available Water productivity (WP of irrigated lowland rice was determined during the 1994 dry (January to May and wet (August to December seasons on a heavy clay acid sulphate soil. Treatments consisted of three cultivation methods : transplanted rice, pregerminated seeds broadcasted on puddled soil (wet seeding and dry seeds broadcasted on unpuddled soil (dry seeding. In wet and dry seeded plots, continuous standing water condition was initiated 17 days after sowing. Total water requirement for rice production was highest in transplanted plots (755 mm in wet season and 1154 mm in dry season and was lowest in dry seeded plots (505 mm in wet season and 1040 mm in dry season. Dry seeding required no water for land preparation but transplanting and wet seeding methods required 18 - 20 % of total water requirement in dry season and 27 - 29 % in wet season. Total percolation was maximum (99 mm in wet season and 215 mm in dry season in dry seeding method and was minimum (62 mm in wet season and 94 mm in dry season in transplanting method. In dry and wet seeding methods, daily percolation gradually decreased with the age of the crop. Total seepage loss did not show any significant difference between the cultivation methods in the two seasons. Grain yield was not affected by the three cultivation methods in both seasons. Water productivity (the ratio between grain yield and total amount of water used in production was 3.5 - 4.1 kg ha-1 mm-1, 3.8 - 4.4 kg ha-1 mm-1 and 4.1 - 5.5 kg ha-1 mm-1 in transplanted, wet seeded and dry seeded rice, respectively. Labour requirement for land preparation and sowing was maximum in transplanted (219 - 226 man-hours ha-1 followed by wet (104 -112 man-hours ha-1 and dry seeded (94 - 99 man-hours ha-1 methods. However, in wet season extra labour (77 man-hours ha-1 was required for weeding after crop establishment in dry and wet seeding methods. Crop maturity was 20 days earlier in wet and dry seeding methods compared to

  11. Influence of gypsum amendment on methane emission from paddy rice soil affected by saline irrigation water

    Directory of Open Access Journals (Sweden)

    Ei Ei eTheint

    2016-01-01

    Full Text Available To investigate the influence of gypsum application on methane (CH4 emission from paddy rice soil affected by saline irrigation water, two pot experiments with the rice cultivation were conducted. In pot experiment (I, salinity levels 30 mMNaCl (S30 and 90 mMNaCl (S90, that showed maximum and minimum CH4 production in an incubation experiment, respectively, were selected and studied without and with application of 1 Mg gypsum ha-1(G1. In pot experiment (II, CH4 emission was investigated under different rates of gypsum application: 1 (G1, 2.5 (G2.5 and 5 (G5 Mg gypsum ha-1 under a non-saline and saline condition of 25 mMNaCl (S25. In experiment (I, the smallest CH4 emission was observed in S90. Methane emission in S30 was not significantly different with the non-saline control. The addition of gypsum showed significant lower CH4 emission in saline and non-saline treatments compared with non-saline control. In experiment (II, the CH4 emissions in the saline treatments were not significantly different to the non-saline treatments except S25-G5. However, our work has shown that gypsum can lower CH4 emissions under saline and non-saline conditions. Thus, gypsum can be used as a CH4 mitigation option in non-saline as well as in saline conditions.

  12. Production of Mozzarella Cheese Using Rennin Enzyme from Mucor miehei Grown at Rice Bran Molasses Medium

    Science.gov (United States)

    Rusdan, I. H.; Kusnadi, J.

    2017-04-01

    The research aimed to study the characteristic and yield of Mozzarella cheese produced by using rennin enzyme from Mucor miehei which is grown at rice bran and molasses medium. The popularity of Mozzarella cheese in Indonesia is increased caused by the spreading of western foods in Indonesia such as pizza and spaghetti that use Mozzarella cheese for ingredient. In Italy, Mozzarella and pizza cheeses are dominating 78% of the total Italian Cheese products. In producing Mozzarella cheese, rennin enzyme is always used as milk coagulant. Even now, Indonesia has not produced the rennin enzyme yet. The rennin enzyme from Mucor miehei growing at rice bran and molases medium which have the availability can be managed purposively within short period of time. The completly randomized design methode used to get the best crude extracts of Mucor miehei rennin enzyme, then is employed to produce mozzarella cheese. The result of Mozzarella cheese has various characteristics such as the yield’s weight is 9.1%, which consists of 50% moisture content, 36.64% peotein levels, 0.1 melting ability and 82.72% stretch ability or 0.79/N. With that characteristic it is concluded that rennin enzyme from Mucor miehei grown at rice bran molasses medium has the potential to alternatively subtitute calf rennin to produce Mozzarella cheese, and the characteristics fulfill the standart.

  13. Water reuse and cost-benefit of pumping at different spatial levels in a rice irrigation system in UPRIIS, Philippines

    Science.gov (United States)

    Hafeez, M. M.; Bouman, B. A. M.; Van de Giesen, N.; Mushtaq, S.; Vlek, P.; Khan, S.

    As agricultural water resources in Asia become increasingly scarce, the irrigation efficiency of rice must be improved. However, in this region there is very limited information available about water use efficiency across spatial levels in irrigation systems. This study quantifies the volume of water reuse and its related cost-benefits at five different spatial levels, ranging from 1500 ha to 18,000 ha, under gravity-fed irrigation system in Upper Pumpanga River Integrated Irrigation System (UPRIIS), Philippines. The major sources of water reuse are considered, namely groundwater pumping, pumping from creeks, combined use and irrigation supplies from check dams. The volume of water available from all four sources of water reuse was quantified through extensive measurements. Production functions were developed to quantify water-yield relationships and to measure the economic value of water reuse. This study was conducted during the dry season of 2001, which existed from 19 November 2000 until 18 May 2001. The water reuse by pumping and check dams was 7% and 22% of the applied surface water at District 1 level. The reuse of surface water through check dams increased linearly with 4.6 Mm 3 per added 1000 ha. Similarly, the total amount of reused water from pumping is equivalent to 30% of the water lost through rice evapotranspiration during the dry season 2001. The results showed that water reuse plays a dominant role in growing a rice crop during the dry season. The result showed no difference in pumping costs between the creek (US0.011/m 3) and shallow pumps (US0.012/m 3). The marginal value of productivity (MVP) of water reuse from creek (US0.044/m 3) was slightly higher than the water reuse through the pumping ground water (US0.039/m 3). Results also indicated that the total volume pumped per ha (m 3/ha) was ranging from 0.39 to 6.93 m 3/ha during the dry season. The results clearly indicate that the quantification of amount of water reuse is very crucial for

  14. Irrigation with oxygen-nanobubble water can reduce methane emission and arsenic dissolution in a flooded rice paddy

    Science.gov (United States)

    Minamikawa, Kazunori; Takahashi, Masayoshi; Makino, Tomoyuki; Tago, Kanako; Hayatsu, Masahito

    2015-08-01

    A remarkable feature of nanobubbles (pot experiment and measuring redox-related variables. The NBs were introduced into control water (with properties similar to those of river water) using a commercially available generator. Rice (Oryza sativa L.) growth did not differ between plants irrigated with NB water and those irrigated with control water, but NB water significantly (p rice-growing season by 21%. The amounts of iron, manganese, and arsenic that leached into the drainage water before full rice heading were also reduced by the NB water. Regardless of the water type, weekly-measured CH4 flux was linearly correlated with the leached iron concentration during the rice-growing season (r = 0.74, p pots without rice plants, soil reduction was not enhanced, regardless of the water type. The results indicate that NB water reduced CH4 emission and arsenic dissolution through an oxidative shift of the redox conditions in the flooded soil. We propose the use of NB water as a tool for controlling redox conditions in flooded paddy soils.

  15. Effect of Cold-Water Irrigation on Grain Quality Traits in japonica Rice Varieties from Yunnan Province, China

    Directory of Open Access Journals (Sweden)

    Guo-zhen ZHAO

    2009-09-01

    Full Text Available The response of grain quality traits to cold-water irrigation and its correlation with cold tolerance were studied in 11 japonica rice varieties from Yunnan Province, China. The results indicated that the response of grain quality traits to the cold-water stress varied with rice varieties and grain quality traits. Under the cold-water stress, grain width, chalky rice rate, whiteness, 1000-grain weight, brown rice rate, taste meter value, peak viscosity, trough viscosity, breakdown viscosity and final viscosity significantly decreased, whereas grain length-width ratio, head rice rate, alkali digestion value, protein content and setback viscosity markedly increased. However, the other traits such as grain length, amylose content, milled rice rate, peak viscosity time and pasting temperature were not significantly affected by the cold-water stress. Significant correlations were discovered between phenotypic acceptability and cold response indices of taste meter value, protein content, peak viscosity and breakdown viscosity. Therefore, it would be very important to improve the cold tolerance of Yunnan rice varieties in order to stabilize and improve their eating quality.

  16. Study of the influence of stable cadmium on the transfer of zinc-65 in an ecosystem irrigated by submersion (irrigated rice field)

    International Nuclear Information System (INIS)

    Myttenaere, C.; Merlini, M.; Dabin, P.; Mousny, J.M.; Pozzi, G.; Bittel, R.

    1975-01-01

    Irrigation water contains varying amounts of stable cadmium from industrial disposal. The presence of this element is capable of modifying the transfer of and affecting the mechanisms of absorption of zinc-65, a radionuclide which is discharged into water by nuclear power stations. This type of interaction between a nuclear contaminant and a conventional contaminant was studied in a rice-field irrigated by submersion. This ecosystem was reproduced under controlled 'mini-rice-field' conditions: the water was enriched in stable zinc (1 ppm) and in stable cadmium (2,5x10 -3 ; 50x10 -3 ppm) so as to reproduce the actual conditions; the stable zinc was traced by means of zinc-65. Fish (20 Carassius auratus L.) were introduced into each compartment of the ecosystem. Samples of irrigation water and surface water were taken during cultivation, and at the end of cultivation the content of stable zinc, radioactive zinc and stable cadmium was determined in each component of the ecosystem. The results show the important influence of a conventional contaminant on the transfer of a radionuclide and justify the use of the term 'associate contaminant' to describe it. (author)

  17. Effects of rice straw, biochar and mineral fertiliser on methane (CH4) and nitrous oxide (N2O) emissions from rice (Oryza sativa L.) grown in a rain-fed lowland rice soil of Cambodia

    DEFF Research Database (Denmark)

    Ly, Proyuth; Duong, Quynh Vu; Jensen, Lars Stoumann

    2015-01-01

    -control, rice straw (RS) and biochar (BC). Compound fertiliser was applied to all treatments. Rice was grown in columns packed with a paddy soil from Cambodia. Results revealed faster mineralisation of organic carbon (RS and BC) when applied in water-saturated conditions lasting for 2 weeks instead of flooding...

  18. Irrigation initiation timing in soybean grown on sandy soils in Northeast Arkansas

    Science.gov (United States)

    Irrigation initiation timing was evaluated in furrow-irrigated soybean field with sandy soils in Mississippi County, AR. A major objective of this 2015 study was to validate and expand irrigation timing recommendations that pair plant growth measures with weather cues including use of local weather ...

  19. Ethanol fermentation with Kluyveromyces marxianus from Jerusalem artichoke grown in salina and irrigated with a mixture of seawater and freshwater.

    Science.gov (United States)

    Yuan, W J; Zhao, X Q; Ge, X M; Bai, F W

    2008-12-01

    To study fuel ethanol fermentation with Kluyveromyces marxianus ATCC8554 from Jerusalem artichoke (Helianthus tuberosus) grown in salina and irrigated with a mixture of seawater and freshwater. The growth and ethanol fermentation of K. marxianus ATCC8554 were studied using inulin as substrate. The activity of inulinase, which attributes to the hydrolysis of inulin, the main carbohydrate in Jerusalem artichoke, was monitored. The optimum temperatures were 38 degrees C for growth and inulinase production, and 35 degrees C for ethanol fermentation. Aeration was not necessary for ethanol fermentation with the K. marxianus from inulin. Then, the fresh Jerusalem artichoke tubers grown in salina and irrigated with 25% and 50% seawater were further examined for ethanol fermentation with the K. marxianus, and a higher ethanol yield was achieved for the Jerusalem artichoke tuber irrigated with 25% seawater. Furthermore, the dry meal of the Jerusalem artichoke tubers irrigated with 25% seawater was examined for ethanol fermentation at three solid concentrations of 200, 225 and 250 g l(-1), and the highest ethanol yield of 0.467, or 91.5% of the theoretical value of 0.511, was achieved for the slurry with a solid concentration of 200 g l(-1). Halophilic Jerusalem artichoke can be used for fuel ethanol production. Halophilic Jerusalem artichoke, not competing with grain crops for arable land, is a sustainable feedstock for fuel ethanol production.

  20. Effects of Irrigation Methods on the Growth of Petunia Grown in Heat Fusion Polyester Fiber Hardened Medium without Polythylene Pot

    OpenAIRE

    後藤, 丹十郎; 島, 浩二; 東, 千里; 森下, 照久; 藤井, 一徳; 元岡, 茂治

    2006-01-01

    Recenty, polyethylene pots(PP) present a significant environmental issue for waste disposal. To develop bedding plant production system without PP, properties of compacted medium hardened by heat fusion polyester fiber were investigated. Effects of irrigation methods on the growth of vegetative propagated petunia grown in medium without PP were investigated. The effect of medium type was not as significant as the difference in water loss per pot. Water loss per pot of medium without PP was ab...

  1. Scale Effects of Water Saving on Irrigation Efficiency: Case Study of a Rice-Based Groundwater Irrigation System on the Sanjiang Plain, Northeast China

    Directory of Open Access Journals (Sweden)

    Haorui Chen

    2017-12-01

    Full Text Available This research analyzed the scale effect of water saving in Bielahonghe (BLH Basin, a rice-cultivating district on the Sanjiang Plain, Northeast China. Water budgets with different surface irrigation water supply ratios and water-saving measures were simulated with a semi-distributed water balance model. PFnws, representing the ratio of rice evapotranspiration to net water supply (the total amount of irrigation and precipitation minus the amount of water reused, was employed to assess the water use efficiency. Seven spatial scales (noted from S1 to S7, ranging from a single field (317.87 ha to the whole basin (about 100,800 ha were determined. PFnws values were quantified across scales and several water-saving measures, including water-saving irrigation regimes, canal lining, and a reduction of the surface water supply ratio (SWSR. The results indicated that PFnws increased with scale and could be calculated by a fitted power function (PFnws = 0.736Area0.033, R2 = 0.58. Furthermore, PFnws increased most prominently when the scale increased from S1 to S2. The water-saving irrigation regime (WSIR had the most substantial water-saving effect (WSE at S1. Specifically, PFnws improved by 21.2% at S1 when high-intensity WSIR was applied. Additionally, the WSE values of S3 and S5 were slightly higher than at other scales when the branch canal water delivery coefficient increased from 0.65 to 0.80 through canal lining. Furthermore, the PFnws at each scale varied with SWSR. Specifically, PFnws from S3 to S7 improved as SWSR decreased from 0.4 to 0.3 but remained approximately constant when SWSR decreased from 0.3 to 0.

  2. Interactive Effects of Elevated CO2 and N Fertilization on Yield and Quality of Tomato Grown Under Reduced Irrigation Regimes

    Directory of Open Access Journals (Sweden)

    Zhenhua Wei

    2018-03-01

    Full Text Available The interactive effects of CO2 elevation, N fertilization, and reduced irrigation regimes on fruit yield (FY and quality in tomato (Solanum lycopersicum L. were investigated in a split-root pot experiment. The plants were grown in two separate climate-controlled greenhouse cells at atmospheric [CO2] of 400 and 800 ppm, respectively. In each cell, the plants were fertilized at either 100 or 200 mg N kg-1 soil and were either irrigated to full water holding capacity [i.e., a volumetric soil water content of 18%; full irrigation (FI], or using 70% water of FI to the whole pot [deficit irrigation (DI] or alternately to only half of the pot [partial root-zone irrigation (PRI]. The yield and fruit quality attributes mainly from sugars (sucrose, fructose, and glucose and organic acids (OAs; citric acid and malic acid to various ionic (NH4+, K+, Mg2+, Ca2+, NO3-, SO42-, and PO43- concentrations in fruit juice were determined. The results indicated that lower N supply reduced fruit number and yield, whereas it enhanced some of the quality attributes of fruit as indicated by greater firmness and higher concentrations of sugars and OAs. Elevated [CO2] (e[CO2] attenuated the negative influence of reduced irrigation (DI and PRI on FY. Principal component analysis revealed that the reduced irrigation regimes, especially PRI, in combination with e[CO2] could synergistically improve the comprehensive quality of tomato fruits at high N supply. These findings provide useful knowledge for sustaining tomato FY and quality in a future drier and CO2-enriched environment.

  3. A study of technetium 99 uptake by irrigated rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    Vandecasteele, C.M.; De Becker, R.; Tang Van Hai; Myttenaere, C.

    1983-01-01

    The absorption of technetium 99 (an important fission product which can be released in the environment at different steps of the nuclear fuel cycle) by rice (Oryza sativa L.) was studied in nutrient solutions and in flooded soils with contaminated water. The absorption kinetics established in water culture (continuous flowing system) for 99 Tc concentrations ranging from 0.017 to 17 μCi.I - 1 revealed two phases: the former corresponds to the diffusion in the apparent free spaces and the second, which is linear, represents the transfer of 99 Tc from the external medium into the root cells as well as its translocation to the leaves. The study of the desorption mechanism confirmed the existence of these compartments, the second one containing more than 95% of the total activity of the plant. The biological half-life of 99 Tc of the second compartment is so high that decontamination of the plant may not be expected. In soils, toxicity symptoms were observed for a 99 Tc water concentration of 17 μCi.I - 1 . The transfer factors calculated in irrigated soils are very high (>10 3 for the leafy shoots) and the distribution of 99 Tc between the different organs waries with the concentration used. More than 90% of 99 Tc is found in the leafy shoots meanwhile 1% of the plant total activity is only found in the caryopses [fr

  4. Anopheles larval abundance and diversity in three rice agro-village complexes Mwea irrigation scheme, central Kenya

    Directory of Open Access Journals (Sweden)

    Mwangangi Joseph M

    2010-08-01

    Full Text Available Abstract Background The diversity and abundance of Anopheles larvae has significant influence on the resulting adult mosquito population and hence the dynamics of malaria transmission. Studies were conducted to examine larval habitat dynamics and ecological factors affecting survivorship of aquatic stages of malaria vectors in three agro-ecological settings in Mwea, Kenya. Methods Three villages were selected based on rice husbandry and water management practices. Aquatic habitats in the 3 villages representing planned rice cultivation (Mbui Njeru, unplanned rice cultivation (Kiamachiri and non-irrigated (Murinduko agro-ecosystems were sampled every 2 weeks to generate stage-specific estimates of mosquito larval densities, relative abundance and diversity. Records of distance to the nearest homestead, vegetation coverage, surface debris, turbidity, habitat stability, habitat type, rice growth stage, number of rice tillers and percent Azolla cover were taken for each habitat. Results Captures of early, late instars and pupae accounted for 78.2%, 10.9% and 10.8% of the total Anopheles immatures sampled (n = 29,252, respectively. There were significant differences in larval abundance between 3 agro-ecosystems. The village with 'planned' rice cultivation had relatively lower Anopheles larval densities compared to the villages where 'unplanned' or non-irrigated. Similarly, species composition and richness was higher in the two villages with either 'unplanned' or limited rice cultivation, an indication of the importance of land use patterns on diversity of larval habitat types. Rice fields and associated canals were the most productive habitat types while water pools and puddles were important for short periods during the rainy season. Multiple logistic regression analysis showed that presence of other invertebrates, percentage Azolla cover, distance to nearest homestead, depth and water turbidity were the best predictors for Anopheles mosquito larval

  5. Rice Field Geochemistry and Hydrology: An Explanation for Why Groundwater Irrigated Fields in Bangladesh are Net Sinks of Arsenic from Groundwater

    Science.gov (United States)

    Neumann, Rebecca B.; St. Vincent, Allison P.; Roberts, Linda C.; Badruzzaman, A. Borhan M.; Ali, M. Ashraf; Harvey, Charles F.

    2011-01-01

    Irrigation of rice fields in Bangladesh with arsenic-contaminated groundwater transfers tens of cubic kilometers of water and thousands of tons of arsenic from aquifers to rice fields each year. Here we combine observations of infiltration patterns with measurements of porewater chemical composition from our field site in Munshiganj Bangladesh to characterize the mobility of arsenic in soils beneath rice fields. We find that very little arsenic delivered by irrigation returns to the aquifer, and that recharging water mobilizes little, if any, arsenic from rice field subsoils. Arsenic from irrigation water is deposited on surface soils and sequestered along flow paths that pass through bunds, the raised soil boundaries around fields. Additionally, timing of flow into bunds limits the transport of biologically available organic carbon from rice fields into the subsurface where it could stimulate reduction processes that mobilize arsenic from soils and sediments. Together, these results explain why groundwater irrigated rice fields act as net sinks of arsenic from groundwater. PMID:21332196

  6. Influence of a deficit irrigation regime during ripening on berry composition in grapevines (Vitis vinifera L.) grown in semi-arid areas.

    Science.gov (United States)

    López, María-Isabel; Sánchez, María-Teresa; Díaz, Antonio; Ramírez, Pilar; Morales, José

    2007-11-01

    A study was made of the effects of irrigation management strategies during ripening on the quality of Spanish field-grown grapevine (Vitis vinifera L.) cultivars (Baladi, Airén, Montepila, Muscat Blanc à Petits Grains and Pedro Ximénez) grown under the "Montilla-Moriles" Appellation of Origin in Cordoba, Spain. From 1999 to 2002, two water-availability regimes were established: irrigation and non-irrigation. The study aimed to ascertain the effect of irrigation on berry development and ripening, and hence on grape juice quality. Changes in phenological stages, vegetative growth, vineyard yield, berry weight, total soluble solids, titrable acidity, pH, tartaric acid, malic acid, and potassium content were monitored. No significant differences were noted in phenological phases between the non-irrigation and deficit irrigation regimes. The Ravaz index, pruning weight, vineyard yield and berry weight were significantly higher in all varieties and years under deficit irrigation. Deficit irrigation induced higher titrable acidity, higher malic acid and potassium contents and a lower pH, but had no significant effects on berry sugar accumulation or tartaric acid content. Deficit irrigation thus appears to be a promising technique for the production of quality young wines in semi-arid areas.

  7. Translocations of 2,4-D-14C Herbicides In Weed And Rice Plant On Irrigated Rice Field System

    International Nuclear Information System (INIS)

    Chairul, Sofnie M.; Idawati; Mulyadi

    2000-01-01

    The investigation of translocation 2,4-D herbicides using 14 C as tracer on irradiated rice plant system. Condition of the soil was two kinds, that is normal soil and soil 30% up normal. The soil of rice field was spray with 1μCi of 2,4-D non labelled, one week after planting. A part of rice plant and weed was determined the radioactivity after 0, 2, 4, 8, and 10 weeks after spraying. The result showed that radioactivity maximum after zero week was in root and leaf of weeds, the second weeks in root of rice, the forth weeks in rice stick, and eighth weeks in leaf of rice. This result occur at normal condition soil of solid 30 % up normal soil. The residues of 2.4-D in rice was 4,24x10 -3 ppb at normal soil and 3.16x10 -3 ppb at solid 30% up normal soil. This result still lower than rate of WHO/FAO, that is 0,05 ppm

  8. Effect of Alternative Irrigation Strategies on Yield and Quality of Fiesta Raisin Grapes Grown in California

    Directory of Open Access Journals (Sweden)

    Isabel Abrisqueta

    2018-04-01

    Full Text Available Traditionally, grapes are fully irrigated, but alternative irrigation strategies to reduce applied irrigation water may be necessary in the future as occurrences of drought increase. This study was conducted in the San Joaquin Valley (SJV of California from 2012 to 2014. Three irrigation treatments were used to study the effects on the yield and quality of Fiesta grapes. The treatments included: grower irrigation (GI weekly irrigation lasting for approximately 65 h; sustained deficit (SD equal to 80% of the GI treatment; and regulated deficit (RD equal to 50% of the GI until fruit set when it was increased to 80% of the GI through harvest and reduced to 50% of the GI after harvest. Average water use across treatments was ≈489 mm. Average yield across all treatments was 7.9 t ha−1, 9.1 t ha−1 and 11.8 t ha−1 in 2012, 2013, and 2014, respectively. Yield was sustained in SD and RD, with up to a 20% reduction in applied water use compared to GI. There were no differences in raisin quality and grade among any of the treatments in any year. The percentage of substandard grapes decreased from an average of 12.6% in 2012 to 3.6% in 2013 and 2014. Growers may use a sustained deficit approach during periods of limited water availability to minimize the effect on yield.

  9. Economics of weed suppressive rice cultivars in flood- and furrow-irrigated systems

    Science.gov (United States)

    Weeds are a major constraint to rice production. In the U.S, weeds in rice are controlled primarily with synthetic herbicides. Intensive herbicide application in rice also has many potential drawbacks, resulting in environmental pollution, human health concerns, and development of weed resistance. B...

  10. Water management for controlling the breeding of Anopheles mosquitoes in rice irrigation schemes in Kenya

    DEFF Research Database (Denmark)

    Mutero, C M; Blank, H; Konradsen, F

    2000-01-01

    abundance fluctuated throughout the 12-week sampling period. The highest larval densities were recorded in the 3 weeks after transplanting the rice seedlings. Afterwards, larval numbers dropped dramatically as the height of rice plants increased. Rice yields at harvest did not show statistically significant...

  11. Mapping suitability of rice production systems for mitigation: Strategic approach for prioritizing improved irrigation management across scales

    Science.gov (United States)

    Wassmann, Reiner; Sander, Bjoern Ole

    2016-04-01

    After the successful conclusion of the COP21 in Paris, many developing countries are now embracing the task of reducing emissions with much vigor than previously. In many countries of South and South-East Asia, the agriculture sector constitutes a vast share of the national GHG budget which can mainly be attributed to methane emissions from flooded rice production. Thus, rice growing countries are now looking for tangible and easily accessible information as to how to reduce emissions from rice production in an efficient manner. Given present and future food demand, mitigation options will have to comply with aim of increasing productivity. At the same time, limited financial resources demand for strategic planning of potential mitigation projects based on cost-benefit ratios. At this point, the most promising approach for mitigating methane emissions from rice is an irrigation technique called Alternate Wetting and Drying (AWD). AWD was initially developed for saving water and subsequently, represents an adaptation strategy in its own right by coping with less rainfall. Moreover, AWD also reduces methane emissions in a range from 30-70%. However, AWD is not universally suitable. It is attractive to farmers who have to pump water and may save fuel under AWD, but renders limited incentives in situations where there is no real pressing water scarcity. Thus, planning for AWD adoption at larger scale, e.g. for country-wide programs, should be based on a systematic prioritization of target environments. This presentation encompasses a new methodology for mapping suitability of water-saving in rice production - as a means for planning adaptation and mitigation programs - alongside with preliminary results. The latter comprises three new GIS maps on climate-driven suitability of AWD in major rice growing countries (Philippines, Vietnam, Bangladesh). These maps have been derived from high-resolution data of the areal and temporal extent of rice production that are now

  12. Mitigating global warming potentials of methane and nitrous oxide gases from rice paddies under different irrigation regimes.

    Science.gov (United States)

    Ali, Muhammad Aslam; Hoque, M Anamul; Kim, Pil Joo

    2013-04-01

    A field experiment was conducted in Bangladesh Agricultural University Farm to investigate the mitigating effects of soil amendments such as calcium carbide, calcium silicate, phosphogypsum, and biochar with urea fertilizer on global warming potentials (GWPs) of methane (CH4) and nitrous oxide (N2O) gases during rice cultivation under continuous and intermittent irrigations. Among the amendments phosphogypsum and silicate fertilizer, being potential source of electron acceptors, decreased maximum level of seasonal CH4 flux by 25-27 % and 32-38 % in continuous and intermittent irrigations, respectively. Biochar and calcium carbide amendments, acting as nitrification inhibitors, decreased N2O emissions by 36-40 % and 26-30 % under continuous and intermittent irrigations, respectively. The total GWP of CH4 and N2O gases were decreased by 7-27 % and 6-34 % with calcium carbide, phosphogypsum, and silicate fertilizer amendments under continuous and intermittent irrigations, respectively. However, biochar amendments increased overall GWP of CH4 and N2O gases.

  13. Soil to rice transfer factors for 226Ra, 228Ra, 210Pb, 40K and 137Cs: a study on rice grown in India

    International Nuclear Information System (INIS)

    Karunakara, N.; Rao, Chetan; Ujwal, P.; Yashodhara, I.; Kumara, Sudeep; Ravi, P.M.

    2013-01-01

    India is the second largest producer of rice (Oryza sativa L.) in the world and rice is an essential component of the diet for a majority of the population in India. However, detailed studies aimed at the evaluation of radionuclide transfer factors (F v ) for the rice grown in India are almost non-existent. This paper presents the soil to rice transfer factors for natural ( 226 Ra, 228 Ra, 40 K, and 210 Pb) and artificial ( 137 Cs) radionuclides for rice grown in natural field conditions on the West Coast of India. A rice field was developed very close to the Kaiga nuclear power plant and the water required for this field was drawn from the cooling water discharge canal of the power plant. For a comparative study of the radionuclide transfer factors, rice samples were also collected from the rice fields of nearby villages. The study showed that the 226 Ra and 228 Ra activity concentrations were below detection levels in different organs of the rice plant. The soil to un-hulled rice grain 40 K transfer factor varied in the range of 6.5 × 10 −1 to 2.9 with a mean of 0.15 × 10 1 , and of 210 Pb varied in the range of −2 to 8.1 × 10 −1 with a mean of 1.4 × 10 −1 , and of 137 Cs varied in the range of 6.6 × 10 −2 to 3.4 × 10 −1 with a mean of 2.1 × 10 −1 . The mean values of un-hulled grain to white rice processing retention factors (F r ) were 0.12 for 40 K, 0.03 for 210 Pb, and 0.14 for 137 Cs. Using these processing retention factors, the soil to white rice transfer factors were estimated and these were found to have mean values of 1.8 × 10 −1 , 4.2 × 10 −3 , and 3.0 × 10 −2 for 40 K, 210 Pb, and 137 Cs, respectively. The study has shown that the transfer of 40 K was higher for above the ground organs than for the root, but 210 Pb and 137 Cs were retained in the root and their transfer to above the ground organs of the rice plant is significantly lower. -- Highlights: ► Soil to rice (Oryza sativa L.) transfer factors for radionuclides

  14. The impact of elevated CO2 and temperature on grain quality of rice grown under open-air field conditions.

    Science.gov (United States)

    Jing, Liquan; Wang, Juan; Shen, Shibo; Wang, Yunxia; Zhu, Jianguo; Wang, Yulong; Yang, Lianxin

    2016-08-01

    Rising atmospheric CO2 is accompanied by global warming. However, interactive effects of elevated CO2 and temperature have not been well studied on grain quality of rice. A japonica cultivar was grown in the field using a free-air CO2 enrichment facility in combination with a canopy air temperature increase system in 2014. The gas fumigation (200 µmol mol(-1) above ambient CO2 ) and temperature increase (1 °C above ambient air temperature) were performed from tillering until maturity. Compared with the control (ambient CO2 and air temperature), elevated CO2 increased grain length and width as well as grain chalkiness but decreased protein concentrations. In contrast, the increase in canopy air temperature had less effect on these parameters except for grain chalkiness. The starch pasting properties of rice flour and taste analysis of cooked rice indicated that the palatability of rice was improved by CO2 and/or temperature elevation, with the combination of the two treatments showing the most significant changes compared with ambient rice. It is concluded that projected CO2 in 2050 may have larger effects on rice grain quality than the projected temperature increase. Although deterioration in milling suitability, grain appearance and nutritional quality can be expected, the taste of cooked rice might be better in the future environment. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  15. An integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes.

    Science.gov (United States)

    Chiaradia, Enrico Antonio; Facchi, Arianna; Masseroni, Daniele; Ferrari, Daniele; Bischetti, Gian Battista; Gharsallah, Olfa; Cesari de Maria, Sandra; Rienzner, Michele; Naldi, Ezio; Romani, Marco; Gandolfi, Claudio

    2015-09-01

    The cultivation of rice, one of the most important staple crops worldwide, has very high water requirements. A variety of irrigation practices are applied, whose pros and cons, both in terms of water productivity and of their effects on the environment, are not completely understood yet. The continuous monitoring of irrigation and rainfall inputs, as well as of soil water dynamics, is a very important factor in the analysis of these practices. At the same time, however, it represents a challenging and costly task because of the complexity of the processes involved, of the difference in nature and magnitude of the driving variables and of the high variety of field conditions. In this paper, we present the prototype of an integrated, multisensor system for the continuous monitoring of water dynamics in rice fields under different irrigation regimes. The system consists of the following: (1) flow measurement devices for the monitoring of irrigation supply and tailwater drainage; (2) piezometers for groundwater level monitoring; (3) level gauges for monitoring the flooding depth; (4) multilevel tensiometers and moisture sensor clusters to monitor soil water status; (5) eddy covariance station for the estimation of evapotranspiration fluxes and (6) wireless transmission devices and software interface for data transfer, storage and control from remote computer. The system is modular and it is replicable in different field conditions. It was successfully applied over a 2-year period in three experimental plots in Northern Italy, each one with a different water management strategy. In the paper, we present information concerning the different instruments selected, their interconnections and their integration in a common remote control scheme. We also provide considerations and figures on the material and labour costs of the installation and management of the system.

  16. Population dynamics and breeding patterns of multimammate mouse, Mastomys natalensis (Smith 1834), in irrigated rice fields in eastern Tanzania.

    Science.gov (United States)

    Mulungu, Loth S; Ngowo, Victoria; Mdangi, Mashaka; Katakweba, Abdul S; Tesha, Protas; Mrosso, Furaha P; Mchomvu, Mary; Sheyo, Paul M; Kilonzo, Bukhet S

    2013-03-01

    Multimammate mice are the most important vertebrate pests in Sub-Saharan Africa and are also reservoirs of many zoonotic diseases, including sylvan plague. This study investigated the population dynamics and breeding patterns of this mouse in irrigated rice cropping systems in eastern Tanzania. The multimammate mouse, Mastomys natalensis, population varied with habitat and months. Fallow land had a more abundant population than rice fields. The highest population peak was observed during the dry season from July to October. Mastomys natalensis is sexually active throughout the year in the study area, although it reaches the highest level in June and December when rice is at the maturity stage. This suggests that breeding is highly influenced by the presence of a rice crop in both seasons. More juvenile individuals were recorded in August and September, indicating that they were produced in the previous breeding months. The sex ratio of M. natalensis was not skewed to either males or females, indicating that it was at parity. Rodent population dynamics during the study periods in all habitats indicated that high birth rates accounted for the rapid population growth and turnover. Regular control and sustainable operations are thus essential if rodent pest populations are to be kept within tolerable limits. Copyright © 2012 Society of Chemical Industry.

  17. Risk assessment and vertical distribution of thallium in paddy soils and uptake in rice plants irrigated with acid mine drainage.

    Science.gov (United States)

    Huang, Xuexia; Li, Ning; Wu, Qihang; Long, Jianyou; Luo, Dinggui; Zhang, Ping; Yao, Yan; Huang, Xiaowu; Li, Dongmei; Lu, Yayin; Liang, Jianfeng

    2016-12-01

    The objective of this paper is to assess the influence of irritating paddy fields with acid mine drainage containing thallium (Tl) to rice plant-soil system and potential health risks for local residents. Vertical distribution of Tl, pH, organic matter (OM), and cation exchange capacity (CEC) in 24 paddy soil profiles around Yunfu pyrite mine area was investigated. Rice plant samples were collected from the corresponding soil sampling site. The results showed that Tl concentrations in paddy soils at 0-60 cm depth range from 3.07 to 9.42 mg kg -1 , with a mean of 5.74 mg kg -1 , which were significantly higher than the background value of soil in China (0.58 mg kg -1 ). On the whole, Tl contents in paddy soil profiles increased quickly with soil depth from 0 to 30 cm and decreased slowly with soil depth from 30 to 60 cm. The soil Tl content was significant negatively correlated with soil pH. The mean content of Tl in the root, stem, leaf, and rice was 4.36, 1.83, 2.74, and 1.42 mg kg -1 , respectively, which exceeded the proposed permissible limits for foods and feedstuffs in Germany. The Tl content in various tissues of the rice plants followed the order root > leaf > stem (rice), which suggested that most Tl taken up by rice plants retained in the root, and a little migrated to the leaf, stem, and rice. Correlation analysis showed that Tl content in root was significant positively correlated with Tl content in leaf and rice. The ranges of hazard quotient (HQ) values were 4.08∼24.50 and 3.84∼22.38 for males and females, respectively. Males have higher health risk than females in the same age group. In childhood age groups (2 to <21 years) and adult age groups (21 to <70 years), the highest health risk level was observed in the 11 to 16 age group and 21 to 50 age group, respectively. The findings indicated that regular irrigation with Tl-bearing acid mine drainage led to considerable contamination of Tl in paddy soil and rice plant. Local government

  18. Interaction of different irrigation strategies and soil textures on the nitrogen uptake of field grown potatoes

    DEFF Research Database (Denmark)

    Ahmadi, S.H.; Andersen, M.N.; Lærke, P.E.

    2011-01-01

    received 65% of FI after tuber bulking and lasted for six weeks until final harvest. Results showed that the irrigation treatments were not significantly different in terms of N uptake in the tubers, shoot, and whole crop. However, there was a statistical difference between the soil textures where plants...... in the loamy sand had the highest amount of N uptake. The interaction between irrigation treatments and soil textures was significant, and implied that under non-limiting water conditions, loamy sand is the suitable soil for potato production because plants can take up sufficient amounts of N and it could...... potentially lead to higher yield. However, under limited water conditions and applying water-saving irrigation strategies, sandy loam and coarse sand are better growth media because N is more available for the potatoes. The simple yield prediction model was developed that could explains ca. 96...

  19. UV-B effects on crops: response of the irrigated rice ecosystem

    International Nuclear Information System (INIS)

    Olszyk, D.; Dai, Q.; Teng, P.; Leung, H.; Luo, Y.; Peng, S.

    1996-01-01

    Increasing ultraviolet-B (UV-B) radiation resulting from depletion of the stratospheric ozone layer could have damaging effects on crops. This paper reviews recent findings on direct effects of UV-B on rice growth and yield as well as indirect effects via impacts on other organisms in the rice (Oryza sativa) agroecosystem. The findings are based on research by scientists at the International Rice Research Institute (IRRI) in Los Baños, the Philippines, and their collaborators in China and the United States; with comparison to research by scientists in other countries. Current results indicate that while enhanced UV-B directly impacts many aspects of rice growth, physiology, and biochemistry under controlled phytotron conditions; in general rice growth and yield are not affected under natural field conditions. The difference in response may be related both to the levels of UV-B exposure used in phytotron vs. field studies and the lower ratio of UV-A to UV-B in the phytotron compared to field. In terms of indirect effects on rice blast disease, enhanced UV-B affected both the fungus itself (Pyricularia grisea) and the susceptibility of the rice plant to the fungus. Based on these data, simulation models estimated potential impacts of higher UV-B levels on blast severity and rice yield in different countries of southeast and east Asia. Ultimately, results from rice studies can be used to identify strategies to minimize any negative effects of UV-B on rice productivity

  20. Mechanisms of Fe biofortification and mitigation of Cd accumulation in rice (Oryza sativa L.) grown hydroponically with Fe chelate fertilization.

    Science.gov (United States)

    Chen, Zhe; Tang, Ye-Tao; Zhou, Can; Xie, Shu-Ting; Xiao, Shi; Baker, Alan J M; Qiu, Rong-Liang

    2017-05-01

    Cadmium contaminated rice from China has become a global food safety issue. Some research has suggested that chelate addition to substrates can affect metal speciation and plant metal content. We investigated the mitigation of Cd accumulation in hydroponically-grown rice supplied with EDTANa 2 Fe(II) or EDDHAFe(III). A japonica rice variety (Nipponbare) was grown in modified Kimura B solution containing three concentrations (0, 10, 100 μΜ) of the iron chelates EDTANa 2 Fe(II) or EDDHAFe(III) and 1 μΜ Cd. Metal speciation in solution was simulated by Geochem-EZ; growth and photosynthetic efficiency of rice were evaluated, and accumulation of Cd and Fe in plant parts was determined. Net Cd fluxes in the meristematic zone, growth zone, and maturation zone of roots were monitored by a non-invasive micro-test technology. Expression of Fe- and Cd-related genes in Fe-sufficient or Fe-deficient roots and leaves were studied by QRT-PCR. Compared to Fe deficiency, a sufficient or excess supply of Fe chelates significantly enhanced rice growth by elevating photosynthetic efficiency. Both Fe chelates increased the Fe content and decreased the Cd content of rice organs, except for the Cd content of roots treated with excess EDDHAFe(III). Compared to EDDHAFe(III), EDTANa 2 Fe(II) exhibited better mitigation of Cd accumulation in rice by generating the EDTANa 2 Cd complex in solution, decreasing net Cd influx and increasing net Cd efflux in root micro-zones. Application of EDTANa 2 Fe(II) and EDDHAFe(III) also reduced Cd accumulation in rice by inhibiting expression of genes involved in transport of Fe and Cd in the xylem and phloem. The 'win-win' situation of Fe biofortification and Cd mitigation in rice was achieved by application of Fe chelates. Root-to-stem xylem transport of Cd and redistribution of Cd in leaves by phloem transport can be regulated in rice through the use of Fe chelates that influence Fe availability and Fe-related gene expression. Fe fertilization

  1. Metaproteomic identification of diazotrophic methanotrophs and their localization in root tissues of field-grown rice plants.

    Science.gov (United States)

    Bao, Zhihua; Okubo, Takashi; Kubota, Kengo; Kasahara, Yasuhiro; Tsurumaru, Hirohito; Anda, Mizue; Ikeda, Seishi; Minamisawa, Kiwamu

    2014-08-01

    In a previous study by our group, CH4 oxidation and N2 fixation were simultaneously activated in the roots of wild-type rice plants in a paddy field with no N input; both processes are likely controlled by a rice gene for microbial symbiosis. The present study examined which microorganisms in rice roots were responsible for CH4 oxidation and N2 fixation under the field conditions. Metaproteomic analysis of root-associated bacteria from field-grown rice (Oryza sativa Nipponbare) revealed that nitrogenase complex-containing nitrogenase reductase (NifH) and the alpha subunit (NifD) and beta subunit (NifK) of dinitrogenase were mainly derived from type II methanotrophic bacteria of the family Methylocystaceae, including Methylosinus spp. Minor nitrogenase proteins such as Methylocella, Bradyrhizobium, Rhodopseudomonas, and Anaeromyxobacter were also detected. Methane monooxygenase proteins (PmoCBA and MmoXYZCBG) were detected in the same bacterial group of the Methylocystaceae. Because these results indicated that Methylocystaceae members mediate both CH4 oxidation and N2 fixation, we examined their localization in rice tissues by using catalyzed reporter deposition-fluorescence in situ hybridization (CARD-FISH). The methanotrophs were localized around the epidermal cells and vascular cylinder in the root tissues of the field-grown rice plants. Our metaproteomics and CARD-FISH results suggest that CH4 oxidation and N2 fixation are performed mainly by type II methanotrophs of the Methylocystaceae, including Methylosinus spp., inhabiting the vascular bundles and epidermal cells of rice roots. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  2. Residue management increases fallow water conservation and yield deficit irrigated crops grown in rotation with wheat

    Science.gov (United States)

    No-tillage (NT) residue management provides cover to increase precipitation capture compared with disk tillage (DT) or in the absence of a cover crop. Therefore, NT has the potential to reduce irrigation withdrawals from the declining Ogallala Aquifer. In a 4-year study, we quantified DT and NT effe...

  3. Hyperspectral remote sensing analysis of short rotation woody crops grown with controlled nutrient and irrigation treatments

    Science.gov (United States)

    Jungho Im; John R. Jensen; Mark Coleman; Eric. Nelson

    2009-01-01

    Hyperspectral remote sensing research was conducted to document the biophysical and biochemical characteristics of controlled forest plots subjected to various nutrient and irrigation treatments. The experimental plots were located on the Savannah River Site near Aiken, SC. AISA hyperspectral imagery were analysed using three approaches, including: (1) normalized...

  4. Forms of trace arsenic, cesium, cadmium, and lead transported into river water for the irrigation of Japanese paddy rice fields

    Science.gov (United States)

    Nakaya, Shinji; Chi, Hai; Muroda, Kengo; Masuda, Harue

    2018-06-01

    In this study, we focus on the behavior of geogenic, toxic trace elements, particularly As, Cs, Cd, and Pb, during their transportation in two rivers for irrigation commonly used in monsoon Asia; one river originates from an active volcano, Mt. Asama, and the other originates from a currently inactive volcano, Yatsugatake Mountains in Nagano, Japan. These rivers were investigated to understand the role of river water as a pollutant of rice and other aquatic plants (via irrigation) and aquatic animals. The results indicated that the behavior of toxic trace elements in river water are likely controlled by their interactions with particulate Fe, Al, and Ti compounds. The majority of Pb and Cd is transported as particulate matter with Fe, Al, and Ti, while the majority of As is transported in the dissolved form, predominantly as arsenate, with low abundance of particulate matter. Cs is transported either as the dissolved form or as particulate matter in both rivers. The investigated elements are transported in the rivers as particulate and dissolved forms, and the ratio of these forms is controlled by the pH and presence of particulate Fe, Al, and Ti phases in the river water. With respect to Cs in both rivers, the parameter governing the concentration and transportation of Cs, in the bimodal form (i.e., particulate and dissolved forms), through the river possibly shifts from sorption to pH by particulate Fe-Al-Ti, according to the abrupt increase in the concentration of Cs in the river. The chemical attraction of particulate Fe-Al-Ti for Cs is weaker than that for Pb and Cd, indicating that the lower electronegativity of Cs weakens the chemical attraction on a colloid for the competitive sorption with the other trace elements. The different relationships between As and Fe in the river and in the irrigation water and soil water, as well as those in paddy rice, suggested that As in paddy rice is not directly derived from As in the irrigation water from the river under

  5. KOEFISIEN TANAMAN PADI SAWAH PADA SISTEM IRIGASI HEMAT AIR Crop Coefficient for Paddy Rice Field under Water Saving Irrigation Systems

    Directory of Open Access Journals (Sweden)

    Joko Sujono

    2012-05-01

    Full Text Available Traditional irrigation for paddy rice is the leading of consumer of water, about 80 % of the water resource availabilityused for irrigation purpose. This phenomenon is related to the way how to estimate the crop water requirement where crop coefficient for paddy rice (k (Prosida is always greater than one starting from planting up to nearly harvesting. In this research, a number of water saving irrigations (WSI systems for paddy rice cultivation using pots such asalternate wetting and drying (AWD, shallow water depth with wetting and drying (SWD, semi-dry cultivation (SDC, system of rice intensification (SRI, and  AWD with mulch (AWD-Mul were applied. The amount of irrigated water and when it should be irrigated depend on evapotranspiration rate, soil moisture condition and the WSI system used. For this purpose, daily measurement of the pot weight was carried out. Crop coefficient (k  is then caluculated as a cratio between crop and reference evapotranspiration computed using Penman-Montheit  method. Results show that up to 45 days after transplanting, the k of WSI treatments were around half of the k (Prosida values currently used for computing the water requirement, whereas at the productive stage the k of WSI systems were relatively equal (AWD, SDC to or greater (SRI, SWD than the k (Prosida. Based on the the k values, the AWD and the SDC systems could save much water compared to the SRI or the SWD. Water saving could be increased by applying the AWD with mulch. ABSTRAK Irigasi padi sawah dengan sistem tradisional merupakan sistem irigasi  yang boros air, hampir 80 % sumber air yang ada untuk irigasi. Hal ini tidak terlepas dari perhitungan kebutuhan air tanaman dengan nilai koefisien tanaman (k menurut Standar Perencanaan Irigasi (Prosida selalu lebih besar dari satu mulai dari tanam hingga menjelang panen.Dalam penelitian ini beberapa metoda budidaya padi hemat air seperti alternate wetting and drying (AWD, shallow water depth

  6. Effects of water-saving irrigation practices and drought resistant rice variety on greenhouse gas emissions from a no-till paddy in the central lowlands of China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Ying; Ge, Junzhu; Tian, Shaoyang; Li, Shuya [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Nguy-Robertson, Anthony L. [Center for Advanced Land Management Information Technologies, School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE 68583-0973 (United States); Zhan, Ming, E-mail: zhanming@mail.hzau.edu.cn [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Cao, Cougui, E-mail: ccgui@mail.hzau.edu.cn [MOA Key Laboratory of Crop Physiology, Ecology and Cultivation (The Middle Reaches of Yangtze River), Huazhong Agricultural University, Wuhan, Hubei 430070 (China); College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China)

    2015-02-01

    As pressure on water resources increases, alternative practices to conserve water in paddies have been developed. Few studies have simultaneously examined the effectiveness of different water regimes on conserving water, mitigating greenhouse gases (GHG), and maintaining yields in rice production. This study, which was conducted during the drought of 2013, examined all three factors using a split-plot experiment with two rice varieties in a no-till paddy managed under three different water regimes: 1) continuous flooding (CF), 2) flooded and wet intermittent irrigation (FWI), and 3) flooded and dry intermittent irrigation (FDI). The Methane (CH{sub 4}) and nitrous oxide (N{sub 2}O) emissions were measured using static chamber-gas measurements, and the carbon dioxide (CO{sub 2}) emissions were monitored using a soil CO{sub 2} flux system (LI-8100). Compared with CF, FWI and FDI irrigation strategies reduced CH{sub 4} emissions by 60% and 83%, respectively. In contrast, CO{sub 2} and N{sub 2}O fluxes increased by 65% and 9%, respectively, under FWI watering regime and by 104% and 11%, respectively, under FDI managed plots. Although CO{sub 2} and N{sub 2}O emissions increased, the global warming potential (GWP) and greenhouse gas intensity (GHGI) of all three GHG decreased by up to 25% and 29% (p < 0.01), respectively, using water-saving irrigation strategies. The rice variety also affected yields and GHG emissions in response to different water regimes. The drought-resistance rice variety (HY3) was observed to maintain yields, conserve water, and reduce GHG under the FWI irrigation management compared with the typical variety (FYY299) planted in the region. The FYY299 only had significantly lower GWP and GHGI when the yield was reduced under FDI water regime. In conclusion, FWI irrigation strategy could be an effective option for simultaneously saving water and mitigating GWP without reducing rice yields using drought-resistant rice varieties, such as HY3

  7. Effect of rice hull mulch on nutrient concentration of fertilized irrigation water

    Science.gov (United States)

    Parboiled rice hulls are an effective mulch for controlling weeds in nursery containers. A layer of rice hulls between 1.25 and 2.5 cm deep has been shown to provide effective control of liverwort (Marchantia polymorpha), bittercress (Cardamine flexuosa), and creeping woodsorrel (Oxalis corniculata...

  8. Disentangling the effect of environmental factors on yield and nitrogen uptake of irrigated rice in Asia

    NARCIS (Netherlands)

    Jing, Q.; Bouman, B.A.M.; Keulen, van H.; Hengsdijk, H.; Cao, W.; Dai, T.

    2008-01-01

    Rice yield is the result of the interaction between genotype (cultivar characteristics), environment (climate and soil conditions), and management. Few studies have attempted to isolate the contribution of each of these factors. Here the rice growth model ORYZA2000 was used to analyse the variation

  9. Use of the rice husk as an alternative substrate for growing media on green walls drip irrigation

    Science.gov (United States)

    Andrey Rivas-Sánchez, Yair; Fátima Moreno-Pérez, María; Roldán Cañas, José

    2017-04-01

    In the last years, we have been looking for alternatives to traditional growing mediums for green walls. Commercially available systems for green walls are commonly made with Sphagnum, rock wool or polymers that are unsustainable materials. In the design of the green wall, local components such as agricultural by-products should be considered more often. The objective of this research is to use alternative materials available in Andalusia that are suitable for use as a growing medium in green walls, using organic residues generated by agriculture as in this case the rice husk, compared to conventional and used materials as a growing media in green walls such as coconut fiber and rock wool. The physical-chemical characteristics of the water were analyzed through the collection of excess irrigation water, after passing through the prototypes of green walls, installed in the Rabanales Campus of the University of Córdoba between April and July 2016 and thus observe the feasibility of using rice husk as an alternative material. The 16 mm diameter irrigation pipes are at the top and middle of each module, with 12 adjustable drippers of 4 l / h for each module, 72 drippers in the whole experimental green wall prototype installed at every 15 centimeters of tube. Two different species of plant material (Lampranthus spectabilis) and (Lavandula stoechas), were selected, taking into account the solar exposition of the place of establishment of the prototype of the green wall and the easy acquisition of these plants in the region. Water samples were collected every day twice a day for 10 weeks of the experiment, taking a sample of the surplus runoff water from six green wall prototypes.PH 40 - pH - conductivity - TDS - temperature, CRISON. Differences in pH, electrical conductivity, turbidity and total solids of the treatments were examined by ANOVA with the test of normality and homogeneity of variances. It was observed that the substrates used in the prototypes of the

  10. Irrigation with oxygen-nanobubble water can reduce methane emission and arsenic dissolution in a flooded rice paddy

    International Nuclear Information System (INIS)

    Minamikawa, Kazunori; Makino, Tomoyuki; Tago, Kanako; Hayatsu, Masahito; Takahashi, Masayoshi

    2015-01-01

    A remarkable feature of nanobubbles (<10 –6 m in diameter) is their long lifetime in water. Supplying oxygen-nanobubbles (NBs) to continuously flooded paddy soil may retard the development of reductive conditions, thereby reducing the emission of methane (CH 4 ), a potent greenhouse gas, and dissolution of arsenic, an environmental load. We tested this hypothesis by performing a pot experiment and measuring redox-related variables. The NBs were introduced into control water (with properties similar to those of river water) using a commercially available generator. Rice (Oryza sativa L.) growth did not differ between plants irrigated with NB water and those irrigated with control water, but NB water significantly (p < 0.05) reduced cumulative CH 4 emission during the rice-growing season by 21%. The amounts of iron, manganese, and arsenic that leached into the drainage water before full rice heading were also reduced by the NB water. Regardless of the water type, weekly-measured CH 4 flux was linearly correlated with the leached iron concentration during the rice-growing season (r = 0.74, p < 0.001). At the end of the experiment, the NB water significantly lowered the soil pH in the 0–5 cm layer, probably because of the raised redox potential. The population of methanogenic Archaea (mcrA copy number) in the 0–5 cm layer was significantly increased by the NB water, but we found no correlation between the mcrA copy number and the cumulative CH 4 emission (r = –0.08, p = 0.85). In pots without rice plants, soil reduction was not enhanced, regardless of the water type. The results indicate that NB water reduced CH 4 emission and arsenic dissolution through an oxidative shift of the redox conditions in the flooded soil. We propose the use of NB water as a tool for controlling redox conditions in flooded paddy soils. (letter)

  11. Mapping cropping patterns in irrigated rice fields in West Java: Towards mapping vulnerability to flooding using time-series MODIS imageries

    Science.gov (United States)

    Sianturi, Riswan; Jetten, V. G.; Sartohadi, Junun

    2018-04-01

    Information on the vulnerability to flooding is vital to understand the potential damages from flood events. A method to determine the vulnerability to flooding in irrigated rice fields using the Enhanced Vegetation Index (EVI) was proposed in this study. In doing so, the time-series EVI derived from time-series 8 day 500 m spatial resolution MODIS imageries (MOD09A1) was used to generate cropping patterns in irrigated rice fields in West Java. Cropping patterns were derived from the spatial distribution and phenology metrics so that it is possible to show the variation of vulnerability in space and time. Vulnerability curves and cropping patterns were used to determine the vulnerability to flooding in irrigated rice fields. Cropping patterns capture the shift in the vulnerability, which may lead to either an increase or decrease of the degree of damage in rice fields of origin and other rice fields. The comparison of rice field areas between MOD09A1 and ALOS PALSAR and MOD09A1 and Agricultural Statistics showed consistent results with R2 = 0.81 and R2 = 0.93, respectively. The estimated and observed DOYs showed RMSEs = 9.21, 9.29, and 9.69 days for the Start of Season (SOS), heading stage, and End of Season (EOS), respectively. Using the method, one can estimate the relative damage provided available information on the flood depth and velocity. The results of the study may support the efforts to reduce the potential damages from flooding in irrigated rice fields.

  12. Improving yield and water productivity of maize grown under deficit-irrigated in dry area conditions

    Directory of Open Access Journals (Sweden)

    Mohamed H. Abd el-wahed

    2015-10-01

    Full Text Available Scarcity of water is the most severe constraint for development of maize in arid and semi-arid areas. Based on the actual crop need, the irrigation management has to be improved so that the water supply to the crop can be reduced while still achieving high yield. Therefore, the current study has been organized to evaluate the effects of deficit sprinkler irrigation (DSI and farmyard manure (FYM on Grain yield (GY and crop water productivity (CWP of corn, a 2-year experiment was conducted in arid region of Libya. The DSI treatments were (I100 = 100%, I85 = 85% or I70 = 70% of the crop evapotranspiration. FYM treatments were (0, 10 ton ha−1 spread either on the soil surface, incorporated with surface or subsurface layer (FYM10s, FYM10m or FYM10ss, respectively and 20 ton ha−1 spread as before (FYM20s, FYM20m or FYM20ss, respectively. Results indicated that the highest values of grain yield (GY were obtained from I100 treatment, while the lowest were observed in I70. FYM20ss enhanced GY than other FYM treatments in both seasons. The highest GY and CWP were recorded with I100 and received FYM20ss. It could be considered as a suitable under arid environmental conditions and similar regions, the treatment (I100 × FYM20ss is the most suitable for producing high GY and CWP. Under limited irrigation water, application of (I85 ×FYM20ss treatment was found to be favorable to save 15% of the applied irrigation water, at the time in which produced the same GY.

  13. Short communication. Effect of deficit irrigation on curly lettuce grown under semiarid conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kuslu, Y.; Dursun, A.; Sahin, U.; Kiziloglu, F. M.; Turan, M.

    2008-07-01

    Field experiments were conducted to characterize the effects of deficit irrigation on curly lettuce (Lactuca sativa var. Crispa cv. Bohemia) evapotranspiration, water use efficiency, marketable yield, yield components and mineral contents. The experiments were performed under semiarid climatic conditions in Erzurum province (east of Turkey) in the summer periods of 2005 and 2006. Irrigation water levels were selected to be 100% of usable soil water in full irrigation treatment (control) (T-100) and 80%, 60%, 40% and 20% of usable soil water in deficit irrigation treatments (T-80, T-60, T-40 and T- 20, respectively). Average seasonal evapotranspiration was 232 mm in T-100 and 121 mm in T-20. Average marketable yield was 39.49 Mg ha{sup -}1 in T-100 and 14.57 Mg ha{sup -}1 in T-20. A linear relationship (y=0.23x-13.97; R{sup 2}0.94) was found between seasonal evapotranspiration (x) and marketable plant yield (y). According to the regression equation, the yield response factor (k{sub y}) was found to be 1.39, and the coefficient of determination 0.91. Average water use efficiency was 168.88 kg ha{sup -}1 mm{sup -}1 in T-100 and 117.39 kg ha{sup -}1 mm{sup -}1 in T-20. The lowest plant length, width, steam diameter, leaf number, macro and micro element content values were obtained for T-20 in both years. (Author) 21 refs.

  14. Irrigation, Planting Date And Intra-Row Spacing Effects On Soybean Grown Under Dry Farming Systems

    OpenAIRE

    Ismail, A. M. A. [احمد محمد علي اسماعيل; Khalifa, F. M.

    1987-01-01

    Two soybean cultivars (Glycine maxima (L) Merr.) differing in maturity period, leaf size and stem height were sown five times at fortnight intervals during the rainy season at four intra—row spacings under supplementary irrigation at one site and under rainfed conditions at another site in the central rainlands of Sudan. Cultivars responded differently to the system of production. Sowing date and moisture availability were the main factors controlling soybean production. The late maturing cul...

  15. The strategies of local farmers' water management and the eco-hydrological effects of irrigation-drainage engineering systems in world heritage of Honghe Hani Rice Terraces

    Science.gov (United States)

    Gao, Xuan

    2017-04-01

    Terraces are built in mountainous regions to provide larger area for cultivation,in which the hydrological and geomorphological processes are impacted by local farmers' water management strategies and are modified by manmade irrigation-drainage engineering systems.The Honghe Hani Rice Terraces is a 1300a history of traditional agricultural landscape that was inscribed in the 2013 World Heritage List.The local farmers had developed systematic water management strategies and built perfect irrigation-drainage engineering systems to adapt the local rainfall pattern and rice farming activities.Through field investigation,interviews,combined with Geographic Information Systems,Remote Sensing images and Global Positioning Systems technology,the water management strategies as well as the irrigation-drainage systems and their impacts on eco-hydrological process were studied,the results indicate:Firstly,the local people created and maintained an unique woodcarving allocating management system of irrigating water over hundreds years,which aids distributing water and natural nutrition to each terrace field evenly,and regularly according to cultivation schedule.Secondly,the management of local people play an essential role in effective irrigation-drainage engineering system.A ditch leader takes charge of managing the ditch of their village,keeping ample amount of irrigation water,repairing broken parts of ditches,dealing with unfair water using issues,and so on.Meanwhile,some traditional leaders of minority also take part in.Thus, this traditional way of irrigation-drainage engineering has bringed Hani people around 1300 years of rice harvest for its eco-hydrological effects.Lastly we discuss the future of Honghe Hani Rice Terraces,the traditional cultivation pattern has been influenced by the rapid development of modern civilization,in which some related changes such as the new equipment of county roads and plastic channels and the water overusing by tourism are not totally

  16. Effect of timing of joint application of hydroquinone and dicyandiamide on nitrous oxide emission from irrigated lowland rice paddy field.

    Science.gov (United States)

    Li, Xianglan; Zhang, Guangbin; Xu, Hua; Cai, Zucong; Yagi, Kazuyuki

    2009-06-01

    A field experiment was conducted to study the effect of timing of joint application of urease inhibitor hydroquinone (HQ) and nitrification inhibitor dicyandiamide (DCD) on N(2)O emission from irrigated lowland rice paddy field. Four treatments including Treatment CK (the control with urea alone), HQ/DCD-1 (application of HQ and DCD together with fertilizer before transplanting), HQ/DCD-2 (HQ and DCD with fertilizer at tillering stage) and HQ/DCD-3 (HQ and DCD with fertilizer at panicle initiation stage) were designed and implemented separately during rice growth period. Seasonal peaks of N(2)O flux occurred during midseason drainage and significant negative correlation between N(2)O flux and water layer depth was observed (r=-0.69 to -0.75, P<0.01). Mean N(2)O flux was the highest in the control with urea alone, while joint addition of HQ and DCD with urea lowered mean N(2)O flux considerably (P<0.05). Total N(2)O emission during rice growth season in Treatment CK, HQ/DCD-1, HQ/DCD-2 and HQ/DCD-3 was 3.90, 2.98, 1.73 and 3.23kgN(2)O-N ha(-1), respectively. Application of HQ and DCD together with basal fertilizer, tillering fertilizer and panicle initiation fertilizer decreased the total N(2)O emission by 24%, 56% and 17%, respectively, while increased grain yield by 10%, 18% and 6%, respectively. Effect of application of inhibitors on N(2)O emission during the continuous period from incorporation of HQ and DCD to rice harvest was also studied, where results indicating that the highest inhibiting efficiency of inhibitors on N(2)O emission was recorded when HQ and DCD applied with fertilizer at tillering stage.

  17. Estimate of uptake and translocation of emerging organic contaminants from irrigation water concentration in lettuce grown under controlled conditions.

    Science.gov (United States)

    Hurtado, Carlos; Domínguez, Carmen; Pérez-Babace, Lorea; Cañameras, Núria; Comas, Jordi; Bayona, Josep M

    2016-03-15

    The widespread distribution of emerging organic contaminants (EOCs) in the water cycle can lead to their incorporation in irrigated crops, posing a potential risk for human consumption. To gain further insight into the processes controlling the uptake of organic microcontaminants, Batavia lettuce (Lactuca sativa) grown under controlled conditions was watered with EOCs (e.g., non-steroidal anti-inflammatories, sulfonamides, β-blockers, phenolic estrogens, anticonvulsants, stimulants, polycyclic musks, biocides) at different concentrations (0-40μgL(-1)). Linear correlations were obtained between the EOC concentrations in the roots and leaves and the watering concentrations for most of the contaminants investigated. However, large differences were found in the root concentration factors ( [Formula: see text] =0.27-733) and leaf translocation concentration factors ( [Formula: see text] =0-3) depending on the persistence of the target contaminants in the rhizosphere and the specific physicochemical properties of each one. With the obtained dataset, a simple predictive model based on a linear regression and the root bioconcentration and translocation factors can be used to estimate the concentration of the target EOCs in leaves based on the dose supplied in the irrigation water or the soil concentration. Finally, enantiomeric fractionation of racemic ibuprofen from the initial spiking mixture suggests that biodegradation mainly occurs in the rhizosphere. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Nitrogen utilization efficiency and yield response of drip-irrigated tomatoes grown in the glass house

    International Nuclear Information System (INIS)

    Elinc, F.; Deviren, A.; Oeztuerk, A.

    1996-01-01

    This greenhouse study conducted on a Mediterranean Terra Rose soil, as a single crop production, heated only for anti frost, was designed to investigate the response of drip-irrigated tomatoes (Lycopersicon esculentum Mill.) to four nitrogen levels continually applied with the irrigation stream. Water containing 0, 50, 100 or 150 mgN/l and uniformly supplied with 60 and 180 mg/l of P and K, respectively, were applied two times a week. Three adjacent plants in each plot were fertigated with N 15 labeled NH 4 S 2 O 4 (2% a.e. enrichment). For each plant the amount of water, P,K and the N 15 applied through the bottles was equivalent to that amount applied through a single dripper. These treatments were compared with banded application of NH 4 S 2 O 4 at the rate of 400 kgN/ha that was equivalent to 100 mgN/l treatment. The resulting N application totals ranged from 200 to 600 kgN/ha.The total amount of water applied was 427mm. The results obtainedshowed that the percentage fertilizer utilization by the tomatoes was the highest in 50 mgN/l (200 kgN/ha) treatment, 100 mgN/l (400 kgN/ha) treatment, was on the second row, the percentage fertilizer utilization in 150 mgN/l (600 kgN/ha) and soil applications (400 kgN/ha) were the same and were significantly lower than the other treatments. The highest yield was achieved in the 100 and 150 mgN/l (400 and 600 kgN/ha) treatments. This experiment demonstrated that the amount of N fertilizer by applying in the irrigation water is to be recommended 100 mgN/l for tomatoes to obtain high yield in production under greenhouse conditions

  19. The effect of iron plaque on uptake and translocation of norfloxacin in rice seedlings grown in paddy soil.

    Science.gov (United States)

    Yan, Dafang; Ma, Wei; Song, Xiaojing; Bao, Yanyu

    2017-03-01

    Although the role of iron plaque on rice root surface has been investigated in recent years, its effect on antibiotic uptake remains uncertain. In the study, pot experiment was conducted to investigate the effect of iron plaque on uptake and translocation of norfloxacin (adding 10 and 50 mg·kg -1 treatments) in rice seedlings grown in paddy soil. Iron plaque was induced by adding different amounts of Fe(II) in soil. The results showed that the presence of norfloxacin can decrease the amount of iron plaque induced. After rice with iron plaque induced, norfloxacin was mainly accumulated in iron plaque on root surface, followed by inside root, but its translocation from root to other rice tissues is not observed. Iron plaque played the role of a barrier for norfloxacin uptake into rice roots under high norfloxacin concentration of 50 mg·kg -1 , however not that under low concentration of 10 mg·kg -1 . And the barrier function was the most strongest with adding Fe(II) of 30 mg·kg -1 as combined action of iron plaque and rhizosphere effect. Fluorescence microscope analysis showed that norfloxacin mainly distributed in the outside of root cell, which showed its translocation as apoplastic pathway in rice. Comparing with non-rhizosphere, more norfloxacin was accumulated in rhizosphere soil. Maybe, strong root oxidization (high Eh values) induced more iron oxide formation in rhizosphere and on root surface, which led to norfloxacin's mobility towards to rhizosphere through its strong adsorption of iron oxides and then promoted its uptake by rice on root surface.

  20. Tritium dynamics in soils and plants grown under three irrigation regimes at a tritium processing facility in Canada

    International Nuclear Information System (INIS)

    Mihok, S.; Wilk, M.; Lapp, A.; St-Amant, N.; Kwamena, N.-O.A.; Clark, I.D.

    2016-01-01

    The dynamics of tritium released from nuclear facilities as tritiated water (HTO) have been studied extensively with results incorporated into regulatory assessment models. These models typically estimate organically bound tritium (OBT) for calculating public dose as OBT itself is rarely measured. Higher than expected OBT/HTO ratios in plants and soils are an emerging issue that is not well understood. To support the improvement of models, an experimental garden was set up in 2012 at a tritium processing facility in Pembroke, Ontario to characterize the circumstances under which high OBT/HTO ratios may arise. Soils and plants were sampled weekly to coincide with detailed air and stack monitoring. The design included a plot of native grass/soil, contrasted with sod and vegetables grown in barrels with commercial topsoil under natural rain and either low or high tritium irrigation water. Air monitoring indicated that the plume was present infrequently at concentrations of up to about 100 Bq/m"3 (the garden was not in a major wind sector). Mean air concentrations during the day on workdays (HTO 10.3 Bq/m"3, HT 5.8 Bq/m"3) were higher than at other times (0.7–2.6 Bq/m"3). Mean Tissue Free Water Tritium (TFWT) in plants and soils and OBT/HTO ratios were only very weakly or not at all correlated with releases on a weekly basis. TFWT was equal in soils and plants and in above and below ground parts of vegetables. OBT/HTO ratios in above ground parts of vegetables were above one when the main source of tritium was from high tritium irrigation water (1.5–1.8). Ratios were below one in below ground parts of vegetables when irrigated with high tritium water (0.4–0.6) and above one in vegetables rain-fed or irrigated with low tritium water (1.3–2.8). In contrast, OBT/HTO ratios were very high (9.0–13.5) when the source of tritium was mainly from the atmosphere. TFWT varied considerably through time as a result of SRBT's operations; OBT/HTO ratios showed no clear

  1. Flora, life form characteristics, and plan for the promotion of biodiversity in South Korea's Globally Important Agricultural Heritage System, the traditional Gudeuljang irrigated rice terraces in Cheongsando

    Institute of Scientific and Technical Information of China (English)

    Hong Chul PARK; Choong Hyeon OH

    2017-01-01

    The objectives of this study were to analyze the biodiversity of the Traditional Gudeuljang Irrigated Rice Terraces in Cheongsando,South Korea's representative GIAHS (Globally Important Agricultural Heritage System) site,with reference to position and land-use features,and to develop a plan to promote agricultural biodiversity in the region.We confirmed approximately 54,000 m2 of Gudeuljang paddy fields by an on-site survey.Of the Traditional Gudeuljang Irrigated Rice Terraces confirmed by onsite inspection,our survey showed that approximately 24,000 m2 are currently being used as paddy fields,approximately 15,000 m2 are being used as dry fields,and approximately 14,000 m2 are fallow.In terms of other non-agricultural land use,there was grassland,including graveyards;artificial arboreal land,such as orchards,rivers and wetlands,and man-made facilities,such as roads and residences.We also confirmed that the Traditional Gudeuljang Irrigated Rice Terraces had higher plant species diversity than conventional terraced rice paddies,and there was a difference in life form characteristics between the two types.Although the superficial topsoil structure is the same for the Traditional Gudeuljang Irrigated Rice Terraces (TGIRTs) and conventional terraced rice paddies,it is thought that the differences in the subsurface structure of the TGIRTs contribute greatly to species and habitat diversity.However,the TGIRTs in Cheongsando are facing degeneration,due to damage and reduction in agricultural activity.The main cause is the reduction in the number of farming households due to an aging population in Cheongsando.In order to address this problem,we proposed a management plan,related to fallow paddy fields in South Korea,to initiate voluntary activities in the TGIRTs.

  2. Assessment of toxic metals in wheat crops grown on selected soils, irrigated by different water sources

    Directory of Open Access Journals (Sweden)

    Zeid A. Al-Othman

    2016-11-01

    Full Text Available We describe a comparative study of the concentration of different metals (e.g., Cd, Pb, As, Ni, Cu, Zn, Mn, and Cr in various parts of wheat plants (e.g., roots, stem, leaves and seeds collected at several locations in Khyber Pukhtoon Khaw, Pakistan. The wheat crop in these areas was irrigated using different irrigation sources, including rain, tube well, river, and canal. In wheat samples, the concentration of metals was analyzed using an atomic absorption spectrophotometer. Among the various parts of the plant, the roots had the highest levels of heavy metals, followed by the vegetative parts. By comparison, the seeds and grains had the lowest levels of heavy metals. The levels of heavy metals in all of the studied areas were not significantly localized to any particular area. The general order for the accumulation of studied metals in wheat was found to be Mn > Zn > Cu > Ni > Cr > As > Pb > Cd.

  3. Morphological Variation of Six Pigmented Rice Local Varieties Grown in Organic Rice Field in Sengguruh Village, Kepanjen District, Malang Regency

    Directory of Open Access Journals (Sweden)

    Shinta

    2014-05-01

    Full Text Available Indonesia is the third richest country for pigmented rice source such as Wojalaka black rice of East Nusa Tenggara (NTT, Manggarai of NTT, Toraja of South Sulawesi, Cempo Ireng of Central Java and red rice of Aek Sibundong (leading variety and Baubau of Southeast Sulawesi. However, the morphological character of pigmented rice in Indonesia is less reported. The objective of research was to compare the morphological variation of root, stem, leaf, panicle, floret and the colour of milk mature grain and mature grain by observing the vegetative and generative parts of six local rice varieties. Research had been conducted from February 2012 to February 2014 in Sengguruh Village, Kepanjen District, Malang Regency. This study type was quasi-experiment with eleven replications. Group Random Design was used. The observation was given upon vegetative, reproductive and maturity phases as groups. Independent variables in this study were six rice varieties, while the dependent variable was morphological variation (root, stem, leaf, panicle, floret, milk mature grain and mature grain. The analysis of multivariate data in cluster and bip lot was carried out with PAST. The result of the study indicated that there was morphological difference on stem, leaf, panicle, floret, milk mature grain and mature grain. The colour of the stem in Aek Sibundong variety was purple, while that of other varieties was green. Toraja and Manggarai varieties had the highest height with 163-168 cm, followed by Cempo Ireng with 139 cm, Wojalaka and Baubau with 110-112 cm. Aek Sibundong Variety had the lowest height with 99 cm. Aek Sibundong and Wojalaka varieties had 6-7 internodes which were the greatest number of internode, while other varieties only had 4-5 internodes. Some varieties, such as Aek Sibundong, Wojalaka and Baubau had short and small leaf. The leaflet angle of Aek Sibundong and Baubau were 14o and it might be said as upright, while that of Wojalaka was 43o or moderate

  4. Effect of different irrigated conditions on some morphological traits of wheat genotypes grown in Saudi Arabia

    International Nuclear Information System (INIS)

    Albokari, A. A.; Majeed, A.; Almuwalid, A.

    2016-01-01

    The Kingdom of Saudi Arabia being one of the driest countries globally needs drought tolerant wheat varieties. Breeding studies were conducted to determine the effects of different irrigation levels on some morphological traits of 4 wheat varieties. A pot-house experiment was conducted in split plot design using two different irrigations (well-watered and partial moisture stress) levels. Presently, the study was laid on different traits viz. plant height (cm), tiller number/plant, number of leaves/plant, leaf length (cm), flowering time (days), maturity time (days), 1000-grain weight (g) and grain yield/plant (g). The mean square from pooled analysis of variance revealed that the genotypes, treatments and genotype x treatment interaction were highly significant (p>0.05) for the traits leaf length, plant height, maturity time,1000-grain weight, grain yield per plot; however, number of leaves, number of tillers/plant, flowering time and 1000-grain weight showed non-significant difference. Similarly, genotype x reading interaction was also highly significant (p>0.05) leaf length, number of tillers per plant and plant height. The varieties Nukrat Zahran, Samrra Najran and Halba Najran and showed better performance for grain yield and maximum 1000-grain weight under both environments. Plant height showed highly significant positive correlation with number of leaves per plant and number of tillers per plant. At partial stress, 1000-grain weight showed highly significant (p>0.01) correlation (r=0.8608) with grain yield and maturity time (r=0.9948). The knowledge obtained through this research will be helpful while selection of best varieties with better tolerance to environmental stresses. (author)

  5. PERFORMANCE OF PROMISING HYBRID RICE IN TWO DIFFERENT ELEVATIONS OF IRRIGATED LOWLAND IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Yuni Widyastuti

    2015-06-01

    Full Text Available The hybrid rice program has been established since early 1990’s at the Indonesia Center for Rice Research (ICRR. Twenty-four experimental hybrid rice varieties which have been developed were tested in lowland rice fields in Sukamandi (West Java and Batang (Central Java during the dry season and the rainy season of 2012. Randomized complete block design (RCBD with three replications was used in each location. The results showed that grains yields were affected by locations, seasons, and genotypes. The genotypes x locations x seasons interaction effect was significant; therefore, the best hybrid was different for each location and season. A7/PK36 hybrid has the best performance in Batang during the dry season, while A7/PK40 and A7/PK32 are the best hybrids in the rainy season. In Sukamandi, nine hybrids were identified as better yielder than that of the check cultivar in the dry season, but not so in the rainy season. Using the correlation and path analysis, we found that the number of panicles per hill and the number of filled grains per panicle could be used as selection criteria for yield in hybrid rice.

  6. Spider assemblages associated with different crop stages of irrigated rice agroecosystems from eastern Uruguay.

    Science.gov (United States)

    Bao, Leticia; Ginella, Juaquín; Cadenazzi, Mónica; Castiglioni, Enrique A; Martínez, Sebastián; Casales, Luis; Caraballo, María P; Laborda, Álvaro; Simo, Miguel

    2018-01-01

    The rice crop and associated ecosystems constitute a rich mosaic of habitats that preserve a rich biological diversity. Spiders are an abundant and successful group of natural predators that are considered efficient in the biocontrol of the major insect pests in agroecosystems. Spider diversity in different stages of the rice crop growth from eastern Uruguay was analysed. Field study was developed on six rice farms with rotation system with pasture, installed during intercropping stage as cover crop. Six rice crops distributed in three locations were sampled with pitfall and entomological vaccum suction machine. Sixteen families, representing six guilds, were collected. Lycosidae, Linyphiidae, Anyphaenidae and Tetragnathidae were the most abundant families (26%, 25%, 20% and 12%, respectively) and comprised more than 80% of total abundance. Other hunters (29%), sheet web weavers (25%) and ground hunters (24%) were the most abundant guilds. Species composition along different crop stages was significantly different according to the ANOSIM test. The results showed higher spider abundance and diversity along the crop and intercrop stages. This study represents the first contribution to the knowledge of spider diversity associated with rice agroecosystem in the country.

  7. EFFECT OF COVER CROPS ON SOIL ATTRIBUTES, PLANT NUTRITION, AND IRRIGATED TROPICAL RICE YIELD

    Directory of Open Access Journals (Sweden)

    ANDRE FROES DE BORJA REIS

    2017-01-01

    Full Text Available In flood plains, cover crops are able to alter soil properties and significantly affect rice nutrition and yield. The aims of this study were to determine soil properties, plant nutrition, and yield of tropical rice cultivated on flood plains after cover crop cultivation with conventional tillage (CT and no-tillage system (NTS at low and high nitrogen (N fertilization levels. The experimental design was a randomized block in a split-split-plot scheme with four replications. In the main plots were cover crops sunhemp (Crotalaria juncea and C. spectabilis, velvet bean (Mucuna aterrima, jackbean (Canavalia ensiformis, pigeon pea (Cajanus cajan, Japanese radish (Raphanus sativus, cowpea (Vigna unguiculata and a fallow field. In the subplots were the tillage systems (CT or NTS. The nitrogen fertilization levels in the sub-subplots were (10 kg N ha-1 and 45 kg N ha-1. All cover crops except Japanese radish significantly increased mineral soil nitrogen and nitrate concentrations. Sunhemp, velvet bean, and cowpea significantly increased soil ammonium content. The NTS provides higher mineral nitrogen and ammonium content than that by CT. Overall, cover crops provided higher levels of nutrients to rice plants in NTS than in CT. Cover crops provide greater yield than fallow treatments. Rice yield was higher in NTS than in CT, and greater at a higher rather than lower nitrogen fertilization level.

  8. On the irrigation requirements of cottonwood (Populus fremontii and Populus deltoides var. wislizenii) and willow (Salix gooddingii) grown in a desert environment

    Science.gov (United States)

    Hartwell, S.; Morino, K.; Nagler, P.L.; Glenn, E.P.

    2010-01-01

    Native tree plots have been established in river irrigation districts in the western U.S. to provide habitat for threatened and endangered birds. Information is needed on the effective irrigation requirements of the target species. Cottonwood (Populus spp.) and willow (Salix gooddingii) trees were grown for seven years in an outdoor plot in a desert environment in Tucson, Arizona. Plants were allowed to achieve a nearly complete canopy cover over the first four years, then were subjected to three daily summer irrigation schedules of 6.20??mm??d-1; 8.26??mm??d-1 and 15.7??mm??d-1. The lowest irrigation rate was sufficient to maintain growth and high leaf area index for cottonwoods over three years, while willows suffered considerable die-back on this rate in years six and seven. These irrigation rates were applied April 15-September 15, but only 0.88??mm??d-1 was applied during the dormant period of the year. Expressed as a fraction of reference crop evapotranspiration (ETo), recommended annual water applications plus precipitation (and including some deep drainage) were 0.83 ETo for cottonwood and 1.01 ETo for willow. Current practices tend to over-irrigate restoration plots, and this study can provide guidelines for more efficient water use. ?? 2010 Elsevier Ltd.

  9. Future Irrigation Requirement of Rice Under Irrigated Area - Uncertainty through GCMs and Crop Models : A Case Study of Indo-Gangetic Plains of India

    Science.gov (United States)

    Pillai, S. N.; Singh, H.; Ruane, A. C.; Boote, K. G.; Porter, C.; Rosenzweig, C.; Panwar, A. S.

    2017-12-01

    Indo-Gangetic Plains (IGP), the food basket of South Asia, characterised by predominantly cereal-based farming systems where livestock is an integral part of farm economy. Climate change is projected to have significant effects on agriculture production and hence on food and livelihood security because more than 90 per cent farmers fall under small and marginal category. The rising temperatures and uncertainties in rainfall associated with global warming may have serious direct and indirect impacts on crop production. A loss of 10-40% crop production is predicted in different crops in India by the end of this century by different researchers. Cereal crops (mainly rice and wheat) are crucial to ensuring the food security in the region, but sustaining their productivity has become a major challenge due to climate variability and uncertainty. Under AgMIP Project, we have analysed the climate change impact on farm level productivity of rice at Meerut District, Uttar Pradesh using 29 GCMs under RCP4.5 and RCP8.5 during mid-century period 2041-2070. Two crop simulation models DSSAT4.6 and APSIM7.7 were used for impact study. There is lot of uncertainty in yield level by different GCMs and crop models. Under RCP4.5, APSIM showed a declining yield up to 14.5 % while DSSAT showed a declining yield level of 6.5 % only compared to the baseline (1980-2010). However, out of 29 GCMs, 15 GCMs showed negative impact and 14 showed positive impact under APSIM while it showed 21 and 8 GCMs, respectively in the case of DSSAT. DSSAT and APSIM simulated irrigation water requirement in future of the order of 645±75 mm and 730±107 mm, respectively under RCP4.5. However, the same will be of the order of 626 ± 99 mm and 749 ± 147 mm, respectively under RCP8.5. Projected irrigation water productivity showed a range of 4.87-12.15 kg ha-1 mm-1 and 6.77-12.63 kg ha-1 mm-1 through APSIM and DSSAT, respectively under RCP4.5, which stands an average of 7.81 and 8.53 kg ha-1 mm-1 during the

  10. Performance of cotton crop grown under surface irrigation and drip fertigation. I. seed cotton yield, dry matter production, and lint properties

    International Nuclear Information System (INIS)

    Janat, M.; Somi, G.

    2002-01-01

    reproductive-vegetative plant parts ratio decreased with increasing N input under drip fertigation. Water saving under drip fertigation exceeded 35% of irrigation water relative to surface irrigation of the cotton crop grown under the same conditions. (author)

  11. Dinitrogen fixation measurements in some legume crops grown under irrigated condition without bacteria inoculation using 15N

    International Nuclear Information System (INIS)

    Kurdali, F.; Sharabi, N.D.

    1991-01-01

    N 2 -fixation in some legume crops: Faba bean Vicia faba, common bean pisum sativum, lentil lens esculenta, chick pea cicer artinum and vetch vicia arvillia grown under irrigated conditions without Rhizobium inoculation was estimated using 15 N-labelled fertilizer method. Barley was used as a reference crop. Significant differences occured in N 2 -fixation capacity among legume crops at flowering and podding stages. The highest percentage of Nitrogen fixed occured in faba bean (88% of total N), while lower values were observed in the other crops: Lentil 84%, vetch 68%, common pea 67% and chick pea 57%. Moreover, amounts of N 2 -fixed were 171, 138, 100, 90 and 13 Kg. N. ha -1 respectively for faba bean, lentil, vetch, common pea and chick pea. This clearly indicates the importance of biological dinitrogen fixation in local legume crops nodulated with indigenous Rhizobium strains regarding to N-soil enrichment. Further investigations must be focused on the selection of both plant species and Rhizobium strains in order to obtain a good symbiotic system. (author). 2 figs

  12. Tritium dynamics in soils and plants grown under three irrigation regimes at a tritium processing facility in Canada.

    Science.gov (United States)

    Mihok, S; Wilk, M; Lapp, A; St-Amant, N; Kwamena, N-O A; Clark, I D

    2016-03-01

    The dynamics of tritium released from nuclear facilities as tritiated water (HTO) have been studied extensively with results incorporated into regulatory assessment models. These models typically estimate organically bound tritium (OBT) for calculating public dose as OBT itself is rarely measured. Higher than expected OBT/HTO ratios in plants and soils are an emerging issue that is not well understood. To support the improvement of models, an experimental garden was set up in 2012 at a tritium processing facility in Pembroke, Ontario to characterize the circumstances under which high OBT/HTO ratios may arise. Soils and plants were sampled weekly to coincide with detailed air and stack monitoring. The design included a plot of native grass/soil, contrasted with sod and vegetables grown in barrels with commercial topsoil under natural rain and either low or high tritium irrigation water. Air monitoring indicated that the plume was present infrequently at concentrations of up to about 100 Bq/m(3) (the garden was not in a major wind sector). Mean air concentrations during the day on workdays (HTO 10.3 Bq/m(3), HT 5.8 Bq/m(3)) were higher than at other times (0.7-2.6 Bq/m(3)). Mean Tissue Free Water Tritium (TFWT) in plants and soils and OBT/HTO ratios were only very weakly or not at all correlated with releases on a weekly basis. TFWT was equal in soils and plants and in above and below ground parts of vegetables. OBT/HTO ratios in above ground parts of vegetables were above one when the main source of tritium was from high tritium irrigation water (1.5-1.8). Ratios were below one in below ground parts of vegetables when irrigated with high tritium water (0.4-0.6) and above one in vegetables rain-fed or irrigated with low tritium water (1.3-2.8). In contrast, OBT/HTO ratios were very high (9.0-13.5) when the source of tritium was mainly from the atmosphere. TFWT varied considerably through time as a result of SRBT's operations; OBT/HTO ratios showed no clear temporal

  13. Puddling against dry plowing for lowland rice culture in Surinam : effect on soil and plant, and interactions with irrigation and nitrogen dressing

    NARCIS (Netherlands)

    Scheltema, W.

    1974-01-01

    The influence of tillage on rice grown on heavy Surinam clay soils was investigated in pot and field trials. Included were interactions with seed rate, nitrogen dressing and distribution, water management, and variety. Four procedures for tilled layer and seedbed preparation were studied

  14. Influence of chelating ligands on arsenic uptake by hydroponically grown rice seedlings (Oryza sativa L.): a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Rahman, Mohammad A.; Hasegawa, Hiroshi; Ueda, Kazumasa; Maki, Teruya [Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa (Japan); Rahman, M.M. [Department of Botany, Faculty of Biological Sciences, Jahangirnagar University, Savar, Dhaka (Bangladesh)

    2008-06-15

    Ferric (oxyhydro-)oxides (FeO{sub x}) precipitate in the rhizosphere at neutral or alkaline pH and are adsorbed on the plant root surfaces. Consequently, the higher binding affinity of arsenate to FeO{sub x} and the low iron phytoavailability of the precipitated FeO{sub x} make the phytoremediation of arsenic difficult. In the present study, the influence of chelating ligands on arsenic and iron uptake by hydroponically grown rice seedlings (Oryza sativa L.) was investigated. When chelating ligands were not treated to the growth medium, about 63 and 71% of the total arsenic and iron were distributed in the root extract (outer root surfaces) of rice, respectively. On the other hand, ethylenediaminetetraacetic acid (EDTA), ethylenediaminedisuccinic acid (EDDS) and hydroxyiminodisuccinic acid (HIDS) desorbed a significant amount of arsenic from FeO{sub x} of the outer root surfaces. Therefore, the uptake of arsenic and iron into the roots and their subsequent translocation to the shoots of the rice seedlings increased significantly. The order of increasing arsenic uptake by chelating ligands was HIDS > EDTA > EDDS. Methylglycinediacetic acid (MGDA) and iminodisuccinic acid (IDS) might not be effective in arsenic solubilization from FeO{sub x}. The results suggest that EDDS and HIDS would be a good and environmentally safe choice to accelerate arsenic phytoavailability in the phytoremediation process because of their biodegradability and would be a competent alternative to the widely used non-biodegradable and environmentally persistent EDTA. (Abstract Copyright [2008], Wiley Periodicals, Inc.)

  15. Effect of different levels of nitrogen fertilizer on yield and quality of sugar beet Beta vulgaris irrigated with saline groundwater (fertigation and surface irrigation) and grown under saline conditions

    International Nuclear Information System (INIS)

    Janat, M.

    2009-07-01

    In a field experiment Sugar beet Beta vulgaris was grown as a spring crop during the growing seasons of 2004 and 2006, in salt affected soil, previously planted with sesbania and barley (2005 and 2003) to evaluate the response of sugar beet to two irrigation methods, (drip fertigation and surface irrigation), different levels of nitrogen fertilizer and its effect on yield and quality. Different rates of nitrogen fertilizers (0, 50, 100, 150 and 200 kg N/ ha) as urea (46% N) were injected for drip irrigation or broadcasted for the surface-irrigated treatments in four equally split applications. The 15 N labelled urea was applied to sub-plots of 1.0 m 2 in each experimental unit in a manner similar to that of unlabeled urea. Irrigation scheduling was carried out using the direct method of neutron scattering technique. Sugar beet was irrigated when soil moisture in the upper 25 cm was 80% of the field capacity (FC) and such practice continued until the six leaf stage. From the latter stage until harvest, sugar beet was irrigated when soil moisture in the upper 50 cm reached 80% of the FC. The amount of irrigation water applied, electrical conductivity of the soil paste, dry matter and fresh roots yield, total nitrogen uptake and N derived from fertilizer were also determined. Furthermore, Nitrogen use as well as water use-efficiencies for dry matter and roots yield were also calculated. Results revealed that sugar beets and dry matter yield increased with increasing N input up to 100-150 kg N/ha which was indicated by the higher dry matter yield, and sugar beet yield. Sugar percentage was also increased relative to the average percentage recorded in Syria. Crop water use efficiencies, for both the drip-fertigated and surface-irrigated treatments were increased in most cases with increasing rate of nitrogen fertilizer. During the course of this study, small increases in soil salinity under both irrigation methods were observed. Higher increases in soil salinity was

  16. Integrating Water Supply Constraints into Irrigated Agricultural Simulations of California

    Science.gov (United States)

    Winter, Jonathan M.; Young, Charles A.; Mehta, Vishal K.; Ruane, Alex C.; Azarderakhsh, Marzieh; Davitt, Aaron; McDonald, Kyle; Haden, Van R.; Rosenzweig, Cynthia E.

    2017-01-01

    Simulations of irrigated croplands generally lack key interactions between water demand from plants and water supply from irrigation systems. We coupled the Water Evaluation and Planning system (WEAP) and Decision Support System for Agrotechnology Transfer (DSSAT) to link regional water supplies and management with field-level water demand and crop growth. WEAP-DSSAT was deployed and evaluated over Yolo County in California for corn, rice, and wheat. WEAP-DSSAT is able to reproduce the results of DSSAT under well-watered conditions and reasonably simulate observed mean yields, but has difficulty capturing yield interannual variability. Constraining irrigation supply to surface water alone reduces yields for all three crops during the 1987-1992 drought. Corn yields are reduced proportionally with water allocation, rice yield reductions are more binary based on sufficient water for flooding, and wheat yields are least sensitive to irrigation constraints as winter wheat is grown during the wet season.

  17. Content Of 2,4-D-14C Herbicide Residue In Water And Soil Of Irrigated Rice Field System

    International Nuclear Information System (INIS)

    Chairul, Sofnie M.; Djabir, Elida; Magdalena, Nelly

    2000-01-01

    The investigation of 2,4-D exp.-14C herbicide residue in water and soil of irrigated rice field system was carried out. Rice plant and weeds (Monochoria vaginalis Burn. F. Presl) were planted in 101 buckets using two kinds of soil condition, I.e. normal soil and 30 % above normal compact soil. After one week planting, the plants were sprayed with 1 u Ci of 2,4-D exp.-14C and 0,4 mg non labeled 2,4-D. The herbicide residue content was determined 0, 2, 4, 8 and 10 weeks after spraying with 2,4-D herbicide. The analysis was done using Combustion Biological Oxidizer merk Harvey ox-400, and counted with Liquid Scintillation Counter merk Beckman model LS-1801. The results indicates that the herbicide contents in water and soil decrease from the first spraying with herbicide until harvest herbicide Residue content in water after harvest was 0.87 x 10 exp.-6 ppm for soil normal condition, and 0.59 x 10 exp.-6 pm for the soil 30 % up normal condition, while herbicide content in soil was 1.54 x 10 exp.-6 ppm for soil normal condition and 1.48 x 10 exp.-6 ppm for soil 30 % up normal. 2,4-D herbicide residue content in rice after harvest was 0.27 x 10 exp.-6 ppm for normal soil condition and 0.25 x 10 exp.-6 ppm for the soil 30 % up normal. 2,4-D herbicide residue content in roots and leaves of weeds after harvest were respectively 0.29 x 10 exp.-6 ppm and 0.18 x 10 exp.-6 for normal soil condition, while for 30 % up normal soil were 0.25 x 10 exp.-5 ppm and 0.63 x 10 exp.-7 ppm. This result indicates that there is no effect pollution to surrounding area, because the herbicide content is still bellow the allowed detection limit, 0.05 ppm

  18. Diversity and population dynamics of pests and predators in irrigated rice fields with treated and untreated pesticide.

    Science.gov (United States)

    Rattanapun, W

    2012-01-01

    The monitoring of rice pests and their predators in pesticide untreated and treated rice fields was conducted at the southern of Thailand. Twenty-two species in 15 families and 6 orders of rice pests were sampled from untreated rice field. For treated rice field, 22 species in 14 families and 5 orders of rice pest were collected. Regardless of treatment type, dominant species and individual number of rice pest varied to physiological stage of rice. Lepidopteran pests had highest infestation during the vegetative stage of rice growth, while hemipteran pests composed of hopper species (Hemipetra: Auchenorrhyncha) and heteropteran species (Hemiptera: Heteroptera) were dominant groups during the reproductive stage and grain formation and ripening stage of rice growth. In contrast, dominant species of predator did not change throughout rice growing season. There were 35 species in 25 families and seven orders and 40 species in 29 families and seven orders of predators collected from untreated and treated rice field, respectively. Major predators of both rice fields were Micraspis discolor (Fabricius) (Coleoptera: Coccinellidae), Tetragnatha sp. (Araneae: Tetragnathidae) and Agriocnemis pygmaea Rambur (Odonata: Agrionidae). The population dynamic of predators were not related with rice pest population in both treatments. However, the fluctuation of population pattern of rice pests in the untreated treatment were more distinctly synchronized with their predators than that of the treated treatment. There were no significant differences in the total number of rice pest and predator between two treatments at vegetative and reproductive stages of rice growth. Untreated rice field had a higher population number of predator and a lower population number of rice pest than that of treated rice field during grain formation and ripening stages. These results indicated the ago-ecosystem balance in rice fields could be produced through minimal pesticide application, in order to allow

  19. Nitrogen availability effects on gas exchange measurements in field-grown maize (Zea mays L.) under irrigated Mediterranean conditions

    Energy Technology Data Exchange (ETDEWEB)

    Isla, R.; Guillén, M.; Salmerón, M.

    2016-07-01

    There are limited studies about the effect of nitrogen (N) deficiency on leaf growth, N status, and photosynthetic capacity of maize grown under field conditions in a Mediterranean climate. The objective of this work was to evaluate the effect of different levels of mineral N availability on leaf gas exchange parameters of sprinkler irrigated maize. The experiment was conducted in a conventional maize field located in the central part of the Ebro valley (Spain) during two seasons. Using a portable LICOR-6400 equipment, instantaneous measurements and light response curves to gas exchange were conducted in plots with different levels of N supply ranging from deficient (no fertilized) to over-fertilized (300 kg N/ha). In addition to gas exchange measurements, mineral soil N content, chlorophyll meter readings (CMR), leaf N content, and grain yield were measured in the different plots. Results showed that grain yield reached a plateau (14.5 Mg/ha) when the mineral N available was about 179 kg/ha. CMR were linearly and highly related to total N in ear leaves. The relationship between light-saturated leaf photosynthesis measurements and CMR was significant but very weak (R2=0.13) at V8 and V14 stages but increased later in the growing season (R2=0.52). Plants with intermediate levels of N supply (48

  20. Nitrogen availability effects on gas exchange measurements in field-grown maize (Zea mays L.) under irrigated Mediterranean conditions

    International Nuclear Information System (INIS)

    Isla, R.; Guillén, M.; Salmerón, M.

    2016-01-01

    There are limited studies about the effect of nitrogen (N) deficiency on leaf growth, N status, and photosynthetic capacity of maize grown under field conditions in a Mediterranean climate. The objective of this work was to evaluate the effect of different levels of mineral N availability on leaf gas exchange parameters of sprinkler irrigated maize. The experiment was conducted in a conventional maize field located in the central part of the Ebro valley (Spain) during two seasons. Using a portable LICOR-6400 equipment, instantaneous measurements and light response curves to gas exchange were conducted in plots with different levels of N supply ranging from deficient (no fertilized) to over-fertilized (300 kg N/ha). In addition to gas exchange measurements, mineral soil N content, chlorophyll meter readings (CMR), leaf N content, and grain yield were measured in the different plots. Results showed that grain yield reached a plateau (14.5 Mg/ha) when the mineral N available was about 179 kg/ha. CMR were linearly and highly related to total N in ear leaves. The relationship between light-saturated leaf photosynthesis measurements and CMR was significant but very weak (R2=0.13) at V8 and V14 stages but increased later in the growing season (R2=0.52). Plants with intermediate levels of N supply (48< CMR<54) tended to have slightly higher assimilation rates than plants with higher CMR readings. As the available N increased, the saturation point, the light compensation point and significant increases of dark respiration rate were observed. Under the conditions of the study, leaf N contents of 1.9% in the ear leaf were enough to maximize leaf assimilation rates with no need to over-fertilize the maize crop.

  1. Uso de efluentes da carcinicultura de águas interiores na irrigação do arroz Use of inland shrimp farm effluent for rice irrigation

    Directory of Open Access Journals (Sweden)

    Fábio Rodrigues de Miranda

    2008-12-01

    Full Text Available O trabalho objetivou avaliar a produção de arroz e as alterações químicas do solo, em resposta à irrigação com o efluente da carcinicultura de águas interiores e comparar os resultados com aqueles obtidos com a irrigação convencional, utilizando água do Rio Jaguaribe. A produção de grãos obtida com o uso do efluente da carcinicultura foi semelhante àquela obtida com o uso da água de rio, quando foi utilizada na adubação uma dose de N-P-K equivalente a 100% da dose recomendada para a cultura. O uso do efluente na irrigação proporcionou maior produção de grãos em relação à irrigação com a água de rio, quando foi utilizada uma dose de N-P-K equivalente a 75% daquela recomendada para a cultura do arroz. Após o cultivo, o solo irrigado com o efluente apresentou maiores níveis de Na+, CEes e PST em relação ao solo irrigado com a água do Rio Jaguaribe.This study aimed to evaluate rice yield and soil chemical alterations in response to inland shrimp farm effluent use for irrigation, comparing the results to conventional irrigation, using the Jaguaribe River water. Rice yield obtained with the effluent was similar to that obtained with river water irrigation, when the N-P-K dose applied was equivalent to 100% of the crop recommended dose. Effluent irrigation produced higher grain yield as compared to river water irrigation when the N-P-K dose applied was equivalent to 75% of the rice recommended dose. After the crop was harvested the soil irrigated with the effluent presented higher levels of Na+, EC and ESR, as compared to the soil irrigated with the Jaguaribe River water.

  2. Significance of the tropical fire ant Solenopsis geminata (hymenoptera: formicidae) as part of the natural enemy complex responsible for successful biological control of many tropical irrigated rice pests.

    Science.gov (United States)

    Way, M J; Heong, K L

    2009-10-01

    The tropical fire ant Solenopsis geminata (Fabricius) often nests very abundantly in the earthen banks (bunds) around irrigated rice fields in the tropics. Where some farmers habitually drain fields to the mud for about 3-4 days, the ants can quickly spread up to about 20 m into the fields where they collect food, including pest prey such as the eggs and young of the apple snail Pomacea caniculata (Lamarck) and insects such as lepidopterous larvae and hoppers, notably Nilaparvata lugens (Stäl) the brown planthopper (Bph) and green leafhoppers Nephotettix spp. Even in drained fields, the activity of S. geminata is restricted by rainfall in the wet season. The relatively few ant workers that forage characteristically into drained fields and on to the transplanted clumps of rice plants (hills) kill the normally few immigrant Bph adults but are initially slower acting than other species of the natural enemy complex. However, larger populations of Bph are fiercely attacked and effectively controlled by rapidly recruited ant workers; whereas, in the absence of the ant, the other natural enemies are inadequate. In normal circumstances, there is no ant recruitment in response to initially small populations of immigrant Bph and no evidence of incompatibility between ant foragers and other natural enemies such as spiders. However, when many ants are quickly and aggressively recruited to attack large populations of Bph, they temporarily displace some spiders from infested hills. It is concluded that, in suitable weather conditions and even when insecticides kill natural enemies within the rice field, periodic drainage that enables S. geminata to join the predator complex is valuable for ant-based control of pests such as snails and Lepidoptera, and especially against relatively large populations of Bph. Drainage practices to benefit ants are fully compatible with recent research, which shows that periodic drainage combats problems of 'yield decline' in intensively irrigated

  3. Growth Response Of Container Grown Japanese Azalea And Euonymus And Concentration Of Nitrates And Phosphates In The Runoff Water Under Different Irrigation And Fertilization

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    Matysiak Bożena

    2015-06-01

    Full Text Available In this study a growth response of two container-grown ornamentals (Euonymus japonicus ‘Ovatus Aureus’ and Rhododendron ‘Geisha Orange’ grown under different irrigation and fertilization rates was examined. The content of nitrogen (N and phosphorus (P in the plant leaves and in leachates was measured. Two levels of irrigation – standard irrigation (SI and – high irrigation rate (HI, and three control-release fertilizers (CRFs – Multicote 17-17-17, Osmocote Exact Standard 16-9-12 and Plantacote 15-10-15, applied at the rate of 1.5, 3.0 or 4.5 g·l−1, were applied. Fast-acting fertilizers were used as the control. HI adversely affected the growth and quality of Euonymus but stimulated the growth and increased quality of Rhododendron within two years of cultivation in relation to SI. There were no significant interactions between the irrigation and fertilization treatments; irrespective of water regimes, growth responses of both plant species to used fertilizers were similar. Osmocote and Plantacote at the rate of 3 g·l−1 were the most effective for the growth of Euonymus and Rhododendron plants, except of Euonymus in the second year, when 4.5 g·l−1 CRFs resulted in the best growth of plants. HI increased the amount of runoff water as well as N-NO3 and P-PO4 losses from containers during the entire growing period, irrespective of a fertilizer type. The amount of the nitrate and phosphate in leakage was higher when higher rates of CRFs were applied. Maximum nitrate concentration in leakage was the highest 14 days after the application of CRFs.

  4. Systems and rates of aerial application of fungicides in irrigated rice

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    Tânia Bayer

    Full Text Available ABSTRACT The present research studied the performance of flat-fan and hollow-cone nozzles, with application rates of 20 and 30 L ha-1, and rotary disc atomizer with application rates of 10 and 15 L ha-1. The test was conducted with a fungicide spray tank composed of Azoxystrobin + Difenoconazole, in which the density and penetration of droplets into the canopy were evaluated using a water-sensitive paper and the distribution of the active ingredients in the plant was evaluated through the chromatographic analysis. Higher application rates resulted in higher droplet density in the upper stratum of plants. In all treatments, the penetration of the droplets was 26% into the middle stratum and 23% into the lower stratum, in relation to the top of the crop, resulting in an average 25% penetration of droplets into the leaf canopy. The active ingredients were distributed in greater quantity in the upper stratum of the plant. For the same weight, the upper part of the ‘Puitá Inta CL’ rice cultivar has a leaf area 6.4 times larger than the lower part. It was concluded that higher application rate leads to higher droplet density in the upper stratum of the leaf canopy and that all systems and application rates promoted similar penetration of droplets into the canopy.

  5. Tagging microsatellite marker to a blast resistance gene in the irrigated rice cultivar Cica-8

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    Thiago Martins Pinheiro

    2012-09-01

    Full Text Available The rice cultivar Cica-8 exhibit differential reaction to several pathotypes of Magnaporthe oryzae. The objective of the present investigation was to determine the number of alleles involved in the expression of resistance to leaf blast and identify microsatellite markers linked to these alleles. A cross between cultivar Metica-1 and Cica-8 susceptible and resistant, respectively, to pathotype IB-1 (Py1049 was made to obtain F1, F2, BC1:1 and BC1:2 progenies. Greenhouse tests for leaf blast reaction showed that resistance is controlled by a monogenic dominant gene. For testing microsatellite markers, DNA of both resistant and susceptible parents and F1 and F2 populations was extracted. As expected for single dominant gene the F2 populations segregated at a ratio of 3:1. Of the 11 microsatellite markers tested, one marker RM 7102 was found to be closely linked to the resistant allele at a distance of 2.7 cM, in the cultivar Cica-8 to pathotype IB-1.

  6. Acetylcholinesterase Inhibition and in Vitro and in Vivo Antioxidant Activities of Ganoderma lucidum Grown on Germinated Brown Rice

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    Beong Ou Lim

    2013-06-01

    Full Text Available In this study, the acetylcholinesterase inhibition and in vitro and in vivo antioxidant activities of Ganoderma lucidum grown on germinated brown rice (GLBR were evaluated. In antioxidant assays in vitro, GLBR was found to have strong metal chelating activity, DPPH, ABTS, hydroxyl and superoxide radical scavenging activity. Cell-based antioxidant methods were used, including lipid peroxidation on brain homogenate and AAPH-induced erythrocyte haemolysis. In antioxidant assays in vivo, mice were administered with GLBR and this significantly enhanced the activities of antioxidant enzymes in the mice sera, livers and brains. The amount of total phenolic and flavonoid compounds were 43.14 mg GAE/g and 13.36 mg CE/g dry mass, respectively. GLBR also exhibited acetylcholinesterase inhibitory activity. In addition, HPLC analyses of GLBR extract revealed the presence of different phenolic compounds. These findings demonstrate the remarkable potential of GLBR extract as valuable source of antioxidants which exhibit interesting acetylcholinesterase inhibitory activity.

  7. Persistência dos herbicidas imazethapyr e imazapic em solo de várzea sob diferentes sistemas de manejo Persistence of the herbicides imazethapyr and imazapic in irrigated rice soil

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    A.F. Kraemer

    2009-01-01

    Full Text Available A mistura formulada dos herbicidas imazethapyr e imazapic é utilizada para controlar arroz-vermelho em cultivos de arroz irrigado. Entretanto, esses herbicidas podem persistir no solo por longos períodos, causando introxicação ao arroz suscetível cultivado em sucessão. Este trabalho teve como objetivo avaliar o efeito de diferentes manejos de solo, durante a entressafra do arroz, sobre a ação residual do imazethapyr e imazapic, em arroz não tolerante. O residual desses herbicidas causou introxicação no arroz suscetível após um ano da última aplicação dos herbicidas. A introxicação atingiu valores máximos até 25 dias após a emergência (DAE, ocorrendo redução da introxicação após esse período, até praticamente desaparecer (60 DAE. O residual do herbicida alterou o estande de plantas, o número de colmos m-2, o número de panículas m-2 e a altura de plantas, porém não afetou a produtividade de grãos do arroz. O revolvimento do solo diminuiu a atividade do herbicida na camada superficial de solo (0-3 m.The mixture of herbicides imazethapyr and imazapic is used to control red rice in irrigated rice crops. However, such herbicides might persist on the soil for a long period causing phytotoxicity on susceptible rice grown in succession. The objective of this work was to determine the effect of different soil tillage systems during the off-season on the residual phytotoxicity of imazethapyr and imazapic on non tolerant rice. Herbicide residues caused phytotoxicity on susceptible rice with the highest values being registered 25 days after emergence and decreasing after this period until almost disappearing 60 days after emergence. Herbicide residues affected plant stand, number of stems per m², number of panicles per m² and plant height, but did not affect grain yield. Soil movement decreased herbicide activity on the superficial soil layer (0-3 cm.

  8. Amino acids composition of mycelial protein of penicillium expansum grown in acid treated rice husk mineral medium

    International Nuclear Information System (INIS)

    Khan, M.Y.; Dahot, M.U.

    2012-01-01

    The aim of the present study was to analyze the amino acids composition of single cell protein of Penicillium expansum . Mycelial biomass was produced when fungus was grown in 0.6N H/sub 2/SO/sub 4/ pretreated rice husk mineral medium incorporated with 0.5% and 1% of nitrogen sources like potassium nitrate, sodium nitrate, ammonium nitrate, peptone, yeast extract, urea, corn steep liquor and ammonium sulphate. It was observed that the growth rate of Penicillium expansum increased with 0.5% sodium nitrate produces 1.390 +- 0.084g/l of mycelial biomass. In the subsequent experiment, fermentation medium was supplemented with 0.5% and 1.0% different sugars (sucrose, glucose, fructose, maltose, galactose, lactose, carboxymethyl-cellulose, starch, mannose, and molasses) at pH 6.0 for 240 hours at 35 +- 2 deg. C in a fermenter. The highest amount of mycelial biomass (5.107 +- 0.169g/l) was obtained with 1% sucrose and followed by 4.953 +- 0.17g/l, 4.808 +- 0.14g/l and 4.844 +- 0.10g/l mycelial biomass using glucose, maltose and galactose, respectively. The mycelial biomass of Penicillium expansum contains essential and non essential amino acids like phospho-serine, serine, valine, aspartic acid, threonine, glutamic acid, glycine, isoleucine, leucine, phenylalanine, alo-lysine, halo-lysine, lysine and arginine. The glutamic acid (3355.0 +- 19.798 mu mol/g mycelia) and proline (785.0 +- 9.899 mu mol/g mycelia) were found in higher concentration than other amino acids produced by Penicillium expansum grown on rice husk supplemented with lactose. (author)

  9. The Assessment of Irrigated Land Salinization in the Aral Sea Region

    Science.gov (United States)

    Karlykhanov, Orazkhan K.; Toktaganova, Gulzhaz B.

    2016-01-01

    Agriculture is one of the main industries of Kazakhstan, especially in the Kyzylorda Region. Before the reforms, agriculture in this region was better developed than the manufacturing industry; this is no longer the case. The main crop grown on the irrigated land of the region is rice. Inefficient distribution of cultivated areas, their excessive…

  10. Biomphalaria species distribution and its effect on human Schistosoma mansoni infection in an irrigated area used for rice cultivation in northeast Brazil

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    Delmany Moitinho Barboza

    2012-09-01

    Full Text Available The role of irrigated areas for the spread of schistosomiasis is of worldwide concern. The aim of the present study was to investigate the spatial distribution of the intermediate snail host Biomphalaria in an area highly endemic for schistosomiasis due to Schistosoma mansoni, evaluating the relationship between irrigation and types of natural water sources on one hand, and the influence of place and time of water exposure on the intensity of human infection on the other. A geographical information system (GIS was used to map the distribution of the intermediate snail hosts in Ilha das Flores, Sergipe, Brazil, combined with a clinical/epidemiological survey. We observed a direct correlation between the intensity of human infection with S. mansoni and irrigation projects. Malacological studies to identify snail species and infection rates showed that B. glabrata is the main species responsible for human schistosomiasis in the municipality, but that B. straminea also plays a role. Our results provide evidence for a competitive selection between the two snail species in rice fields with a predominance of B. glabrata in irrigation systems and B. straminea in natural water sources.

  11. Influence of iron plaque on uptake and accumulation of Cd by rice (Oryza sativa L.) seedlings grown in soil.

    Science.gov (United States)

    Liu, Houjun; Zhang, Junling; Christie, Peter; Zhang, Fusuo

    2008-05-15

    Iron plaque is ubiquitously formed on the root surfaces of rice. However, little is known about the role of iron plaque in Cd movement from soil to the plant aboveground parts. A pot experiment was conducted to investigate the influence of iron plaque in Cd uptake and accumulation by rice seedlings in soil. Rice seedlings were pre-cultivated in solution culture for 16 days. Two seedlings were transplanted in a nylon bag containing no substrate but surrounded by soil amended with Fe and Cd combined at rates of 0, 1, or 2 g Fe kg(-1) and 0, 2.0, or 10 mg Cd kg(-1) soil. Fe was added to induce different amounts of iron plaque, and Cd to simulate Cd-polluted soils. Plants were grown for a further 43 days and then harvested. The length of the longest leaf and SPAD values of the newly mature leaves were measured during plant growth. Fe and Cd concentrations were determined in dithionite-citrate-bicarbonate (DCB) soil extracts and in plant roots and shoots. Shoot and root dry weights were significantly affected by Fe supply level but not by added Cd. Root dry weight declined with increasing Fe supply but shoot dry weight decreased at 2 g Fe kg(-1) and increased at 1 g Fe kg(-1) (except at 2 mg Cd kg(-1)). The length of the longest leaf and SPAD values of the newly mature leaves were significantly affected by plant growth stage and added Fe and Cd. Fe tended to diminish the negative effect of Cd on these two parameters. Cd concentrations in DCB extracts increased with increasing Cd and Fe supply. In contrast, external Fe supply markedly reduced shoot and root Cd concentrations and there was generally no significant difference between the two Fe supply levels. Shoot and root Cd concentrations increased with increasing Cd addition. Root Cd concentrations were negatively correlated with root Fe concentrations. The proportion of Cd in DCB extracts was significantly lower than in roots or shoots. The results indicate that enhanced Fe uptake by plants can diminish the negative

  12. Effectiveness of Ammonium-Nitrogen and Nitrate-Nitrogen in Irrigation Water in Paddy Rice without Topdressed Nitrogen at the Panicle Formation Stage

    OpenAIRE

    池田, 元輝; 渡辺, 孝賢; Ikeda, Motoki; Watanabe, Takayasu

    2002-01-01

    A pot experiment was conducted to evaluate the efficiency of ammonium- and nitrate- nitrogen contained in irrigation water during the reproductive growth period of paddy rice (Oryza sativa L. cv. Hinohikari) that did not receive topdressed nitrogen at the panicle formation stage. lrrigation of water containing a low level of nitrogen (7mgNL^-1) did not increase yields so much compared to topdressed nitrogen. lrrigation of water containing a high level of nitrogen (14mgNL^-1) caused substantia...

  13. Silicon accumulation and distribution in petunia and sunflower grown in a rice hull-amended substrate

    Science.gov (United States)

    Silicon (Si) is a plant beneficial element associated with mitigation of abiotic and biotic stresses. Most greenhouse-grown ornamentals are considered low Si accumulators based on foliar Si concentration. However, Si accumulates in all tissues, and there is little published data on the distributio...

  14. Magnitude differences in agronomic, chemical, nutritional, and structural features among different varieties of forage corn grown on dry land and irrigated land.

    Science.gov (United States)

    Xin, Hangshu; Abeysekara, Samen; Zhang, Xuewei; Yu, Peiqiang

    2015-03-11

    In this study, eight varieties of corn forage grown in semiarid western Canada (including Pioneer P2501, Pioneer P39m26, Pioneer P7443, Hyland HL3085, Hyland HLBaxxos, Hyland HLR219, Hyland HLSR22, and Pickseed Silex BT) were selected to explore the effect of irrigation implementation in comparison with nonirrigation on (1) agronomic characteristics, (2) basic chemical profiles explored by using a near-infrared reflectance (NIR) system, and (3) protein and carbohydrate internal structural parameters revealed by using an attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) system. Also, principal component analysis (PCA) was performed on spectroscopic data for clarification of differences in molecular structural makeup among the varieties. The results showed that irrigation treatment significantly increased (P forages. Significant interactions of irrigation treatment and corn variety were observed on most agronomic characteristics (DM yield, T/ha, days to tasseling, days to silking) and crude fiber (CF) and ether extract (EE) contents as well as some spectral data such as cellulosic compounds (CELC) peak intensity, peak ratios of CHO third peak to CELC, α-helix to β-sheet, and CHO third peak to amide I. Additionally, the spectral ratios of chemical functional groups that related to structural and nonstructural carbohydrates and protein polymers in forages did not remain constant over corn varieties cultivated with and without water treatment. Moreover, different cultivars had different growth, structure, and nutrition performances in this study. Although significant differences could be found in peak intensities, PCA results indicated some structural similarities existed between two treated corn forages with the exception of HL3085 and HLBaxxos. In conclusion, irrigation and corn variety had interaction effects on agronomic, chemical, nutritional, and structural features. Further study on the optimum level of irrigation for corn forage

  15. Arsenic accumulation in rice: Consequences of rice genotypes and management practices to reduce human health risk.

    Science.gov (United States)

    Islam, Shofiqul; Rahman, Mohammad Mahmudur; Islam, M R; Naidu, Ravi

    2016-11-01

    Rice is an essential staple food and feeds over half of the world's population. Consumption of rice has increased from limited intake in Western countries some 50years ago to major dietary intake now. Rice consumption represents a major route for inorganic arsenic (As) exposure in many countries, especially for people with a large proportion of rice in their daily diet as much as 60%. Rice plants are more efficient in assimilating As into its grains than other cereal crops and the accumulation may also adversely affect the quality of rice and their nutrition. Rice is generally grown as a lowland crop in flooded soils under reducing conditions. Under these conditions the bioavailability of As is greatly enhanced leading to excessive As bioaccumulation compared to that under oxidizing upland conditions. Inorganic As species are carcinogenic to humans and even at low levels in the diet pose a considerable risk to humans. There is a substantial genetic variation among the rice genotypes in grain-As accumulation as well as speciation. Identifying the extent of genetic variation in grain-As concentration and speciation of As compounds are crucial to determining the rice varieties which accumulate low inorganic As. Varietal selection, irrigation water management, use of fertilizer and soil amendments, cooking practices etc. play a vital role in reducing As exposure from rice grains. In the meantime assessing the bioavailability of As from rice is crucial to understanding human health exposure and reducing the risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Variable radiation use efficiency in rice cultures grown at different locations

    International Nuclear Information System (INIS)

    Raghuveera Rao, P.; Sailaja, B.; Desiraju, Subrahmanyam; Nageswara Rao, D.; Voleti, S.R.; Satyanarayana Reddy, P.; Sudarsana Rao, G.V.

    2012-01-01

    Variation in radiation use efficiency (RUE) amongst 81 rice cultures was assessed at Hyderabad, Maruteru and Pattambi locations. The RUE was computed for each culture at panicle initiation stage (RUE p i) and at physiological maturity (RUE m ) for each location. RUE p i and RUE m differed significantly amongst cultures and also between locations. The interaction between location and cultures was also found to be highly significant. The mean RUE p i for all the cultures was 1.08, 0.56 and 1.22 g MJ -1 , respectively, for HYD, MTU and PTB. The average RUE m estimated was 0.37, 0.60 and 0.93, respectively, for HYD, MTU and PTB. Out of the 81 rice cultures, very few entries consistently showed high RUE at all the three locations and at both the stages. The cultures lET 21023 and lET 20986 recorded higher, though not the highest, RUE, at panicle initiation and maturity stages at all the three locations and produced TDM and grain yield higher than the mean TDM and grain yield for all the test cultures. (author)

  17. Nitrogen Metabolism in Adaptation of Photosynthesis to Water Stress in Rice Grown under Different Nitrogen Levels

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    Chu Zhong

    2017-06-01

    Full Text Available To investigate the role of nitrogen (N metabolism in the adaptation of photosynthesis to water stress in rice, a hydroponic experiment supplying with low N (0.72 mM, moderate N (2.86 mM, and high N (7.15 mM followed by 150 g⋅L-1 PEG-6000 induced water stress was conducted in a rainout shelter. Water stress induced stomatal limitation to photosynthesis at low N, but no significant effect was observed at moderate and high N. Non-photochemical quenching was higher at moderate and high N. In contrast, relative excessive energy at PSII level (EXC was declined with increasing N level. Malondialdehyde and hydrogen peroxide (H2O2 contents were in parallel with EXC. Water stress decreased catalase and ascorbate peroxidase activities at low N, resulting in increased H2O2 content and severer membrane lipid peroxidation; whereas the activities of antioxidative enzymes were increased at high N. In accordance with photosynthetic rate and antioxidative enzymes, water stress decreased the activities of key enzymes involving in N metabolism such as glutamate synthase and glutamate dehydrogenase, and photorespiratory key enzyme glycolate oxidase at low N. Concurrently, water stress increased nitrate content significantly at low N, but decreased nitrate content at moderate and high N. Contrary to nitrate, water stress increased proline content at moderate and high N. Our results suggest that N metabolism appears to be associated with the tolerance of photosynthesis to water stress in rice via affecting CO2 diffusion, antioxidant capacity, and osmotic adjustment.

  18. Phenolic compounds and saponins in quinoa samples (Chenopodium quinoa Willd.) grown under different saline and nonsaline irrigation regimens.

    Science.gov (United States)

    Gómez-Caravaca, Ana María; Iafelice, Giovanna; Lavini, Antonella; Pulvento, Cataldo; Caboni, Maria Fiorenza; Marconi, Emanuele

    2012-05-09

    Quinoa is a pseudocereal from South America that has received increased interest around the world because it is a good source of different nutrients and rich in antioxidant compounds. Thus, this study has focused on the effects of different agronomic variables, such as irrigation and salinity, on the phenolic and saponin profiles of quinoa. It was observed that irrigation with 25% of full water restitution, with and without the addition of salt, was associated with increases in free phenolic compounds of 23.16 and 26.27%, respectively. In contrast, bound phenolic compounds were not affected by environmental stresses. Saponins decreased if samples were exposed to drought and saline regimens. In situations of severe water deficit, the saponins content decreased 45%, and 50% when a salt stress was added. The results suggest that irrigation and salinity may regulate the production of bioactive compounds in quinoa, influencing its nutritional and industrial values.

  19. Increasing CO2 differentially affects essential and non-essential amino acid concentration of rice grains grown in cadmium-contaminated soils.

    Science.gov (United States)

    Wu, Huibin; Song, Zhengguo; Wang, Xiao; Liu, Zhongqi; Tang, Shirong

    2016-09-01

    Environmental pollution by both ambient CO2 and heavy metals has been steadily increasing, but we do not know how fluctuating CO2 concentrations influence plant nutrients under high Cd pollution, especially in crops. Here, we studied the effects of elevated CO2 and Cd accumulation on proteins and amino acids in rice under Cd stress. In this pot experiment, we analyzed the amino-acid profile of 20 rice cultivars that accumulate Cd differently; the plants were grown in Cd-containing soils under ambient conditions and elevated CO2 levels. We found that although Cd concentrations appeared to be higher in most cultivars under elevated CO2 than under ambient CO2, the effect was significant only in seven cultivars. Combined exposure to Cd and elevated CO2 strongly decreased rice protein and amino acid profiles, including essential and non-essential amino acids. Under elevated CO2, the ratios of specific amino acids were either higher or lower than the optimal ratios provided by FAO/WHO, suggesting that CO2 may flatten the overall amino-acid profile, leading to an excess in some amino acids and deficiencies in others when the rice is consumed. Thus, Cd-tainted rice limits the concentration of essential amino acids in rice-based diets, and the combination with elevated CO2 further exacerbates the problem. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Yield, Quality and Water Consumption of Stevia rebaudiana Bertoni Grown under Different Irrigation Regimes in Southern Italy

    Directory of Open Access Journals (Sweden)

    Antonella Lavini

    2008-06-01

    Full Text Available Stevia rebaudiana Bertoni is a herbaceous perennial plant originating in the north-east of Paraguay. Its leaves contain low-calorie sweetening agents that can be used as a natural alternative to artificial sweeteners. The leaves are consumed in special human diets and for the treatment of various diseases. The aim of the present work is to study water consumption, yield potential and quality characteristics of this species under different irrigation levels in southern Italy. The field work was carried out in 2006-2007. Irrigation treatments consisted of a control (T100, irrigated with 100% restitution of water consumption and two treatments that received a water depth of 33% (T33 and 66% (T66 of treatment T100. Watering volume was estimated to replenish the soil profile to field capacity for a depth of 0.40 m. The crop was harvested twice a year, and agronomic performance as well as the major cation and glycoside contents (stevioside and rebaudioside A were evaluated. Overall, the crop coefficients were similar between the two years, although in each year the second growing period showed higher values due to the higher evaporative demand of this period. Interactions of years with irrigation treatments and harvest time were not significant either for yield or yield components. In both cuts the T100 treatments achieved 40% higher leaf dry yield than T33, while T66 showed intermediate values. The harvest index and water use efficiency showed no differences between the two cuts for the same treatments, while the values of both indices decreased with the increase in irrigation regime. Stevioside, rebaudioside A and cation content in the leaves were unaffected by irrigation regime. In order to develop the field cultivation of this species, field experiments are required to prepare a cultivation protocol as well as a genetic improvement program to develop varieties that better respond to the local environment.

  1. Yield, Quality and Water Consumption of Stevia rebaudiana Bertoni Grown under Different Irrigation Regimes in Southern Italy

    Directory of Open Access Journals (Sweden)

    Riccardo d’Andria

    2011-02-01

    Full Text Available Stevia rebaudiana Bertoni is a herbaceous perennial plant originating in the north-east of Paraguay. Its leaves contain low-calorie sweetening agents that can be used as a natural alternative to artificial sweeteners. The leaves are consumed in special human diets and for the treatment of various diseases. The aim of the present work is to study water consumption, yield potential and quality characteristics of this species under different irrigation levels in southern Italy. The field work was carried out in 2006-2007. Irrigation treatments consisted of a control (T100, irrigated with 100% restitution of water consumption and two treatments that received a water depth of 33% (T33 and 66% (T66 of treatment T100. Watering volume was estimated to replenish the soil profile to field capacity for a depth of 0.40 m. The crop was harvested twice a year, and agronomic performance as well as the major cation and glycoside contents (stevioside and rebaudioside A were evaluated. Overall, the crop coefficients were similar between the two years, although in each year the second growing period showed higher values due to the higher evaporative demand of this period. Interactions of years with irrigation treatments and harvest time were not significant either for yield or yield components. In both cuts the T100 treatments achieved 40% higher leaf dry yield than T33, while T66 showed intermediate values. The harvest index and water use efficiency showed no differences between the two cuts for the same treatments, while the values of both indices decreased with the increase in irrigation regime. Stevioside, rebaudioside A and cation content in the leaves were unaffected by irrigation regime. In order to develop the field cultivation of this species, field experiments are required to prepare a cultivation protocol as well as a genetic improvement program to develop varieties that better respond to the local environment.

  2. Studies on physico-chemical and cooking characteristics of rice bean varieties grown in NE region of India.

    Science.gov (United States)

    Bepary, Rejaul Hoque; Wadikar, D D; Neog, Seuji Borah; Patki, P E

    2017-03-01

    Rice bean ( Vigna umbellata ) is grown in South and Southeast Asia, and the bean has gained importance due to its nutritional strength in terms of dietary fiber, quality protein and minerals. In current study, the nutritional and functional components, cooking and thermo-gravimetric properties of eleven rice bean varieties from NE India were investigated. Results revealed that the major nutrients among the varieties ranged as follows: 54.21-60.49% carbohydrates, 15.64-21.60% protein, 1.22-2.3% fat, 5.53-6.56% crude fibre, 3.34-3.8% ash; while the functional, anti-nutritional factors and mineral were present as 1189.32-1645.8 mg gallic acid equivalent (GAE)/100 g polyphenols, 205.38-432.14 mg/100 g phytic acid, 23.14-34.12 mg/100 g oxalate, 690.7-1589.5 mg/100 g saponins, 49.90-158.17 μg/100 g hydrocyanide, 111.51-168 calcium, 5.50-10.44 zinc, 3.72-8.37 iron. Principal component analysis revealed that varieties with higher calcium, iron and ash content had lower cooking time, swelling ratio, and cooked grain hardness. It is also revealed that varieties with higher weight loss at sixth stage in thermogravimetric graph had lower carbohydrate and higher protein content. Nagadal variety had higher fat, potassium, magnesium, calcium, sodium, iron, copper and chromium content and better cooking quality as compared to the other varieties. The study revealed that Nagadal variety was superior to other varieties with respect to mineral content, cooking and thermal properties and hence have better potential in the development of value added products.

  3. Manejo de água e de fertilizante potássico na cultura de arroz irrigado Water and potassium fertilization management for irrigated rice cultivation

    Directory of Open Access Journals (Sweden)

    Alberto Baêta dos Santos

    1999-04-01

    Full Text Available O manejo da água de irrigação e as doses e épocas de aplicação de fertilizantes tornam-se aspectos de extrema importância no êxito do aproveitamento das várzeas para o cultivo de arroz (Oryza sativa L. irrigado ou este seguido de outras espécies. Com o objetivo de comparar distintas formas de manejo de água e de fertilizante potássico no comportamento do arroz irrigado, foram conduzidos experimentos por três anos consecutivos, em um Inceptissolo. Foram estudados os efeitos de manejo de água (MA1 - inundação contínua e MA2 - inundação intermitente seguida de contínua e o modo de aplicação de fertilizante potássico (K1 - na semeadura; K2 - parcelada e K3 - meia dose parcelada. O manejo de água apresentou efeito mais expressivo sobre o comportamento do arroz que o do fertilizante potássico. A inundação contínua durante todo o ciclo da cultura proporcionou maiores rendimentos de grãos, expressando maiores valores dos parâmetros produtivos, e melhorou a qualidade industrial dos grãos. Com esta irrigação, o parcelamento da adubação potássica aumentou o aproveitamento do fertilizante. Os manejos do fertilizante potássico afetaram diferentemente o comportamento da cultura do arroz nas distintas formas de manejo de água.Irrigation water levels and timing of potassium fertilization is extremely important for the use of lowlands for irrigated rice (Oryza sativa L. cultivation in crop rotation. A field experiment was conduced for three consecutive years in Inceptisol to study the effects of water management (WM1 - continuous flooding and WM2 - intermittent flooding followed continuous flooding and mode of potassium fertilizer application (K1 - at sowing; K2 - fractional application and K3 - fractional application of half levels on grain yield and yield components of irrigated rice. Water management presented expressive effect on rice performance as compared to potassium fertilization. Continuous flooding during whole

  4. Translocation kinetics of 14C-photosynthate in hybrid rice grown at different potassium levels

    International Nuclear Information System (INIS)

    Jiang Dean; Shen Yuwei; Xie Xuemin; Rao Lihua; Lu Qing

    1993-01-01

    The kinetics of translocation of 14 C-assimilate in hybrid rice plant was studied with 14 CO 2 fed to functional leaf at the tillering and filling stages. The result indicated that the relationship between percentage (V) of photosynthate exporting out of the source leaf or that of assimilate into sink, expanding young leaf or filling panicle, respectively,and time(t)after introducing 14 CO 2 into the leaf was extremely coincided with the regression equation : v = V (t + k)/K m + (t + k). At the tillering stage, fully extended top leaf could export 66% ∼ 79% of its photosynthate assimilated at different potassium levels, and both export potential and rate of 14 C-photosynthate in the fed leaf decreased under the low potassium (1 ppm K supplied), but the rate obviously increased in the superfluous potassium (80 ppm K supplied) in spite of slightly low exporting capacity. Main sink, the expanding young leaf on the top of stem could obtain 28% ∼ 59% of 14 C-assimilate at various potassium levels. Both the importation potential and rate were lowered with low potassium application while hastened by super-supplied potassium at the same development stage. At the filling stage, source, flag leaf, was able to export 83% ∼ 97% of its photosynthate and low potassium (5 ppm) application not only delayed the time of 14 C-photosynthate exportation but also diminished the export rate, whereas the rate was accelerated by superfluous potassium. Low potassium resulted in decrease both in the capacity and in the rate of assimilate importing into grain, nevertheless, high potassium caused decrease of percentage assimilate importing into grain and the increase of improving rate. Therefore, it was strategically considered that neither deficient nor superfluous potassium application was beneficial for assimilate transportation

  5. Can simulation models help design rice cultivars that are more competitive against weeds?

    NARCIS (Netherlands)

    Bastiaans, L.; Kropff, M.J.; Kempuchetty, N.; Rajan, A.; Migo, T.R.

    1997-01-01

    Differences in competitive ability between rice cultivars IR8 and Mahsuri, grown in well-fertilised irrigated conditions, were analysed by means of a mechanistic simulation model (INTERCOM) for crop-weed interaction. The analysis revealed that the greater competitive ability of Mahsuri was due

  6. Growth performance of indigenous sheep fed Sporobolus virginicus grass hay grown in saline desert lands and irrigated with high salt content ground water.

    Science.gov (United States)

    Alhadrami, G A; Al-Shorepy, S A; Yousef, A M

    2010-12-01

    Twenty-eight indigenous ewe lambs (6 months of age and 14.4 kg body weight (BW)) were used to evaluate the effect of feeding Sporobolus grass hay (SGH) as the only source of forage on growth, and feed and water intakes. The ewe lambs were randomly and equally allocated to two treatment groups (14 lambs/group). The ewe lambs in group 1 (treatment 1) received SGH, while lambs in group 2 (treatment 2) received Rhodes grass hay (RGH) as the only source of forage. Water was available at all times for both treatment groups. Sporobolus grass was irrigated with brackish water of high salt content (20,000 ppm) and grown in saline desert lands (sabkha) in the United Arab Emirates. The average daily dry matter intake was significantly (P  .05) between the two groups at all stages. From these data, we conclude that SGH can replace Rhodes hay in sheep diet without significant effect on sheep performance.

  7. Modeling root length density of field grown potatoes under different irrigation strategies and soil textures using artificial neural networks

    DEFF Research Database (Denmark)

    Ahmadi, Seyed Hamid; Sepaskhah, Ali Reza; Andersen, Mathias Neumann

    2014-01-01

    ) of the eight input variables: soil layer intervals (D), percentages of sand (Sa), silt (Si), and clay (Cl), bulk density of soil layers (Bd), weighted soil moisture deficit during the irrigation strategies period (SMD), geometric mean particle size diameter (dg), and geometric standard deviation (σg......). The results of the study showed that all the nine ANN models predicted the target RLD values satisfactorily with a correlation coefficient R2>0.98. The simplest and most complex ANN architectures were 3:2:1 and 5:5:1 consisting of D, SMD, dg, and D, Bd, SMD, σg, dg as the input variables, respectively. Low...

  8. Comparative study of endophytic and endophytic diazotrophic bacterial communities across rice landraces grown in the highlands of northern Thailand

    OpenAIRE

    Rangjaroen, C.; Rerkasem, B.; Teaumroong, N.; Sungthong, R.; Lumyong, S.

    2014-01-01

    Communities of bacterial endophytes within the rice landraces cultivated in the highlands of northern Thailand were studied using fingerprinting data of 16S rRNA and nifH genes profiling by polymerase chain reaction-denaturing gradient gel electrophoresis. The bacterial communities' richness, diversity index, evenness, and stability were varied depending on the plant tissues, stages of growth, and rice cultivars. These indices for the endophytic diazotrophic bacteria within the landrace rice ...

  9. Water and radiation use efficiencies of transplanted rice (Oryza sativa L.) at different plant densities and irrigation regimes under semi-arid environment

    International Nuclear Information System (INIS)

    Ahmad, S.; Ali, H.; Shad, S.A.; Zia-ul-Haq, M.; Ahmad, A.; Maqsood, M.; Khan, M.B.; Mehmood, S.; Hussain, A.

    2008-01-01

    Growth and yield of rice (Oryza sativa L.), in response to plant densities and irrigation (optimum to stress) were analyzed in terms of interception and utilization of photo-synthetically active radiation (PAR) and water use efficiency (WUE). The amount of PAR intercepted and cumulative evapotranspiration (ET) by each treatment was estimated from the measured leaf area index. The relationships between total dry matter grain yield and accumulated intercepted PAR and cumulative ET were linear. Yield differences among the treatments were attributed to the amount of PAR intercepted and water transpired their efficiencies of utilization or both. The fraction of intercepted radiation and WUE was significantly affected by the plant densities and various irrigation regimes, while, radiation utilization efficiency (RUE) and water use efficiency (WUE) for TDM varied from 1.15 g MJ-1 to 1.36 g MJ-1 and 22.6 kg per ha mm-1 to 24.3 kg per ha mm-1 during both the seasons

  10. Lime and Phosphate Amendment Can Significantly Reduce Uptake of Cd and Pb by Field-Grown Rice

    Directory of Open Access Journals (Sweden)

    Rongbo Xiao

    2017-03-01

    Full Text Available Agricultural soils are suffering from increasing heavy metal pollution, among which, paddy soil polluted by heavy metals is frequently reported and has elicited great public concern. In this study, we carried out field experiments on paddy soil around a Pb-Zn mine to study amelioration effects of four soil amendments on uptake of Cd and Pb by rice, and to make recommendations for paddy soil heavy metal remediation, particularly for combined pollution of Cd and Pb. The results showed that all the four treatments can significantly reduce the Cd and Pb content in the late rice grain compared with the early rice, among which, the combination amendment of lime and phosphate had the best remediation effects where rice grain Cd content was reduced by 85% and 61%, respectively, for the late rice and the early rice, and by 30% in the late rice grain for Pb. The high reduction effects under the Ca + P treatment might be attributed to increase of soil pH from 5.5 to 6.7. We also found that influence of the Ca + P treatment on rice production was insignificant, while the available Cd and Pb content in soil was reduced by 16.5% and 11.7%, respectively.

  11. Desempenho da cultura do arroz irrigado com esgotos sanitários previamente tratados Performance of upland rice irrigated with previously treated domestic sewage

    Directory of Open Access Journals (Sweden)

    José T. de Sousa

    2001-04-01

    Full Text Available Com o presente trabalho, objetiva-se avaliar o desempenho da cultura do arroz, irrigada com efluentes de esgoto sanitário provenientes de tanque séptico e de lagoa de estabilização, tomando-se como referencial comparativo a mesma cultura irrigada com água de abastecimento em solos fertilizados com adubos minerais e sem adubo mineral. No experimento foi utilizada a cultivar Diamante, originada da EMBRAPA Meio Norte, e o sistema experimental era constituído por 4 tabuleiros com 10 m² de área unitária, irrigados por inundação intermitente, procurando-se manter sempre uma média de 5 cm de lâmina líquida a cada dois dias, durante o período de 4 meses. A análise dos dados demonstra que a produtividade da cultivar Diamante, irrigada com efluente de tanque séptico, foi superior à produtividade da mesma cultivar irrigada com água de abastecimento em solo com adubação mineral. Salienta-se, ainda, que os grãos da cultivar irrigada com efluente do tanque séptico não apresentaram, em nenhum exame, indicadores de contaminação fecal.This paper evaluates the rice crop performance irrigated by domestic wastewater effluents from septic tanks and ponds in comparison to that irrigated by muncipal water supplies in soils with and without mineral fertilizers. The "Diamante" rice cultivar originated from EMBRAPA Meio Norte was used in the experiment. The experimental system consisted of 4 plots of 10 m². The plots were intermitlenttly flooded every two days during the period of four months to maintain on an average 5 cm of water depth. The analytical data show that the productivity of the cultivar "Diamante" in this system was higher than that of the same cultivar irrigated by muncipal water supplies in soils with mineral fertilizers. Also when examined, its grains did not present any traces of fecal contamination.

  12. Subsurface drainage of valley bottom irrigated rice schemes in tropical savannah : case studies of Tiefora and Moussodougou in Burkina Faso

    NARCIS (Netherlands)

    Keïta, A.

    2015-01-01

    SUMMARY

    The contrasted global population growth with the multiplication of the constraints to developing new irrigation systems puts a special challenge upon human crop production systems that needs to be taken up.

  13. Physical, milling, cooking, and pasting characteristics of different rice varieties grown in the valley of Kashmir India

    Directory of Open Access Journals (Sweden)

    Tanveer Ahmad Rather

    2016-12-01

    Full Text Available In the present study, three different rice varieties, namely frome chena (FC, safaid chena (SC, and barkat chena (BC, were evaluated for various quality aspects in terms of physical, milling, cooking, and pasting characteristics. Among the three rice varieties SC had the highest thousand kernel weight and length breadth ratio (L/B. While as, BC had the lowest thousand kernel weight and FC had lowest L/B. Bulk density was found to be highest for FC followed by SC and BC. FC had density of 769.01 kg/m3. Milling characteristic in terms of broken percentage and head rice yield showed non-significant difference between the varieties. Head rice yield was below 70% in all the three varieties. All the three varieties took similar time to cook and cooking time varied non-significantly between 23.66 and 25.83 min. L/B ratio after cooking was found to be highest for FC followed by BC and SC. Elongation ratio of rice after cooking did not varied significantly between varieties. Elongation ratio after cooking ranged from 1.60 to 1.70. Pasting profile of rice flour was determined using rapid visco analyzer. Significant difference was observed in pasting profile of studied rice varieties.

  14. Comparative study of endophytic and endophytic diazotrophic bacterial communities across rice landraces grown in the highlands of northern Thailand.

    Science.gov (United States)

    Rangjaroen, Chakrapong; Rerkasem, Benjavan; Teaumroong, Neung; Sungthong, Rungroch; Lumyong, Saisamorn

    2014-01-01

    Communities of bacterial endophytes within the rice landraces cultivated in the highlands of northern Thailand were studied using fingerprinting data of 16S rRNA and nifH genes profiling by polymerase chain reaction-denaturing gradient gel electrophoresis. The bacterial communities' richness, diversity index, evenness, and stability were varied depending on the plant tissues, stages of growth, and rice cultivars. These indices for the endophytic diazotrophic bacteria within the landrace rice Bue Wah Bo were significantly the lowest. The endophytic bacteria revealed greater diversity by cluster analysis with seven clusters compared to the endophytic diazotrophic bacteria (three clusters). Principal component analysis suggested that the endophytic bacteria showed that the community structures across the rice landraces had a higher stability than those of the endophytic diazotrophic bacteria. Uncultured bacteria were found dominantly in both bacterial communities, while higher generic varieties were observed in the endophytic diazotrophic bacterial community. These differences in bacterial communities might be influenced either by genetic variation in the rice landraces or the rice cultivation system, where the nitrogen input affects the endophytic diazotrophic bacterial community.

  15. Consumptive use of upland rice as estimated by different methods

    International Nuclear Information System (INIS)

    Chhabda, P.R.; Varade, S.B.

    1985-01-01

    The consumptive use of upland rice (Oryza sativa Linn.) grown during the wet season (kharif) as estimated by modified Penman, radiation, pan-evaporation and Hargreaves methods showed a variation from computed consumptive use estimated by the gravimetric method. The variability increased with an increase in the irrigation interval, and decreased with an increase in the level of N applied. The average variability was less in pan-evaporation method, which could reliably be used for estimating water requirement of upland rice if percolation losses are considered

  16. Assessing the impact of ambient ozone on growth and yield of a rice (Oryza sativa L.) and a wheat (Triticum aestivum L.) cultivar grown in the Yangtze Delta, China, using three rates of application of ethylenediurea (EDU)

    International Nuclear Information System (INIS)

    Wang Xiaoke; Zheng Qiwei; Yao Fangfang; Chen Zhan; Feng Zhaozhong; Manning, W.J.

    2007-01-01

    Foliar applications of ethylenediurea (abbreviated as EDU) were made at 0, 150, 300 or 450 ppm to field-grown rice and wheat in the Yangtze Delta in China. Rice and wheat responded differently to ambient ozone and EDU applications. For wheat, some growth characteristics, such as yield, seed number per plant, seed set rate and harvest index, increased significantly at 300 ppm EDU treatment, while for rice no parameters measured were statistically different regarding EDU application. The reason may be that the wheat cultivar used may be more sensitive to ozone than the rice cultivar. EDU was effective in demonstrating ozone effects on the wheat cultivar, but not on the rice cultivar. Cultivar sensitivity might be an important consideration when assessing the effects of ambient ozone on plants. - Cultivar sensitivity should be considered when using protective chemical to assess the effects of ambient ozone on plants

  17. Correlation of pasting behaviors with total phenolic compounds and starch digestibility of indigenous pigmented rice grown in upper Northern Thailand

    Directory of Open Access Journals (Sweden)

    Jirapa Ponjanta

    2016-03-01

    Full Text Available Background: Thailand has one of the most important rice genetic resources with white, light brown, brown, red, and purple rice bran colors. The latter believed to have potential for health benefits due to their phenolic content. Recently researchers have indicated that starch digestive enzymes, including salivary and pancreatic α-amylases and α-glucosidases, can be inhibited by phenolic compounds. Although pasting properties of rice flour are key determinants of quality significantly impacting the final product texture, there is no in-depth study on their correlation with phenolic compound and starch digestibility. Methods: Rice flour from twelve varieties, three from each of five bran colors (white, brown, red, and purple, were evaluated for pasting properties (RVA-3D, total phenolic compounds, amylose content, resistant starch and estimated glycemic index. Simple correlation coefficients were calculated for the relationships between pasting properties (final viscosity, breakdown, setback and pasting temperature and total phenolic compounds, resistant starch and estimated glycemic index. Results: Within each rice variety, red and purple pigmented flours had higher total phenolic compounds (TPC and more resistant starch than that of white flours. The TPC and resistant starch content of the flours ranged between 7.83- 47.3 mg/L and 2.44–10.50% respectively, and producing 60-80 of estimated glycemic index. Viscosity behavior showed that pigmented with low amylose rice had lower viscosity temperature than that of pigmented with high amylose rice flour, but higher in peak viscosity. Correlation coefficients of pasting temperature, final viscosity, break down and setback with TCP was observed to be inversely related to glycemic index. However, it was positively correlated to the resistant starch and amylose content. Conclusions: Pigmented rice flour is a better source of TPC and resistant starch which in turn provides low glycemic index. This

  18. Effect of Different Silicon Sources on Yield and Silicon Uptake of Rice Grown under Varying Phosphorus Rates

    Directory of Open Access Journals (Sweden)

    Flavia B. Agostinho

    2017-08-01

    Full Text Available A series of pot experiments were conducted to: (1 evaluate the effects of different Si sources (soil- and foliar-applied on grain yield and Si accumulation of rice supplied with varying P rates, and (2 evaluate Si absorption of rice using foliar- and soil-applied Si fertilizers. Three P rates, (0, 112, and 224 kg ha−1 combined with five Si treatments (wollastonite and slag applied at 4.5 ton ha−1 and one foliar Si solution applied at 20, 40 and 80 mg Si L−1 and a check were arranged in a randomized complete block design with four replications. The presence of P and Si in the soil created a synergistic effect on soil Al, Mn, and As (P < 0.01, but not on rice growth and P uptake. Wollastonite and slag application were most effective in raising rice Si content than foliar applied Si (P < 0.001. While there was an improvement in biomass (42% and tiller production (25% for rice receiving foliar Si, no supporting evidence was obtained in these experiments to verify leaf surface Si absorption. The application of Si-rich materials to soil still remains the most effective method for enhancing Si uptake by plants.

  19. Effect of Different Silicon Sources on Yield and Silicon Uptake of Rice Grown under Varying Phosphorus Rates.

    Science.gov (United States)

    Agostinho, Flavia B; Tubana, Brenda S; Martins, Murilo S; Datnoff, Lawrence E

    2017-08-29

    A series of pot experiments were conducted to: (1) evaluate the effects of different Si sources (soil- and foliar-applied) on grain yield and Si accumulation of rice supplied with varying P rates, and (2) evaluate Si absorption of rice using foliar- and soil-applied Si fertilizers. Three P rates, (0, 112, and 224 kg ha -1 ) combined with five Si treatments (wollastonite and slag applied at 4.5 ton ha -1 and one foliar Si solution applied at 20, 40 and 80 mg Si L -1 ) and a check were arranged in a randomized complete block design with four replications. The presence of P and Si in the soil created a synergistic effect on soil Al, Mn, and As ( P rice growth and P uptake. Wollastonite and slag application were most effective in raising rice Si content than foliar applied Si ( P production (25%) for rice receiving foliar Si, no supporting evidence was obtained in these experiments to verify leaf surface Si absorption. The application of Si-rich materials to soil still remains the most effective method for enhancing Si uptake by plants.

  20. Can arbuscular mycorrhizal fungi improve grain yield, As uptake and tolerance of rice grown under aerobic conditions?

    Energy Technology Data Exchange (ETDEWEB)

    Li, H. [Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (Hong Kong); Ye, Z.H. [State Key Laboratory for Bio-control, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006 (China); Chan, W.F.; Chen, X.W.; Wu, F.Y. [Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (Hong Kong); Wu, S.C. [Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (Hong Kong); School of Environment and Natural Resources, Zhejiang Agriculture and Forestry University, Lin' an, Zhejiang 311300 (China); Wong, M.H., E-mail: mhwong@hkbu.edu.hk [Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (Hong Kong); School of Environment and Natural Resources, Zhejiang Agriculture and Forestry University, Lin' an, Zhejiang 311300 (China)

    2011-10-15

    The effects of arbuscular mycorrhizal fungi (AMF) -Glomus intraradices and G. geosporum on arsenic (As) and phosphorus (P) uptake by lowland (Guangyinzhan) and upland rice (Handao 502) were investigated in soil, spiked with and without 60 mg As kg{sup -1}. In As-contaminated soil, Guangyinzhan inoculated with G. intraradices or Handao 502 inoculated with G. geosporum enhanced As tolerance, grain P content, grain yield. However, Guangyinzhan inoculated with G. geosporum or Handao 502 inoculated with G. intraradices decreased grain P content, grain yield and the molar ratio of grain P/As content, and increased the As concentration and the ratio of grain/straw As concentration. These results show that rice/AMF combinations had significant (p < 0.05) effects on grain As concentration, grain yield and grain P uptake. The variation in the transfer and uptake of As and P reflected strong functional diversity in AM (arbuscular mycorrhizal) symbioses. - Highlights: > Rice/AMF combinations had significant effects on grain As concentration, grain yield and grain P uptake. > Rice colonized with suitable AMF can increase grain yield. > The variation in the transfer and uptake of As and P reflected strong functional diversity in AM symbioses. - Different rice/AMF combinations had very different effects on arsenic and phosphorus uptake.

  1. Can arbuscular mycorrhizal fungi improve grain yield, As uptake and tolerance of rice grown under aerobic conditions?

    International Nuclear Information System (INIS)

    Li, H.; Ye, Z.H.; Chan, W.F.; Chen, X.W.; Wu, F.Y.; Wu, S.C.; Wong, M.H.

    2011-01-01

    The effects of arbuscular mycorrhizal fungi (AMF) -Glomus intraradices and G. geosporum on arsenic (As) and phosphorus (P) uptake by lowland (Guangyinzhan) and upland rice (Handao 502) were investigated in soil, spiked with and without 60 mg As kg -1 . In As-contaminated soil, Guangyinzhan inoculated with G. intraradices or Handao 502 inoculated with G. geosporum enhanced As tolerance, grain P content, grain yield. However, Guangyinzhan inoculated with G. geosporum or Handao 502 inoculated with G. intraradices decreased grain P content, grain yield and the molar ratio of grain P/As content, and increased the As concentration and the ratio of grain/straw As concentration. These results show that rice/AMF combinations had significant (p < 0.05) effects on grain As concentration, grain yield and grain P uptake. The variation in the transfer and uptake of As and P reflected strong functional diversity in AM (arbuscular mycorrhizal) symbioses. - Highlights: → Rice/AMF combinations had significant effects on grain As concentration, grain yield and grain P uptake. → Rice colonized with suitable AMF can increase grain yield. → The variation in the transfer and uptake of As and P reflected strong functional diversity in AM symbioses. - Different rice/AMF combinations had very different effects on arsenic and phosphorus uptake.

  2. Rice peasants and rice research in Colombia

    NARCIS (Netherlands)

    Spijkers, P.A.N.M.

    1983-01-01

    Rice has been grown as a food crop in Latin America from early colonial times. In Colombia rice became a prominent subsistence crop especially on the north coast where it has been grown since the 17th century, sometimes also as a commercial crop. During the last twenty years there has been a sharp

  3. Nitrogen Fertilizer Deep Placement for Increased Grain Yield and Nitrogen Recovery Efficiency in Rice Grown in Subtropical China

    Directory of Open Access Journals (Sweden)

    Meng Wu

    2017-07-01

    Full Text Available Field plot experiments were conducted over 3 years (from April 2014 to November 2016 in a double-rice (Oryza sativa L. cropping system in subtropical China to evaluate the effects of N fertilizer placement on grain yield and N recovery efficiency (NRE. Different N application methods included: no N application (CK; N broadcast application (NBP; N and NPK deep placement (NDP and NPKDP, respectively. Results showed that grain yield and apparent NRE significantly increased for NDP and NPKDP as compared to NBP. The main reason was that N deep placement (NDP increased the number of productive panicle per m-2. To further evaluate the increase, a pot experiment was conducted to understand the N supply in different soil layers in NDP during the whole rice growing stage and a 15N tracing technique was used in a field experiment to investigate the fate of urea-15N in the rice–soil system during rice growth and at maturity. The pot experiment indicated that NDP could maintain a higher N supply in deep soil layers than N broadcast for 52 days during rice growth. The 15N tracing study showed that NDP could maintain much higher fertilizer N in the 5–20 cm soil layer during rice growth and could induce plant to absorb more N from fertilizer and soil than NBP, which led to higher NRE. One important finding was that NDP and NPKDP significantly increased fertilizer NRE but did not lead to N declined in soil compared to NBP. Compared to NPK, NPKDP induced rice plants to absorb more fertilizer N rather than soil N.

  4. Procedure for rapid determination of δ15N and δ18O values of nitrate: development and application to an irrigated rice paddy watershed.

    Science.gov (United States)

    Yada, Saeko; Nakajima, Yasuhiro; Itahashi, Sunao; Asada, Kei; Yoshikawa, Seiko; Eguchi, Sadao

    2016-01-01

    The dual isotope approach using the stable isotope ratios of nitrate nitrogen (δ(15)N(NO3)) and oxygen (δ(18)O(NO3)) is a strong tool for identifying the history of nitrate in various environments. Basically, a rapid procedure for determining δ(15)N(NO3) and δ(18)O(NO3) values is required to analyze many more samples quickly and thus save on the operational costs of isotope-ratio mass spectrometry (IRMS). We developed a new rapid procedure to save time by pre-treating consecutive samples of nitrous oxide microbially converted from nitrate before IRMS determination. By controlling two six-port valves of the pre-treatment system separately, IRMS determination of the current sample and backflush during the next sample pre-treatment period could be conducted simultaneously. A set of 89 samples was analyzed precisely during a 25-h continuous run (17 min per sample), giving the fastest reported processing time, and simultaneously reducing liquid nitrogen and carrier helium gas consumption by 35%. Application of the procedure to an irrigated rice paddy watershed suggested that nitrate concentrations in river waters decreased in a downstream direction, mainly because of the mixing of nitrate from different sources, without distinct evidence of denitrification. Our procedure should help with more detailed studies of nitrate formation processes in watersheds.

  5. Heavy metal accumulation in soils, plants, and hair samples: an assessment of heavy metal exposure risks from the consumption of vegetables grown on soils previously irrigated with wastewater.

    Science.gov (United States)

    Massaquoi, Lamin Daddy; Ma, Hui; Liu, Xue Hui; Han, Peng Yu; Zuo, Shu-Mei; Hua, Zhong-Xian; Liu, Dian-Wu

    2015-12-01

    It is common knowledge that soils irrigated with wastewater accumulate heavy metals more than those irrigated with cleaner water sources. However, little is known on metal concentrations in soils and cultivars after the cessation of wastewater use. This study assessed the accumulation and health risk of heavy metals 3 years post-wastewater irrigation in soils, vegetables, and farmers' hair. Soils, vegetables, and hair samples were collected from villages previously irrigating with wastewater (experimental villages) and villages with no history of wastewater irrigation (control villages). Soil samples were digested in a mixture of HCL/HNO3/HCLO4/HF. Plants and hair samples were digested in HNO3/HCLO4 mixture. Inductive coupled plasma-optical emission spectrometer (ICP-OES) was used to determine metal concentrations of digested extracts. Study results indicate a persistence of heavy metal concentration in soils and plants from farms previously irrigated with wastewater. In addition, soils previously irrigated with wastewater were severely contaminated with cadmium. Hair metal concentrations of farmers previously irrigating with wastewater were significantly higher (P metal concentrations in hair samples of farmers previously irrigating with wastewater were not associated with current soil metal concentrations. The study concludes that there is a persistence of heavy metals in soils and plants previously irrigated with wastewater, but high metal concentrations in hair samples of farmers cannot be associated with current soil metal concentrations.

  6. Comparative study of the physico-chemical properties of rice and corn starches grown in Indian temperate climate

    Directory of Open Access Journals (Sweden)

    Abida Ali

    2016-01-01

    Full Text Available Starches isolated from the rice (Jhelum and Kohsar and corn (PS-43 and Shalimar-maize cultivars were studied for their physico-chemical and morphological properties. Physico-chemical properties such as composition, water and oil absorption capacity, swelling power, syneresis, freeze–thaw stability and light transmittance showed significant differences among the starches. Amylose contents of starches separated from the Jhelum and Kohsar rice cultivars and PS-43 and Shalimar-maize corn cultivars were 6.33%, 4.90%, 7.52% and 8.09%, respectively. The granular size varied from 5.2 to 5.9 μm for rice starches and 11.4–12.0 μm for corn starches. Transmittance value of gelatinized pastes from all starches progressively decreased up to the 2nd day during refrigerated storage, except Kohsar rice starch which lost its clarity significantly up to 3rd day of storage. The pasting property revealed peak, breakdown and setback viscosity which were in the range of 2479–3021 cP, 962–1713 cP and 1293–2003 cP respectively.

  7. Effects of modified biochar on rhizosphere microecology of rice (Oryza sativa L.) grown in As-contaminated soil.

    Science.gov (United States)

    Liu, Shusi; Lu, Yixin; Yang, Chen; Liu, Chuanping; Ma, Lin; Dang, Zhi

    2017-10-01

    Biochar was carbon-rich and generated by high-temperature pyrolysis of biomass under oxygen-limited conditions. Due to the limitations of surface functional groups and the weakness of surface activity in the field of environmental remediation, the raw biochar frequently was chemically modified to improve its properties with a new performance. In this study, a kind of high-efficiency and low-cost amino biochar modified by nano zero-valent iron (ABC/NZVI) was synthesized and applied to paddy soil contaminated with arsenic (As). Dynamic changes of soil properties, arsenic speciations and rhizosphere microbial communities have been investigated over the whole growth period of rice plants. Pot experiments revealed that the ABC/NZVI could decrease the arsenic concentration in rice straw by 47.9% and increase the content of nitrogen in rice straw by 47.2%. Proportion of Geobacter in soil with ABC/NZVI treatment increased by 175% in tillering period; while Nitrososphaera decreased by 61 and 20% in tillering and maturity, respectively, compared to that of control. ABC/NZVI promotes arsenic immobilization in rhizosphere soil and precipitation on root surface and reduces arsenic accumulation in rice. At the same time, ABC/NZVI would inhibit Nitrososphaera which is related to ammonia oxidation process, and it would have a promising potential as soil amendment to reduce nitrogen loss probably.

  8. Effects of root anatomy and Fe plaque on arsenic uptake by rice seedlings grown in solution culture

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Dan [Department of Environmental Sciences, East China Normal University, Shanghai (China); Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University (Hong Kong); Wu Shengchun; Wu Fuyong [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University (Hong Kong); Deng Hong, E-mail: lilac_deng@yahoo.com.c [Department of Environmental Sciences, East China Normal University, Shanghai (China); Tiantong National Station of Forest Ecosystem, Key Laboratory of Urbanization and Ecological Restoration, East China Normal University, Shanghai 200062 (China); Wong Minghung, E-mail: mhwong@hkbu.edu.h [Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University (Hong Kong)

    2010-08-15

    Hydroponic experiments were carried out to investigate the effects of root anatomy, induced by aeration and stagnation, and Fe plaque on arsenic (III and V) uptake and translocation by rice plants. The results showed that As uptake in rice plants (Gui Chao-2) treated by aeration was decreased due to lower root specific surface area. Rice roots with larger specific surface area tended to form more Fe plaque, and Fe plaque affected As uptake kinetics by changing As influx curves from linear to hyperbolic for As(III) and from hyperbolic to S-curve for As(V). Fe plaque increased As(III and V) adsorption and minimized the effects of root anatomy characteristics on As uptake into roots and subsequently translocation to shoots. Fe plaque increased As(III) uptake rate at As(III) concentrations of 0.5{approx}8 mg L{sup -1}, reduced As(V) uptake rate at low As(V) concentrations (<2 mg L{sup -1}), but increased As uptake rate at high As(V) concentrations (>6 mg L{sup -1}). - Rice root anatomy and Fe plaque affect As uptake.

  9. Effects of root anatomy and Fe plaque on arsenic uptake by rice seedlings grown in solution culture

    International Nuclear Information System (INIS)

    Deng, Dan; Wu Shengchun; Wu Fuyong; Deng Hong; Wong Minghung

    2010-01-01

    Hydroponic experiments were carried out to investigate the effects of root anatomy, induced by aeration and stagnation, and Fe plaque on arsenic (III and V) uptake and translocation by rice plants. The results showed that As uptake in rice plants (Gui Chao-2) treated by aeration was decreased due to lower root specific surface area. Rice roots with larger specific surface area tended to form more Fe plaque, and Fe plaque affected As uptake kinetics by changing As influx curves from linear to hyperbolic for As(III) and from hyperbolic to S-curve for As(V). Fe plaque increased As(III and V) adsorption and minimized the effects of root anatomy characteristics on As uptake into roots and subsequently translocation to shoots. Fe plaque increased As(III) uptake rate at As(III) concentrations of 0.5∼8 mg L -1 , reduced As(V) uptake rate at low As(V) concentrations ( -1 ), but increased As uptake rate at high As(V) concentrations (>6 mg L -1 ). - Rice root anatomy and Fe plaque affect As uptake.

  10. Yield and size of oyster mushroom grown on rice/wheat straw basal substrate supplemented with cotton seed hull.

    Science.gov (United States)

    Yang, Wenjie; Guo, Fengling; Wan, Zhengjie

    2013-10-01

    Oyster mushroom (Pleurotus ostreatus) was cultivated on rice straw basal substrate, wheat straw basal substrate, cotton seed hull basal substrate, and wheat straw or rice straw supplemented with different proportions (15%, 30%, and 45% in rice straw substrate, 20%, 30%, and 40% in wheat straw substrate) of cotton seed hull to find a cost effective substrate. The effect of autoclaved sterilized and non-sterilized substrate on growth and yield of oyster mushroom was also examined. Results indicated that for both sterilized substrate and non-sterilized substrate, oyster mushroom on rice straw and wheat basal substrate have faster mycelial growth rate, comparatively poor surface mycelial density, shorter total colonization period and days from bag opening to primordia formation, lower yield and biological efficiency, lower mushroom weight, longer stipe length and smaller cap diameter than that on cotton seed hull basal substrate. The addition of cotton seed hull to rice straw and wheat straw substrate slowed spawn running, primordial development and fruit body formation. However, increasing the amount of cotton seed hull can increase the uniformity and white of mycelium, yield and biological efficiency, and increase mushroom weight, enlarge cap diameter and shorten stipe length. Compared to the sterilized substrate, the non-sterilized substrate had comparatively higher mycelial growth rate, shorter total colonization period and days from bag opening to primordia formation. However, the non-sterilized substrate did not gave significantly higher mushroom yield and biological efficiency than the sterilized substrate, but some undesirable characteristics, i.e. smaller mushroom cap diameter and relatively long stipe length.

  11. Factors affecting the income from major crops in rice-wheat ecological zone

    International Nuclear Information System (INIS)

    Ashfaq, M.; Naseer, M.Z.; Hassan, S.

    2008-01-01

    Agriculture is an important sector of our economy. About twenty-two percent of national income and 44.8 percent of total employment is generated by this sector. About 66 percent of country's population is living in rural areas and is directly or indirectly linked with agriculture for their livelihood. It also supplies raw materials to industry. The rice-wheat zone of Punjab covers 1.1 million hectare, 72% of wheat is grown in rotation with rice. The main purpose of this paper was to determine the effect of different factors on the productivity and ultimately on income from of major crops (wheat, rice and sugar-cane) in rice-wheat ecological zone. The results show that for wheat crop, land preparation, use of fertilizer and chemicals, for Sugarcane crop, area under cultivation, fertilizer and chemical costs and for rice crop, applications of chemicals, irrigation and land holding were the main determinants of productivity and crop income. (author)

  12. Enhanced UV-B radiation has little effect on growth, delta13C values and pigments of pot-grown rice (Oryza sativa) in the field

    International Nuclear Information System (INIS)

    Kim, H.Y.; Kobayashi, K.; Nouchi, I.; Yoneyama, T.

    1996-01-01

    Predicted increase in ultraviolet-B (UV-B: 280–320 mn) radiation may have adverse impacts on growth and yield of rice (Oryza sativa L.), as has been found in studies hitherto. However, most of the studies were conducted in growth chambers or greenhouses where the plants are generally more sensitive to UV-B than in the field, presumably because of the distorted balance between UV-B and ultraviolet-A as well as PAR. This study was conducted to address the effects of enhanced UV-B on growth and yield of rice under a realistic spectral balance in the field. Three cultivars, “Koshihikari”,‘IR 45’and‘IR 74’were pot-grown and irradiated with enhanced UV-B for most of the growing season in the field at Tsukuba, Japan (36°01′N, 140°07′E). The UV-B enhancement simulated ca 38% depletion of stratospheric ozone at Tsukuba. The results showed no UV-B effects on plant height, numbers of tillers and panicles, dry weight of the plant parts or the grain yield for any of the 3 cultivars. Natural abundance of 13 C in the flag leaves was not altered by the UV-B enhancement either. While UV-absorbing compounds showed no response to the UV-B enhancement, chlorophyll contents decreased with enhanced UV-B. However, the decrease of chlorophyll was limited to an early growth stage with no effect later. We thus found no extraordinary impact of the nearly doubled UV-B radiation on rice in the field, and it would appear that a reliable prediction of the effects of UV-B will require experiments carried out over a number of years under various climatic and solar UV-B regimes. (author)

  13. Soil and water warming accelerates phenology and down-regulation of leaf photosynthesis of rice plants grown under free-air CO2 enrichment (FACE).

    Science.gov (United States)

    Adachi, Minaco; Hasegawa, Toshihiro; Fukayama, Hiroshi; Tokida, Takeshi; Sakai, Hidemitsu; Matsunami, Toshinori; Nakamura, Hirofumi; Sameshima, Ryoji; Okada, Masumi

    2014-02-01

    To enable prediction of future rice production in a changing climate, we need to understand the interactive effects of temperature and elevated [CO2] (E[CO2]). We therefore examined if the effect of E[CO2] on the light-saturated leaf photosynthetic rate (Asat) was affected by soil and water temperature (NT, normal; ET, elevated) under open-field conditions at the rice free-air CO2 enrichment (FACE) facility in Shizukuishi, Japan, in 2007 and 2008. Season-long E[CO2] (+200 µmol mol(-1)) increased Asat by 26%, when averaged over two years, temperature regimes and growth stages. The effect of ET (+2°C) on Asat was not significant at active tillering and heading, but became negative and significant at mid-grain filling; Asat in E[CO2]-ET was higher than in ambient [CO2] (A[CO2])-NT by only 4%. Photosynthetic down-regulation at E[CO2] also became apparent at mid-grain filling; Asat compared at the same [CO2] in the leaf cuvette was significantly lower in plants grown in E[CO2] than in those grown in A[CO2]. The additive effects of E[CO2] and ET decreased Asat by 23% compared with that of A[CO2]-NT plants. Although total crop nitrogen (N) uptake was increased by ET, N allocation to the leaves and to Rubisco was reduced under ET and E[CO2] at mid-grain filling, which resulted in a significant decrease (32%) in the maximum rate of ribulose-1,5-bisphosphate carboxylation on a leaf area basis. Because the change in N allocation was associated with the accelerated phenology in E[CO2]-ET plants, we conclude that soil and water warming accelerates photosynthetic down-regulation at E[CO2].

  14. The influence of acid rain on the intake of trace elements into rice plant from soils

    International Nuclear Information System (INIS)

    Tanizaki, Yoshiyuki; Nakamura, Masaru; Maeno, Tomokazu

    1995-01-01

    Rice plant samples were grown in 14 cultivative pots by irrigation using the six conditions of artificial acid rain waters (pH: 6.5, 6.0, 4.5, 3.5, 3.0 and 2.5) and tap water (pH: 7.5). The rice grain yielded were separated into three parts, i.e., polished rice, bran and chaff, and they were reduced to powder one by one. Twenty six element contents in the three parts of grain (each 14 samples) were determined by a neutron activation analysis. The contents of Cr, Fe, Ni, Zn, Cu, Rb, Mo in the polished rice increased with decreasing of pH of the irrigation waters. The contents of Se and Br, on the contrary, decreased with decreasing of pH of the irrigation waters. Significant changes of the contents were not observed for the elements Na, Al, Cl, Sc, Mn, Co, V. The enrichment factor of trace elements to soils were calculated for the polished rice, bran and chaff. The high enrichments of Cl, Mo, Zn, Se, Cu and Ni were observed in the polished rice. The elements K, Rb, Mn, Mg and Cr were highly concentrated in the bran. (author)

  15. Growth, Yield and WUE of Drip and Sprinkler Irrigated Okra Grown On Sandy Soil Under Semi-Arid Conditions in Southeast Ghana

    DEFF Research Database (Denmark)

    Plauborg, Finn

    Vegetable production systems at the Keta sand spit, Southeast Ghana, are typically managed with excessive amounts of irrigation water and fertilizers on sandy soils with low inherent water and nutrient retention capacities. The shallow groundwater which is the primary irrigation water resource...... is prone to salinization from the Keta lagoon, the Atlantic Ocean and brackish water underneath (Kortatsi and Agyeku, 1999). To ensure the sustainability of vegetable production at the Keta spit, introduction of water saving irrigation systems and improved irrigation management schemes are important. Thus......, the main aim of our study was to explore the water sa ving potential of drip irrigation in order to save the shallow groundwater from over exploitation. A two season study (minor dry season, 2011 and major dry season, 2012) were carried out to determine the okra crop response to the following treatments: 1...

  16. Effect of different fertilization and irrigation methods on nitrogen uptake, intercepted radiation and yield of okra (Abelmoschus esculentum L.) grown in the Keta Sand Spit of Southeast Ghana

    DEFF Research Database (Denmark)

    Danso, E. Oppong; Abenney-Mickson, S.; Sabi, E.B.

    2015-01-01

    spread, (ii) irrigation by sprinkler, fertilized with localized manure, (iii) irrigation by drip, fertilized with localized manure, (iv) irrigation by drip, fertigated with N-K chemical fertilizers (twice during the crop season in the first experiment, weekly in the second and third experiment). Nitrogen...... uptake, crop interception of solar radiation, yield and water productivity were compared among treatments. The crop did not respond well when fertigation was done only twice, probably due to N-leaching. However, in the second and third experiments, when fertigation was done weekly for eight weeks......Three seasons' experiments were conducted in the Keta Sand Spit to test if current use of sprinkler irrigation and animal manure can be substituted by water saving drip fertigation with reduced P supply to okra. The treatments compared were: (i) irrigation by sprinkler, fertilized with manure...

  17. Adaptación del arroz riego (Oryza sativa L. en el Caribe colombiano Adaptation of irrigated rice (Oryza sativa L. in the colombian Caribbean

    Directory of Open Access Journals (Sweden)

    Hermes Aramendiz Tatis

    2011-01-01

    Full Text Available En Colombia, el arroz ocupa el primer lugar en seguridad alimentaria, valor económico y generación de empleo entre los cultivos anuales, siendo el sistema bajo riego más importante. El objetivo fue determinar el progreso, estabilidad y adaptabilidad del rendimiento de arroz bajo riego, en cinco departamentos del caribe colombiano. Se utilizaron datos del Ministerio de Agricultura y Desarrollo Rural, correspondiente a los Departamentos de Córdoba, Bolívar, Magdalena, Cesar y Guajira, durante el periodo 1987-2008. La estimación del progreso del rendimiento se realizó a través del análisis de regresión lineal entre los años (variable explicativa y el rendimiento de grano (variable explicada. La estabilidad se determinó a través del coeficiente de variación para tres períodos consecutivos de cinco años y el último de siete. La adaptabilidad, se realizó con el coeficiente de regresión lineal (bi. Los resultados destacan que el progreso en el rendimiento de grano en el Caribe colombiano, osciló entre 1.15% y 3.36% por año y 52.2 y 168.1 kg.ha-1, especialmente en el Departamento de Bolívar (3.36% por año y 168.1 kg.ha-1. La estabilidad, resultó en general alta (CV4.57 para el rendimiento de grano.In Colombia, the rice crop under irrigation system ranks first in food security, economic value and employment offer among annual crops, becoming the most important. The objective of this study was to quantify increasing, stability and adaptability of irrigated rice in five departments of the Colombian Caribbean area. Data from the Ministry of Agriculture and Rural Development for the departments of Cordoba, Bolivar, Magdalena, Cesar and Guajira, during the year period 1987 to 2008 were used. The increasing in yield was determined using the linear regression analysis among years (independent variable and grain yield (dependent variable in each department. The yield stability was determined by the coefficient of variation across of three

  18. Aplicação de reguladores vegetais na cultura de arroz de terras altas = Effect of vegetal regulators on sprinkler-irrigated highland rice

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Félix Alvarez

    2007-04-01

    Full Text Available O objetivo deste trabalho foi identificar o regulador vegetal e dose mais adequada visando à redução da altura da planta e acamamento e a interferência destes nos componentes da produção e produtividade de grãos de arroz de terras altas irrigado por aspersão. Os tratamentos foram constituídos de três reguladores vegetais e quatro doses. Ocloreto de mepiquat (PIX e o etil-trinexapac (Moddus foram aplicados nas doses 0, 2000, 4000 e 8000 mg L-1 e o paclobutrazol (Paclobutrazol ou Cultar foi aplicado nas doses 0, 1000, 2000 e 4000 mg L-1, do produto comercial. Os reguladores vegetais foram aplicadosno estádio de perfilhamento, utilizando o cultivar Primavera. Constatou-se que a aplicação do etil-trinexapac reduziu a altura da planta e influenciou negativamente os componentes da produção e produtividade de grãos. Não foi identificada uma dose “ideal” que reduzisse a altura da planta e proporcionasse aumento na produtividade de grãos.The present work aims to identify the vegetal regulators and optimum dose to reduce plant height and layering and their influence on production and productivity components in sprinkler-irrigated highland rice grains. Treatments consisted of three vegetal regulators and four doses. Mepiquat chloride (Pix and ethyl-trinexapac (Moddus were applied at doses of 0, 2000, 4000 and 8000 mg L-1, while paclobutrazol (Paclobutrazol was applied at 0, 1000,2000 and 4000 mg L-1, commercial product. The vegetal regulators were applied during the profiling state, utilizing Primavera cultivar. Results showed that ethyl-trinexapac reduced the plant height and influenced negatively grain production and productivity components.No optimum dose was identified to reduce plant height and increase grain productivity.

  19. Deciphering Phosphate Deficiency-Mediated Temporal Effects on Different Root Traits in Rice Grown in a Modified Hydroponic System

    Science.gov (United States)

    Negi, Manisha; Sanagala, Raghavendrarao; Rai, Vandna; Jain, Ajay

    2016-01-01

    Phosphate (Pi), an essential macronutrient for growth and development of plant, is often limiting in soils. Plants have evolved an array of adaptive strategies including modulation of root system architecture (RSA) for optimal acquisition of Pi. In rice, a major staple food, RSA is complex and comprises embryonically developed primary and seminal roots and post-embryonically developed adventitious and lateral roots. Earlier studies have used variant hydroponic systems for documenting the effects of Pi deficiency largely on primary root growth. Here, we report the temporal effects of Pi deficiency in rice genotype MI48 on 15 ontogenetically distinct root traits by using easy-to-assemble and economically viable modified hydroponic system. Effects of Pi deprivation became evident after 4 days- and 7 days-treatments on two and eight different root traits, respectively. The effects of Pi deprivation for 7 days were also evident on different root traits of rice genotype Nagina 22 (N22). There were genotypic differences in the responses of primary root growth along with lateral roots on it and the number and length of seminal and adventitious roots. Notably though, there were attenuating effects of Pi deficiency on the lateral roots on seminal and adventitious roots and total root length in both these genotypes. The study thus revealed both differential and comparable effects of Pi deficiency on different root traits in these genotypes. Pi deficiency also triggered reduction in Pi content and induction of several Pi starvation-responsive (PSR) genes in roots of MI48. Together, the analyses validated the fidelity of this modified hydroponic system for documenting Pi deficiency-mediated effects not only on different traits of RSA but also on physiological and molecular responses. PMID:27200025

  20. Irrigation Water Sources and Time Intervals as Variables on the Presence of Campylobacter spp. and Listeria monocytogenes on Romaine Lettuce Grown in Muck Soil.

    Science.gov (United States)

    Guévremont, Evelyne; Lamoureux, Lisyanne; Généreux, Mylène; Côté, Caroline

    2017-07-01

    Irrigation water has been identified as a possible source of vegetable contamination by foodborne pathogens. Risk management for pathogens such as Campylobacter spp. and Listeria monocytogenes in fields can be influenced by the source of the irrigation water and the time interval between last irrigation and harvest. Plots of romaine lettuce were irrigated with manure-contaminated water or aerated pond water 21, 7, or 3 days prior to harvesting, and water and muck soil samples were collected at each irrigation treatment. Lettuce samples were collected at the end of the trials. The samples were tested for the presence of Campylobacter spp. and L. monocytogenes. Campylobacter coli was isolated from 33% of hog manure samples (n = 9) and from 11% of the contaminated water samples (n = 27), but no lettuce samples were positive (n = 288). L. monocytogenes was not found in manure, and only one sample of manure-contaminated irrigation water (n = 27) and one lettuce sample (n = 288) were positive. No Campylobacter or L. monocytogenes was recovered from the soil samples (n = 288). Because of the low incidence of pathogens, it was not possible to link the contamination of either soil or lettuce with the type of irrigation water. Nevertheless, experimental field trials mimicking real conditions provide new insights into the survival of two significant foodborne pathogens on romaine lettuce.

  1. Effect of Different Levels of Irrigation Water Salinity and Soil Texture on Growth and N Use Efficiency of Tomato and Melochia Grown in Rotation using 15N

    International Nuclear Information System (INIS)

    Darwish, T.M.; El Moujabber, M.; Atallah, T.; El Chami, D.

    2008-01-01

    Increasing water demands and water scarcity imply large farmer's reliance on groundwater on the coastal area leading to water salinization by seawater intrusion. Irrigation using saline water accumulates salts in the soil notably under protected agriculture leading to negative impact on yields. Consequently salt removal by leaching is required. Bioremediation of salt affected soils through a rotation acquires economic and environmental importance. Pot experiments were conducted under plastic house conditions on sandy soil (T1) and clay soil (T2). Three saline water treatments were used: low (S1=1.0 dS.m-1), moderate (S2=2.5 dS.m-1) and high (S3=5.0 dS.m-1). Tomato cv Tyrade (S and G seeds) was planted first, followed by Melochia or Jew's mallow (Corchorus olitorius) for remediation purposes. Each soil was placed in 24 pots and treatments were distributed randomly. Fertigation was done using drip method. Labeled nitrogen 15 N was used to trace the direct and residual effect of nitrogen under different saline conditions. Tomato yield, for the sandy soil, was negatively affected by the higher level of salinity. This effect could be attributed to the smaller buffering capacity of the sand soil. As a result of salinity, there was a remarkable increase in dry matter contents of fruits in the sandy soil only. Texture had a major effect on leaf area index (LAI) with better development in clay soil. Water consumption in the first 200 days of growth period did not show any significant difference among treatments with around 350-375 mm consumed. Nitrogen derived from fertilizers (% Ndff) was not affected by the soil texture or by the salinity. N yield and use efficiency were higher in the clay soil texture. Moreover, yield and Ndff in Melochia plants were negatively affected due to salt accumulation in the soil. Counting for all recovered N in the tomato-Melochia rotation, N use efficiency was higher in plants grown on clay soil (47%) compared to sandy soil (37.5%). (author)

  2. Public Health Risk Assessment of Heavy Metal Uptake by Vegetables Grown at a Waste-water-Irrigated Site in Dhaka, Bangladesh

    Directory of Open Access Journals (Sweden)

    Mohammad Shakhaoat Hossain

    2015-01-01

    Conclusions. Higher values in the metal pollution index and health risk index indicate heavy metal contamination in wastewater-irrigated soils that present the potential for a significant negative impact on human health.

  3. REGULATED DEFICIT IRRIGATION AND DIFFERENT MULCH TYPES ON FRUIT QUALITY AND YIELD OF WATERMELON

    Directory of Open Access Journals (Sweden)

    KLEITON ROCHA SARAIVA

    2017-01-01

    Full Text Available The objective of this work was to assess the pulp resistance, soluble solids and yield of watermelon fruits grown under different irrigation managements (determined by the ISAREG model and mulches, and their interactions. After a survey carried out on local producers, two experiments were conducted, using a completely randomized block design in split - plot arrangement with four replications, in the Teaching, Research and Extension Unit (UEPE of the Federal Institute of Ceara (IFCE, Jaguaribe - Apodi Irrigation District (DIJA, State of Ceara, Brazil. The treatments consisted of four irrigation managements in the plots, M1 (100% of the available - water capacity (AWC of the soil, M2 (80%, M3 (60% and M4 (average water depth used by local producers and four mulch types in the sub - plots, without mulching (C0 with rice husk (C1, white plastic (C2 and black plastic (C3 as mulches. The results were subjected to analysis of variance, and significant results were subjected to regression (irrigation managements, average test (mulches and trend graphs (interaction between the factors. The irrigation management practiced during the watermelon crop cycle by the local producers of the Irrigation District of Jaguaribe - Apodi (DIJA in the State of Ceara, Brazil, is not appropriated, since they usually apply more water than the highest water depth determined by the ISAREG model (100% of the AWC. The plants grown under irrigation water depth of 365.20 mm (M1 and soils with mulches of rice husk or white plastic had the highest yields and fruits with better quality of soluble solids and pulp resistance.

  4. Factors affecting variation in CH4 emission from paddy soils grown with different rice cultivars: A pot experiment

    Science.gov (United States)

    Watanabe, Akira; Kimura, Makoto

    1998-08-01

    The growth of rice plants greatly influences CH4 emission from paddy fields through the supply of organic materials such as root exudates and sloughed tissues, the release of oxygen to the root environment, and the transfer of CH4 from the rhizosphere into the atmosphere through the aerenchyma. In the present pot experiments, the effects of the release of water-soluble organic substances from roots, the air space in roots, and the CH4-oxidizing capacity of roots on intervarietal differences in CH4 emission were examined using three Japonica type cultivars (Norin 25, Nipponbare, and Aoinokaze), which differ in morphological properties. The CH4 emission rates varied among the cultivars from mid-July (tillering stage) to the beginning of September (heading stage).Total CH4 emission throughout the rice growth period was largest for Norin 25, followed by Nipponbare, and Aoinokaze. In August, the rate of release of water-soluble organic substances from roots was largest for Norin 25. The air space in roots was also largest in Norin 25 and least in Aoinokaze. The stable carbon isotopic ratios (δ13C) of CH4 in roots were 3-10‰ higher than those in soil in August. The difference in δ13C values of CH4 between roots and soil was largest for Aoinokaze and smallest for Norin 25. In September, the difference in δ13C values of CH4 between roots and soil became small (2-3‰). These findings suggest that the proportion of CH4 oxidation in the rhizosphere was largest in the cultivar which emitted the smallest amount of CH4 and that the proportion became smaller with continued plant growth.

  5. Contrasting effects of elevated CO2 on Cu and Cd uptake by different rice varieties grown on contaminated soils with two levels of metals: Implication for phytoextraction and food safety

    International Nuclear Information System (INIS)

    Li Zhongyang; Tang Shirong; Deng Xiaofang; Wang Ruigang; Song Zhengguo

    2010-01-01

    A pot experiment in six open-top chambers with two levels of CO 2 and two multi-metal contaminated soils was conducted to investigate combined effects of elevated CO 2 levels and metals (Cu and Cd) on rice. Elevated CO 2 significantly increased the total dry weight biomass of six Chinese rice by 20-108 and 32-142% for low and high levels of contaminated soils, respectively. We observed dilution/little varied phenomena in grain Cu concentration in six rice varieties grown on both contaminated soils under elevated CO 2 . We found significantly higher Cd concentrations in the parts of three rice varieties under elevated CO 2 , but lower levels for the others. Two major conclusions can be drawn from our study: (1) rice varieties with significantly increased biomass and metal uptake under elevated CO 2 exhibit greater potential for phytoextraction and (2) given expected global increases in CO 2 concentration, CO 2 -induced accumulation of metals in rice might be a component contributing to the potential health risk in the future, with Cd being a more important threat to human health than Cu.

  6. Contrasting effects of elevated CO{sub 2} on Cu and Cd uptake by different rice varieties grown on contaminated soils with two levels of metals: Implication for phytoextraction and food safety

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhongyang [Centre for Research in Ecotoxicology and Environmental Remediation, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191 (China); Open Key Laboratory of Agro-environment and Agro-product Safety of Ministry of Agriculture, Tianjin (China); Tang Shirong, E-mail: tangshir@hotmail.com [Centre for Research in Ecotoxicology and Environmental Remediation, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191 (China); Open Key Laboratory of Agro-environment and Agro-product Safety of Ministry of Agriculture, Tianjin (China); Deng Xiaofang; Wang Ruigang; Song Zhengguo [Centre for Research in Ecotoxicology and Environmental Remediation, Agro-Environmental Protection Institute, Ministry of Agriculture, Tianjin 300191 (China); Open Key Laboratory of Agro-environment and Agro-product Safety of Ministry of Agriculture, Tianjin (China)

    2010-05-15

    A pot experiment in six open-top chambers with two levels of CO{sub 2} and two multi-metal contaminated soils was conducted to investigate combined effects of elevated CO{sub 2} levels and metals (Cu and Cd) on rice. Elevated CO{sub 2} significantly increased the total dry weight biomass of six Chinese rice by 20-108 and 32-142% for low and high levels of contaminated soils, respectively. We observed dilution/little varied phenomena in grain Cu concentration in six rice varieties grown on both contaminated soils under elevated CO{sub 2}. We found significantly higher Cd concentrations in the parts of three rice varieties under elevated CO{sub 2}, but lower levels for the others. Two major conclusions can be drawn from our study: (1) rice varieties with significantly increased biomass and metal uptake under elevated CO{sub 2} exhibit greater potential for phytoextraction and (2) given expected global increases in CO{sub 2} concentration, CO{sub 2}-induced accumulation of metals in rice might be a component contributing to the potential health risk in the future, with Cd being a more important threat to human health than Cu.

  7. Effects of elevated ozone on leaf {delta}{sup 13}C and leaf conductance of plant species grown in semi-natural grassland with or without irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Jaeggi, M. [Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Air Pollution/Climate Group, CH-8046 Zurich (Switzerland)]. E-mail: maya.jaeggi@psi.ch; Saurer, M. [Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Volk, M. [Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Air Pollution/Climate Group, CH-8046 Zurich (Switzerland); Fuhrer, J. [Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Air Pollution/Climate Group, CH-8046 Zurich (Switzerland)

    2005-03-01

    Stable carbon isotope ratios ({delta}{sup 13}C) and leaf conductance (g{sub s}) were measured (2002, 2003) in Holcus lanatus L., Plantago lanceolata L. Ranunculus friesianus (Jord.), and Trifolium pratense L. at two levels of ozone (O{sub 3}) with or without irrigation. In non-irrigated control plots, R. friesianus showed the least negative {delta}{sup 13}C, and the smallest response to the treatments. Irrigation caused more negative {delta}{sup 13}C, especially in H. lanatus. Irrespective of irrigation, O{sub 3} increased {delta}{sup 13}C in relationship to a decrease in g{sub s} in P. lanceolata and T. pratense. The strongest effect of O{sub 3} on {delta}{sup 13}C occurred in the absence of irrigation, suggesting that under field conditions lack of moisture in the top soil does not always lead to protection from O{sub 3} uptake. It is concluded that in species such as T. pratense plants can maintain stomatal O{sub 3} uptake during dry periods when roots can reach deeper soil layers where water is not limiting. - Under natural field conditions, lack of precipitation may not protect semi-natural vegetation from O{sub 3} effects on leaf gas exchange.

  8. Effects of elevated ozone on leaf δ13C and leaf conductance of plant species grown in semi-natural grassland with or without irrigation

    International Nuclear Information System (INIS)

    Jaeggi, M.; Saurer, M.; Volk, M.; Fuhrer, J.

    2005-01-01

    Stable carbon isotope ratios (δ 13 C) and leaf conductance (g s ) were measured (2002, 2003) in Holcus lanatus L., Plantago lanceolata L. Ranunculus friesianus (Jord.), and Trifolium pratense L. at two levels of ozone (O 3 ) with or without irrigation. In non-irrigated control plots, R. friesianus showed the least negative δ 13 C, and the smallest response to the treatments. Irrigation caused more negative δ 13 C, especially in H. lanatus. Irrespective of irrigation, O 3 increased δ 13 C in relationship to a decrease in g s in P. lanceolata and T. pratense. The strongest effect of O 3 on δ 13 C occurred in the absence of irrigation, suggesting that under field conditions lack of moisture in the top soil does not always lead to protection from O 3 uptake. It is concluded that in species such as T. pratense plants can maintain stomatal O 3 uptake during dry periods when roots can reach deeper soil layers where water is not limiting. - Under natural field conditions, lack of precipitation may not protect semi-natural vegetation from O 3 effects on leaf gas exchange

  9. Efeito do bentazon e bentazon + dichlorprop na cultura do arroz irrigado e sobre as plantas daninhas Effect of bentazon and bentazon + dichlorprop on irrigated rice and weeds

    Directory of Open Access Journals (Sweden)

    C.A.L. dos Santos

    1979-06-01

    Full Text Available Foi instalado um experimento de campo, em solo barrento, com a finalidade de se verificar o efeito do bentazon e da mistura de bentazon + dichlorprop sobre o desenvolvimento do arroz em cultura irrigada e sobre o controle das plantas daninhas. Os tratamentos utilizados foram os seguintes: bentazon á 0,75-1,00 e1,50 kg/ha; bentazon + dichlorprop a 0,80 + 1,00 e 1,00 + 1,40 kg/ha; propanil a 4,20 kg/ha (tratamento padrão; testemunha capinada e testemunha sem capina. Todas as pulverizações foram realizadas em pósemergência. As plantas daninhas encontradas no experimento foram: capituva - Echinochloa colonum (L Link, tiririca amarela - Cyperus esculentus L., beldroega - Portulaca oleracea L. e carurú comum - Amaranthus viridis L. Bentazon a 1,00 e 1,50 kg/ha e bentazon + dichlorprop a 1,00 + 1,40 kg/ha foram eficientes no controle de P. oleracea, A. viridis e C. esculentus; já a dose menor de bentazon apresentou bons resultados contra P. oleracea e A. viridis, enquanto que a dose menor de bentazon + dichlorprop controlou apenas P. oleracea. Propanil, de uma maneira geral, proporcionou eficiente ação sobre as plantas daninhas. Nas condições em que foi realizado o experimento nenhum dos herbicidas, nas suas respectivas doses, apresentou fitotoxicidade para as plantas de arroz da variedade IAC-435 ou prejudicou a produção da cultura.Bentazon at 0.75 - 1.00 and 1.50 kg/ha a.i ., bentazon + dichlorprop at 0.80 + 1.00 and 1.00 + 1.40 kg and propanil at 4.20 kg were applied in post-emergence on irrigated rice, against the following weeds: Echinochloa colonum (L. Link, Cy-perus esc-ulentus L., Portulaca oleracea L. and Amaranthus viridis L. Bentazon at 1.00 - 1.50 kg and bentazon + dichlorprop at 1.00 + 1.40 kg gave good control of P. oleracea, A. viridis and C. esculentus; bentazon at 0.75 kg controlled P. oleracea and A. viridis; bentazon + dichlorprop at 0.80 + 1.00 kg only showed effeciency for P. oleracea; propanil, in general, gave good

  10. Mitigating arsenic contamination in rice plants with an aquatic fern, Marsilea minuta.

    Science.gov (United States)

    Hassi, Ummehani; Hossain, Md Tawhid; Huq, S M Imamul

    2017-10-10

    Dangers of arsenic contamination are well known in human civilization. The threat increases when arsenic is accumulated in food and livestock through irrigated crops or animal food. Hence, it is important to mitigate the effects of arsenic as much as possible. This paper discusses a process for reducing the level of arsenic in different parts of rice plants with an aquatic fern, Marsilea minuta L. A pot experiment was done to study the possibility of using Marsilea minuta as a phytoremediator of arsenic. Rice and Marsilea minuta were allowed to grow together in soils. As a control, Marsilea minuta was also cultured alone in the presence and absence of arsenic (applied at 1 mg/L as irrigation water). We did not find any significant change in the growth of rice due to the association of Marsilea minuta, though it showed a reduction of approximately 58.64% arsenic accumulation in the roots of rice grown with the association of fern compared to that grown without fern. We measured a bioaccumulation factor (BF) of > 5.34, indicating that Marsilea minuta could be a good phytoremediator of arsenic in rice fields.

  11. Risk Assessment of Heavy Metal Contamination on Vegetables Grown in Long-term Wastewater Irrigated Urban Farming Sites in Accra, Ghana

    DEFF Research Database (Denmark)

    Lente, I.; Keraita, Bernard; Drechsel, P.

    2012-01-01

    Assessment was done of heavy-metal contamination and its related health risks in urban vegetable farming in Accra. Samples of irrigation water (n = 120), soil (n = 144) and five different kinds of vegetable (n = 240) were collected and analyzed for copper, zinc, lead, cadmium, chromium, nickel an...

  12. Mapping regional risks from climate change for rainfed rice cultivation in India.

    Science.gov (United States)

    Singh, Kuntal; McClean, Colin J; Büker, Patrick; Hartley, Sue E; Hill, Jane K

    2017-09-01

    Global warming is predicted to increase in the future, with detrimental consequences for rainfed crops that are dependent on natural rainfall (i.e. non-irrigated). Given that many crops grown under rainfed conditions support the livelihoods of low-income farmers, it is important to highlight the vulnerability of rainfed areas to climate change in order to anticipate potential risks to food security. In this paper, we focus on India, where ~ 50% of rice is grown under rainfed conditions, and we employ statistical models (climate envelope models (CEMs) and boosted regression trees (BRTs)) to map changes in climate suitability for rainfed rice cultivation at a regional level (~ 18 × 18 km cell resolution) under projected future (2050) climate change (IPCC RCPs 2.6 and 8.5, using three GCMs: BCC-CSM1.1, MIROC-ESM-CHEM, and HadGEM2-ES). We quantify the occurrence of rice (whether or not rainfed rice is commonly grown, using CEMs) and rice extent (area under cultivation, using BRTs) during the summer monsoon in relation to four climate variables that affect rice growth and yield namely ratio of precipitation to evapotranspiration ( PER ), maximum and minimum temperatures ( T max and T min ), and total rainfall during harvesting. Our models described the occurrence and extent of rice very well (CEMs for occurrence, ensemble AUC = 0.92; BRTs for extent, Pearson's r = 0.87). PER was the most important predictor of rainfed rice occurrence, and it was positively related to rainfed rice area, but all four climate variables were important for determining the extent of rice cultivation. Our models project that 15%-40% of current rainfed rice growing areas will be at risk (i.e. decline in climate suitability or become completely unsuitable). However, our models project considerable variation across India in the impact of future climate change: eastern and northern India are the locations most at risk, but parts of central and western India may benefit from increased

  13. Determination of trace concentrations of aluminium in rice samples by INAA and PIGE methods

    International Nuclear Information System (INIS)

    Nanda, B.B.; Biswal, R.R.; Acharya, R.; Pujari, P.K.

    2015-01-01

    Aluminium is one of the toxic elements entering human body mainly through food and food products. Though its bioavailability is very less, it is necessary to evaluate its total concentrations in food and food products entering to the body through. In order to evaluate total aluminium contents in various food items for daily dietary intake of aluminum, authors have systematically planned to carry out experiments in various food items including rice. Rice is the main food in many parts of India as well as in Odisha. Rice samples under study belong to three categories; (i) various rice samples from local market, (ii) various rice samples grown in similar irrigation (soil and water) conditions and (iii) same variety of rice with different irrigation conditions. Solid samples (pre-cleaned) were powdered, homogenized and taken for analysis by two nuclear analytical techniques (NATs) namely instrumental neutron activation analysis (INAA) using reactor neutrons at BARC and particle induced gamma ray emission (PIGE) using 4 MeV proton beam (20 nA current) from 3 MV Tandetron at IOP, Bhubaneswar in conjunction with high resolution gamma-ray spectrometry. Samples of 10-50 mg for INAA and 250 mg (pelletized in cellulose) for PIGE were used for experiments. For INAA, samples were irradiated at PCF, Dhruva reactor for 1 minute

  14. SOIL N, P AND K CONCENTRATIONS AND RICE YIELD INCREASED DUE TO THE APPLICATION OF Azolla pinnata

    Directory of Open Access Journals (Sweden)

    A. Arivin Rivaie*

    2014-01-01

    Full Text Available Many studies showed that application of Azolla pinnata as biofertilizer improved soil fertility some agricultural crops, including rice, whereas farmers in Lampung consider that A. pinnata suppresses growth of rice seedlings, so they throw it field by raising irrigation water surface. Information on effects A. pinnata application on changes in nutrient availability and rice yield obtained from paddy fields of regions still rare. A study was carried out to investigate effects of different rates of A. pinnata on changes in N, P, K concentrations in paddy soils, N uptake, and rice yield. A well-irrigated paddy field was incorporated with A. pinnata, and then rice seedlings of Ciherang variety had been grown from June up to December 2009. Results: application of A. pinnata at dose of five t per ha increased concentration of N, P and K as well as rice yield. A. pinnata had a relatively high N content, ie 2.43 percent. Application of A. pinnata of 7.5 t per ha increased significantly available soil P, indicated that A. pinnata requires a fairly high P to grow optimally. Application of A. pinnata of 7.5 t per ha gave highest dry grain yield, suggests that application A. pinnata did not suppress rice yield, even use of A. pinnata as organic matter source will help to conserve fossil fuels and foreign exchange as well as will allow more paddy fields that can be fertilized by N.

  15. Effects Of Elevated Ozone On Leaf {delta} {sup 13} C And Leaf Conductance Of Plant Species Grown In Semi-Natural Grassland With Or Without Irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Jaeggi, M.; Saurer, M.; Volk, M. [Agroscope-FAL (Switzerland); Fuhrer, J. [Agroscope-FAL (Switzerland)

    2005-03-01

    At the Swiss prealpine site Le Mouret (754 m a.s.l. 46deg 45min N / 7deg 10min E), semi-natural grassland species were kept under ambient or elevated ozone, paired with or without additional irrigation. Two of the four investigated grassland species showed an additive increase in {sup 13}C-values under drought and elevated ozone conditions. (author)

  16. Prevalence of Rice Yellow Mottle Virus (RYMV) on Rice Plants ...

    African Journals Online (AJOL)

    Abstract. Incidence of Rice yellow mottle virus (RYMV) on rice plants (ofada) grown in two local government areas (LGAs) of Ogun State had been evaluated during a two year field survey. Six month old rice plants were observed for symptom expression and leaf samples collected for serological indexing. Of the 60 leaf ...

  17. Cultivares de arroz irrigado e nutrientes na água de drenagem em diferentes sistemas de cultivos Irrigated rice cultivars and drainnage water nutrient under differnt managements systems

    Directory of Open Access Journals (Sweden)

    Lauro Weber

    2003-02-01

    components of four irrigated rice cultivars under different management systems, as well as, to measure the concentration of nutrients in the initial drainage water. The research was conducted during the 1998/99 growing season on a lowland area on a PLANOSOIL located at the Federal University of Santa Maria-RS, Brazil. The rice cultivars were IRGA 417, EL PASO 144, BRS TAIM and EPAGRI 108. The management systems were: conventional and minimum tillage and pre-germinated and "mix" of pre-germinated and seedlings transplants. The experimental design was a randomized aplit block with four replications. The conventional and minimum tillage were seeded in November 01st, 1998 and the pre-germinated and mix of pre-germinated and seedlings transplants were estabhished in November 18th, 1998. Seed yield was affected by management system except for the cultivar EL PASO 144 that had the same yield regardless treatments. EPAGRI 108 had the highest average yields, 8349kg ha-1. The highest number of panicles per square meter was observed in the pre-germinated and mix pre-germinated systems. The transplanted seedlings had the highest number of seeds per panicles. Regardless the management systems, EL PASO 144 presented thehighest number of seeds per panicle and EPAGRI 108 the heavier seeds. Nutrient concentration in the initial dreinage water was similar in all systems with average N, P, K, Ca, Mg and Fe concentrations of 5.02, 2.06, 10.33, 6.38, 3.51 and 2.56 mg l-1, respectively.

  18. Effect of selenium application on arsenic uptake in rice (Oryza sativa L.).

    Science.gov (United States)

    Kaur, Sumandeep; Singh, Dhanwinder; Singh, Kuldip

    2017-09-01

    Alluvial aquifers of the agrarian state of Punjab of southwestern arid zone used for irrigation of rice crops are rich in arsenic concentration. In the present study, rice (Oryza sativa L.) crops were raised in pots in a greenhouse with a purpose to study whether selenium (Se) application was effective in ameliorating As uptake. The rice crop was irrigated with arsenic laced water (0, 2.5, 5.0, 10.0 μM As L -1 ) throughout the growing period, without and with selenium (0.05 and 0.10 mg kg -1 ) added through mustard biomass, grown ex situ in seleniferous soil. Arsenic uptake and dry matter yield in different parts of the rice crop were assayed after application of As alone and simultaneous supplementations (As + Se). An antagonistic interaction between Se and As was observed. Addition of As through irrigation water significantly reduced yield of rice grain, straw and root. However, subsequent addition of Se helped in mitigating the harmful effect of As and countered the yield reduction caused due to As toxicity. The effect of Se on dry matter yield was more pronounced at its higher dose (0.10 mg kg -1 ) as compared to its lower dose (0.05 mg kg -1 ). The presence of Se either alone or added along with As significantly reduced the As concentration and its uptake by different parts of rice and higher reduction in As concentration was observed with addition of the highest level of applied Se (0.10 mg kg -1 ). Our observations indicated that Se supplementation might be favourable to reduce As accumulation and toxicity in rice crops.

  19. Geoscience research helps rice farmers mitigate climate change and world hunger

    Science.gov (United States)

    Runkle, B.; Suvocarev, K.; Reba, M. L.

    2017-12-01

    Rice is a globally important crop - it comprises 30% of total human caloric consumption - and will be an important crop in the face of expanding population growth. Unfortunately, it is often grown in flooded paddies whose swampy conditions allow microbes to produce the strong greenhouse gas, methane. Over 10% of anthropogenic methane emission to the atmosphere are attributed to rice cultivation. Fortunately, a water-saving irrigation method known as Alternate Wetting and Drying can reduce methane emissions by periodically drying the soil. In our experiments, the method has no effect on rice harvest yields. In our research with rice farmers in Arkansas, we work to evaluate the amount of methane reductions on different fields with this irrigation practice. This research aims to expand the scientific basis for carbon emission reductions programs that enable farmers to be paid for implementing this practice. There are still gaps in our knowledge about how much methane is produced and under what conditions. Our research involves the continuous detection of field methane emissions and correlates then to changes in environmental conditions like the height and temperature of paddy water. Understanding these relationships may help more farmers qualify for credits in the growing carbon emission reductions programs. Because many farmers are already collecting information about their irrigation practices to reduce water applications, we aim to help them re-use this data to more quickly qualify for carbon emissions reductions payments.

  20. Biochar application mode influences nitrogen leaching and NH3 volatilization losses in a rice paddy soil irrigated with N-rich wastewater.

    Science.gov (United States)

    Sun, Haijun; Min, Ju; Zhang, Hailin; Feng, Yanfang; Lu, Kouping; Shi, Weiming; Yu, Min; Li, Xuewen

    2017-07-11

    Impacts of biochar application mode on nitrogen (N) leaching, ammonia (NH 3 ) volatilization, rice grain yield and N use efficiency (NUE) are not well understood. Therefore, a field experiment was conducted to evaluate those impacts in a rice paddy soil received 225 kg N ha -1 from either urea or N-rich wastewater. One treatment received 10 t ha -1 biochar with the basal fertilization, and the other received same total amount of biochar but split applied with the three split N applications with same ratio as N fertilizer split ratio (40%, 30% and 30%). Results showed that N leaching loads were 4.20-6.22 kg ha -1 . Biochar one-time application reduced N leaching by 23.1%, and biochar split application further reduced N leaching by 32.4%. Total NH 3 volatilization loss was 15.5-24.5 kg ha -1 . Biochar one-time application did not influence the NH 3 volatilization, but biochar split application stimulated the cumulative NH 3 volatilization by 57.7%. Both biochar treatments had no influence on NUE and rice grain yield. In conclusion, biochar application mode indeed influences the N leaching and NH 3 volatilization in rice paddy soils, and biochar one-time application should be recommended for reducing N leaching without increasing NH 3 volatilization.

  1. Competição inicial entre Cyperus esculentus e arroz irrigado em condições de casa-de-vegetação Competition between Cyperus esculentus and irrigated rice under green house conditions

    Directory of Open Access Journals (Sweden)

    E. A. L. Erasmo

    2000-08-01

    Full Text Available Com o objetivo de avaliar o efeito competitivo de Cyperus esculentus sobre o crescimento inicial da cultura do arroz irrigado, foi instalado um experimento em casa-devegetação, na Estação Experimental da Faculdade de Agronomia - UNITINS, no munícipio de Gurupi-TO. O delineamento estatístico utilizado foi um fatorial 5x4 com três repetições completamente casualizado. Os tratamentos constaram de cinco períodos de convivência do arroz com C. esculentus (15, 25, 35, 45 e 60 dias após a emergência da cultura e quatro densidades de C. esculentus (0, 2, 4 e 8 tubérculos/vaso, correspondentes a 0; 71; 142 e 286 plantas de C. esculentus por m2, respectivamente. No final de cada período foram avaliados na cultura do arroz os seguintes parâmetros: matéria seca de plantas/vaso; área foliar/planta; matéria seca de perfilhos/vaso; n.º de perfilhos/vaso e altura média de plantas. Os resultados mostraram que o efeito da presença de C. esculentus foi mais marcante nas densidades de quatro e oito tubérculos/vaso a partir dos 35 dias de convivência. O parâmetro mais afetado foi a matéria seca de plantas/vaso, como resultado do decréscimo do número de perfilhos/vaso. A altura das plantas de arroz irrigado não foi afetada pela presença da planta daninha em nenhum período de convivência.With the objective of evaluating the competitive effect of Cyperus esculentus on the growth and production of the culture of irrigated rice, experiments were installed in green house, in the Experimental Station of the School of Agronomy - UNITINS, in Gurupi, State of Tocantins, Brazil. The statistical design used in the experiments was a factorial plot 5x4 with three replications, completely randomized. The treatments consisted of five periods of coexistence of the rice with Cyperus esculentus (15, 25, 35, 45 and 60 days after the emergency - D.A.E, of the rice and four densities of C. esculentus (0, 2, 4 and 8 tuber/pots corresponding to 0; 71; 142 e

  2. Sistemas de cultivo de arroz irrigado e a compactação de um Planossolo Tillage systems of irrigated rice and compaction of a Planosol

    Directory of Open Access Journals (Sweden)

    Alceu Pedrotti

    2001-04-01

    Full Text Available Em 1993 foi avaliada a compactação de um Planossolo cultivado sob diferentes sistemas de manejo, medindo-se a densidade do solo, por meio do método do anel volumétrico, em três camadas de solo. Os tratamentos consistiram de seis sistemas de manejo, selecionados de um experimento conduzido na Embrapa-Centro de Pesquisa Agropecuária de Clima Temperado, desde 1985. Observaram-se, de maneira geral, valores altos de densidade do solo; na primeira camada de solo (0-10 cm o sistema que apresentou o menor valor foi o cultivo de arroz em plantio direto sob a resteva do azevém e nos sistemas que envolvem maior mobilização do solo (arroz contínuo e rotação arroz-soja-milho os valores de densidade do solo foram maiores em relação aos sistemas de preparo reduzido do solo (azevém x arroz plantio direto e soja x arroz plantio direto. Ocorreu maior compactação, em relação à primeira camada, na camada intermediária (1020 cm, em todos os sistemas de cultivo, exceto no sistema de rotação arroz-soja-milho, no qual não houve diferença de densidade entre as camadas de solo.In 1993, it was evaluated the compaction of a Planosol (Albaqualf submitted to different tillage systems, measuring soil density through the volumetric ring method, in three layers. Treatments consisted of six tillage systems selected from an experiment conducted at Embrapa-Centro de Pesquisa Agropecuária de Clima Temperado, Pelotas, RS, Brazil, since 1985. High soil density values were obtained; in the first layer (0-10 cm, the no-tillage rice cultivation on the rye-grass straw was the system with the lowest value. The systems that involved more soil mobilization (rice continuous and rotation rice-soybeans-maize resulted in higher soil density values compared to the reduced preparing systems (rye-grass x rice in zero tillage and soybean x rice in zero tillage. Compacted structures were identified in the intermediate layer (10-20 cm in all tillage systems, except for the

  3. Effect of parboiling on the formation of resistant starch, digestibility and functional properties of rice flour from different varieties grown in Sri Lanka.

    Science.gov (United States)

    Gunaratne, Anil; Kao, Wu; Ratnayaka, Jennet; Collado, Lilia; Corke, Harold

    2013-08-30

    Hydrothermal treatment used in parboiling could induce formation of novel starch properties having potential food applications. In the current work, functional, digestible and retrogradation properties of flour from non-parboiled and steamed parboiled six rice varieties with high amylose content of around 30% but differing in length and width ratio were investigated and compared. The parboiling process reduced swelling volume and amylose leaching in all tested varieties. Among the varieties studied, the resistant starch content ranged from 1.6% in AT 306 to 0.46% in BG 357. Parboiling reduced the resistant starch content in AT 306 by about 50%, but it did not significantly affect the resistant starch content of the other varieties. The amylose-lipid complex remained unchanged after parboiling. Amylopectin retrogradation was not observed in parboiled rice. Amylose retrogradation was not seen except for AT 306. Pasting behaviour of parboiled rice flours showed high pasting stability and low setback. Flours were more susceptible to enzymatic hydrolysis after parboiling. Partial gelatinisation during parboiling was sufficient to produce grains with excellent milling quality showing a head rice recovery that ranged from 98% to 100% among the varieties studied. Degree of gelatinisation is the most important factor that determines the high head rice recovery. High pasting stability and low setback of flour of parboiled rice indicate some potential food applications. © 2013 Society of Chemical Industry.

  4. Effects of water management on arsenic and cadmium speciation and accumulation in an upland rice cultivar.

    Science.gov (United States)

    Hu, Pengjie; Ouyang, Younan; Wu, Longhua; Shen, Libo; Luo, Yongming; Christie, Peter

    2015-01-01

    Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic (As) and cadmium (Cd) in Brazilian upland rice growing in soils polluted with both As and Cd. In the pot experiment constant and intermittent flooding treatments gave 3-16 times higher As concentrations in soil solution than did aerobic conditions but Cd showed the opposite trend. Compared to arsenate, there were more marked changes in the arsenite concentrations in the soil solution as water management shifted, and therefore arsenite concentrations dominated the As speciation and bioavailability in the soil. In the field experiment As concentrations in the rice grains increased from 0.14 to 0.21 mg/kg while Cd concentrations decreased from 0.21 to 0.02 mg/kg with increasing irrigation ranging from aerobic to constantly flooding conditions. Among the various water regimes the conventional irrigation treatment produced the highest rice grain yield of 6.29 tons/ha. The As speciation analysis reveals that the accumulation of dimethylarsinic acid (from 11.3% to 61.7%) made a greater contribution to the increase in total As in brown rice in the intermittent and constant flooding treatments compared to the intermittent-aerobic treatment. Thus, water management exerted opposite effects on Cd and As speciation and bioavailability in the soil and consequently on their accumulation in the upland rice. Special care is required when irrigation regime methods are employed to mitigate the accumulation of metal(loid)s in the grain of rice grown in soils polluted with both As and Cd. Copyright © 2014. Published by Elsevier B.V.

  5. [Analysis of mineral elements of sunflower (Helianthus annuus L.) grown on saline land in Hetao Irrigation District by ICP-AES].

    Science.gov (United States)

    Tong, Wen-Jie; Chen, Fu; Wen, Xin-Ya

    2014-01-01

    The absorption and accumulation of ten mineral elements in four kinds of organs (root, steam, leaf and flower disc) in Helianthus annuus L. plants cultured in Hetao Irrigation District under different level of salinity stress were determined by ICP-AES with wet digestion (HNO3 + HClO4). The results showed that: (1) The contents of Fe, Mn, Zn, Ca, and Na were highest in roots, so was K in stems, B and Mg in leaves and P in flower discs, while no significant difference was detected in the content of Cu among these organs; (2) The cumulants of Ca, Mg, P, Cu, B and Zn were highest in flower discs, so were Na, Fe and Mn in roots and K in stems; (3) In sunflower plants, the proportion of mineral element cumulant for K : Ca : Mg : P : Na was 16.71 : 5.23 : 3.86 : 1.23 : 1.00, and for Zn : Fe : B : Mn: Cu was 56.28 : 27.75 : 1.93 : 1.17 : 1.00, respectively; (4) The effect of salinity stress on absorption of mineral elements differed according to the kind of organ and element, root was the most sensitive to soil salt content, followed by stem and leaf, and the effect on flower disc seemed complex.

  6. Potency of Gamma ray, Electric Current and Elicitor Application, as a Novel Practical Technique, to Improve Biomass Production and Glycoside Quality for Digitalis purpurea L. Grown in Sandy Soil Irrigated with Brackish Water

    International Nuclear Information System (INIS)

    Bosila, H.A.; Afifi, L.M.A.; Ahmed, T.E.S.

    2012-01-01

    Digitalis purpurea L seeds were treated before sowing with gamma ray (G:0, 2.5, 5, 7.5 KR, and electric current (E:O, 100, 150, 200 mA) then grown in sandy soil irrigated with brackish water (900 ppm) , in splite-splite plot design for 3 replicat (R) at two subsequent seasons , through surface drip irrigation system. Plants at 4- month old and monthly until before flowering were foliar sprayed with MnSO 4 as abiotic elicitor (M :O, 3 ppm). Biomass/ Feddan, percentage of total glycosides and percentage of bioactive glycosides, digitoxin and gitoxin were quantitated. Statistical analysis for the obtained data revealed that G, E and M achieved significant in biomass yield and its quality traits. Moreover, interactions ; GE, GM, EM and GEM achieved synergistic and significant increment for this traits. At such G dose the trait was increased by increasing E dose and M concentration. Hence, G 2.5, 5,7.5 KR E200 mA M3 ppm achieved significant increment, as percent over that of control, in biomass production / Feddan by 22, 29, 32%, total glycoside by 27, 40, 30%, digitoxin 27, 40, 30% for both first and second seasons, respectively. Whereas, increment for gitoxin were 27, 41, 30% at first season and 26, 38, 30% at second season, respectively. Overall, these finding strongly confirm the reliability of GEM as a novel practical technique for overproduction biomass/Fed. and quality improvement bioactive cardiac glycosides, digitoxin and gitoxin in Digitalis purpurea L.

  7. Effect of seed rate on growth, yield components and yield of mash bean grown under irrigated conditions of arid uplands of Balochistan, Pakistan

    International Nuclear Information System (INIS)

    Aachakzai, A.K.K.; Taran, S.A.

    2011-01-01

    A field experiment was carried out to investigate the effects of six different seed rates viz., 15, 17.5, 20, 22.5, 25 and 27.5 kg ha/sup -1/ on the growth, yield and yield attributes of mash bean Vigna mungo (L.) Hepper). This study was conducted for two consecutive years at the Agriculture Research Institute (ARI) under the existing semi-arid climatic, edaphic and water conditions of Quetta, Balochistan. Results revealed that plant population, pods plant/sup -1/, grain yield plant/sup -1/ and grain yield ha/sup -1/ were significantly (p<0.05 influenced by varying seed rates. However, other mentioned growth and yield attributes did not respond significantly. Statistically and numerically a maximum yield plant/sup -1/ (20.98 g) and yield ha/sup -1/ (3120 kg) were obtained in applied seed at the rate of 20 kg ha/sup -1/. Whereas, the same was obtained for plant population and plant height in applied seed rate of 25 kg ha/sup -1/. However, maximum number of branches plant/sup -1/ (4.22) was received for applied seeds at the rate of 15 kg ha/sup -1/. Therefore, seed at the rate of 20 kg ha/sup -1/ seems optimum which could be due to the most desirable population or planting density in the existing environmental conditions of Quetta. Results further revealed that only plant population plot/sup -1/ (r=0.481), and yield plant/sup -1/ (r=0.569) were significantly and positively correlated with grain yield ha/sup -1/, while all other remaining growth and yield attributes exhibited insignificant association with grain yield ha/sup -1/. Hence these two parameters i.e., planting density and grain yield plant/sup -1/ should be given more consideration while deciding about selection criteria for mash bean under irrigated conditions of arid uplands of Balochistan. (author)

  8. Equipamentos de pulverização aérea e taxas de aplicação de fungicida na cultura do arroz irrigado Spraying equipment and rates of fungicide application in irrigated rice

    Directory of Open Access Journals (Sweden)

    Tânia Bayer

    2011-02-01

    Full Text Available O controle eficiente de doenças na cultura do arroz irrigado depende da seleção correta do equipamento, da taxa de aplicação e da indicação certa do produto químico. O objetivo deste trabalho foi verificar a deposição de gotas na cultura do arroz comparando-se bicos hidráulicos no sistema convencional, eletrostático e atomizador rotativo de disco, em diferentes taxas de aplicação por via aérea; para tanto, foram estudadas a densidade e a penetração de gotas nos estratos médio e inferior, produtividade e rendimento de engenho do arroz. Os tratamentos avaliados foram: bico hidráulico 20 e 30 L ha-1, eletrostático 5 e 10 L ha-1 e atomizador rotativo de disco 6, 10 e 15 L ha-1. Não foram verificadas diferenças de produtividade e os equipamentos bico hidráulico 20 L ha-1 e atomizador rotativo de disco 15 L ha-1 proporcionaram maior rendimento de engenho. Maiores taxas de aplicação usando-se bicos hidráulicos e atomizador rotativo proporcionaram maior penetração e, consequentemente, também maior densidade de gotas nos dois estratos avaliados.The efficient chemical control in irrigated rice depends on the correct selection of equipment, rates of application and correct statement of the chemical product. The objective of this study was to evaluate the hydraulic nozzle equipment, electrostatic system and rotary-disk atomizer for aerial application of fungicides, relating to penetration and density of droplets with application rates and equipment in the middle and lower strata, in addition to the productivity and hulling yield in irrigated rice. The treatments were: nozzle hydraulic 20 and 30 L ha-1, electrostatic system 5 and 10 L ha-1, rotary-disk atomizer 6, 10 and 15 L ha-1. There was no difference in productivity and equipment hydraulic nozzle 20 L ha-1 and rotary-disk atomizer 15 L ha-1 showed a higher hulling yield. On average, higher rates had higher penetration and density in both the evaluated canopy strata.

  9. assessment of cadmium and lead in soil and tomatoes grown

    African Journals Online (AJOL)

    MAHMUD IMAM

    Transfer of Heavy Metals from Soil to Lettuce (Lactuca sativa) grown in irrigated farmlands of ... respectively being the highest elements absorbed by the lettuce samples from the irrigated .... radioactive elements and organic chemicals,.

  10. Cadmium accumulation characteristics of low-cadmium rice (Oryza sativa L.) line and F1 hybrids grown in cadmium-contaminated soils.

    Science.gov (United States)

    Li, Kun; Yu, Haiying; Li, Tingxuan; Chen, Guangdeng; Huang, Fu

    2017-07-01

    Cadmium (Cd) pollution has threatened severely to food safety and human health. A pot experiment and a field experiment were conducted to investigate the difference of Cd accumulation between rice (Oryza sativa L.) lines and F 1 hybrids in Cd-contaminated soils. The adverse effect on biomass of rice lines was greater than that of F 1 hybrids under Cd treatments in the pot experiment. The variations of Cd concentration among rice cultivars in different organs were smaller in stem and leaf, but larger in root and ear. Average proportion of Cd in root of F 1 hybrids was 1.39, 1.39, and 1.16 times higher than those of rice lines at the treatment of 1, 2, and 4 mg Cd kg -1 soil, respectively. Cd concentrations in ear of F 1 hybrids were significantly lower than rice lines with the reduction from 29.24 to 50.59%. Cd concentrations in brown rice of all F 1 hybrids were less than 0.2 mg kg -1 at 1 mg Cd kg -1 soil, in which Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be screened out as cadmium-safe cultivars (CSCs) for being safe even at 2 mg Cd kg -1 soil. C268A/YaHui2816 showed the lowest Cd concentration in root among F 1 hybrids, while Lu98A/YaHui2816 and 5406A/YaHui2816 showed lower capability of Cd translocation from root to shoot under Cd exposure, which eventually caused the lower Cd accumulation in brown rice. The lower level of Cd translocation contributed to reducing the accumulation of Cd in brown rice had been validated by the field experiment. Thus, Lu98A/YaHui2816, 5406A/YaHui2816, and C268A/YaHui2816 could be considered as potential CSCs to cultivate in Cd-contaminated soils (<2 mg Cd kg -1 soil).

  11. Impact of Rice Paddy Areas Decrease on Local Climate over Taiwan

    Science.gov (United States)

    Lo, M. H.; Wen, W. H.; Chen, C. C.

    2014-12-01

    Agricultural irrigation practice is one of the important anthropogenic processes in the land surface modeling. Irrigation can decrease local surface temperature with alternating surface energy partitioning. Rice paddy is the major food crop in Asian monsoon region and rice is grown under flooded conditions during the growing season; hence, the rice paddy can be considered as an open water body, which has more impacts on the surface energy budget than other cropland does. In this study, we explore how the rice paddy area changes affect Taiwan's regional climate from both observational data and numerical modeling exercise. The Weather Research and Forecasting (WRF) model is utilized to explore impacts of rice paddy area changes on the regional climate, and energy and water budget changes. In addition, temperature datasets from six automatic weather stations in the northern Taiwan and two stations in the southern Taiwan are analyzed in this study to explore how the Daily Temperature Range (DTR) changes with the decreased rice paddy areas. Previous studies show that due to the urban heat island effect, aerosol direct and indirect effects, and global warming, the DTR has decreased in the past 4 decades observed from most of the weather stations around Taiwan. However, the declined rice paddy area may increase the DTR with higher Bowen ratio during the daytime. Preliminary results show that DTR is decreased in weather stations near the urban area, but increased in weather stations near fallow areas in the past 20 years. It shows that different land use changes may have opposite impacts on local and regional climate.

  12. Genome wide association mapping of grain arsenic, copper, molybdenum and zinc in rice (Oryza sativa L. grown at four international field sites.

    Directory of Open Access Journals (Sweden)

    Gareth J Norton

    Full Text Available The mineral concentrations in cereals are important for human health, especially for individuals who consume a cereal subsistence diet. A number of elements, such as zinc, are required within the diet, while some elements are toxic to humans, for example arsenic. In this study we carry out genome-wide association (GWA mapping of grain concentrations of arsenic, copper, molybdenum and zinc in brown rice using an established rice diversity panel of ∼ 300 accessions and 36.9 k single nucleotide polymorphisms (SNPs. The study was performed across five environments: one field site in Bangladesh, one in China and two in the US, with one of the US sites repeated over two years. GWA mapping on the whole dataset and on separate subpopulations of rice revealed a large number of loci significantly associated with variation in grain arsenic, copper, molybdenum and zinc. Seventeen of these loci were detected in data obtained from grain cultivated in more than one field location, and six co-localise with previously identified quantitative trait loci. Additionally, a number of candidate genes for the uptake or transport of these elements were located near significantly associated SNPs (within 200 kb, the estimated global linkage disequilibrium previously employed in this rice panel. This analysis highlights a number of genomic regions and candidate genes for further analysis as well as the challenges faced when mapping environmentally-variable traits in a highly genetically structured diversity panel.

  13. Estruturas automáticas para controle de água nos canais em lavoura de arroz irrigado Automatic structures for water control in channels on irrigated rice crops

    Directory of Open Access Journals (Sweden)

    Luís G. H. do Amaral

    2005-04-01

    Full Text Available O Rio Grande do Sul apresenta a maior área irrigada do Brasil, devido principalmente à lavoura de arroz irrigado por inundação. Um dos fatores que contribuem para reduzir a eficiência de irrigação nessas lavouras é o baixo grau de controle exercido pelas estruturas de distribuição de água. Os objetivos deste trabalho foram projetar e construir dois protótipos de estruturas hidráulicas para controle automático de vazão em canais de irrigação e comparar sua sensibilidade de controle de vazão com a sensibilidade de duas comportas fixas. Os protótipos construídos - uma comporta hidromecânica automática e um regulador automático de vazão - foram instalados à entrada de um canal secundário, juntamente com uma comporta-gaveta e uma comporta-vertedor, que são as estruturas mais utilizadas para controle de vazão no RS. Provocou-se uma variação de 0,20 m na altura da lâmina de água a montante, determinando-se a vazão em cada estrutura. A menor variação de vazão com a alteração da lâmina foi de 5,6%, obtida com o regulador automático de vazão, seguido da comporta-gaveta com 23,7%, da comporta hidromecânica com 30,5%, e da comporta vertedor com 1.177,2%.In Brazil, the State that presents the largest extension of irrigated lands is Rio Grande do Sul, mainly due to rice that grows under flooded conditions. One of the factors that contribute to decrease the efficiency of irrigation is the low degree of control obtained with the structures used on water distribution. The objectives of this work were to design and build two hydraulic structures for automatic flow control on irrigation channels, and to compare the flow control sensitivity of the built prototypes with two types of gates that are widely used in the rice fields at the Rio Grande do Sul State. The constructed prototypes - a hydro-mechanical gate and an automatic flow regulator - were installed at the entrance of a secondary channel, next to a sluice gate and

  14. Scheduling irrigation for jujube ( Ziziphus jujuba Mill. ) | Zhang ...

    African Journals Online (AJOL)

    This study was performed to select suitable indicator for scheduling the irrigation of jujube (Ziziphus jujuba Mill.) grown in the Loess Plateau. The relationships between plant-based indicators and soil matrix potential as well as meteorological factors of jujube under deficit irrigation compared with well irrigation were ...

  15. Impacts of integrated nutrient management on methane emission, global warming potential and carbon storage capacity in rice grown in a northeast India soil.

    Science.gov (United States)

    Bharali, Ashmita; Baruah, Kushal Kumar; Baruah, Sunitee Gohain; Bhattacharyya, Pradip

    2018-02-01

    Rice soil is a source of emission of two major greenhouse gases (methane (CH 4 ) and nitrous oxide (N 2 O)) and a sink of carbon dioxide (CO 2 ). The effect of inorganic fertilizers in combination with various organics (cow dung, green manure (Sesbania aculeata) Azolla compost, rice husk) on CH 4 emission, global warming potential, and soil carbon storage along with crop productivity were studied at university farm under field conditions. The experiment was conducted in a randomized block design for 2 years in a monsoon rice (cv. Ranjit) ecosystem (June-November, 2014 and 2015). Combined application of inorganic (NPK) with Sesbania aculeata resulted in high global warming potential (GWP) of 887.4 kg CO 2 ha -1 and low GWP of 540.6 kg CO 2 ha -1 was recorded from inorganic fertilizer applied field. Irrespective of the type of organic amendments, flag leaf photosynthesis of the rice crop increased over NPK application (control). There was an increase in CH 4 emission from the organic amended fields compared to NPK alone. The combined application of NPK and Azolla compost was effective in the buildup of soil carbon (16.93 g kg -1 ) and capacity of soil carbon storage (28.1 Mg C ha -1 ) with high carbon efficiency ratio (16.9). Azolla compost application along with NPK recorded 15.66% higher CH 4 emission with 27.43% yield increment over control. Azolla compost application significantly enhanced carbon storage of soil and improved the yielding ability of grain (6.55 Mg ha -1 ) over other treatments.

  16. Influence of plant species and environmental conditions on epiphytic and endophytic pink-pigmented facultative methylotrophic bacterial populations associated with field-grown rice cultivars.

    Science.gov (United States)

    Madhaiyan, Munusamy; Poonguzhali, Selvaraj; Sa, Tongmin

    2007-10-01

    The total methylotrophic population associated with rice plants from different cultivars was enumerated at three different stages: vegetative, flowering, and harvesting. The bacterial population in the leaf, rhizosphere soil, endophytic in the stem and roots, and epiphytic in the florets and grains were determined from four rice cultivars, Il-mi, Nam-pyeoung, O-dae, and Dong-jin, sampled from three different field sites. The methylotrophic bacteria isolated on AMS media containing 0.5% methanol as the sole carbon source uniformly showed three distinct morphologies, which were recorded as separate groups and their distribution among the various samples was determined using the ecophysiological index. The growth stage at the time of sampling had a more significant effect on the methylotrophic population and their distribution than the field site or cultivar. A similar effect was also observed for the PPFMs, where their population in different plant parts increased from V10 to R4 and then decreased towards stage R9. A canonical discriminant analysis of the PPFM population from different parts of rice showed clear variations among the cultivars, sampled sites, and growth stages, although the variations were more prominent among the growth stages.

  17. Declining groundwater level caused by irrigation to row crops in the Lower Mississippi River Basin, Current Situation and Trends

    Science.gov (United States)

    Feng, G.; Gao, F.; Ouyang, Y.

    2017-12-01

    The Mississippi River is North America's largest river and the second largest watershed in the world. It flows over 3,700 km through America's heartland to the Gulf of Mexico. Over 3 million hectares in the Lower Mississippi River Basin represent irrigated cropland and 90 percent of those lands currently rely on the groundwater supply. The primary crops grown in this region are soybean, corn, cotton, and rice. Increased water withdrawals for irrigating those crops and stagnant recharging jeopardize the long-term availability of the aquifer and place irrigation agriculture in the region on an unsustainable path. The objectives of this study were to: 1) analyze the current groundwater level in the Lower Mississippi River Basin based on the water table depth observed by Yazoo Mississippi Delta Joint Water Management District from 2000 and 2016; 2) determine trends of change in groundwater level under conventional and groundwater saving irrigation management practices (ET or soil moisture based full irrigation scheduling using all groundwater or different percentages of ground and surface water). The coupled SWAT and MODFLOW model was applied to investigate the trends. Observed results showed that the groundwater level has declined from 33 to 26 m at an annual decrease rate of 0.4 m in the past 17 years. Simulated results revealed that the groundwater storage was decreased by 26 cm/month due to irrigation in crop season. It is promising that the groundwater storage was increased by 23 cm/month, sometimes even 60 cm/month in crop off-growing season because of recharge from rainfall. Our results suggest that alternative ET or soil moisture based groundwater saving irrigation scheduling with conjunctive use of surface water is a sustainable practice for irrigated agriculture in in the Lower Mississippi River Basin.

  18. Atributos químicos do solo afetado pelo manejo da água e do fertilizante potássico na cultura de arroz irrigado Chemical properties of soil affected by water and potassium fertilization management in irrigated rice

    Directory of Open Access Journals (Sweden)

    Alberto B. dos Santos

    2002-04-01

    Full Text Available O desenvolvimento das culturas nas várzeas é extremamente influenciado pelo manejo destas, devido aos atributos químicos e físico-hídricos que elas possuem. O decréscimo na produtividade, verificado no monocultivo contínuo de arroz (Oryza sativa L. irrigado, pode estar relacionado à redução na fertilidade do solo, em decorrência da lixiviação de nutrientes. Com o objetivo de se avaliar os efeitos de manejo da água (MA1 - inundação contínua e MA2 - inundação intermitente seguida de contínua e do fertilizante potássico (K1 - na semeadura; K2 - adubação parcelada e K3 - meia dosagem parcelada na cultura de arroz irrigado sobre alguns atributos químicos de um solo Gley Pouco Húmico, foram conduzidos experimentos durante três anos consecutivos. Na inundação contínua ocorre maior lixiviação de cálcio e de potássio, teor de fósforo no solo e saturação por alumínio e menor pH na camada superficial do solo em relação à inundação intermitente, além de aumento do teor de potássio e do pH e diminuição de saturação por alumínio em profundidade. A inundação intermitente e o parcelamento do potássio podem contribuir na redução das perdas de nutrientes em solos de várzea que apresentam percolação excessiva. Alguns atributos químicos do solo podem ser melhorados através do manejo adequado da cultura do arroz irrigado, envolvendo manejo da água e do fertilizante potássico.Crop performance in lowland soils is influenced by management practices due to change in physico-chemical properties. Grain yield decrease in continuous monoculture of irrigated rice (Oryza sativa L. may be associated with decrease in soil fertility due to leaching of nutrients. The objective of this study was to evaluate effect of water management (WM1 - continuous flooding, and WM2 - intermittent flooding followed by continuous flooding and potassium fertilization (K1 - at sowing; K2 - fractional application, and K3 - fractional

  19. A preliminary study on the uptake of radioiodine by rice plants from soil

    International Nuclear Information System (INIS)

    Uchida, Shigeo; Muramatsu, Yasuyuki; Sumiya, Misako; Ohmomo, Yoichiro; Yamaguchi, Shuho.

    1989-01-01

    In an atmospheric discharge of radioiodines, direct deposition of the nuclides onto leaf surface must be the most significant pathway from the environment to man. However, 129 I reaches man through several pathways because of its long half life of 1.6 x 10 7 years. Root uptake of 129 I is one of the most important pathways of this nuclide. In Japan, rice is thought to be the most critical crop on the pathway. In this paper, uptake of radioiodine from irrigation water by rice plant was investigated. Rice plants, Oryza sativa cv. Nihonbare, were grown under flooded condition in Wagner pots containing soil collected in Tokai-mura. Iodine-131 was added as a tracer into the surface water in the pots at three different growing stages, heading, dough-ripe and yellow-ripe stages, respectively, and the plants were cultivated until the harvest time in a plant growth chamber. At the harvest time, concentration of 131 I in each organ of rice plant was measured with a NaI scintillation counter. The profile of 131 I in the soil was also investigated. The results obtained are as follows; (1) Activities of 131 I in leaf blade and sheath of lower part were generally higher than those of upper part. Compared to the 131 I activity of the flag leaf, the ratios of the activity in rachis-branch, hull and brown rice were 1.0-0.5, 0.1 and 1-5 x 10 -3 , respectively. These may suggest that iodine taken up by the roots scarcely re-translocated into rice. (2) Ratio of 131 I in brown rice and hull was about 1 : 4. (3) Activity ratio ('concentration of 131 I in brown rice'/'average concentration of that in the soil' during 6 days uptake experiment.) was 4-5 x 10 -4 . (author)

  20. Systemic induced tolerance against root-knot nematodes in rice

    African Journals Online (AJOL)

    user

    Rice plantlets were randomly grown in laboratory, sprayed with hormones and riboflavin .... between riboflavin, SA, JA and ET pathways in rice-nematodes interaction, ..... oxidative damage caused by aging as well as biotic and abiotic stress.

  1. REMOTE-SENSING-BASED BIOPHYSICAL MODELS FOR ESTIMATING LAI OF IRRIGATED CROPS IN MURRY DARLING BASIN

    Directory of Open Access Journals (Sweden)

    I. Wittamperuma

    2012-07-01

    Full Text Available Remote sensing is a rapid and reliable method for estimating crop growth data from individual plant to crops in irrigated agriculture ecosystem. The LAI is one of the important biophysical parameter for determining vegetation health, biomass, photosynthesis and evapotranspiration (ET for the modelling of crop yield and water productivity. Ground measurement of this parameter is tedious and time-consuming due to heterogeneity across the landscape over time and space. This study deals with the development of remote-sensing based empirical relationships for the estimation of ground-based LAI (LAIG using NDVI, modelled with and without atmospheric correction models for three irrigated crops (corn, wheat and rice grown in irrigated farms within Coleambally Irrigation Area (CIA which is located in southern Murray Darling basin, NSW in Australia. Extensive ground truthing campaigns were carried out to measure crop growth and to collect field samples of LAI using LAI- 2000 Plant Canopy Analyser and reflectance using CROPSCAN Multi Spectral Radiometer at several farms within the CIA. A Set of 12 cloud free Landsat 5 TM satellite images for the period of 2010-11 were downloaded and regression analysis was carried out to analyse the co-relationships between satellite and ground measured reflectance and to check the reliability of data sets for the crops. Among all the developed regression relationships between LAI and NDVI, the atmospheric correction process has significantly improved the relationship between LAI and NDVI for Landsat 5 TM images. The regression analysis also shows strong correlations for corn and wheat but weak correlations for rice which is currently being investigated.

  2. Elemental Composition of Two Rice Cultivars under Potentially Toxic an Aquept and Aquent

    Directory of Open Access Journals (Sweden)

    Adesola Olutayo OLALEYE

    2009-12-01

    Full Text Available Iron toxicity is a major nutrient disorder affecting rice production of wetland rice in the irrigated and rainfed ecosystem in West Africa sub-region. Little attention has been paid to evaluating nutrient contents of rice cultivars grown on such soils and their relationship to the iron toxicity scores, grain yield and dry matter yields. A pot experiment was conducted on two potentially Fe-toxic soils (Aeric Fluvaquent and Aeric Tropaquept. The experiment was a 2 x 2 x 4 factorial experiment with three replicates in arranged in a randomized fashion. The factors were two soil types, two rice cultivars (ITA 212 and tolerant (Suakoko 8 and four Fe 2+ levels (control, 1000, 3000 and 4000 mg L-1. The result showed that for both susceptible cultivar (ITA 212 and the relatively tolerant (Suakoko 8 cultivar, little or no differences were observed in their elemental composition with regards to micro and macro-nutrients. For the susceptible cultivar, results showed that none of the tissue nutrients significantly relates to iron toxicity scores (ITS, grain yield and dry matter yield on both soil types. However, for the tolerant cultivar, ITS was observed to be significantly related to tissue K and P contents on the two soil types respectively. Tissue Ca and Mg were observed to be significantly related to the dry matter yield (DMY on Aeric Tropquept. It could be concluded that for these rice cultivars grown on two potentially Fe-toxic soils, different tissue nutrients may trigger the manifestation of bronzing or yellowing symptoms of rice cultivars.

  3. Desempenho de genótipos de arroz irrigado cultivados no sistema pré-germinado com inundação contínua Performance of irrigated rice genotypes on a pre-germinated system with continuous flooding

    Directory of Open Access Journals (Sweden)

    Enio Marchezan

    2004-10-01

    days after seeding in order to improve plant establishment. This practice therefore, causes water and nutrient losses and weeds reinfestation. The permanence of water in the field could minimize these problems. Experiments were conducted during the years of 2000/01 till 2002/03 aiming to evaluate the performance of permanent irrigated rice genotypes under flooding, specially for plant lodging, a limiting factor of this management system. The experiments were conducted on a lowland area in a Haplaqualf soil and the treatments were 8, 12 and 15 genotypes in the first, second, and third years, respectively. In the year 1 the mean rice yield was 7279kg ha-1 and IRGA 1572-11-1F-1-4-4 (8279kg ha-1 the most productive genotype. Lodging percentage varied between 0 and 60% and for most treatments in the range from to 0-20%. All genotypes presented some degree of lodging, except El Paso L 144. In the year 2 the mean rice yield was 8492kg ha-1 and the most productive was BRS-Pelota (9282kg ha-1, and no lodging occurred among the tested genotypes. In the year 3, the mean yield was 6202kg ha-1 and was related to a high percentage of the lodging, due to climatic events during seed filling. It was observed that rice yield can be high under permanent flooding but lodging is a limiting factor depending on genotype and environmental conditions.

  4. Comparative study of irrigation water use and groundwater recharge under various irrigation schemes in an agricultural region, central Taiwan

    Science.gov (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

    2016-04-01

    The risk of rice production has increased notably due to climate change in Taiwan. To respond to growing agricultural water shortage without affecting normal food production in the future, the application of water-saving irrigation will be a substantial resolution. However, the adoption of water-saving irrigation may result in the reducing of groundwater recharge because continuous flooding in the paddy fields could be regarded as an important source for groundwater recharge. The aim of this study was to evaluate the irrigation water-saving benefit and groundwater recharge deficit when adopting the System of Rice Intensification, known as SRI methodology, in the Choushui River alluvial fan (the largest groundwater pumping and the most important rice-cropping region in central Taiwan). The three-dimensional finite element groundwater model, FEMWATER, was applied to simulate the infiltration process and groundwater recharge under SRI methodology and traditional irrigation schemes including continuous irrigation, and rotational irrigation in two rice-crop periods with hydro-climatic data of 2013. The irrigation water use was then calculated by water balance. The results showed that groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reduced 3.6% and 1.6% in the first crop period, and reduced 3.2% and 1.6% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. However, the SRI methodology achieved notably water-saving benefit compared to the disadvantage of reducing the groundwater recharge amount. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 37% and 20% of irrigation water in the first crop period, and saving 53% and 35% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. Therefore, the amount of groundwater pumping for

  5. Fine-mapping of qRL6.1, a major QTL for root length of rice seedlings grown under a wide range of NH4+ concentrations in hydroponic conditions

    Science.gov (United States)

    Tamura, Wataru; Ebitani, Takeshi; Yano, Masahiro; Sato, Tadashi; Yamaya, Tomoyuki

    2010-01-01

    Root system development is an important target for improving yield in cereal crops. Active root systems that can take up nutrients more efficiently are essential for enhancing grain yield. In this study, we attempted to identify quantitative trait loci (QTL) involved in root system development by measuring root length of rice seedlings grown in hydroponic culture. Reliable growth conditions for estimating the root length were first established to renew nutrient solutions daily and supply NH4+ as a single nitrogen source. Thirty-eight chromosome segment substitution lines derived from a cross between ‘Koshihikari’, a japonica variety, and ‘Kasalath’, an indica variety, were used to detect QTL for seminal root length of seedlings grown in 5 or 500 μM NH4+. Eight chromosomal regions were found to be involved in root elongation. Among them, the most effective QTL was detected on a ‘Kasalath’ segment of SL-218, which was localized to the long-arm of chromosome 6. The ‘Kasalath’ allele at this QTL, qRL6.1, greatly promoted root elongation under all NH4+ concentrations tested. The genetic effect of this QTL was confirmed by analysis of the near-isogenic line (NIL) qRL6.1. The seminal root length of the NIL was 13.5–21.1% longer than that of ‘Koshihikari’ under different NH4+ concentrations. Toward our goal of applying qRL6.1 in a molecular breeding program to enhance rice yield, a candidate genomic region of qRL6.1 was delimited within a 337 kb region in the ‘Nipponbare’ genome by means of progeny testing of F2 plants/F3 lines derived from a cross between SL-218 and ‘Koshihikari’. Electronic supplementary material The online version of this article (doi:10.1007/s00122-010-1328-3) contains supplementary material, which is available to authorized users. PMID:20390245

  6. Evaluation of Heavy Metals Contamination from Environment to Food Matrix by TXRF: The Case of Rice and Rice Husk

    Directory of Open Access Journals (Sweden)

    Fabjola Bilo

    2015-01-01

    Full Text Available This paper is devoted to the chemical analysis of contaminated soils of India and the rice grown in the same area. Total reflection X-ray fluorescence spectroscopy is a well-established technique for elemental chemical analysis of environmental samples, and it can be a useful tool to assess food safety. Metals uptake in rice crop grown in soils from different areas was studied. In this work soil, rice husk and rice samples were analyzed after complete solubilization of samples by microwave acid digestion. Heavy metals concentration detected in rice samples decreases in the following order: Mn > Zn > Cu > Ni > Pb > Cr. The metal content in rice husk was higher than in rice. This study suggests, for the first time, a possible role of heavy metals filter played by rice husk. The knowledge of metals sequestration capability of rice husk may promote some new management practices for rice cultivation to preserve it from pollution.

  7. Impact of Organic Amendments on Global Warming Potential of Diversified Tropical Rice Rotation Systems

    Science.gov (United States)

    Janz, B.; Weller, S.; Kraus, D.; Wassmann, R.; Butterbach-Bahl, K.; Ralf, K.

    2017-12-01

    Paddy rice cultivation is increasingly challenged by irrigation water scarcity, which is forcing farmers to change traditional rice cultivation from flooded double-rice systems to the introduction of well-aerated upland crops during dry season. Emissions of methane (CH4) are expected to decrease, while there is a risk of increasing emissions of nitrous oxide (N2O) and decreasing soil organic carbon (SOC) stocks through volatilization in the form of carbon dioxide (CO2). We present a unique dataset of long-term continuous greenhouse gas emission measurements (CH4 and N2O) in the Philippines to assess global warming potentials (GWP) of diversified rice crop rotations including different field management practices such as straw residue application and legume intercropping. Since 2012, more than four years of CH4 and N2O emissions in double-rice cropping (R-R) and paddy rice rotations diversified with either maize (R-M) or aerobic rice (R-A) during dry season have been collected. Introduction of upland crops reduced irrigation water use and CH4 emissions by 66-81% and 95-99%, respectively. Although dry season N2O emissions increased twice- to threefold in the diversified systems, the strong reduction of CH4 led to a significantly lower annual GWP (CH4 + N2O) as compared to the traditional R-R system. Diversified crop management practices were first implemented during land-preparation for dry season 2015 where i) 6 t/ha rice straw was returned to the field and ii) mungbean was grown as a cover-crop between dry and wet season in addition to rice straw application. The input of organic material (straw and mungbean) led to higher substrate availability for methanogens during the following season. Therefore, GWP was 9-39% higher following straw incorporation than the control treatment. This increase was mainly driven by additional CH4 emissions. Even more, mungbean intercropping further increased GWPs, whereby the increment was highest in R-R rotation (88%) and lowest in R

  8. HARVEST TIME AND PHYSIOLOGIC QUALITY OF SEEDS IN IRRIGATED RICE (Oryza sativa cv. BRS RORAIMA ÉPOCA DE COLHEITA E QUALIDADE FISIOLÓGICA DE SEMENTES EM ARROZ IRRIGADO (Oryza sativa cv. BRS RORAIMA

    Directory of Open Access Journals (Sweden)

    Oscar José Smiderle

    2008-09-01

    Full Text Available

    Harvest time is one of most important factors influencing rice seed characteristics for purpose of either planting or milling. With the objective to determine a proper harvesting  time, irrigated rice seeds of cultivar BRS Roraima were harvested at 15, 22, 29, 36, 43 and 50 days after flowering (DAF, and assessed according to humidity, viability, dry mass of 1,000 seeds, whole grain yield, productivity and storability. Seeds harvested 29 DAF showed high quality and its productivity was equivalent to the subsequent periods. Seeds harvested 50 DAF showed good performance, except for whole grain yield. Harvests 15 and 22 DAF were unsuitable, reducing the physiologic quality of seeds, mill efficiency and high initial humidity. The adequate harvest time for cultivar BRS Roraima is between 29 and 43 DAF, when seeds present higher yield, dry mass, whole grain yield, physiologic quality and storability.

    KEY-WORDS: Physiologic quality; whole grain; humidity.

    A época de colheita é um dos fatores mais importantes que influenciam as características da semente de arroz, seja para semeadura ou para consumo. Com o objetivo de determinar a época adequada de colheita de arroz irrigado, para a cultivar BRS Roraima, sementes foram colhidas aos 15, 22, 29, 36, 43 e 50 dias após o florescimento (DAF e avaliadas quanto à umidade, viabilidade, massa seca de 1.000 sementes, rendimento de grãos inteiros, produtividade e armazenabilidade. As sementes colhidas aos 29 DAF

  9. Chemical composition and structural changes of irrigated rice during storageComposição química e alterações estruturais do arroz irrigado durante o armazenamento

    Directory of Open Access Journals (Sweden)

    Tiago André Kaminski

    2013-06-01

    Full Text Available The effect storage time at different temperatures (0.5, 20 and 35 °C was periodically evaluated in regard to the chemical composition, elongation capacity and viscoamylographic properties of three irrigated rice varieties (BR-IRGA 410, IRGA 416 and IRGA 417 during 180 days. The alterations in the components of the polished grains were significant (P O efeito do tempo de armazenamento em diferentes temperaturas (0,5; 20 e 35°C foi avaliado sobre a composição química, capacidade de elongação e propriedades viscoamilográficas de três variedades de arroz irrigado (BR-IRGA 410, IRGA 416 e IRGA 417, durante 180 dias. As alterações nos componentes dos grãos polidos foram significativas (P<0,05 para o teor de matéria mineral, compostos fenólicos, amilose e amido resistente, com incrementos nos valores encontrados, principalmente em maiores períodos e temperaturas de armazenamento. As variáveis do experimento (variedade do arroz irrigado, tempo e temperatura do armazenamento influenciaram significativamente (P<0,01 nos parâmetros de elongação dos grãos, com aumentos expressivos durante o armazenamento a 35°C e nas propriedades viscoamilográficas, ou seja, observou-se maior viscosidade, resistência à quebra e retrogradação para as amostras com maior teor de amilose e mantidas a 35°C durante o armazenamento. As alterações nos componentes dos grãos, quando significativas (P<0,05, foram bastante discretas e não diretamente relacionadas às significativas alterações (P<0,01 de elongação e viscosidade. A temperatura se mostrou uma variável de grande influência no processo de envelhecimento do arroz, sugerindo a possibilidade do armazenamento deste cereal em maiores temperaturas para conferir qualidade culinária em menor tempo de armazenamento.

  10. Pore Water Arsenic Dynamics in Rice Paddies Under Projected Future Climates

    Science.gov (United States)

    Plaganas, M.; Wang, T.; Muehe, E. M.; Fendorf, S. E.

    2016-12-01

    Rice is one of the staple crops in the world, with 50% of the global population eating rice daily. Many rice-producing regions of the world are irrigated with groundwater contaminated with arsenic (As), and in particular South and Southeast Asia, where geogenic As is leached into the groundwater. Use of groundwater pervasively high in As leads to subsequent accumulation in paddy soils. Arsenic, a toxic metalloid, also decreases rice productivity and further jeopardizes food security. Hence, rice agriculture is concerned with its productivity in a climate change impacted future and the particular impacts of arsenic on yields. However, past studies do not address the prevalence of As in paddy soils or its fate in the rhizosphere and ultimate impact on the plant. The objective of our study was to determine changes in pore water As dynamics in the rhizosphere of rice plants grown on As-contaminated paddy soil under climate conditions projected for the end of the century. In order to address this objective, we designed greenhouse chambers with today's climate and projected climate conditions for the year 2100, specifically 5°C increase in temperature and doubled concentration of atmospheric CO2. We hypothesize that the effects of climate change with these conditions will increase the mobility of As in the rhizosphere, and thus, decrease rice growth in As-bearing paddies more than, so far, expected. We examined pore water geochemistry including pH and As concentrations, and correlate that to the height of the plants. Furthermore, the dynamics of other elements in the pore water such as carbon, iron, sulfur, manganese, and silica are further evaluated for their effects on rice growth. Arsenic will have an impact on rice production and conditions induced by future climatic conditions need to be considered for food security. Considering that climate change will decrease the global agricultural output, we should urgently consider adapting our agricultural practices to aid

  11. Exploring options for water savings in lowland rice using a modelling approach

    NARCIS (Netherlands)

    Belder, P.; Bouman, B.A.M.; Spiertz, J.H.J.

    2007-01-01

    Water-saving irrigation regimes are needed to deal with a reduced availability of water for rice production. Two important water-saving technologies at field scale are alternately submerged¿nonsubmerged (SNS) and flush irrigated (FI) rice. SNS allows dry periods between submerged soil conditions,

  12. Rendimento do arroz e manejo da irrigação e da palha de azevém no sistema mix de pré-germinado Rice yield and management of irrigation and ryegrass straw on flooded rice in no tillage and water seed system

    Directory of Open Access Journals (Sweden)

    Eduardo González Pinto

    2003-04-01

    limiting factor in many agricultural areas, when high productivity is the objective. Alternative system of crop cultivation using no tillage on flooded water seed system can be used to minimize the problem. Although this system has technical and economical advantages on the production chain, especially on red rice control, anaerobic process of ryegrass straw decomposition may produce toxic substances to rice plants establishment. The objective of this work was to evaluate the effect of different water irrigation management and the amount of ryegrass straw on grain yield and yield components on paddy rice cultivated. The experiment was conducted in greenhouse, during the 1998/99 crop growing season, on Hidromorphy Planosoil, sandy Eutrophic, soil mapping unit "Vacacaí", over ryegrass crop residue at the Federal University of Santa Maria, Santa Maria, RS. The rice cultivar IRGA 417 was used. A completely randomized design factorial (3x3, three water management (with neither vertical nor surface in-out water flow over the soil, with drainage and surface water flow and three amount of ryegrass straw (0.0 t ha-1, 3.43 t ha-1 and 6.86 t ha-1. The data demonstrated that a permanent flooding with neither vertical nor surface in-out water flow reduce dry matter above ground and grain yield when compared to the treatments with drainage and surface in-out water flow. Increasing the amount of ryegrass straw on the no-tillage water seed system, with neither vertical nor surface in-out water flow, on the flooded water the grain yield is reduced.

  13. Trash-polluted irrigation: characteristics and impact on agriculture

    Science.gov (United States)

    Sulaeman, D.; Arif, SS; Sudarmadji

    2018-04-01

    Trash pollution has been a problem in sustainable water resources management. Trash pollutes not only rivers, lakes and seas, but also irrigation canals and rice fields. This study aimed to identify the characteristics of solid waste (type, time of occurrence and sources of trash) and its impact on agriculture. The study was conducted in four irrigation areas, namely Gamping, Merdiko, Nglaren and Karangploso in Bantul District, Yogyakarta Special Region. We applied the Irrigation Rapid Trash Assessment (IRTA) as our field survey instrument. The results showed that trash was found throughout irrigation canals and rice fields, and the occurrence was influenced by water flow, time and farmer activities. The irrigation was dominantly polluted by plastic trash (52.2%), biodegradable waste (17.91%) and miscellaneous trash (12.3%). The IRTA score showed that Gamping Irrigation Area was at marginal condition, bearing a high risk of disturbing the operation and maintenance of the irrigation canals as well as farmers’ health. Trash in irrigation also generated technical impact of the irrigation operation and maintenance, environmental quality, and social life. This research also offered environmental policy integration approach and water-garbage governance approach as an alternative solution to manage water resources and agriculture in a sustainable manner, under the pressure of increasing amount of trash.

  14. Effect of water management, tillage options and phosphorus status on arsenic uptake in rice.

    Science.gov (United States)

    Talukder, A S M H M; Meisner, C A; Sarkar, M A R; Islam, M S

    2011-05-01

    High arsenic (As) concentrations in soil may lead to elevated concentrations of arsenic in agricultural products. Field experiments were conducted to examine the effects of water management (WM) and Phosphorus (P) rates on As uptake, rice growth, yield and yield attributes of winter (boro) and monsoon (aman) rice in an As contaminated soil-water at Gobindagonj, Gaibandha, Bangladesh in 2004 and 2005. Significantly, the highest average grain yields (6.88±0.07 t ha(-1) in boro 6.38±0.06 t ha(-1) in aman) were recorded in permanent raised bed (PRB; aerobic WM: Eh=+360 mV) plus 100% P amendment. There was a 12% yield increase over conventional till on flat (CTF; anaerobic WM: Eh=-56 mV) at the same P level. In boro, the As content in grain and As content in straw were about 3 and 6 times higher in CTF compared to PRB, respectively. The highest total As content (0.646±0.01 ppm in grain and 10.93±0.19 ppm in straw) was recorded under CTF, and the lowest total As content (0.247±0.01 and 1.554±0.09 ppm in grain and straw, respectively) was recorded under PRB (aerobic WM). The results suggest that grain and straw As are closely associated in boro rice. The furrow irrigation approach of the PRB treatments consistently reduced irrigation input by 29-31% for boro and 27-30% for aman rice relative to CTF treatments in 2004 and 2005, respectively, thus reducing the amount of As added to the soil from the As-contaminated irrigation water. Yearly, 30% less As was deposited to the soil compared to CTF system through irrigation water during boro season. High As concentrations in grain and straw in rice grown using CTF in the farmers' field, and the fact that using PRB reduced grain As concentrations to value less than half of the proposed food hygiene standard. Copyright © 2010 Elsevier Inc. All rights reserved.

  15. Multisensor Capacitance Probes for Simultaneously Monitoring Rice Field Soil-Water- Crop-Ambient Conditions.

    Science.gov (United States)

    Brinkhoff, James; Hornbuckle, John; Dowling, Thomas

    2017-12-26

    Multisensor capacitance probes (MCPs) have traditionally been used for soil moisture monitoring and irrigation scheduling. This paper presents a new application of these probes, namely the simultaneous monitoring of ponded water level, soil moisture, and temperature profile, conditions which are particularly important for rice crops in temperate growing regions and for rice grown with prolonged periods of drying. WiFi-based loggers are used to concurrently collect the data from the MCPs and ultrasonic distance sensors (giving an independent reading of water depth). Models are fit to MCP water depth vs volumetric water content (VWC) characteristics from laboratory measurements, variability from probe-to-probe is assessed, and the methodology is verified using measurements from a rice field throughout a growing season. The root-mean-squared error of the water depth calculated from MCP VWC over the rice growing season was 6.6 mm. MCPs are used to simultaneously monitor ponded water depth, soil moisture content when ponded water is drained, and temperatures in root, water, crop and ambient zones. The insulation effect of ponded water against cold-temperature effects is demonstrated with low and high water levels. The developed approach offers advantages in gaining the full soil-plant-atmosphere continuum in a single robust sensor.

  16. Rice grown in nutrient solution with doses of manganese and silicon Arroz cultivado em solução nutritiva com doses de manganês e silício

    Directory of Open Access Journals (Sweden)

    Luiz Antônio Zanão Júnior

    2010-10-01

    Full Text Available Although silicon is not recognized as a nutrient, it may benefit rice plants and may alleviate the Mn toxicity in some plant species. The dry matter yield (root, leaf, sheaths and leaf blade and plant architecture (angle of leaf insertion and leaf arc were evaluated in rice plants grown in nutrient solutions with three Mn doses, with and without Si addition. The treatments were arranged in a 2 x 3 factorial [with and without (2 mmol L-1 Si; three Mn doses (0.5; 2.5 and 10 µmol L-1], in a randomized block design with 4 replications. The experimental unit was a 4 L plastic vase with 4 rice (Metica-1 cultivar plants. Thirty nine days after keeping the seedlings in the nutrient solution the plant dry matter yield was determined; the angle of leaf insertion in the sheath and the leaf arc were measured; and the Si and Mn concentrations in roots, sheaths and leaves were determined. The analysis of variance (F test at 5 and 1 % levels and the regression analysis (for testing plant response to Mn with the Si treatments were performed. The Si added to the nutrient solution increased the dry matter yield of roots, sheaths and leaf blades and also decreased the angle of leaf blade insertion into the sheath and the foliar arc in the rice plant. Additionally, it ameliorated the rice plant architecture which allowed an increase in the dry matter yield. Similarly, the addition of Mn to the solution improved the architecture of the rice plants with gain in dry matter yield. As Si was added to the nutrient solution, the concentration of Mn in leaves decreased and in roots increased thus alleviating the toxic effects of Mn on the plants.O silício destaca-se por exercer vários benefícios para a cultura do arroz, apesar de não ser considerado um nutriente. Um desses benefícios é que ele pode amenizar a toxidez causada por Mn em algumas espécies de plantas. Objetivou-se com este trabalho avaliar a produção de matéria seca (raízes, bainhas e limbo foliar e

  17. Developing selection protocols for weed competitiveness in aerobic rice

    NARCIS (Netherlands)

    Zhao, D.L.; Atlin, G.N.; Bastiaans, L.; Spiertz, J.H.J.

    2006-01-01

    Aerobic rice production systems, wherein rice is dry-sown in non-puddled soil and grown as an upland crop, offer large water savings but are subject to severe weed infestation. Weed-competitive cultivars will be critical to the adoption of aerobic rice production by farmers. Breeding

  18. Physical and Chemical Properties of Some Selected Rice Varieties

    African Journals Online (AJOL)

    User

    Physical and chemical properties of nine rice varieties grown and processed in Ebonyi .... Therefore, one tonne of a slender variety of rice will need more storage space than the ..... during washing and boiling of milled rice Starch 36:386-390.

  19. Peanut canopy temperature and NDVI response to varying irrigation rates

    Science.gov (United States)

    Variable rate irrigation (VRI) systems have the potential to conserve water by spatially allocating limited water resources. In this study, peanut was grown under a VRI system to evaluate the impact of differential irrigation rates on peanut yield. Additionally, we evaluated the impact of differenti...

  20. A Mitigation Approach to Alleviate Arsenic Accumulation in Rice through Balanced Fertilization

    International Nuclear Information System (INIS)

    Huq, S.M.I.; Sultana, S.; Chakraborty, G.; Chowdhury, M.T.A.

    2011-01-01

    Pot experiments with boro and aman season rice on the same soils treated with arsenic contaminated irrigation water and using balanced fertilizer or not revealed that balance fertilization could be a strategy to mitigate arsenic accumulation in rice grain. The study also revealed that there is a carryover effect of As applied through irrigation in the boro season to the subsequent aman season rice. This carryover effect too, could be minimized with balanced fertilization.

  1. A Mitigation Approach to Alleviate Arsenic Accumulation in Rice through Balanced Fertilization

    Directory of Open Access Journals (Sweden)

    S. M. Imamul Huq

    2011-01-01

    Full Text Available Pot experiments with boro and aman season rice on the same soils treated with arsenic contaminated irrigation water and using balanced fertilizer or not revealed that balance fertilization could be a strategy to mitigate arsenic accumulation in rice grain. The study also revealed that there is a carryover effect of As applied through irrigation in the boro season to the subsequent aman season rice. This carryover effect too, could be minimized with balanced fertilization.

  2. Salinity alters the protein composition of rice endosperm and the physicochemical properties of rice flour.

    Science.gov (United States)

    Baxter, Graeme; Zhao, Jian; Blanchard, Christopher

    2011-09-01

    Salinity is one of the major threats to production of rice and other agricultural crops worldwide. Although numerous studies have shown that salinity can severely reduce rice yield, little is known about its impact on the chemical composition, processing and sensory characteristics of rice. The objective of the current study was to investigate the effect of salinity on the pasting and textural properties of rice flour as well as on the protein content and composition of rice endosperm. Rice grown under saline conditions had significantly lower yields but substantially higher protein content. The increase in protein content was mainly attributed to increases in the amount of glutelin, with lesser contributions from albumin. Salinity also altered the relative proportions of the individual peptides within the glutelin fraction. Flours obtained from rice grown under saline conditions showed significantly higher pasting temperatures, but lower peak and breakdown viscosities. Rice gels prepared from the flour showed significantly higher hardness and adhesiveness values, compared to the freshwater controls. Salinity can significantly affect the pasting and textural characteristics of rice flour. Although some of the effects could be attributed to changes in protein content of the rice flour, especially the increased glutelin level, the impact of salinity on the physicochemical properties of rice is rather complex and may involve the interrelated effects of other rice components such as starch and lipids. Copyright © 2011 Society of Chemical Industry.

  3. Impacts of climate change on rice production in Africa and causes of simulated yield changes

    NARCIS (Netherlands)

    Oort, Van Pepijn A.J.; Zwart, Sander J.

    2018-01-01

    This study is the first of its kind to quantify possible effects of climate change on rice production in Africa. We simulated impacts on rice in irrigated systems (dry season and wet season) and rainfed systems (upland and lowland). We simulated the use of rice varieties with a higher temperature

  4. Efficacy and economics of different herbicides in aerobic rice system ...

    African Journals Online (AJOL)

    Aerobic rice system, the most promising irrigation water saving rice production technology, is highly impeded by severe weed pressure. Weed control through the use of same herbicide causes development of herbicide resistant weed biotypes and serious problem in weed management. This study was aimed at finding out ...

  5. Rice yield prediction from yield components and limiting factors

    NARCIS (Netherlands)

    Casanova, D.; Goudriaan, J.; Catala Former, M.M.; Withagen, J.C.M.

    2002-01-01

    This article aims to quantify growth at field level in relation to crop status and soil properties in irrigated direct-seeded rice. Forty fields were selected in the Ebro Delta (Spain). Rice growth was monitored and soil properties measured. Yield was related to soil properties by a deductive

  6. Rice microstructure

    Science.gov (United States)

    An understanding of plant structure is desirable to obtain a clear idea of the overall impact of a crop. A mature rice plant consists of leafy components (left in the field post-harvest) and paddy rice (collected). The rice plant is supported by a hollow stem (culm) with leaf sheaths attached to nod...

  7. Avaliação do progresso genético obtido em 22 anos no melhoramento do arroz irrigado em Minas Gerais Evaluation of the genetical progress obtained in 22 years on the improvement of irrigated rice in Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Guimarães Santos

    1999-10-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho do programa de melhoramento genético do arroz irrigado, no Estado de Minas Gerais. Foram utilizados os dados de produtividade de grãos dos ensaios comparativos avançados de cultivares e linhagens de arroz irrigado, conduzidos em várias microrregiões do Estado de Minas Gerais, durante o período de 1974/75 a 1995/96. O ganho genético médio obtido em todo o período foi de 33 kg/ha/ano (0,98%, sendo altamente significativo (PThe goal of this work was to evaluate the performance of the genetical improvement program of irrigated rice in the State of Minas Gerais, Brazil. The grain yield data of the advanced comparative trials of both cultivars and lines of irrigated rice, conducted in several regions of the State of Minas Gerais over the period of 1974/75 to 1995/1996 were utilized. The average genetical gain obtained was of 33 kg/ha/year (0.98%, being highly significant (P< 0.01. The 22 year period was subdivided into two phases: at the first phase (1974/75 to 1979/80, a gain of 203 kg/ha/year (6.06% was noticed, which was highly significant, and the second phase (1980/81 to 1995/96 presented a gain of 15 kg/ha/year (0.25% being non significant. The high gain of the first phase is ascribed to the replacement of traditional high size and poor yielding potential for breeding materials such as Inca, BG 90-2 and MG 2. In the second phase of the program, increased attention was given to obtain materials more resistant to diseases and with better grain quality and non-significant gains for yield were obtained.

  8. Irrigation and Autocracy

    DEFF Research Database (Denmark)

    Bentzen, Jeanet Sinding; Kaarsen, Nicolai; Wingender, Asger Moll

    We show that societies with a history of irrigation-based agriculture have been less likely to adopt democracy than societies with a history of rainfed agriculture. Rather than actual irrigation, the empirical analysis is based on how much irrigation potentially can increase yields.Irrigation pot...

  9. ?-Oryzanols of North American Wild Rice (Zizania palustris)

    OpenAIRE

    Aladedunye, Felix; Przybylski, Roman; Rudzinska, Magdalena; Klensporf-Pawlik, Dorota

    2013-01-01

    ?-Oryzanol, a natural mixture of ferulic acid esters of triterpene alcohols and sterols, are an important bioactive components present in rice bran oil. In light of the recent increase in the popularity of wild rice among consumers, and the possibility of a direct relationship between ?-oryzanol composition and its bioactivity, the oryzanol profile of major wild rice (Zizania palustris) grown in North America was studied and compared to regular brown rice (Oryza sativa L.). A total of twenty-...

  10. Irrigation Capability Evaluation of Illushi Floodplain, Edo State, Nigeria

    Directory of Open Access Journals (Sweden)

    A.S. Umweni

    2014-06-01

    Full Text Available Many irrigation projects, especially in the developing tropical regions, are embarked upon without any land capability assessment, resulting in avoidable and undesirable ecological consequences. The aim of this study is to assess the irrigation capability potentials of the soils of a rice growing Illushi/Ega community in Edo State of Nigeria. Soils of Illushi/Ega (200 ha were studied to establish their irrigation capabilities. Water samples were collected from the rivers within and near the sites at the proposed points of intake structures and analyzed for salinity (ECw, permeability (SAR and ion toxicity [Chlorine (Cl and Boron (B]. Gravity irrigation suitability assessment was carried out following the guidelines of the United States Bureau for Land Reclamation (USBR, 1953 and FAO (1979. Results showed that about 5.5 % of the land was non-irrigable, 11.5 % was marginally irrigable, 30.5% was moderately irrigable and 52.5 % highly irrigable.Thus about 83 % of the total land area was found to be irrigable. The results of analyses of irrigation water [ECw, SAR and Cl and B (ion toxicity problems in water sources were 0.1 – 0.7 dS m-1, 1.2 – 1.7, 0.6 – 1.8 cmol kg-1 and 0.5 – 0.7 mg kg-1] also show that there is no indication of salinity or ion toxicity problem.

  11. Assessing the impacts of climate change on rice yields in the main rice areas of China

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Fengmei [College of Earth Sciences, The Graduate University of the Chinese Academy of Sciences, 19A, Yuquan Road, Beijing, 100049 (China); Xu, Yinglong; Lin, Erda [Agricultural Environment and Sustainable Development Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 (China); Yokozawa, Masayuki [National Institute for Agro-environmental Sciences, Tsukuba 305-8604 (Japan); Zhang, Jiahua [Chinese Academy of Meteorological Sciences, Beijing, 100081 (China)

    2007-02-15

    This paper assesses the impact of climate change on irrigated rice yield using B2 climate change scenario from the Regional Climate Model (RCM) and CERES-rice model during 2071--2090. Eight typical rice stations ranging in latitude, longitude, and elevation that are located in the main rice ecological zones of China are selected for impact assessment. First, Crop Estimation through Resource and Environment Synthesis (CERES)-rice model is validated using farm experiment data in selected stations. The simulated results represent satisfactorily the trend of flowering duration and yields. The deviation of simulation within {+-} 10% of observed flowering duration and {+-} 15% of observed yield. Second, the errors of the outputs of RCM due to the difference of topography between station point and grid point is corrected. The corrected output of the RCM used for simulating rice flowering duration and yield is more reliable than the not corrected. Without CO2 direct effect on crop, the results from the assessment explore that B2 climate change scenario would have a negative impact on rice yield at most rice stations and have little impacts at Fuzhou and Kunming. To find the change of inter-annual rice yield, a preliminary assessment is made based on comparative cumulative probability at low and high yield and the coefficient variable of yield between the B2 scenario and baseline. Without the CO2 direct effect on rice yield, the result indicates that frequency for low yield would increase and it reverses for high yield, and the variance for rice yield would increase. It is concluded that high frequency at low yield and high variances of rice yield could pose a threat to rice yield at most selected stations in the main rice areas of China. With the CO2 direct effect on rice yield, rice yield increase in all selected stations.

  12. Assessing the impacts of climate change on rice yields in the main rice areas of China

    International Nuclear Information System (INIS)

    Yao, Fengmei; Xu, Yinglong; Lin, Erda; Yokozawa, Masayuki; Zhang, Jiahua

    2007-01-01

    This paper assesses the impact of climate change on irrigated rice yield using B2 climate change scenario from the Regional Climate Model (RCM) and CERES-rice model during 2071--2090. Eight typical rice stations ranging in latitude, longitude, and elevation that are located in the main rice ecological zones of China are selected for impact assessment. First, Crop Estimation through Resource and Environment Synthesis (CERES)-rice model is validated using farm experiment data in selected stations. The simulated results represent satisfactorily the trend of flowering duration and yields. The deviation of simulation within ± 10% of observed flowering duration and ± 15% of observed yield. Second, the errors of the outputs of RCM due to the difference of topography between station point and grid point is corrected. The corrected output of the RCM used for simulating rice flowering duration and yield is more reliable than the not corrected. Without CO2 direct effect on crop, the results from the assessment explore that B2 climate change scenario would have a negative impact on rice yield at most rice stations and have little impacts at Fuzhou and Kunming. To find the change of inter-annual rice yield, a preliminary assessment is made based on comparative cumulative probability at low and high yield and the coefficient variable of yield between the B2 scenario and baseline. Without the CO2 direct effect on rice yield, the result indicates that frequency for low yield would increase and it reverses for high yield, and the variance for rice yield would increase. It is concluded that high frequency at low yield and high variances of rice yield could pose a threat to rice yield at most selected stations in the main rice areas of China. With the CO2 direct effect on rice yield, rice yield increase in all selected stations

  13. Elemental composition of Malawian rice.

    OpenAIRE

    Joy, EJM; Louise Ander, E; Broadley, MR; Young, SD; Chilimba, AD; Hamilton, EM; Watts, MJ

    2016-01-01

    Widespread potential dietary deficiencies of calcium (Ca), iron (Fe), iodine (I), selenium (Se) and zinc (Zn) have been identified in Malawi. Several deficiencies are likely to be compounded by high phytic acid (PA) consumption. Rice (Oryza sativa) is commonly consumed in some Malawian populations, and its mineral micronutrient content is important for food security. The considerable irrigation requirements and flooded conditions of paddy soils can also introduce or mobilise potentially toxic...

  14. The competitiveness of domestic rice production in East Africa: A domestic resource cost approach in Uganda

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    Masao Kikuchi

    2016-03-01

    Full Text Available The rapid increase of rice imports in sub-Saharan Africa under the unstable situation in the world rice market during the 2000s has made it an important policy target for the countries in the region to increase self-sufficiency in rice in order to enhance food security. Whether domestic rice production can be competitive with imported rice is a serious question in East African countries that lie close, just across the Arabian Sea, to major rice exporting countries in South Asia. This study investigates the international competitiveness of domestic rice production in Uganda in terms of the domestic resource cost ratio. The results show that rainfed rice cultivation, which accounts for 95% of domestic rice production, does not have a comparative advantage with respect to rice imported from Pakistan, the largest supplier of imported rice to Uganda. However, the degree of non-competitiveness is not serious, and a high possibility exists for Uganda’s rainfed rice cultivation to become internationally competitive by improving yield levels by applying more modern inputs and enhancing labour productivity. Irrigated rice cultivation, though very limited in area, is competitive even under the present input-output structure when the cost of irrigation infrastructure is treated as a sunk cost. If the cost of installing irrigation infrastructure and its operation and maintenance is taken into account, the types of irrigation development that are economically feasible are not large-scale irrigation projects, but are small- and microscale projects for lowland rice cultivation and rain-water harvesting for upland rice cultivation.

  15. Assessing the groundwater recharge under various irrigation schemes in Central Taiwan

    Science.gov (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Lin, Zih-Ciao; Tsai, Cheng-Bin

    2014-05-01

    The flooded paddy fields can be considered as a major source of groundwater recharge in Central Taiwan. The risk of rice production has increased notably due to climate change in this area. To respond to agricultural water shortage caused by climate change without affecting rice yield in the future, the application of water-saving irrigation is the substantial resolution. The System of Rice Intensification (SRI) was developed as a set of insights and practices used in growing irrigated rice. Based on the water-saving irrigation practice of SRI, impacts of the new methodology on the reducing of groundwater recharge were assessed in central Taiwan. The three-dimensional finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge under different irrigation schemes. According to local climatic and environmental characteristics associated with SRI methodology, the change of infiltration rate was evaluated and compared with the traditional irrigation schemes, including continuous irrigation and rotational irrigation scheme. The simulation results showed that the average infiltration rate in the rice growing season decreased when applying the SRI methodology, and the total groundwater recharge amount of SRI with a 5-day irrigation interval reduced 12% and 9% compared with continuous irrigation (6cm constant ponding water depth) and rotational scheme (5-day irrigation interval with 6 cm initial ponding water depth), respectively. The results could be used as basis for planning long-term adaptive water resource management strategies to climate change in Central Taiwan. Keywords: SRI, Irrigation schemes, Groundwater recharge, Infiltration

  16. The Effect of Supplemental Irrigation on Canopy Temperature Depression, Chlorophyll Content, and Water Use Efficiency in Three Wheat (Triticum aestivum L. and T. durum Desf. Varieties Grown in Dry Regions of Jordan

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    Abdul Latief A. Al-Ghzawi

    2018-05-01

    Full Text Available One critical challenge facing the world is the need to satisfy the food requirements of the dramatically growing population. Drought stress is one of the main limiting factors in the wheat-producing regions; therefore, wheat yield stability is a major objective of wheat-breeding programs in Jordan, which experience fluctuating climatic conditions in the context of global climate change. In the current study, a two-year field experiment was conducted for exploring the effect of four different water regimes on the yield, yield components, and stability of three wheat (Triticum aestivum L.; T. durum Desf. Jordanian cultivars as related to Canopy Temperature Depression (CTD, and Chlorophyll Content (measured by Soil-Plant Analysis Development, SPAD. A split plot design was used in this experiment with four replicates. Water treatment was applied as the main factor: with and without supplemental irrigation; 0%, 50%, 75%, and 100% of field capacity were applied. Two durum wheat cultivars and one bread wheat cultivar were split over irrigation treatments as a sub factor. In both growing seasons, supplemental irrigation showed a significant increase in grain yield compared to the rain-fed conditions. This increase in grain yield was due to the significantly positive effect of water availability on yield components. Values of CTD, SPAD, harvest index, and water use efficiency (WUE were increased significantly with an increase in soil moisture and highly correlated with grain yield. Ammon variety produced the highest grain yield across the four water regimes used in this study. This variety was characterized by the least thermal time to maturity and the highest values of CTD and SPAD. It was concluded that Ammon had the highest stability among the cultivars tested. Furthermore, CTD and SPAD can be used as important selection parameters in breeding programs in Jordan to assist in developing high-yielding genotypes under drought and heat stress conditions.

  17. Percepção e medidas de gestão de riscos por produtores de arroz irrigado na Fronteira Oeste do Rio Grande do Sul Risk perception and risk management measures by irrigated rice growers in Fronteira Oeste, Rio Grande do Sul

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    Maria Isabel Fernandes Finger

    2013-05-01

    Full Text Available A produção agrícola apresenta características particulares, se comparada a outras atividades econômicas, sendo uma das mais marcantes a extensão dos riscos aos quais está exposta. O cultivo de arroz (Oryza sativa L. irrigado, embora pareça menos suscetível do que as culturas de sequeiro, também está exposto a riscos. Maior produtor mundial de arroz fora da Ásia, o Brasil tem no Rio Grande do Sul seu principal estado produtor. O objetivo deste trabalho foi analisar como o orizicultor da Fronteira Oeste do Rio Grande do Sul percebe os riscos da sua atividade e quais medidas adota para geri-los. A metodologia empregada envolveu aplicação presencial de questionários a orizicultores, de acordo com uma amostra não probabilística. Os resultados indicaram que os orizicultores atribuem maior relevância aos riscos socioeconômicos do que aos de produção. Evidencia-se, assim, a importância da gestão do negócio pelos orizicultores, para que sua atividade esteja integrada com os demais elos da cadeia produtiva. A redução de custos pode ser uma alternativa para mitigação de riscos de mercado, apontados como os mais relevantes pelos orizicultores. A percepção dos orizicultores sobre riscos e sobre medidas para mitigá-los pode representar a base na formulação de estratégias de gestão de riscos.Agricultural production has many different influencing factors compared to other economic activities. One of the most striking is the extent of the risks to which it is exposed. Irrigated rice (Oryza sativa L. cultivation, although seeming less susceptible than non-irrigated crops, is also exposed to risks. World's largest producer of rice outside Asia, Brazil has the state of Rio Grande do Sul as its main producer. The aim of this study was to analyze how rice farmers in Fronteira Oeste, Rio Grande do Sul realize the risks of their activity and how they manage them. Methodology involved the administration of a questionnaire, according to

  18. Effect of fluoride on photosynthesis, growth and accumulation of four widely cultivated rice (Oryza sativa L.) varieties in India.

    Science.gov (United States)

    Mondal, Naba Kumar

    2017-10-01

    Long-term use of fluoride contaminated groundwater to irrigate crops; especially paddy rice (Oryza sativa L.) has resulted in elevated soil fluoride levels in Eastern India. There is, therefore, growing concern regarding accumulation of fluoride in rice grown on these soils. A laboratory experiment was conducted to investigate the effect of F on germination and phytotoxicity of four varieties of rice (Orzya sativa L.) (MTU-1010; IET-4094; IET-4786 and GB-1) grown in petri dish in a green house with inorganic sodium fluoride (NaF). Three different levels (0, 5, 10 and 20mg/L) of NaF solution were applied. At the end of the experiment (28 days), biochemical analysis (pigment, sugar, protein, amino acid and phenol), lipid peroxidation, root ion leakage and catalase activity along with fluoride accumulation and fresh and dry weight of roots and shoots of four cultivars were measured. The results revealed that all the four studied varieties exhibited gradual decrease of germination pattern with increasing concentration of F. Pigment and growth morphological study clearly demonstrated that the variety IET-4094 was the least influenced by F compare to the other three varieties of rice. The translocation factor (TF) was recorded to be the highest for variety IET-4786 (0.215 ± 0.03) at 5mg/L F concentration. All the four varieties showed higher level of fluoride accumulation in root than in shoot. Variable results were recorded for biochemical parameters and lipid peroxidation. Catalase activity and relative conductivity (root ion leakage) gradually increased with increasing F concentration for all the four varieties. It is speculated that fluoride accumulation in rice straw at very high levels will affect the feeding cattle and such contaminated straw could be a direct threat to their health and also, indirectly, to human health via presumably contaminated meat and milk. Copyright © 2017. Published by Elsevier Inc.

  19. Agronomic and physiological impacts of irrigation frequency on green basil (Ocimum basilicum L.)

    OpenAIRE

    Gao, Peng; Dodd, Ian

    2015-01-01

    Water scarcity is a major factor restricting agricultural production and irrigation globally, with sustainable agricultural development calling for less irrigation water use and more production per unit of water applied. Improved understanding of plant physiological responses to water stress, and the effect of irrigation frequency on plant biomass production and quality, may help to optimize irrigation scheduling. Glasshouse-grown basil (Ocimum basilicum L.) received three different irrigatio...

  20. Manutenção da área foliar e produtividade de arroz irrigado com a aplicação de fertilizantes foliares no estádio de emborrachamento Foliar area maintenance and yield with application of foliar fertilizers on booting stage of irrigated rice

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    Edinalvo Rabaioli Camargo

    2008-08-01

    Full Text Available A utilização de fertilizantes foliares, aplicados ao final do ciclo da cultura do arroz irrigado, pode proporcionar complementação nutricional para a planta e proteção contra patógenos com reflexos na produtividade. O objetivo do estudo foi avaliar a utilização de fertilizantes foliares, aplicados no estádio de emborrachamento, sobre a produtividade do arroz irrigado. O experimento foi conduzido no ano agrícola 2005/2006, em área experimental de várzea do Departamento de Fitotecnia da Universidade Federal de Santa Maria. O delineamento experimental utilizado foi o de blocos ao acaso com quatro repetições. Os tratamentos foram compostos por 10 fertilizantes foliares, dois produtos aplicados via sementes, um fungicida e a testemunha. Os fertilizantes não influenciaram qualquer parâmetro avaliado. As condições climáticas e o manejo da adubação anterior à aplicação dos tratamentos foliares propiciaram condições favoráveis para o arroz expressar o seu potencial produtivo, em torno de 10.000kg ha-1. Neste nível de produtividade, os produtos utilizados não aumentaram a produtividade do arroz irrigado.The use of foliar fertilizers applied to the reproductive phase of rice can improve the plant nutrition and protect the field against foliar diseases with gains in yield. The objective of this experiment was to evaluate the use of the foliar fertilizers applied to the booting stage in order to verify the irrigated rice yield. The experiment was carried out in 2005/06 in a lowland area in Santa Maria-RS, Brazil. The treatments, arranged in a randomized block design with four replications, were constituted by 10 foliar fertilizers available in the market, two products applied to seeds, a fungicide, and a check treatment. The treatments presented no effects on any of the variables studied. The suitable climatic conditions and the fertilizer management carried out before the application of the foliar treatments led to the

  1. IMPACTS OF CLIMATE CHANGE ON RICE AGRICULTURE IN NIGERIA

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    Joshua Olusegun Ajetomobi

    2011-01-01

    This study employed the Ricardian approach to test the relative importance of climate normals (average long-term temperature and precipitation in explaining net revenue from Nigerian rice agriculture under irrigation and dry land conditions.   A survey was done by interviewing 1200 rice farmers from 20 rice producing states in Nigeria. The states covered all the six geopolitical zones in the country. The results showed that increase in temperature will reduce net revenue for dry land rice farms while net revenue rises with increase in temperature for irrigated rice farms. Precipitation had similar effects on rice net revenue. Increase in precipitation will cause reduction in revenue for dry land rice farms whereas it will cause increase in revenue for irrigated farms. The results clearly demonstrate irrigation as a significant techniques used by the farmers to adapt to the climate change. Other adaptation options include Keeping of livestock, engaging in off farm works and the use of different market channels.  Â

  2. Nutrição mineral de mudas de eucalipto produzidas sob diferentes lâminas de irrigação e substratos Mineral nutrition of eucalypt seedlings grown under different irrigation levels and substrates

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    Jane Luísa Wadas Lopes

    2007-08-01

    Full Text Available Este trabalho teve como objetivo avaliar os efeitos das lâminas brutas de irrigação na concentração de nutrientes de mudas de Eucalyptus grandis, produzidas em diferentes substratos. O experimento foi realizado na Camará - Mudas Florestais, em Ibaté, SP, e constituiu-se de um fatorial 5 x 4, sendo cinco lâminas brutas de irrigação diárias (6, 8, 10, 12 e 14 mm, aplicadas em diferentes horários (10, 13 e 16 h, e quatro substratos (FB - fibra de coco; CPV - casca de pinus e vermiculita; CATV - casca de pinus, carvão, turfa e vermiculita; e um MIX - 70 % de CPV e 30 % de FB. Foram determinadas os conteúdos dos nutrientes na parte aérea e no sistema radicular das mudas. Os resultados indicaram que houve influência das lâminas de irrigação e dos substratos no conteúdo dos nutrientes das mudas com maior acúmulo dos mesmos à medida que o fornecimento de água foi maior. As plantas crescidas nos substratos FB e CPV registraram os maiores acúmulos de nutrientes. CPV foi o melhor em se tratando do acúmulo dos macronutrientes nas raízes e também, juntamente com FB, o melhor para o acúmulo dos micronutrientes nas raízes e na parte aérea. Não houve influência dos substratos no acúmulo dos macronutrientes na parte aérea, porém houve das lâminas de irrigação.The objective of this work was to evaluate the effects of gross irrigation depths on the nutrient concentration of Eucalyptus grandis seedlings, produced in different substrates. The experiment was carried out in Camará - Mudas Florestais, in Ibaté, São Paulo, in a factorial 5 x 4, with five daily irrigation levels (6, 8, 10, 12 and 14 mm, applied three times a day (at 10 am, 13 pm and 16 pm, on four substrates (FB- coconut fiber; CPV- pine bark and vermiculite; CATV- pine bark, coal, turf and vermiculite and MIX- 70 % CPV and 30 % FB. The nutrient concentration was determined in the aerial part and roots of the seedlings, which was influenced by irrigation levels

  3. Assessing the changes of groundwater recharge / irrigation water use between SRI and traditional irrigation schemes in Central Taiwan

    Science.gov (United States)

    Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

    2015-04-01

    To respond to agricultural water shortage impacted by climate change without affecting rice yield in the future, the application of water-saving irrigation, such as SRI methodology, is considered to be adopted in rice-cultivation in Taiwan. However, the flooded paddy fields could be considered as an important source of groundwater recharge in Central Taiwan. The water-saving benefit of this new methodology and its impact on the reducing of groundwater recharge should be integrally assessed in this area. The objective of this study was to evaluate the changes of groundwater recharge/ irrigation water use between the SRI and traditional irrigation schemes (continuous irrigation, rotational irrigation). An experimental paddy field located in the proximal area of the Choushui River alluvial fan (the largest groundwater pumping region in Taiwan) was chosen as the study area. The 3-D finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge process and amount under traditional irrigation schemes and SRI methodology. The use of effective rainfall was taken into account or not in different simulation scenarios for each irrigation scheme. The simulation results showed that there were no significant variations of infiltration rate in the use of effective rainfall or not, but the low soil moisture setting in deep soil layers resulted in higher infiltration rate. Taking the use of effective rainfall into account, the average infiltration rate for continuous irrigation, rotational irrigation, and SRI methodology in the first crop season of 2013 were 4.04 mm/day, 4.00 mm/day and 3.92 mm/day, respectively. The groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reducing 4% and 2% compared with continuous irrigation and rotational irrigation, respectively. The field irrigation requirement amount of SRI methodology was significantly

  4. Tropical Legume Crop Rotation and Nitrogen Fertilizer Effects on Agronomic and Nitrogen Efficiency of Rice

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    Motior M. Rahman

    2014-01-01

    Full Text Available Bush bean, long bean, mung bean, and winged bean plants were grown with N fertilizer at rates of 0, 2, 4, and 6 g N m−2 preceding rice planting. Concurrently, rice was grown with N fertilizer at rates of 0, 4, 8, and 12 g N m−2. No chemical fertilizer was used in the 2nd year of crop to estimate the nitrogen agronomic efficiency (NAE, nitrogen recovery efficiency (NRE, N uptake, and rice yield when legume crops were grown in rotation with rice. Rice after winged bean grown with N at the rate of 4 g N m−2 achieved significantly higher NRE, NAE, and N uptake in both years. Rice after winged bean grown without N fertilizer produced 13–23% higher grain yield than rice after fallow rotation with 8 g N m−2. The results revealed that rice after winged bean without fertilizer and rice after long bean with N fertilizer at the rate of 4 g N m−2 can produce rice yield equivalent to that of rice after fallow with N fertilizer at rates of 8 g N m−2. The NAE, NRE, and harvest index values for rice after winged bean or other legume crop rotation indicated a positive response for rice production without deteriorating soil fertility.

  5. Avaliação da porosidade e placa férrica de raízes de arroz cultivado em hipoxia Evaluation of porosity and iron plaque on rice roots grown under hypoxia

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    Marquel Jonas Holzschuh

    2010-10-01

    servir como estimativa da formação de aerênquima no arroz. O método de obtenção de raízes foi eficiente em promover a eliminação de O2 do saco de vinil para estudar a formação do aerênquima.The high oxygen diffusion in different materials makes the establishment and maintenance of oxygen-free environments difficult. The techniques used to obtain oxygen-free environments are little efficient and not representative of flooded soil conditions. The purpose of this study was to develop a method for obtaining roots in a hypoxic environment to evaluate iron plaque and aerenchyma formation in rice plants. A hypoxic condition similar to that of flooded soils was created in 50 L tanks, based on the oxygen diffusion capacity through vinyl plastic in contact with flooded soil. Each tank was filled with soil (Gley soil, five vinyl bags and then flooded. Rice plants of the genotypes IRGA 423 and IRGA 424 grown in the field were collected, the roots cut at the stem, washed and 1/3 of the leaves removed. Each bag was filled with 12 plants of each genotype and nutrient solution. After seven days, the new adventitious roots were used to determine the iron plaque and aerenchyma formation in the segments 0-2, 2-4 and 4-6 cm from the root tips. The roots were exposed the solution of a flooded soil for 4 hours. The iron plaque was determined in the root segments after iron extraction with HCl 0.5 mol L-1. Porosity was determined in vacuum cycles applied with a syringe. The weight difference before and after vacuum treatment and water entrance was assumed as estimate of the magnitude of the aerenchyma of the roots. The method was tested with the production of new adventitious roots in vinyl bags under aerated and hypoxic conditions. Root porosity was higher in the hypoxic than in the aerated environment. Porosity was higher near plant base and as porosity increased, iron increased near the root surface, indicating the iron plaque as a parameter to estimate aerenchyma formation in

  6. Manejo da irrigação na cultura do crisântemo em vaso, cultivar rage, cultivado em ambiente protegido Irrigation schedule in pot chrysanthemum, cultivar rage, grown in greenhouse

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    Maryzélia F. de Farias

    2004-04-01

    Full Text Available Dentre as dificuldades que os produtores têm encontrado ao adotarem o cultivo em ambiente protegido, destaca-se a falta de dados específicos sobre o uso racional da água e o desconhecimento da quantidade e do momento de irrigar. Esta pesquisa foi desenvolvida na propriedade de um produtor, no Distrito de Holambra II, região de Paranapanema - SP, em cultivos rotineiramente desenvolvidos pelo produtor, buscando melhor representatividade dos dados obtidos. O objetivo principal deste experimento foi identificar a tensão de água no solo que pudesse resultar em melhor qualidade comercial da cultivar de crisântemo "Rage", cultivado em vaso e mantido em ambiente protegido. O delineamento experimental foi o inteiramente casualizado, com duas repetições. Os tratamentos foram definidos por seis níveis de tensão de água: -2; -3; -4; -6; -10 e -30 kPa. Para cada tensão, foram calculadas a altura correspondente na coluna de mercúrio do tensiômetro, as lâminas e o tempo de irrigação. Os resultados obtidos demonstraram que a cultivar Rage obteve a maior porcentagem de vasos de alta qualidade (A1 no tratamento irrigado com a tensão de -4 kPa. O tratamento irrigado, quando atingia -30 kPa, resultou na menor porcentagem de vasos A1.The most important difficulty that the producers have been found to adopt the cultivation in plastic greenhouses is the lack of specific data on the rational use of the water and informations about when and how much water apply. This research was developed in a farm in Paranapanema - SP, Brazil, with tradition in pot chrysanthemum grow. The main objective was to identify the soil water tension that could result in better commercial quality of chrysanthemum Rage, cultivated in pot and maintained in greenhouse. The treatments were defined for six levels of substrate water tension: -2; -3; -4; -6; -10 and -30 kPa. The irrigation time was defined for each tension and also the equivalent height int the mercury column of

  7. Mapping rice-fallow cropland areas for short-season grain legumes intensification in South Asia using MODIS 250 m time-series data

    Science.gov (United States)

    Gumma, Murali Krishna; Thenkabail, Prasad S.; Teluguntla, Pardhasaradhi G.; Rao, Mahesh N.; Mohammed, Irshad A.; Whitbread, Anthony M.

    2016-01-01

    The goal of this study was to map rainfed and irrigated rice-fallow cropland areas across South Asia, using MODIS 250 m time-series data and identify where the farming system may be intensified by the inclusion of a short-season crop during the fallow period. Rice-fallow cropland areas are those areas where rice is grown during the kharif growing season (June–October), followed by a fallow during the rabi season (November–February). These cropland areas are not suitable for growing rabi-season rice due to their high water needs, but are suitable for a short -season (≤3 months), low water-consuming grain legumes such as chickpea (Cicer arietinum L.), black gram, green gram, and lentils. Intensification (double-cropping) in this manner can improve smallholder farmer’s incomes and soil health via rich nitrogen-fixation legume crops as well as address food security challenges of ballooning populations without having to expand croplands. Several grain legumes, primarily chickpea, are increasingly grown across Asia as a source of income for smallholder farmers and at the same time providing rich and cheap source of protein that can improve the nutritional quality of diets in the region. The suitability of rainfed and irrigated rice-fallow croplands for grain legume cultivation across South Asia were defined by these identifiers: (a) rice crop is grown during the primary (kharif) crop growing season or during the north-west monsoon season (June–October); (b) same croplands are left fallow during the second (rabi) season or during the south-east monsoon season (November–February); and (c) ability to support low water-consuming, short-growing season (≤3 months) grain legumes (chickpea, black gram, green gram, and lentils) during rabi season. Existing irrigated or rainfed crops such as rice or wheat that were grown during kharif were not considered suitable for growing during the rabi season, because the moisture/water demand of these crops is too high. The

  8. Making Rice Production More Environmentally-Friendly

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    Norman Uphoff

    2016-05-01

    Full Text Available Irrigated rice production is one of the most essential agricultural activities for sustaining our global population, and at the same time, one of the agricultural sectors considered most eco-unfriendly. This is because it consumes a larger share of available freshwater resources, competing with varied ecosystems as well as other economic sectors; its paddy fields are responsible for significant emission of greenhouse gases; and the reliance on chemical fertilizers and various agrochemicals contributes to pollution of soils and water systems. These stresses on soils, hydrology and atmosphere are actually not necessary for rice production, which can be increased by modifying agronomic practices though more agroecologically-sound management practices. These, combined under the rubric of the System of Rice Intensification (SRI, can reduce requirements of irrigation water, chemical fertilizer and agrochemicals while increasing paddy yields and farmer’s net incomes. Here we discuss how irrigated rice production can be made more eco-friendly for the benefit of farmers, consumers and the environment. This is achieved by introducing practices that improve the growth and functioning of rice plants’ root systems and enhance the abundance, diversity and activity of beneficial soil organisms that live around plant roots and within the plants themselves as symbiotic endophytes.

  9. Change in Localizations of Arsenic in Rice Grains After Cooking with High Arsenic Waters - µXRF and XANES studies

    Science.gov (United States)

    Datta, S.; Ryan, B.; Kumar, N.; Bortz, T.; Bolen, Z. T.

    2016-12-01

    Threats of Arsenic (As) through food uptake, via consumption of rice, is a potential pathway that presents a concern not only for the millions of inhabitants who reside in river valleys and irrigate their soil with contaminated water, but the global rice market as well. This study focuses on high As rice from India and Bangladesh grown in such soils, and the effect of boiling rice with As-contaminated water in preparation for dietary intake. Husked and unhusked rice grains were boiled with >500 µg/L As-bearing water from the field to simulate local cooking methods. The resulting cooked water was analyzed using iCAP low limit detection via ICP-MS to understand the changes in dissolved elemental concentrations before and after cooking, and HPLC was introduced to measure for changes in As speciation in the waters. Using spectroscopic methods such as µXRF mapping associated with µXANES, distribution/localization and speciation changes of As in rice grains were identified. Further, with Linear Combination Fitting (LCF) of XANES spectra utilizing relevant reference compounds (As-S, AsIII, AsV, MMA and DMA), organic and inorganic As species were able to be mapped within rice grains. The results for uncooked/raw grains showed that predominantly As-S combined with AsIII and AsV accounted for 90% of speciation in most samples, localized in areas such as the outer aleurone layer. When analyzing cooked rice grains, the speciation appears to be an unidentified As species while the best LCF shows between 63-93% of As as MMA. Arsenic was found less localized throughout the cooked grains but rather heterogeneously distributed when compared to the uncooked/raw samples. The analyses of boiled/cooked water resulted in a significant decrease in dissolved As post-cooking (90%), but a subsequent increase in elements such as K, La, Li, Mo, Na, Ni, and Zr was observed; As-V was shown to be the main in-As species in the cooked water. The impact that this study portrays is consuming rice

  10. Impacts of Irrigation Practices on Groundwater Recharge in Mississippi Delta Using coupled SWAT-MODFLOW Model

    Science.gov (United States)

    Gao, F.; Feng, G.; Han, M.; Jenkins, J.; Ouyang, Y.

    2017-12-01

    The Lower Mississippi River alluvial plain (refers to as MS Delta), located in the northwest state of Mississippi, is one of the most productive agricultural region in the U.S. The primary crops grown in this region are soybean, corn, cotton, and rice. Approximately 80% water from the alluvial aquifer in MS Delta are withdrawn for irrigation, which makes it the most used aquifer in the State. As a result, groundwater level has declined > 6 m since 1970, which threaten the sustainability of irrigated agriculture in this region. The objectives of this study were to: 1) couple the SWAT and MODFLOW then calibrate and validate the incorporated model outputs for stream flow, groundwater level and evapotranspiration (ET) in MS Delta; 2) simulate the groundwater recharge as affected by a) conventional irrigation scheme, b) no irrigation scheme, c) ET based and soil moisture based full irrigation schedules using all groundwater, and d) ET and soil moisture based full irrigation schedule using different percentages of surface and ground water. Results indicated that the coupled model performed well during the calibration and validation for daily stream flow at three USGS gauge stations. (R2=0.7; Nash-Sutcliffe efficiency (NSE) varied from 0.6 to 0.7; Root Mean Square Error (RMSE) ranged from 20 to 27 m3/s). The values of determination coefficient R2 for groundwater level were 0.95 for calibration and 0.88 for validation, their NSE values were 0.99 and 0.93, respectively. The values of RMSE for groundwater level during the calibration and validation period were 0.51 and 0.59 m. The values of R2, NSE and RMSE between SWAT-MODFLOW simulated actual evapotranspiration (ET) and remote sensing evapotranspiration (ET) were 0.52, 0.51 and 28.1 mm. The simulated total average monthly groundwater recharge had lower values of 19 mm/month in the crop season than 30 mm/month in the crop off-growing season. The SWAT-MODFLOW can be a useful tool for not only simulating the recharge in MS

  11. Impact of Water Management on Rice Varieties, Yield, and Water Productivity under the System of Rice Intensification in Southern Taiwan

    Directory of Open Access Journals (Sweden)

    Victoriano Joseph Pascual

    2016-12-01

    Full Text Available The system of rice intensification (SRI uses less water and enhances rice yield through synergy among several agronomic management practices. This claim was investigated to determine the effects of crop growth, yield and irrigation water use, using two thirds of the recommended SRI practices and two rice varieties, namely Tainan11 (TN11 and Tidung30 (TD30. Irrigation regimes were (a intermittent irrigation with three-day intervals (TD303 and TN113; (b intermittent irrigation with seven-day intervals (TD307 and TN117 and (c continuous flooding (TD30F and TN11F. Results showed that intermittent irrigation of three- and seven-day intervals produced water savings of 55% and 74% compared with continuous flooding. Total water productivity was greater with intermittent irrigation at seven-day intervals producing 0.35 kg·grain/m3 (TN117 and 0.46 kg·grain/m3 (TD307. Average daily headed panicle reduced by 166% and 196% for TN113 and TN117 compared with TN11F, with similar reduction recorded for TD303 (150% and TD307 (156% compared with TD30F. Grain yield of TD30 was comparable among irrigation regimes; however, it reduced by 30.29% in TN117 compared to TN11F. Plant height and leaf area were greater in plants exposed to intermittent irrigation of three-day intervals.

  12. The absorption and distribution of Cesium-134 in rice-soil system

    International Nuclear Information System (INIS)

    Xu Yinliang; Chen Chuanqun; Chen Bin; Sun Zhiming

    1991-01-01

    Dynamics of absorption of 134 Cs by rice shows that absorption rate is the fastest at boot stage; absorption capacities of 134 Cs in soils are different with the different physical-chemical properties of soils; absorption amounts vary with the time of irrigating 134 Cs; the closer the irrigation time to mature stage is, the more the absorption amount of 134 Cs in rice will be; the more the irrigating times are, and the higher the radioactivity of 134 Cs in irrigating water is, the more the absorption amount in rice will be. After brown rice is polished, contamination of 134 Cs can be decreased by 22.6-45.6%. The order of specific activity in rice is: bran > root > straw > husk > polished rice. Percentage activity of straw, brown rice, root and husk is 51.4%, 28.4%, 11.8% and 8.4% respectively. The migration of 134 Cs is very slow in soil and 95.1% of 134 Cs is concentrated in surface soil (0-2.5 cm). The distribution ratio of 134 Cs in the rice and soil is 6.1%:93.9%. Potassium ion can inhibit the absorption of 134 Cs by rice. There is an exponential function between the concentration of potassium ion and specific activity of 134 Cs in rice

  13. Ghana - Agriculture - Irrigation

    Data.gov (United States)

    Millennium Challenge Corporation — The Millennium Development Authority (MiDA) financed the construction of a new irrigation scheme in Kpong and the renovation of two irrigation schemes in Botanga and...

  14. Irrigation et paludisme : un couple infernal?

    Directory of Open Access Journals (Sweden)

    Mergeai, G.

    2016-01-01

    Full Text Available Irrigation and Malaria - a Terrible Combination?. Increasing agricultural productivity is a priority in most of the developing countries and using irrigation is one of the most efficient ways of achieving this goal. Almost half a billion people in the world contract malaria every year and approximately one million die as a result. The majority of these victims are farmers or members of their families. In infected areas, malaria continues to have major negative impacts on agricultural productivity. For example, in the Equateur province of the DRC, after access to production means, fevers are considered the second biggest obstacle to the development of agricultural activities. In the Ivory Coast, a study has shown that growers suffering from malaria were about half as productive as their healthy colleagues. The disease often strikes at the start of the rainy season when work begins again in the fields. It reduces the amount of land cultivated and affects the amount of care taken with crops. Agricultural practices influence the risk of contracting malaria. Irrigation, in particular, can encourage the proliferation of vectors of the disease and make it more likely to spread. This tendency can be observed in many locations where irrigated rice production is on the increase. Paradoxically, however, an increased number of mosquitoes does not systematically result in more malaria. In Ethiopia, malaria is more prevalent close to the micro-dams sponsored by the government, whereas, in Tanzania, there is less malaria in irrigated areas. Various theories can be put forward in order to explain this paradox. In particular, increased income due to higher rice yields enables farmers to purchase insecticide-treated mosquito nets. It also allows them to eat better, which strengthens their immune systems. It also appears that the negative impact of irrigation systems is greater in areas, in which immunity levels were low in the population prior to the creation of

  15. Online decision support system for surface irrigation management

    Science.gov (United States)

    Wang, Wenchao; Cui, Yuanlai

    2017-04-01

    Zhanghe Irrigation District (Center China) to manage the required irrigation deliveries. Two years' application indicates that the proposed OIDSS can achieve promising performance for surface irrigation. Historical data of rice growing period in 2014 has been applied to test the OIDSS: it gives out 3 irrigation decisions, which is consistent with actual irrigation times and the forecast irrigation dates are well fit with the actual situations; the corresponding amount of total irrigation decreases by 15.13% compared to those without using the OIDSS.

  16. Crop response of aerobic rice and winter wheat to nitrogen, phosphorus and potassium in a double cropping system

    NARCIS (Netherlands)

    Dai, X.Q.; Zhang, H.Y.; Spiertz, J.H.J.; Yu, J.; Xie, G.H.; Bouman, B.A.M.

    2010-01-01

    In the aerobic rice system, adapted rice cultivars are grown in non-flooded moist soil. Aerobic rice may be suitable for double cropping with winter wheat in the Huai River Basin, northern China plain. Field experiments in 2005 and 2006 were conducted to study the response of aerobic rice and winter

  17. Root canal irrigants

    OpenAIRE

    Kandaswamy, Deivanayagam; Venkateshbabu, Nagendrababu

    2010-01-01

    Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are...

  18. IRRIGATION USING SOLAR PUMP

    OpenAIRE

    Prof. Nitin P.Choudhary*1 & Ms. Komal Singne2

    2017-01-01

    In this report the described design of a PV and soil moisture sensor based automated irrigation system is introduced. This project aims to provide a human friendly, economical and automated water pumping system which eliminates the problems of over irrigation and helps in irrigation water optimization and manage it in accordance with the availability of water. Our project not only tries to modernize the irrigation practices and ensure the optimum yield by carefully fulfilling the requirements...

  19. Root Zone Sensors for Irrigation Management in Intensive Agriculture

    Directory of Open Access Journals (Sweden)

    Jochen Hemming

    2009-04-01

    Full Text Available Crop irrigation uses more than 70% of the world’s water, and thus, improving irrigation efficiency is decisive to sustain the food demand from a fast-growing world population. This objective may be accomplished by cultivating more water-efficient crop species and/or through the application of efficient irrigation systems, which includes the implementation of a suitable method for precise scheduling. At the farm level, irrigation is generally scheduled based on the grower’s experience or on the determination of soil water balance (weather-based method. An alternative approach entails the measurement of soil water status. Expensive and sophisticated root zone sensors (RZS, such as neutron probes, are available for the use of soil and plant scientists, while cheap and practical devices are needed for irrigation management in commercial crops. The paper illustrates the main features of RZS’ (for both soil moisture and salinity marketed for the irrigation industry and discusses how such sensors may be integrated in a wireless network for computer-controlled irrigation and used for innovative irrigation strategies, such as deficit or dual-water irrigation. The paper also consider the main results of recent or current research works conducted by the authors in Tuscany (Italy on the irrigation management of container-grown ornamental plants, which is an important agricultural sector in Italy.

  20. Irrigation in endodontic treatment.

    Science.gov (United States)

    Basrani, Bettina

    2011-01-01

    The primary endodontic treatment goal is to optimize root canal disinfection and to prevent reinfection. Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal system. In this review of the literature, various irrigants and the interactions between irrigants are discussed and new delivery systems are introduced.

  1. The dynamics of rice production in Indonesia 1961–2009

    Directory of Open Access Journals (Sweden)

    Dyah R. Panuju

    2013-01-01

    Full Text Available Rice is one of the important agricultural products in Indonesia. The production has been fully supported by infrastructure including research and development as well as government regulations in pricing. Its vulnerability to climate change requires adaptation strategies on irrigation, biotechnology and selection of alternative crops. The primary goal of this paper was to evaluate the historical perspective of the dynamics of rice production, technologies particularly in seed inventions, labour in farming and consumption of rice from 1961 to 2009 in conjunction with land capability. The study of historical rice production could be a benefit for future agricultural planning in Indonesia.

  2. Exploring traditional aus-type rice for metabolites conferring drought tolerance.

    Science.gov (United States)

    Casartelli, Alberto; Riewe, David; Hubberten, Hans Michael; Altmann, Thomas; Hoefgen, Rainer; Heuer, Sigrid

    2018-01-25

    Traditional varieties and landraces belonging to the aus-type group of rice (Oryza sativa L.) are known to be highly tolerant to environmental stresses, such as drought and heat, and are therefore recognized as a valuable genetic resource for crop improvement. Using two aus-type (Dular, N22) and two drought intolerant irrigated varieties (IR64, IR74) an untargeted metabolomics analysis was conducted to identify drought-responsive metabolites associated with tolerance. The superior drought tolerance of Dular and N22 compared with the irrigated varieties was confirmed by phenotyping plants grown to maturity after imposing severe drought stress in a dry-down treatment. Dular and N22 did not show a significant reduction in grain yield compared to well-watered control plants, whereas the intolerant varieties showed a significant reduction in both, total spikelet number and grain yield. The metabolomics analysis was conducted with shoot and root samples of plants at the tillering stage at the end of the dry-down treatment. The data revealed an overall higher accumulation of N-rich metabolites (amino acids and nucleotide-related metabolites allantoin and uridine) in shoots of the tolerant varieties. In roots, the aus-type varieties were characterised by a higher reduction of metabolites representative of glycolysis and the TCA cycle, such as malate, glyceric acid and glyceric acid-3-phosphate. On the other hand, the oligosaccharide raffinose showed a higher fold increase in both, shoots and roots of the sensitive genotypes. The data further showed that, for certain drought-responsive metabolites, differences between the contrasting rice varieties were already evident under well-watered control conditions. The drought tolerance-related metabolites identified in the aus-type varieties provide a valuable set of protective compounds and an entry point for assessing genetic diversity in the underlying pathways for developing drought tolerant rice and other crops.

  3. Managing flood prone ecosystem for rice production in Bihar plains

    International Nuclear Information System (INIS)

    Khan, A.R.; Singh, S.S.

    2002-06-01

    A large area of the eastern region especially Bihar (0.5 million hectare) faces flood submergence and/or drought every year which creates an unfavorable environment for crop production. In this ecosystem only flood prone rice is grown whose cultivation is entirely different than normal rice crop. Managing the flood prone ecosystem for rice production needs to evaluate the reasons and a comprehensive appropriate technology through research efforts for better rice production under such harsh ecology. An attempt was made to develop a suitable agronomic package for rice cultivation during and after flooding in flood prone plains of Bihar. (author)

  4. Avaliação de linhagens de arroz irrigado com tipo de grão para a culinária japonesa para o Estado de Roraima. = Evaluation of irrigated rice strains with grain type for Japanese cuisine in the State of Roraima.

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Centeno Cordeiro

    2010-12-01

    and quality of irrigated rice strains with grain types for Japanese cuisine, under the cropping conditions of Roraima. From December 2003 to March 2004, ten strains of irrigated rice were evaluated in a randomized block experimentaldesign, with four replications. In addition to the agronomic traits it was also evaluated the quality of the grains. The strain CNAi9903 was the most suitable relative to the characteristic of low amylose content, presenting good productivity and adaptation tothe growing conditions in lowland of Roraima, and therefore the greatest potential for use in Japanese cuisine.

  5. affect rice in integrated rice-fish culture in Lake Victoria Basin, Kenya?

    African Journals Online (AJOL)

    AGHOGHO A

    Rice field ecology and fish culture - an overview. Hydrobiologia 259:91-113. Fernando CH, Halwart M (2000). Fish farming in irrigation systems. Fisheries Management and Ecol. 7:45-54. Frei M, Razzak MA, Hossain MM, Ochme M, Dewan S, Becker K. (2007). Performance of common carp, Cyprinus carpio L. and Nile.

  6. Effect of salt stress on germination and early seedling growth of rice ...

    African Journals Online (AJOL)

    USER

    2010-03-29

    Mar 29, 2010 ... planting in saline soil or in areas inundated by sea water or irrigated with brackish ... Nutritional imbalance caused by such ions leads to reduction in ... rice varieties showed a great variation in germination due to salinity effect.

  7. Elemental composition of Malawian rice.

    Science.gov (United States)

    Joy, Edward J M; Louise Ander, E; Broadley, Martin R; Young, Scott D; Chilimba, Allan D C; Hamilton, Elliott M; Watts, Michael J

    2017-08-01

    Widespread potential dietary deficiencies of calcium (Ca), iron (Fe), iodine (I), selenium (Se) and zinc (Zn) have been identified in Malawi. Several deficiencies are likely to be compounded by high phytic acid (PA) consumption. Rice (Oryza sativa) is commonly consumed in some Malawian populations, and its mineral micronutrient content is important for food security. The considerable irrigation requirements and flooded conditions of paddy soils can also introduce or mobilise potentially toxic elements including arsenic (As), cadmium (Cd) and lead (Pb). The aim of this study was to determine the mineral composition of rice sampled from farmers' fields and markets in Malawi. Rice was sampled from 18 extension planning areas across Malawi with 21 white (i.e. polished) and 33 brown samples collected. Elemental composition was determined by inductively coupled plasma-mass spectrometry (ICP-MS). Arsenic speciation was performed using high-performance liquid chromatography (HPLC)-ICP-MS. Concentration of PA was determined using a PA-total phosphorus assay. Median total concentrations (mg kg -1 , dry weight) of elements important for human nutrition in brown and white rice, respectively, were: Ca = 66.5 and 37.8; Cu = 3.65 and 2.49; Fe = 22.1 and 7.2; I = 0.006 and rice samples, respectively, median PA concentrations were 5438 and 1906 mg kg -1 , and median PA:Zn molar ratios were 29 and 13. Concentrations of potentially toxic elements (mg kg -1 , dry weight) in brown and white rice samples, respectively, were: As = 0.030 and 0.006; Cd  ≤ 0.002 and 0.006; Pb = 0.008 and 0.008. Approximately 95 % of As was found to be inorganic As, where this could be quantified. Malawian rice, like the more widely consumed staple grain maize, contains inadequate Ca, I, Se or Zn to meet dietary requirements. Biofortification strategies could significantly increase Se and Zn concentrations and require further investigation. Concentrations of Fe in rice grain varied

  8. Evaluation of the ORYZA2000 Rice Growth Model under Nitrogen-Limited Conditions in an Irrigated Mediterranean Environment Evaluación del Modelo de Crecimiento de Arroz ORYZA2000 bajo Condiciones Limitadas de Nitrógeno en un Ambiente Mediterráneo Regado

    Directory of Open Access Journals (Sweden)

    Pamela Artacho

    2011-03-01

    Full Text Available ORYZA2000 is a growth model for tropical lowland rice ( Oryza sativa L. developed by the International Rice Research Institute and Wageningen University. This model has been evaluated extensively in a wide range of environments. However, reports examining japonica cultivars growing in temperate climates are scarce. In this study, ORYZA2000 was calibrated and evaluated using data from experiments carried out in the South-Central area of Chile. These experiments were performed on a japonica rice cultivar growing under an irrigated Mediterranean environment at various N rates. ORYZA2000 was then applied to explore potential yield and grain yield response to N fertilization under likely weather conditions in the major rice-producing area in Chile. ORYZA2000 was sufficiently accurate to simulate grain yield and crop N uptake at the end of the season. Final crop N uptake was simulated with a root mean squared error (RMSE of 20 kg ha-1 (15% and grain yield with a RMSE of 1666 kg ha-1 (19%. However, the prediction of biomass and N uptake of individual organs throughout the season was poor. A long-term simulation study confirmed a potential yield as high as 12 000 kg ha-1 in the Parral area, as well as the existence of a scope for yield increase. The yield response to N fertilization was predicted even at rates of 300 kg ha-1, although a significant probability of low yields was also observed. This trend supports the need to incorporate dynamic N management in Chilean rice production.ORYZA2000 es un modelo para arroz tropical regado desarrollado por el Instituto Internacional de Investigación en Arroz y Universidad de Wageningen, que ha sido evaluado en un amplio rango de ambientes. Sin embargo, los reportes para cultivares japónica creciendo en ambientes templados son escasos. En este estudio, ORYZA2000 fue calibrado y evaluado usando datos de experimentos realizados en el centro-sur de Chile, que incluyeron una variedad japónica cultivada bajo un

  9. Preliminary studies in rice-fish culture in a rainfed lowland ecology ...

    African Journals Online (AJOL)

    Preliminary studies in rice-fish culture in a rainfed lowland ecology in Ghana. PKA Dartey, RK Bam, J Ofori. Abstract. Mixed farms of rice and fish are yet to receive attention in Ghana, despite lowland rice being grown under inundation in most areas nationwide. In a preliminary study, Nile tilapia (Oreochromis niloticus) was ...

  10. Preliminary studies in rice-fish culture in a rainfed lowland ecology ...

    African Journals Online (AJOL)

    Mixed farms of rice and fish are yet to receive attention in Ghana, despite lowland rice being grown under inundation in most areas nationwide. In a preliminary study, Nile tilapia (Oreochromis niloticus) was successfully cultured in a rainfed lowland rice farm, although no additional care was provided for fishes. The highest ...

  11. Labelling of rice seedlings and rice plants with 32P

    International Nuclear Information System (INIS)

    Achmad Nasroh, K.

    1989-01-01

    Labelling of rice seedlings and rice plants with 32 P. Labelled rice seedlings can be used to tag insect pests that feed on. Radioactivity counting of 32 P in the endosperm and in the shoot of rice seeds that soaked for 72 hours in KH 2 32 PO 4 solution of 1 μCi/ml were 29,300 and 9,500 cpm respectively. When these labelled seedlings were grown in unlabelled medium the radioactivity in the shoot increased. It was due to the 32 P that was translocated to the shoot from the endosperm. The 32 P translocation reached maximum about one week after the seedling were grown in the unlabelled medium. Labelled seedlings could also be produced by growing 5, 10 and 15 days old seedlings hydroponically in Kimura B solution containing 32 P. Ten days after growing, the radioactivity concentration of the seedlings stem reached about 115,000; 85,000 and 170,000 cpm/mg dry weight for the 5, 10 and 15 days old seedlings respectively. For the implementation of this method, 20 ml labelled Kimura B was needed for labelling of one seedling. The seedlings should be prepared in tap water. During the growth the 32 P in the labelled seedlings was distributed throughout the plant, so that new leaves and tillers became also radioactive. (author). 5 refs

  12. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice

    Science.gov (United States)

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E.; Qiang, Sheng

    2015-01-01

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China. PMID:26012494

  13. Cytoplasmic-genetic male sterility gene provides direct evidence for some hybrid rice recently evolving into weedy rice.

    Science.gov (United States)

    Zhang, Jingxu; Lu, Zuomei; Dai, Weimin; Song, Xiaoling; Peng, Yufa; Valverde, Bernal E; Qiang, Sheng

    2015-05-27

    Weedy rice infests paddy fields worldwide at an alarmingly increasing rate. There is substantial evidence indicating that many weedy rice forms originated from or are closely related to cultivated rice. There is suspicion that the outbreak of weedy rice in China may be related to widely grown hybrid rice due to its heterosis and the diversity of its progeny, but this notion remains unsupported by direct evidence. We screened weedy rice accessions by both genetic and molecular marker tests for the cytoplasmic male sterility (CMS) genes (Wild abortive, WA, and Boro type, BT) most widely used in the production of indica and japonica three-line hybrid rice as a diagnostic trait of direct parenthood. Sixteen weedy rice accessions of the 358 tested (4.5%) contained the CMS-WA gene; none contained the CMS-BT gene. These 16 accessions represent weedy rices recently evolved from maternal hybrid rice derivatives, given the primarily maternal inheritance of this trait. Our results provide key direct evidence that hybrid rice can be involved in the evolution of some weedy rice accessions, but is not a primary factor in the recent outbreak of weedy rice in China.

  14. Economic Valuation of Sufficient and Guaranteed Irrigation Water Supply for Paddy Farms of Guilan Province

    Directory of Open Access Journals (Sweden)

    Mohammad Kavoosi Kalashami

    2014-08-01

    Full Text Available Cultivation of the strategic crop of rice highly depends to the existence of sufficient and guaranteed irrigation water, and water shortage stresses have irreparable effects on yield and quality of productions. Decrease of the Sefidrud river inflow in Guilan province which is the main source of supplying irrigation water for 171 thousand hectares under rice cropping area of this province, has been challenged sufficient and guaranteed irrigation water supply in many regions of mentioned province. Hence, in present study estimating the value that paddy farmers place on sufficient and guaranteed irrigation water supply has been considered. Economic valuation of sufficient and guaranteed irrigation water supply improves water resource management policies in demand side. Requested data set were obtained on the base of a survey and are collected from 224 paddy farms in rural regions that faced with irrigation water shortages. Then, using open-ended valuation approach and estimation of Tobit model via ML and two stages Heckman approach, eliciting paddy farmers' willingness to pay for sufficient and guaranteed irrigation water supply has been accomplished. Results revealed that farmers in investigated regions willing to pay 26.49 percent more than present costs of providing irrigation water in order to have sufficient and guaranteed irrigation water.

  15. Reproducible and expedient rice regeneration system using in vitro ...

    African Journals Online (AJOL)

    Inevitable prerequisite for expedient regeneration in rice is the selection of totipotent explant and developing an apposite combination of growth hormones. Here, we reported a reproducible regeneration protocol in which basal segments of the stem of the in vitro grown rice plants were used as ex-plant. Using the protocol ...

  16. Resource Use Efficiency in Rice Production in Jere Local ...

    African Journals Online (AJOL)

    The study was carried-out on resource use efficiency in rice production in Jere Local Government Area of Borno State, Nigeria. Data were obtained using structured questionnaire. Five (5) wards were purposely selected out of the twelve (12) wards to reflect areas where rice is mainly grown. A total of 100 respondents were ...

  17. Aluminum and iron contents in phosphate treated swamp rice farm ...

    African Journals Online (AJOL)

    In 2006 aluminum and iron contents were determined in phosphate treated swamp rice farm of Mbiabet, Akwa Ibom State. The objectives were to determine the aluminum and iron contents, the effect of drying, phosphate and lime application in an acid sulphate soil grown to rice in Nigeria. The soil samples used were ...

  18. Can rice field channels contribute to biodiversity conservation in Southern Brazilian wetlands?

    Science.gov (United States)

    Maltchik, Leonardo; Rolon, Ana Silvia; Stenert, Cristina; Machado, Iberê Farina; Rocha, Odete

    2011-12-01

    Conservation of species in agroecosystems has attracted attention. Irrigation channels can improve habitats and offer conditions for freshwater species conservation. Two questions from biodiversity conservation point of view are: 1) Can the irrigated channels maintain a rich diversity of macrophytes, macroinvertebrates and amphibians over the cultivation cycle? 2) Do richness, abundance and composition of aquatic species change over the rice cultivation cycle? For this, a set of four rice field channels was randomly selected in Southern Brazilian wetlands. In each channel, six sample collection events were carried out over the rice cultivation cycle (June 2005 to June 2006). A total of 160 taxa were identified in irrigated channels, including 59 macrophyte species, 91 taxa of macroinvertebrate and 10 amphibian species. The richness and abundance of macrophytes, macroinvertebrates and amphibians did not change significantly over the rice cultivation cycle. However, the species composition of these groups in the irrigation channels varied between uncultivated and cultivated periods. Our results showed that the species diversity found in the irrigation channels, together with the permanence of water enables these man-made aquatic networks to function as important systems that can contribute to the conservation of biodiversity in regions where the wetlands were converted into rice fields. The conservation of the species in agriculture, such as rice field channels, may be an important alternative for biodiversity conservation in Southern Brazil, where more than 90% of wetland systems have already been lost and the remaining ones are still at high risk due to the expansion of rice production.

  19. Irrigation ponds: Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

    Institute of Scientific and Technical Information of China (English)

    DONG Bin; MAO Zhi; BROWN Larry; CHEN XiuHong; PENG LiYuan; WANG JianZhang

    2009-01-01

    Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and un-recycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China.With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious.Traditional ir-rigation and drainage systems only focus on issues concerning water quantity, i.e.the capacity of irri-gation in drought and drainage in waterlogging period, yet have no requirement on water quality im-provement, how to clean the water quality of farmland drainage through remodeling the existing irriga-tion and drainage systems has a very important realistic meaning.Pond is an important irrigation facil-ity in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use.Such water storage features of pond provide the possibility and potential capacity for drainage water treat-ment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system.To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site.The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water.Other issues, e.g.how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

  20. Irrigation ponds:Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

    Institute of Scientific and Technical Information of China (English)

    BROWN; Larry

    2009-01-01

    Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and unrecycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China. With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious. Traditional irrigation and drainage systems only focus on issues concerning water quantity, i.e. the capacity of irrigation in drought and drainage in waterlogging period, yet have no requirement on water quality improvement. how to clean the water quality of farmland drainage through remodeling the existing irrigation and drainage systems has a very important realistic meaning. Pond is an important irrigation facility in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use. Such water storage features of pond provide the possibility and potential capacity for drainage water treatment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system. To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site. The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water. Other issues, e.g. how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

  1. Armenia - Irrigation Infrastructure

    Data.gov (United States)

    Millennium Challenge Corporation — This study evaluates irrigation infrastructure rehabilitation in Armenia. The study separately examines the impacts of tertiary canals and other large infrastructure...

  2. Influence of Climate Factors on Rice Yields in Cambodia

    Directory of Open Access Journals (Sweden)

    Dek Vimean Pheakdey

    2017-12-01

    Full Text Available Temperature and precipitation have been known as the key determinant factors to affect rice production in climate change. In this study, the relationship between climate variables and rice yields during 1993–2012 in Cambodia was analyzed and evaluated. The Ordinary Least Squares analysis was applied to examine the relationship of three climate variables (TCV including maximum temperature, minimum temperature and rainfall against seasonal rice yields. By this period, a remarkable increasing trend of annual temperature was observed whilst rainfall was not significantly changed. The TCV explains approximately 63% and 56% of the variability of rice yields in wet and dry seasons, respectively. It is found that in Cambodia, non-climate factors such as fertilizers, water, cultivars, and soil fertility cause 40% variation to rice yields, whereas the remaining 60% can be influenced by climate variability. The levels of temperature difference (LTD between maximum and minimum temperatures of the wet season (WS and dry season (DS were 7.0 and 8.6 oC, respectively. The lower value of LTD may cause the reduction of rice in WS (2.2 tons/ha as compared to that of DS (3.0 tons/ha. Rice yield has increased 50.5% and 33.8% in DS and WS, respectively, may due to the improvement of rice cultivation practices in Cambodia such as the better use of fertilizers, pest and weed control, and irrigation, and more effective rice cultivated protocol, as the increased trend of temperature may detrimentally affect rice yield. The breeding of heat and drought tolerance rice varieties and development of irrigation system are effective to reduce the negative influence from climate change to rice production in Cambodia.

  3. Glufosinate herbicide-tolerant (LibertyLink) rice vs. conventional rice in diets for growing-finishing swine.

    Science.gov (United States)

    Cromwell, G L; Henry, B J; Scott, A L; Gerngross, M F; Dusek, D L; Fletcher, D W

    2005-05-01

    Genetically modified (GM) rice (LibertyLink, event LLRICE62) that is tolerant to glufosinate ammonium (Liberty) herbicide was compared with a near-isogenic (NI) conventional medium-grain brown rice (cultivar, Bengal) and a commercially milled long-grain brown rice in diets for growing-finishing pigs. The GM and NI rice were grown in 2000. The GM rice was from fields treated (GM+) or not treated (GM-) with glufosinate herbicide. The GM- and NI rice were grown using herbicide regimens typical of southern United States rice production practices. The four rice grains were similar in composition. Growing-finishing pigs (n = 96) were fed fortified rice-soybean meal diets containing the four different rice grains from 25 to 106 kg BW. Diets contained 0.99% lysine initially (growing phase), with lysine decreased to 0.80% (early finishing phase) and 0.65% (late finishing phase), when pigs reached 51 and 77 kg, respectively. The percentage of rice in the four diets was constant during each of the three phases (72.8, 80.0, and 85.8% for the growing, early-finishing, and late-finishing phases, respectively). There were six pen replicates (three pens of barrows and three pens of gilts) and four pigs per pen for each dietary treatment. All pigs were slaughtered at the termination of the study to collect carcass data. At the end of the 98-d experiment, BW gain, feed intake (as-fed basis), and feed:gain ratio did not differ (P > 0.05) for pigs fed the GM+ vs. conventional rice diets, but growth performance traits of pigs fed the GM+ rice diets were superior (P glufosinate herbicide-tolerant rice was similar in composition and nutritional value to conventional rice for growing-finishing pigs.

  4. Stakeholder analysis in the management of irrigation in Kampili area

    Science.gov (United States)

    Jumiati; Ali, M. S. S.; Fahmid, I. M.; Mahyuddin

    2018-05-01

    Irrigation has appreciable contribution in building food security, particularly rice crops. This study aims to analyze the role of stakeholders involved in distributing of irrigation water. The study was conducted in the Kampili Irrigation Area in South Sulawesi Province Indonesia, the data were obtained through observation and interviews with stakeholders involved, and analysed by stakeholder analysis, based on the interests and power held by the actors. This analysis is intended to provide an optimal picture of the expected role of each stakeholder in the management of irrigation resources. The results show that there were many stakeholders involved in irrigation management. In the arrangement of irrigation distribution there was overlapping authority of the stakeholders to its management, every stakeholder had different interests and power between each other. The existence have given positive and negative values in distributing irrigation water management, then in the stakeholder collaboration there was contestation between them. This contestation took place between the agriculture department, PSDA province, the Jeneberang River Region Hall, the Farmers Group and the P3A.

  5. Crop performance, nitrogen and water use in flooded and aerobic rice

    NARCIS (Netherlands)

    Belder, P.; Bouman, B.A.M.; Spiertz, J.H.J.; Peng, S.; Castañeda, A.R.; Visperas, R.M.

    2005-01-01

    Abstract Irrigated aerobic rice is a new system being developed for lowland areas with water shortage and for favorable upland areas with access to supplementary irrigation. It entails the cultivation of nutrient-responsive cultivars in nonsaturated soil with sufficient external inputs to reach

  6. Production of pulse in mono-cropped rice system in the coastal region of Eastern India

    International Nuclear Information System (INIS)

    Khan, A.R.; Nanda, P.; Chandra, Dinesh; Ghorai, A.K.; Behera, M.S.

    2001-04-01

    This experiment was undertaken with an objective to increase the yield of black-gram leguminous pulse crop through optimal doses of phosphatic fertilizer with supplemental irrigation in mono-cropped rice-fallow regions of India. Irrigation and phosphorus fertilizer application were introduced for enhancing productivity of black-gram to provide better returns to available water resources

  7. Nursery cultural practices to achieve targets: A case study in western larch irrigation

    Science.gov (United States)

    Anthony S. Davis; Robert F. Keefe

    2011-01-01

    Nursery cultural practices are used to help growers achieve pre-determined size and physiological targets for seedlings. In that regard, irrigation is used to accelerate or slow growth and as a trigger for changing growth phase. In a case study highlighting the effects of irrigation on seedling development, western larch (Larix occidentalis Nutt.) seedlings were grown...

  8. Irrigation and Autocracy

    DEFF Research Database (Denmark)

    Bentzen, Jeanet Sinding; Kaarsen, Nicolai; Wingender, Asger Moll

    2017-01-01

    . We argue that the effect has historical origins: irrigation allowed landed elites in arid areas to monopolize water and arable land. This made elites more powerful and better able to oppose democratization. Consistent with this conjecture, we show that irrigation dependence predicts land inequality...

  9. Effective colostomy irrigation.

    Science.gov (United States)

    Mazier, W P; Dignan, R D; Capehart, R J; Smith, B G

    1976-06-01

    The ultimate goal of the cone method of colostomy irrigation is to return patients with colostomies to their former role in society with confidence in themselves to the extent that having a colostomy is not considered a handicap. The results have generally been excellent. We believe all patients with stomas should be afforded the opportunity to attempt colostomy irrigation.

  10. An overview of global rice production, supply, trade, and consumption.

    Science.gov (United States)

    Muthayya, Sumithra; Sugimoto, Jonathan D; Montgomery, Scott; Maberly, Glen F

    2014-09-01

    Rice is the staple food for over half the world's population. Approximately 480 million metric tons of milled rice is produced annually. China and India alone account for ∼50% of the rice grown and consumed. Rice provides up to 50% of the dietary caloric supply for millions living in poverty in Asia and is, therefore, critical for food security. It is becoming an important food staple in both Latin America and Africa. Record increases in rice production have been observed since the start of the Green Revolution. However, rice remains one of the most protected food commodities in world trade. Rice is a poor source of vitamins and minerals, and losses occur during the milling process. Populations that subsist on rice are at high risk of vitamin and mineral deficiency. Improved technologies to fortify rice have the potential to address these deficiencies and their associated adverse health effects. With the rice industry consolidating in many countries, there are opportunities to fortify a significant share of rice for distribution or for use in government safety net programs that target those most in need, especially women and children. Multisectoral approaches are needed for the promotion and implementation of rice fortification in countries. © 2014 New York Academy of Sciences.

  11. NUTRIENT CONTENT IN SUNFLOWERS IRRIGATED WITH OIL EXPLORATION WATER

    Directory of Open Access Journals (Sweden)

    ADERVAN FERNANDES SOUSA

    2016-01-01

    Full Text Available Irrigation using produced water, which is generated during crude oil and gas recovery and treated by the exploration industry, could be an option for irrigated agriculture in semiarid regions. To determine the viability of this option, the effects of this treated water on the nutritional status of plants should be assessed. For this purpose, we examined the nutritional changes in sunflowers after they were irrigated with oil - produced water and the effects of this water on plant biomass and seed production. The sunflower cultivar BRS 321 was grown for three crop cycles in areas irrigated with filtered produced water (FPW, reverse osmosis - treated produced water (OPW, or ground water (GW. At the end of each cycle, roots, shoots, and seeds were collected to examine their nutrient concentrations. Produced water irrigation affected nutrient accumulation in the sunflower plants. OPW irrigation promoted the accumulation of Ca, Na, N, P, and Mg. FPW irrigation favored the accumulation of Na in both roots and shoots, and biomass and seed production were negatively affected. The Na in the shoots of plants irrigated with FPW increased throughout the three crop cycles. Under controlled conditions, it is possible to reuse reverse osmosis - treated produced water in agriculture. However, more long - term research is needed to understand its cumulative effects on the chemical and biological properties of the soil and crop production.

  12. Problems of irrigated agriculture in saline groundwater areas: farmers' perceptions

    International Nuclear Information System (INIS)

    Ahmad, S.; Yasin, M.; Ahmad, M.M.; Hussain, Z.; Khan, Z.; Akbar, G.

    2005-01-01

    A research study was conducted using participatory interactive dialogue in the brackish groundwater area of Mona SCARP-II, Bhalwal district Sargodha, Pakistan. The Participatory Rural Appraisal (PRA) was conducted in thirteen villages to identify macro- and micro-level issues related to irrigated agriculture in saline groundwater areas. SCARP tube wells have been abandoned or few have been handed over to farmers' organizations. Groundwater in the Indus basin contributes around 35% to the total water available for agriculture. Water quality of 60% area of the Indus basin is marginal to brackish. Minimum land holding of cultivated land in the elected villages varied from 0.10 to 4 ha. The maximum land holding of cultivated area in selected villages varied for 6 to 50 ha. However, the average size of farm was around 4 ha. The average salt-affected area per household was 17% of the total cultivated area. The salt-affected lands in 8 villages out of 13 were barren, where mainly rice crop is grown during kharif season. About 67% farms had access to conjunctive use of water, as water from both canal and private tube wells is available. In addition, 10% farms were having tube well water only. Therefore, 77% farms are having access to the groundwater. According to the farmers' perceptions, 100% villages have fresh groundwater to a depth of 7.5 m and 62% villages had depth ranging from 15-30 m. Furthermore, in all thirteen selected villages, groundwater quality beyond 30 m depth was brackish. Laboratory analysis confirmed the farmer's perception that groundwater quality is a function of depth. About 92% farmers groups indicated that non-availability and high price of inputs was a major problem. The second major issue was related to the shortage of canal water supplies and 77% villages are facing this problem. Moreover, 31% farmers' groups of selected villages indicated that water logging and salinity are the major concerns affecting agricultural productivity. This figure is

  13. Optimizing Greenhouse Rice Production: Summary of Recommendations

    OpenAIRE

    Eddy, Robert; Acosta, Kevin; Liu, Yisi; Russell, Michael

    2016-01-01

    This publication provides a single-page chart summarizing our protocols for growing Rice (japonica). Split into three production goals, recommendations are given for photoperiod, temperature, lighting, container, root medium, planting density, irrigation, fertilization, algae control and fungus gnat control. This version updates our fertilization frequency, pot size, root medium and algae control recommendations. This document summarizes a series of questions and answers originally posted ...

  14. Study of arsenic accumulation in rice and evaluation of protective effects of Chorchorus olitorius leaves against arsenic contaminated rice induced toxicities in Wistar albino rats.

    Science.gov (United States)

    Hosen, Saeed Mohammed Imran; Das, Dipesh; Kobi, Rupkanowar; Chowdhury, Dil Umme Salma; Alam, Md Jibran; Rudra, Bashudev; Bakar, Muhammad Abu; Islam, Saiful; Rahman, Zillur; Al-Forkan, Mohammad

    2016-10-14

    In the present study, we investigated the arsenic accumulation in different parts of rice irrigated with arsenic contaminated water. Besides, we also evaluated the protective effects of Corchorus olitorius leaves against arsenic contaminated rice induced toxicities in animal model. A pot experiment was conducted with arsenic amended irrigation water (0.0, 25.0, 50.0 and 75.0 mg/L As) to investigate the arsenic accumulation in different parts of rice. In order to evaluate the protective effects of Corchorus olitorius leaves, twenty Wistar albino rats were divided into four different groups. The control group (Group-I) was supplied with normal laboratory pellets while groups II, III, and IV received normal laboratory pellets supplemented with arsenic contaminated rice, C. olitorius leaf powder (4 %), arsenic contaminated rice plus C. olitorius leaf powder (4 %) respectively. Different haematological parameters and serum indices were analyzed to evaluate the protective effects of Corchorus olitorius leaves against arsenic intoxication. To gather more supportive evidences of Corchorus olitorius potentiality against arsenic intoxication, histopathological analysis of liver, kidney, spleen and heart tissues was also performed. From the pot experiment, we have found a significant (p ≤ 0.05) increase of arsenic accumulation in different parts of rice with the increase of arsenic concentrations in irrigation water and the trend of accumulation was found as root > straw > husk > grain. Another part of the experiment revealed that supplementation of C. olitorius leaves with arsenic contaminated rice significantly (p rice induced toxicities. Arsenic accumulation in different parts of rice increased dose-dependently. Hence, for irrigation purpose arsenic contaminated water cannot be used. Furthermore, arsenic contaminated rice induced several toxicities in animal model, most of which could be minimized with the food supplementation of Corchorus olitorius

  15. (PGMS) rice

    African Journals Online (AJOL)

    user

    2011-04-18

    Apr 18, 2011 ... tics, led us to predict that pollen cell abortion in this type of rice when ... averages of natural day-light-lengths and temperatures were used. A natural long ... blocks were allowed to grow under natural growth conditions (which.

  16. Closing the irrigation deficit in Cambodia: Implications for transboundary impacts on groundwater and Mekong River flow

    Science.gov (United States)

    Erban, Laura E.; Gorelick, Steven M.

    2016-04-01

    Rice production in Cambodia, essential to food security and exports, is largely limited to the wet season. The vast majority (96%) of land planted with rice during the wet season remains fallow during the dry season. This is in large part due to lack of irrigation capacity, increases in which would entail significant consequences for Cambodia and Vietnam, located downstream on the Mekong River. Here we quantify the extent of the dry season ;deficit; area in the Cambodian Mekong River catchment, using a recent agricultural survey and our analysis of MODIS satellite data. Irrigation of this land for rice production would require a volume of water up to 31% of dry season Mekong River flow to Vietnam. However, the two countries share an aquifer system in the Mekong Delta, where irrigation demand is increasingly met by groundwater. We estimate expansion rates of groundwater-irrigated land to be >10% per year in the Cambodian Delta using LANDSAT satellite data and simulate the effects of future expansion on groundwater levels over a 25-year period. If groundwater irrigation continues to expand at current rates, the water table will drop below the lift limit of suction pump wells, used for domestic supply by >1.5 million people, throughout much of the area within 15 years. Extensive groundwater irrigation jeopardizes access for shallow domestic water supply wells, raises the costs of pumping for all groundwater users, and may exacerbate arsenic contamination and land subsidence that are already widespread hazards in the region.

  17. Water relations of field-grown grapevines in the São Francisco Valley, Brazil, under different rootstocks and irrigation strategies Relações hídricas de videiras cultivadas no Vale do São Francisco sob diferente porta-enxertos e estratégias de irrigação

    Directory of Open Access Journals (Sweden)

    Claudia Rita de Souza

    2009-08-01

    Full Text Available There is an increased demand for high quality winegrapes in the São Francisco Valley, a new wine producing area in Brazil. As the grape quality is closely linked to the soil water status, understanding the effects of rootstock and irrigation management on grapevine water relations is essential to optimize yield and quality. This study was carried out to investigate the effects of irrigation strategies and rootstocks on water relations and scion vigour of field-grown grapevines in Petrolina, Pernambuco state, Brazil. The cultivars used as scions are Moscato Canelli and Syrah, both grafted onto IAC 572 and 1103 Paulsen rootstocks. The following water treatments were used: deficit irrigation, with holding water after veraison; and partial root-zone drying, supplying (100% of crop evapotranspiration of the water loss to only one side of the root system after fruit set, alternating the sides periodically (about 24 days. In general, all treatments had values of pre-dawn leaf water potential higher than -0.2 MPa, suggesting absence of water stress. The vine water status was more affected by rootstock type than irrigation strategies. Both cultivars grafted on IAC 572 had the highest values of midday leaf water potential and stem water potential, measured on non-transpiring leaves, which were bagged with both plastic sheet and aluminum foil at least 1 h before measurements. For both cultivars, the stomatal conductance (g s, transpiration (E and leaf area index (LAI were also more affected by roostsotck type than by irrigation strategies. The IAC 572 rootstock presented higher g s, E and LAI than the 1103 Paulsen. Differences in vegetative vigor of the scion grafted onto IAC 572 rootstocks were related to its higher leaf specific hydraulic conductance and deeper root system as compared to the 1103 Paulsen, which increased the water-extraction capability, resulting in a better vine water status.Existe aumento na demanda por vinhos de alta qualidade no

  18. Chemometric classification of pigmented rice varieties based on antioxidative properties in relation to color

    Directory of Open Access Journals (Sweden)

    Phaiwan Pramai

    2016-10-01

    Full Text Available The pigmented Thai rice varieties including red and black color and non-pigmented rice (white collected from different growth sites in the north of Thailand and were determined for color and antioxidant properties. Anthocyanins were the major compound in group of black rice (21.15-441.96 mg/100 g rice. Total phenolic, flavonoid, and -tocopherol contents were highest in the black rice followed by red rice and antioxidant capacities were predominant in pigmented varieties. Black rice grown in mountainous area presented the highest antioxidant activity compared to the other growing locations. The color parameters, especially L* value presented the negative correlations with antioxidant parameters, while the antioxidant contents, excepted -oryzanol content had significant correlation with antioxidant capacities. Pigmented rice varieties could be clearly classified into 4 groups using PCA and HCA, which provided a good indicator to classify pigmented rice varieties based on color and antioxidative properties.

  19. Influence of composted organic waste and urea fertilization on rice ...

    African Journals Online (AJOL)

    The field experiment was conducted at the University of Ghana's Soil and Irrigation Research Centre - Kpong during 2014 and 2015 cropping seasons to evaluate the influence of composted organic waste and urea fertilization on rice yield, Nitrogen-use efficiency and soil chemical characteristics. The study was laid out in a ...

  20. Can deficit irrigation techniques be used to enhance phosphorus and water use efficiency and benefit crop yields?

    Science.gov (United States)

    Wright, Hannah R.; Dodd, Ian C.; Blackwell, Martin S. A.; Surridge, Ben W. J.

    2015-04-01

    Soil drying and rewetting (DRW) affects the forms and availability of phosphorus (P). Water soluble P has been reported to increase 1.8- to 19-fold after air-drying with the majority of the increase (56-100%) attributable to organic P. Similarly, in two contrasting soil types DRW increased concentrations of total P and reactive P in leachate, likely due to enhanced P mineralisation and physiochemical processes causing detachment of soil colloids, with faster rewetting rates related to higher concentrations of P. The intensity of drying as well as the rate of rewetting influences organic and inorganic P cycling. How these dynamics are driven by soil water status, and impact crop P acquisition and growth, remains unclear. Improving P and water use efficiencies and crop yields is globally important as both P and water resources become increasingly scarce, whilst demand for food increases. Irrigation supply below the water requirement for full crop evapotranspiration is employed by agricultural practitioners where water supply is limited. Regulated deficit irrigation describes the scheduling of water supply to correspond to the times of highest crop demand. Alternate wetting and drying (AWD) is applied in lowland irrigated rice production to avoid flooding at certain times of crop development, and has benefited P nutrition and yields. This research aims to optimise the benefits of P availability and uptake achieved by DRW by guiding deficit irrigation management strategies. Further determination of underlying processes driving P cycling at fluctuating soil moisture status is required. Presented here is a summary of the literature on DRW effects on soil P availability and plant P uptake and partitioning, in a range of soil types and cropping systems, with emphasis on alternate wetting and drying irrigation (AWD) compared to continuous flooding in lowland irrigated rice production. Soil water contents and matric potentials, and effects on P dynamics, are highly variable

  1. The limit of irrigation adaption due to the inter-crop conflict of water use under changing climate and landuse

    Science.gov (United States)

    Okada, M.; Iizumi, T.; Sakamoto, T.; Kotoku, M.; Sakurai, G.; Nishimori, M.

    2017-12-01

    Replacing rainfed cropping system by irrigated one is assumed to be an effective measure for climate change adaptation in agriculture. However, in many agricultural impact assessments, future irrigation scenarios are externally given and do not consider variations in the availability of irrigation water under changing climate and land use. Therefore, we assess the potential effects of adaption measure expanding irrigated area under climate change by using a large-scale crop-river coupled model, CROVER [Okada et al. 2015, JAMES]. The CROVER model simulates the large-scale terrestrial hydrological cycle and crop growth depending on climate, soil properties, landuse, crop cultivation management, socio-economic water demand, and reservoir operation management. The bias-corrected GCMs outputs under the RCP 8.5 scenario were used. The future expansion of irrigation area was estimated by using the extrapolation method based on the historical change in irrigated and rainfed areas. As the results, the irrigation adaptation has only a limited effect on the rice production in East Asia due to the conflict of water use for irrigation with the other crops, whose farmlands require unsustainable water extraction with the excessively expanding irrigated area. In contrast, the irrigation adaptation benefits maize production in Europe due to the little conflict of water use for irrigation. Our findings suggest the importance of simulating the river water availability and crop production in a single model for the more realistic assessment in the irrigation adaptation potential effects of crop production under changing climate and land use.

  2. The impact of herbicide-resistant rice technology on phenotypic diversity and population structure of United States weedy rice.

    Science.gov (United States)

    Burgos, Nilda Roma; Singh, Vijay; Tseng, Te Ming; Black, Howard; Young, Nelson D; Huang, Zhongyun; Hyma, Katie E; Gealy, David R; Caicedo, Ana L

    2014-11-01

    The use of herbicide-resistant (HR) Clearfield rice (Oryza sativa) to control weedy rice has increased in the past 12 years to constitute about 60% of rice acreage in Arkansas, where most U.S. rice is grown. To assess the impact of HR cultivated rice on the herbicide resistance and population structure of weedy rice, weedy samples were collected from commercial fields with a history of Clearfield rice. Panicles from each weedy type were harvested and tested for resistance to imazethapyr. The majority of plants sampled had at least 20% resistant offspring. These resistant weeds were 97 to 199 cm tall and initiated flowering from 78 to 128 d, generally later than recorded for accessions collected prior to the widespread use of Clearfield rice (i.e. historical accessions). Whereas the majority (70%) of historical accessions had straw-colored hulls, only 30% of contemporary HR weedy rice had straw-colored hulls. Analysis of genotyping-by-sequencing data showed that HR weeds were not genetically structured according to hull color, whereas historical weedy rice was separated into straw-hull and black-hull populations. A significant portion of the local rice crop genome was introgressed into HR weedy rice, which was rare in historical weedy accessions. Admixture analyses showed that HR weeds tend to possess crop haplotypes in the portion of chromosome 2 containing the ACETOLACTATE SYNTHASE gene, which confers herbicide resistance to Clearfield rice. Thus, U.S. HR weedy rice is a distinct population relative to historical weedy rice and shows modifications in morphology and phenology that are relevant to weed management. © 2014 American Society of Plant Biologists. All Rights Reserved.

  3. Does morphological and anatomical plasticity during the vegetative stage make wheat more tolerant of water deficit stress than rice?

    NARCIS (Netherlands)

    Kadam, N.N.; Yin, X.; Bindraban, P.S.; Struik, P.C.; Jagadish, K.S.V.

    2015-01-01

    Water scarcity and the increasing severity of water deficit stress are major challenges to sustaining irrigated rice (Oryza sativa) production. Despite the technologies developed to reduce the water requirement, rice growth is seriously constrained under water deficit stress compared with other

  4. Quality and Quantity Evaluations of Shade Grown Forages

    Science.gov (United States)

    K. P. Ladyman; M. S. Kerley; R. L. Kallenbach; H. E. Garrett; J. W. Van Sambeek; N. E. Navarrete-Tindall

    2003-01-01

    Seven legumes were grown during the summer-fall of 2000, at the Horticulture and Agroforestry Research Center (39? 01 ' N, 92? 46' W) near New Franklin, MO. The forages were grown in 7.5L white pots placed on light-colored gravel either under full sunlight, 45% sunlight, or 20% sunlight created by a shade cloth over a rectangular frame. Drip irrigation was...

  5. Produção e qualidade do meloeiro cultivado com filmes plásticos em respostas à lâmina de irrigação Yield and quality of the melon fruit grown with plastic films in response to irrigation depth

    Directory of Open Access Journals (Sweden)

    Daniel da Costa Dantas

    2011-09-01

    the yield and fruit quality of yellow melon grown with four irrigation depths (L1 - 100%, L2 - 91%, L3 - 82%, L4 - 72% of the standard depth of 452 mm which was determined by the methodology of the FAO Kc dual and tree types of polyethylene film (white-black, silver-black, black-black used for the soil cover, compared with cultivation without coverage. Was used the randomized block design with split plot into 4 x 4, and four replications. The use of polyethylene films provided a significant increase in yield, and the increase of fruit weight by 20% on average, compared to treatment without coverage; the polyethylene film of white-black and black-black were better in relation to the silver-black color; the standard depth of 452 mm can be reduced by 28% without yield reduction even with the average fruit weight decrease by 11%; the concentration of soluble solids decreased as the irrigation was reduced due to heavy pest attack.

  6. Golden Rice is an effective source of vitamin A.

    Science.gov (United States)

    Tang, Guangwen; Qin, Jian; Dolnikowski, Gregory G; Russell, Robert M; Grusak, Michael A

    2009-06-01

    Genetically engineered "Golden Rice" contains up to 35 microg beta-carotene per gram of rice. It is important to determine the vitamin A equivalency of Golden Rice beta-carotene to project the potential effect of this biofortified grain in rice-consuming populations that commonly exhibit low vitamin A status. The objective was to determine the vitamin A value of intrinsically labeled dietary Golden Rice in humans. Golden Rice plants were grown hydroponically with heavy water (deuterium oxide) to generate deuterium-labeled [2H]beta-carotene in the rice grains. Golden Rice servings of 65-98 g (130-200 g cooked rice) containing 0.99-1.53 mg beta-carotene were fed to 5 healthy adult volunteers (3 women and 2 men) with 10 g butter. A reference dose of [13C10]retinyl acetate (0.4-1.0 mg) in oil was given to each volunteer 1 wk before ingestion of the Golden Rice dose. Blood samples were collected over 36 d. Our results showed that the mean (+/-SD) area under the curve for the total serum response to [2H]retinol was 39.9 +/- 20.7 microg x d after the Golden Rice dose. Compared with that of the [13C10]retinyl acetate reference dose (84.7 +/- 34.6 microg x d), Golden Rice beta-carotene provided 0.24-0.94 mg retinol. Thus, the conversion factor of Golden Rice beta-carotene to retinol is 3.8 +/- 1.7 to 1 with a range of 1.9-6.4 to 1 by weight, or 2.0 +/- 0.9 to 1 with a range of 1.0-3.4 to 1 by moles. Beta-carotene derived from Golden Rice is effectively converted to vitamin A in humans. This trial was registered at clinicaltrials.gov as NCT00680355.

  7. Emergy Evaluation of a Production and Utilization Process of Irrigation Water in China

    Directory of Open Access Journals (Sweden)

    Dan Chen

    2013-01-01

    Full Text Available Sustainability evaluation of the process of water abstraction, distribution, and use for irrigation can contribute to the policy of decision making in irrigation development. Emergy theory and method are used to evaluate a pumping irrigation district in China. A corresponding framework for its emergy evaluation is proposed. Its emergy evaluation shows that water is the major component of inputs into the irrigation water production and utilization systems (24.7% and 47.9% of the total inputs, resp. and that the transformities of irrigation water and rice as the systems’ products (1.72E+05 sej/J and 1.42E+05 sej/J, resp.; sej/J = solar emjoules per joule represent their different emergy efficiencies. The irrigated agriculture production subsystem has a higher sustainability than the irrigation water production subsystem and the integrated production system, according to several emergy indices: renewability ratio (%R, emergy yield ratio (EYR, emergy investment ratio (EIR, environmental load ratio (ELR, and environmental sustainability index (ESI. The results show that the performance of this irrigation district could be further improved by increasing the utilization efficiencies of the main inputs in both the production and utilization process of irrigation water.

  8. Emergy evaluation of a production and utilization process of irrigation water in China.

    Science.gov (United States)

    Chen, Dan; Luo, Zhao-Hui; Chen, Jing; Kong, Jun; She, Dong-Li

    2013-01-01

    Sustainability evaluation of the process of water abstraction, distribution, and use for irrigation can contribute to the policy of decision making in irrigation development. Emergy theory and method are used to evaluate a pumping irrigation district in China. A corresponding framework for its emergy evaluation is proposed. Its emergy evaluation shows that water is the major component of inputs into the irrigation water production and utilization systems (24.7% and 47.9% of the total inputs, resp.) and that the transformities of irrigation water and rice as the systems' products (1.72E + 05 sej/J and 1.42E + 05 sej/J, resp.; sej/J = solar emjoules per joule) represent their different emergy efficiencies. The irrigated agriculture production subsystem has a higher sustainability than the irrigation water production subsystem and the integrated production system, according to several emergy indices: renewability ratio (%R), emergy yield ratio (EYR), emergy investment ratio (EIR), environmental load ratio (ELR), and environmental sustainability index (ESI). The results show that the performance of this irrigation district could be further improved by increasing the utilization efficiencies of the main inputs in both the production and utilization process of irrigation water.

  9. Living with less water: development of viable adaptation options for Riverina irrigators

    NARCIS (Netherlands)

    Gaydon, D.S.

    2012-01-01

    In Australia, the best use of limited national water resources continues to be a major political and scientific issue. Average water allocations for rice-cereal irrigation farmers in the Riverina region have been drastically reduced since 1998 as a consequence of high rainfall variability and

  10. Drip irrigation using a PLC based adaptive irrigation system

    OpenAIRE

    Shahidian, S.; Serralheiro, R. P.; Teixeira, J. L.; Santos, F. L.; Oliveira, M. R. G.; Costa, J. L.; Toureiro, C.; Haie, Naim; Machado, R. M.

    2009-01-01

    Most of the water used by man goes to irrigation. A major part of this water is used to irrigate small plots where it is not feasible to implement full-scale Evapotranspiration based irrigation controllers. During the growth season crop water needs do not remain constant and varies depending on the canopy, growth stage and climate conditions such as temperature, wind, relative humidity and solar radiation. Thus, it is necessary to find an economic irrigation controller that can adapt the dail...

  11. Low-level maternal methylmercury exposure through rice ingestion and potential implications for offspring health

    Energy Technology Data Exchange (ETDEWEB)

    Rothenberg, Sarah E., E-mail: rothenberg.sarah@gmail.com [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Feng Xinbin, E-mail: fengxinbin@vip.skleg.cn [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China); Li Ping [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Lu, Guiyang 550002 (China)

    2011-04-15

    Fish consumption is considered the primary pathway for MeHg (MeHg) exposure; however, MeHg exposure also occurs through rice ingestion. Rice is grown in an aquatic environment and although documented MeHg concentrations in rice are lower compared to fish tissue, human exposures exceed international guidelines in some regions where rice is a staple food and rice MeHg levels are elevated. Studies concerning human health exposure to MeHg should also include populations where maternal MeHg exposure occurs through ingestion of rice. Rice does not contain long-chain polyunsaturated fatty acids, which are associated with confounding developmental outcomes in offspring. Rice is also a staple food for more than half the world's population; therefore, it is critical to investigate the potential health risks of maternal ingestion of rice to the developing fetus, the most susceptible population to the deleterious effects of MeHg. Data concerning MeHg in rice are reviewed and micronutrients in rice are discussed. - Research highlights: > Maternal methylmercury exposure through rice may be important. > Rice does not contain the same micronutrients as fish, but may contain methylmercury. > Effects to offspring from methylmercury without beneficial micronutrients are unknown. - Studies concerning maternal methylmercury exposure and cognitive outcomes for offspring should include populations where rice ingestion is the primary methylmercury exposure pathway.

  12. Low-level maternal methylmercury exposure through rice ingestion and potential implications for offspring health

    International Nuclear Information System (INIS)

    Rothenberg, Sarah E.; Feng Xinbin; Li Ping

    2011-01-01

    Fish consumption is considered the primary pathway for MeHg (MeHg) exposure; however, MeHg exposure also occurs through rice ingestion. Rice is grown in an aquatic environment and although documented MeHg concentrations in rice are lower compared to fish tissue, human exposures exceed international guidelines in some regions where rice is a staple food and rice MeHg levels are elevated. Studies concerning human health exposure to MeHg should also include populations where maternal MeHg exposure occurs through ingestion of rice. Rice does not contain long-chain polyunsaturated fatty acids, which are associated with confounding developmental outcomes in offspring. Rice is also a staple food for more than half the world's population; therefore, it is critical to investigate the potential health risks of maternal ingestion of rice to the developing fetus, the most susceptible population to the deleterious effects of MeHg. Data concerning MeHg in rice are reviewed and micronutrients in rice are discussed. - Research highlights: → Maternal methylmercury exposure through rice may be important. → Rice does not contain the same micronutrients as fish, but may contain methylmercury. → Effects to offspring from methylmercury without beneficial micronutrients are unknown. - Studies concerning maternal methylmercury exposure and cognitive outcomes for offspring should include populations where rice ingestion is the primary methylmercury exposure pathway.

  13. Detection and assessment of flood susceptible irrigation networks in Licab, Nueva Ecija, Philippines using LiDAR DTM

    Science.gov (United States)

    Alberto, R. T.; Hernando, P. J. C.; Tagaca, R. C.; Celestino, A. B.; Palado, G. C.; Camaso, E. E.; Damian, G. B.

    2017-09-01

    Climate change has wide-ranging effects on the environment and socio-economic and related sectors which includes water resources, agriculture and food security, human health, terrestrial ecosystems, coastal zones and biodiversity. Farmers are under pressure to the changing weather and increasing unpredictable water supply. Because of rainfall deficiencies, artificial application of water has been made through irrigation. Irrigation is a basic determinant of agriculture because its inadequacies are the most powerful constraints on the increase of agricultural production. Irrigation networks are permanent and temporary conduits that supply water to agricultural areas from an irrigation source. Detection of irrigation networks using LiDAR DTM, and flood susceptible assessment of irrigation networks could give baseline information on the development and management of sustainable agriculture. Map Gully Depth (MGD) in Whitebox GAT was used to generate the potential irrigation networks. The extracted MGD was overlaid in ArcGIS as guide in the digitization of potential irrigation networks. A flood hazard map was also used to identify the flood susceptible irrigation networks in the study area. The study was assessed through field validation of points which were generated using random sampling method. Results of the study showed that most of the detected irrigation networks have low to moderate susceptibility to flooding while the rest have high susceptibility to flooding which is due to shifting weather. These irrigation networks may cause flood when it overflows that could also bring huge damage to rice and other agricultural areas.

  14. Optimization of planting pattern plan in Logung irrigation area using linear program

    Science.gov (United States)

    Wardoyo, Wasis; Setyono

    2018-03-01

    Logung irrigation area is located in Kudus Regency, Central Java Province, Indonesia. Irrigation area with 2810 Ha of extent is getting water supply from Logung dam. Yet, the utilization of water at Logung dam is not optimal and the distribution of water is still not evenly distributed. Therefore, this study will discuss about the optimization of irrigation water utilization based on the beginning of plant season. This optimization begins with the analysis of hydrology, climatology and river discharge in order to determine the irrigation water needs. After determining irrigation water needs, six alternatives of planting patterns with the different early planting periods, i.e. 1st November, 2nd November, 3rd November, 1st December, 2nd December, and 3rd December with the planting pattern of rice-secondary crop-sugarcane is introduced. It is continued by the analysis of water distribution conducted using linear program assisted by POM-Quantity method for Windows 3 with the reliable discharge limit and the available land area. Output of this calculation are to determine the land area that can be planted based on the type of plant and growing season, and to obtaine the profits of harvest yields. Based on the optimum area of each plant species with 6 alternatives, the most optimum area was obtained at the early planting periods on 3rd December with the production profit of Rp 113.397.338.854,- with the planting pattern of rice / beans / sugarcane-rice / beans / sugarcane-beans / sugarcane.

  15. Comparative effects of partial root-zone drying and deficit irrigation on nitrogen uptake in potatoes (Solanum tuberosum L.)

    DEFF Research Database (Denmark)

    Wang, Huiqun; Liu, Fulai; Andersen, Mathias Neumann

    2009-01-01

    The effects of partial root-zone drying (PRD) as compared with deficit irrigation (DI) and full irrigation (FI) on nitrogen (N) uptake and partitioning in potato (Solanum tuberosum L.) were investigated. Potato plants were grown in split-root pots and were exposed to FI, PRD, and DI treatments...

  16. EFFECT OF GROWTH PROMOTOR AND BIOPROTECTOR ON THE DEVELOPMENT OF IRRIGATED RICE AND BROWN SPOT INCIDENCE USO DE PROMOTOR DE CRESCIMENTO E DE BIOPROTETOR NA CULTURA DO ARROZ IRRIGADO E SEU EFEITO SOBRE A INCIDÊNCIA DA MANCHA-DE-GRÃOS

    Directory of Open Access Journals (Sweden)

    Rodrigo Fascin Berni

    2007-09-01

    Full Text Available

    Two experiments were carried out to evaluate the effect of two commercial products, one containing plant-growth promoting rhizobacteria (PGPR and micorrhizae, and the other containing micronutrients and aminoacids, on the development of irrigated rice. One kilogram of the biological product Biosol (trade mark was added to the seeds at sowing time (1kg / ha and the biofertilizer Greensol (trade mark was sprayed by airplane (200 ml / ha in association with fungicides, when 5% of panicles had been emitted. The treatments used were T1: Control; T2: Greensol; T3: Biosol + Greensol and T4: Biosol. Five parameters were evaluated: number of shoots per meter, dry weight 90 days after sowing, grain yield, empty grains percentage and incidence of brown spot disease (Helminthosporium oryzae Breda de Haan. Number of shoots per meter was uniform in all treatments. Grouped analysis indicated superiority of all treatments with Biosol over the control for the parameters of dry weight of plants and roots. Treatments T3 and T4 presented superior yields. In these treatments empty grain percentage was lower than the control. Brown spot severity index indicated that all treatments were better than control and T3 and T4 treatments had the lowest disease index.

    KEY-WORDS: Helminthosporium oryzae; Oryza sativa; disease control; rice.

    Foram conduzidos dois experimentos com o objetivo de avaliar os efeitos de dois produtos comerciais sobre o desenvolvimento da cultura do arroz irrigado e sobre a incidência da mancha-de-grãos causada por Helminthosporium oryzae. Um dos produtos consistia de rizobactérias promotoras de crescimento de plantas (RPCPs e micorrizas (Biosol e o outro era constituído por micronutrientes e amino

  17. Utilization of wastewater on seed germination and physioogical parameters of rice (Oryza sativa L.)

    Science.gov (United States)

    Huy, V.; Iwai, C. B.

    2018-03-01

    Due to increasing world population and demand, fresh water availability is becoming a limited resource. Reusing wastewater for agriculture has received attention since it contains nutrients, which are beneficial for growing crops. Even though wastewater can be used as the nutrient source for the plant, the toxicity of wastewater can still be a cause for concern and investigation. The main objective of this paper was to assess the effect of different sources of wastewater on the germination of Jasmine rice (KDML105), White rice (Phatum Thani 1), and Sticky rice (RD6) under laboratory conditions. Petri dish cultures were used with various concentrations (0, 50, and 100%) of wastewater collected from swine farm, aquaculture activity, and domestic. Seed germination, root length, shoot length, seed vigor index, fresh weight and dry weight were measured after each experiment. The results have shown that domestic wastewater and aquaculture activity wastewater did not decrease performance of Jasmine rice (KDML105), White rice (Phatum thani 1), and Sticky rice (RD6) while the germination of Jasmine rice (KDML105), White rice (Phatum thani 1), and Sticky rice (RD6) decreased when irrigated with swine farm wastewater. Therefore, using domestic and aquaculture activity wastewater for irrigation are suitable for growth of these crop.

  18. An assessment of colostomy irrigation.

    Science.gov (United States)

    Laucks, S S; Mazier, W P; Milsom, J W; Buffin, S E; Anderson, J M; Warwick, M K; Surrell, J A

    1988-04-01

    One hundred patients with permanent sigmoid colostomies were surveyed to determine their satisfaction and success with the "irrigation" technique of colostomy management. Most patients who irrigate their colostomies achieve continence. Odors and skin irritation are minimized. The irrigation method is economical, time efficient, and allows a reasonably liberal diet. It avoids bulky appliances and is safe. In appropriately selected patients, the irrigation technique is the method of choice for management of an end-sigmoid colostomy.

  19. Imaging analysis of direct alanine uptake by rice seedlings

    International Nuclear Information System (INIS)

    Nihei, Naoto; Masuda, Sayaka; Rai, Hiroki; Nakanishi, Tomoko M.

    2008-01-01

    We presented alanine, a kind of amino acids, uptake by a rice seedling to study the basic mechanism of the organic fertilizer effectiveness in organic farming. The rice grown in the culture solution containing alanine as a nitrogen source absorbed alanine approximately two times faster than that grown with NH 4 + from analysis of 14 C-alanine images by Imaging Plate method. It was suggested that the active transport ability of the rice seeding was induced in roots by existence of alanine in the rhizosphere. The alanine uptake images of the rice roots were acquired every 5 minutes successively by the real-time autoradiography system we developed. The analysis of the successive images showed that alanine uptake was not uniform throughout the root but especially active at the root tip. (author)

  20. Phenotypic Responses of Twenty Diverse Proso Millet (Panicum miliaceum L. Accessions to Irrigation

    Directory of Open Access Journals (Sweden)

    Cedric Habiyaremye

    2017-03-01

    Full Text Available To date, little research has been conducted on the phenotypic responses of proso millet to drought and deficit irrigation treatments in the dryland wheat-based cropping systems of the Palouse bioregion of the U.S. The objectives of this study were to evaluate critical agronomic traits of proso millet, including emergence, plant height, days to heading, days to maturity, and grain yield, with and without supplemental irrigation. Twenty diverse proso millet accessions, originating from Bulgaria, Czechoslovakia, Morocco, the former Soviet Union, Turkey, and the United States, were grown in irrigated and non-irrigated treatments under organic conditions in Pullman, WA, from 2012 to 2014. Irrigation was shown to significantly improve emergence and increase plant height at stem extension and to hasten ripening of all the varieties, whereas heading date was not affected by irrigation in two of the three years tested. Irrigation resulted in higher mean seed yield across all varieties, with ‘GR 665’ and ‘Earlybird’ performing best under irrigation. Seed yield was highest in ‘GR 658’ and ‘Minsum’ in the non-irrigated treatment, suggesting the importance of identification and utilization of varieties adapted to low rainfall conditions. The highest yielding varieties in irrigated systems are unlikely be the highest yielding in dryland systems. Our results suggest that millet has potential as a regionally novel crop for inclusion in traditional dryland cropping rotations in the Palouse ecosystem, thereby contributing to increased cropping system diversity.

  1. Induction of drought tolerant mutants of rice

    International Nuclear Information System (INIS)

    El-Hissewy, A.A.; Abd Allah, A.

    2001-01-01

    The ultimate goal of crop breeding is to develop varieties with a high yield potential and desirable agronomic characteristics. In Egypt, the most important qualities sought by breeders have been high yield potential, resistance to major diseases and insects, and improved grain and eating quality. However, breeding efforts should concentrate on varieties with the potential to minimize yield losses under unfavorable conditions such as drought, and to maximize yields when conditions are favorable. Rice (Oryza sativa L.) in Egypt is completely irrigated and a significant portion of the rice cultivated area is subject to water deficit resulting from an inadequate or insufficient irrigation supply. Drought tolerance is a complex trait in that it results from the interaction of histological and physiological characters of plant with environmental factors, both above-ground and under-ground. Accordingly, root characters are closely related to drought tolerance. Little attention has been paid in Egyptian breeding programs to root characters and their relation to shoot characters. Furthermore, induced mutations are considered as one of the most important methods to induce useful mutants, especially with improved root characters, to overcome the drought problem. The present investigation aimed to study the effect of different doses of gamma rays on several characters of three Egyptian rice varieties, i.e. 'Giza 171', 'Giza 175' and 'Giza 176' and to induce one or more mutants possessing drought tolerance

  2. Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

    International Nuclear Information System (INIS)

    Al-Ghobari, H.M.; Mohammad, F.S.; El Marazky, M.S.A.

    2016-01-01

    Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema) in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

  3. Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ghobari, H.M.; Mohammad, F.S.; El Marazky, M.S.A.

    2016-07-01

    Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema) in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

  4. Water footprint of cotton, wheat and rice production in Central Asia

    NARCIS (Netherlands)

    Martinez-Aldaya, Maite; Munoz, G.; Hoekstra, Arjen Ysbert

    2010-01-01

    The hydrology of the Aral Sea Basin during the past few decades has been largely determined by the decision to develop irrigated agriculture on a large scale to produce cotton for export in the 1960s. The irrigated area has grown to 8 million hectares, using practically the entire available flow of

  5. Elemental content of Vietnamese rice. Part 2. Multivariate data analysis.

    Science.gov (United States)

    Kokot, S; Phuong, T D

    1999-04-01

    Rice samples were obtained from the Red River region and some other parts of Vietnam as well as from Yanco, Australia. These samples were analysed for 14 elements (P, K, Mg, Ca, Mn, Zn, Fe, Cu, Al, Na, Ni, As, Mo and Cd) by ICP-AES, ICP-MS and FAAS as described in Part 1. This data matrix was then submitted to multivariate data analysis by principal component analysis to investigate the influences of environmental and crop cultivation variables on the elemental content of rice. Results revealed that geographical location, grain variety, seasons and soil conditions are the most likely significant factors causing changes in the elemental content between the rice samples. To assess rice quality according to its elemental content and physio-biological properties, a multicriteria decision making method (PROMETHEE) was applied. With the Vietnamese rice, the sticky rice appeared to contain somewhat higher levels of nutritionally significant elements such as P, K and Mg than the non-sticky rice. Also, rice samples grown during the wet season have better levels of nutritionally significant mineral elements than those of the dry season, but in general, the wet season seemed to provide better overall elemental and physio-biological rice quality.

  6. A digital photography and analysis system for estimation of root and shoot development in rice weed suppression studies in the field

    Science.gov (United States)

    Rice germplasm with an inherent ability to suppress weeds can potentially improve the economics and sustainability of weed control in rice. We devised a simple, rapid, and inexpensive digital imaging system to quantify several shoot and root growth characteristics in field-grown rice plants that ha...

  7. Solophos fertilizer improved rice plant growth in aerobic soil

    OpenAIRE

    NIE, Lixiao; PENG, Shaobing; BOUMAN, Bas A.M.; HUANG, Jianliang; CUI, Kehui; VISPERAS, Romeo M.; PARK, Hong-Kyu

    2007-01-01

    Yield decline of continuous monocropping of aerobic rice is the major constraint to the wide adoption of aerobic rice technology. This study was conducted to determine if solophos fertilizer could be used to reverse the yield decline of this cropping system using pot and micro-plot experiments. The soil for the pot experiment was collected from a field where aerobic rice has been grown continuously for 11 seasons at the IRRI farm. Four rates (4, 6, 8, and 10gpot^) of solophos application were...

  8. Methods to estimate irrigated reference crop evapotranspiration - a review.

    Science.gov (United States)

    Kumar, R; Jat, M K; Shankar, V

    2012-01-01

    Efficient water management of crops requires accurate irrigation scheduling which, in turn, requires the accurate measurement of crop water requirement. Irrigation is applied to replenish depleted moisture for optimum plant growth. Reference evapotranspiration plays an important role for the determination of water requirements for crops and irrigation scheduling. Various models/approaches varying from empirical to physically base distributed are available for the estimation of reference evapotranspiration. Mathematical models are useful tools to estimate the evapotranspiration and water requirement of crops, which is essential information required to design or choose best water management practices. In this paper the most commonly used models/approaches, which are suitable for the estimation of daily water requirement for agricultural crops grown in different agro-climatic regions, are reviewed. Further, an effort has been made to compare the accuracy of various widely used methods under different climatic conditions.

  9. Nitrate leaching beneath a containerized nursery crop receiving trickle or overhead irrigation.

    Science.gov (United States)

    Colangelo, D J; Brand, M H

    2001-01-01

    Container production of nursery crops is intensive and a potential source of nitrogen release to the environment. This study was conducted to determine if trickle irrigation could be used by container nursery producers as an alternative to standard overhead irrigation to reduce nitrogen release into the environment. The effect of overhead irrigation and trickle irrigation on leachate nitrate N concentration, flow-weighted nitrate N concentration, leachate volume, and plant growth was investigated using containerized rhododendron (Rhododendron catawbiense Michx. 'Album') supplied with a controlled-release fertilizer and grown outdoors on top of soil-monolith lysimeters. Leachate was collected over two growing seasons and overwinter periods, and natural precipitation was allowed as a component of the system. Precipitation accounted for 69% of the water entering the overhead-irrigated system and 80% of the water entering the trickle-irrigated system. Leachate from fertilized plants exceeded the USEPA limit of 10 mg L(-1) at several times and reached a maximum of 26 mg L(-1) with trickle irrigation. Average annual loss of nitrate N in leachate for fertilized treatments was 51.8 and 60.5 kg ha(-1) for the overhead and trickle treatments, respectively. Average annual flow-weighted concentration of nitrate N in leachate of fertilized plants was 7.2 mg L(-1) for overhead irrigation and 12.7 mg L(-1) for trickle irrigation. Trickle irrigation did not reduce the amount of nitrate N leached from nursery containers when compared with overhead irrigation because precipitation nullified the potential benefits of reduced leaching fractions and irrigation inputs provided under trickle irrigation.

  10. Optimized Subsurface Irrigation System: The Future of Sugarcane Irrigation

    Directory of Open Access Journals (Sweden)

    M. H. J. P. Gunarathna

    2018-03-01

    Full Text Available Climate change may harm the growth and yield of sugarcane (Saccharum officinarum L. without the introduction of appropriate irrigation facilities. Therefore, new irrigation methods should be developed to maximize water use efficiency and reduce operational costs. OPSIS (optimized subsurface irrigation system is a new solar-powered automatic subsurface irrigation system that creates a phreatic zone below crop roots and relies on capillarity to supply water to the root zone. It is designed for upland crops such as sugarcane. We investigated the performance of OPSIS for irrigating sugarcane and evaluated its performance against sprinkler irrigation under subtropical conditions. We conducted field experiments in Okinawa, Japan, over the period from 2013 to 2016 and took measurements during spring- and summer-planted main crops and two ratoon crops of the spring-planted crop. Compared with sprinkler irrigation, OPSIS produced a significantly higher fresh cane yield, consumed less irrigation water and provided a higher irrigation water use efficiency. We conclude that OPSIS could be adopted as a sustainable solution to sugarcane irrigation in Okinawa and similar environments.

  11. Utilization of rice straw and different treatments to improve its feed value for ruminants: A review

    NARCIS (Netherlands)

    Sarnklong, C.; Cone, J.W.; Pellikaan, W.F.; Hendriks, W.H.

    2010-01-01

    This paper gives an overview of the availability, nutritive quality, and possible strategies to improve the utilization of rice straw as a feed ingredient for ruminants. Approximately 80% of the rice in the world is grown by small-scale farmers in developing countries, including South East Asia. The

  12. Stimulate The Growth of Rice Using Endophytic Bacteria from Lowland Rice Plant Tissue

    Directory of Open Access Journals (Sweden)

    Nuni Gofar

    2015-07-01

    Full Text Available Exploration and selection of endophytic bacteria from healthy food crops grown in lowland ecosystem is important to be conducted in order to get growth-stimulating endophytic bacteria at soil with low fertility level so that capable to optimize initial growth of food crops and subsequently can increase productivity level of lowland soil.The research objective was to isolate and to test the IAA-producing endophytic bacteria isolate in stimulating the rice crop growth at lowland area. Endophytic bacteria are isolated from tissues of rice, corn and peanut crops which grown at shallow swamp land in Ogan Ilir and Ogan Komering Ilir Districts, South Sumatra, Indonesia. There was nine isolates of nitrogen-fixer endophytic bacteria that capable to contribute IAA phytohormone into their growth media. The P31 isolate from rice crop tisssue of 2 months old produce the best rice sprouts than other isolates. This isolate can contribute of about 10 mg kg-1 IAA to its growth medium and increase the crowns dry weight and the roots dry weight respectively with magnitudes of 133% and 225% compared to control treatment. Concentration and absorbtion of N for rice crops innoculated with P31 isolates had increased by 169% and 400%, recpectively. The P31 isolates had been identified as Burkholderia pseudomallei (also known as Pseudomonas pseudomallei.

  13. Weed Control with Cover Crops in Irrigated Potatoes

    OpenAIRE

    G.H. Mehring; J.E. Stenger; H.M. Hatterman-Valenti

    2016-01-01

    Field experiments at Oakes, ND, USA in 2010 and Carrington, ND, USA in 2011 were conducted to evaluate the potential for cover crops grown in the Northern Great Plains, USA in order to reduce weed emergence and density in irrigated potatoes. Treatments included five cover crop treatments and three cover crop termination treatments. Termination of cover crops was done with glyphosate, disk-till, and roto-till. Cover crop biomass accumulation was greatest for rye/canola and triticale at Oakes, ...

  14. Portable photovoltaic irrigation pumps

    Energy Technology Data Exchange (ETDEWEB)

    Furber, J. D.

    1980-07-01

    Experiences in developing a solar-powered irrigation pump to meet the needs of poor farmers in developing nations are summarized. The design which evolved is small and portable, employing a high-efficiency electric pump, powered by photovoltaic panels. Particular emphasis is placed on how the system works, and on early field problems experienced with the first prototypes. The resolution of these problems and the performance of actual systems in various countries is presented and user responses are noted.

  15. Mathematical model for scheduling irrigation for swamp rice in Port ...

    African Journals Online (AJOL)

    While the mother model indicated that the planted crops will be under severe water stress because the values of their d2 were below the allowable range of water depletion except in weeks 1,7,10,16 and 17 with their d2 values to be; 178.50mm, 181.47mm, 162.11mm, 198.80mm and 187.60mm respectively. Water ...

  16. The impact of irrigated rice on the transmission of schistosomiasis ...

    African Journals Online (AJOL)

    The prevalence and intensity of the infection caused by schistosomiasis and geohelmintiasis were ... high before implementation (Audibert et al., 2001;. Barboza et al., 2012). .... body weight) and with Mebendazole for .... CI = Confidence interval;LRT = lke lihood ratio Test; .... composition of the soil and climatic factors.

  17. Irrigation Suitability Assessment of Effluents From West Kano Rice ...

    African Journals Online (AJOL)

    Choice-Academy

    lake water, and an excess in effluents. The excess nitrates in effluents pollute the lake, but could help as crop .... modelling assessment method proposed in this study can be used to ... economic and environmental impact assessment research ...

  18. Impact of long-term wastewater irrigation on sorption and transport of atrazine in Mexican agricultural soils

    OpenAIRE

    Muller, K.; Duwig, Céline; Prado, B.; Siebe, C.; Hidalgo, C.; Etchevers, J.

    2012-01-01

    In the Mezquital Valley, Mexico, crops have been irrigated with untreated municipal wastewater for more than a century. Atrazine has been applied to maize and alfalfa grown in the area for weed control for 15 years. Our objectives were to analyse (i) how wastewater irrigation affects the filtering of atrazine, and (ii) if the length of irrigation has a significant impact. We compared atrazine sorption to Phaeozems that have been irrigated with raw wastewater for 35 (P35) and 85 (P85) years wi...

  19. [Irrigation in colostomies].

    Science.gov (United States)

    Campo, Juana; Lecona, Ana; Caparrós, M Rosario; Barbero, M Antonia; Javier Cerdán, F

    2002-01-01

    The degree of acceptation of irrigation from a colostomy varies ostensibly from some cases to others, therefore, we study what occurs in our medium, separating those patients which have previously undergone other procedures (Group A) from those patients who have been informed and trained about the immediate postoperative period (Group B). 48 patients, 22 or 46% of these patients were considered not apt for irrigation. Of the 26 to whom this procedure was proposed, 14 or 54% accepted. Of these, 5 or 36% abandoned its use while 9 continued its use; this is 64% of those who accepted this procedure, 35% of those to whom it was proposed and 19% of the total study group. 189 patients. This procedure was not recommended to 95 patients, 50%. Of the 94 patients to whom this procedure was proposed, 65 or 69% accepted. Of these, 22 or 34% abandoned its use while 43 continued its use; this is 66% of those; who accepted this procedure, 46% of those to whom it was proposed and 23% of the total study group. In our medium, the practice of irrigation oscillates between 19 and 23% of patients who have undergone a colostomy, without any significant difference referring to the moment when a patient started this procedure. A first report on this study was submitted in the III National Congress for Nursing in Colostomies.

  20. Effect of Irrigation Methods, Nitrogen and Phosphorus Fertilizer Rates on Sugar Beet Yield and Quality

    International Nuclear Information System (INIS)

    Janat, M.; Abudlkareem, J.

    2007-01-01

    The experiment was conducted at a research station near Adlib. Two irrigation methods, sprinkler irrigation and drip fertigation, two phosphorus rates and four nitrogen rates 0, 70, 140 and 210 kg N/ha were tested. All N fertilizers were injected for drip irrigation or broadcasted for the sprinkler-irrigated treatments in six equally split applications. Neutron probe Results revealed that the introduction of drip fertigation was not proved to be a water saving relative to sprinkler irrigation. Dry matter production was slightly increased for the drip-fertigated treatments relative to sprinkler irrigated treatments. Nitrogen use efficiency was not improved under drip fertigation relative to that of sprinkler irrigation. Application of phosphorus fertilizer improved sugar beet yield as well as N uptake. No significant differences in sugar beet yield were observed due to the application of N fertilizer under drip fertigation. On the other hand, there was a trend toward increasing sugar beet yield grown under sprinkler irrigation. Drip fertigation had no negative effects on sugar content and other related properties, furthermore some of those properties were enhanced due to the employment of drip fertigation. Field water-use efficiency followed a similar trend and was increased under sprinkler irrigation relative to drip-fertigation for sugar beet yield parameter.

  1. Effects of different irrigation methods on pepper yield and soilborne diseases incidence

    Directory of Open Access Journals (Sweden)

    Seral YÜCEL

    2013-12-01

    Full Text Available In this study, the effect of different irrigation strategies and irrigation methods on yields and the incidence of wilt (Fusarium oxysporum and root rot (Fusarium solani and Macrophomina phaseolina diseases causing significant yield losses on field grown processing red pepper is determined. Experiments were carried out at Topçu Station of the Soil and Water Resources Research Institute of Tarsus in 2010 and 2011. Karaisalı processing pepper (Capsicum annuum L. was used in the experiments. Three furrows and five drip irrigation treatments were used in the study. The disease incidence rates were found 8.0-18.2% in furrow irrigation plots and 4.5-10.0% in drip irrigation plots in 2010, while it was 3.4-9.7% in furrow irrigation plots and 2.2-4.5% in drip irrigation plots in 2011. Pepper yields ranged from 3 416 to 4 417 kg da-1 and 3 376 to 4 779 kg da-1 in drip irrigated plots in 2010 and 2011, respectively. However, yields varied between 3 172-3 559 kg da-1 and 2 932-4 150 kg da-1 in furrow irrigated plots in 2010 and 2011 growing seasons.

  2. Impacts of climate change on rice production in Africa and causes of simulated yield changes.

    Science.gov (United States)

    van Oort, Pepijn A J; Zwart, Sander J

    2018-03-01

    This study is the first of its kind to quantify possible effects of climate change on rice production in Africa. We simulated impacts on rice in irrigated systems (dry season and wet season) and rainfed systems (upland and lowland). We simulated the use of rice varieties with a higher temperature sum as adaptation option. We simulated rice yields for 4 RCP climate change scenarios and identified causes of yield declines. Without adaptation, shortening of the growing period due to higher temperatures had a negative impact on yields (-24% in RCP 8.5 in 2070 compared with the baseline year 2000). With varieties that have a high temperature sum, the length of the growing period would remain the same as under the baseline conditions. With this adaptation option rainfed rice yields would increase slightly (+8%) but they remain subject to water availability constraints. Irrigated rice yields in East Africa would increase (+25%) due to more favourable temperatures and due to CO2 fertilization. Wet season irrigated rice yields in West Africa were projected to change by -21% or +7% (without/with adaptation). Without adaptation irrigated rice yields in West Africa in the dry season would decrease by -45% with adaptation they would decrease significantly less (-15%). The main cause of this decline was reduced photosynthesis at extremely high temperatures. Simulated heat sterility hardly increased and was not found a major cause for yield decline. The implications for these findings are as follows. For East Africa to benefit from climate change, improved water and nutrient management will be needed to benefit fully from the more favourable temperatures and increased CO2 concentrations. For West Africa, more research is needed on photosynthesis processes at extreme temperatures and on adaptation options such as shifting sowing dates. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  3. Selectivity of pesticides used in rice crop on Telenomus podisi and Trichogramma pretiosum

    OpenAIRE

    Pazini,Juliano de Bastos; Grützmacher,Anderson Dionei; Martins,José Francisco da Silva; Pasini,Rafael Antônio; Rakes,Matheus

    2016-01-01

    ABSTRACT Telenomus and Trichogramma species stand out as agents for the biological control in rice crops, and the main strategy for preserving them is the use of selective pesticides. This study aimed at evaluating the toxicity of pesticides used in irrigated rice crop on Telenomus podisi Ashmead (Hymenoptera: Platygastridae) and Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). Adults of these parasitoids were exposed to dry residues of pesticides, in a completely randomized exp...

  4. ROOT CANAL IRRIGANTS AND IRRIGATION TECHNIQUES: A REVIEW

    OpenAIRE

    Aniketh; Mohamed; Geeta; Nandakishore; Gourav Kumar; Patrick Timothy; Jayson Mathew; Sahle Abdul

    2015-01-01

    Root canal irrigation is not much emphasised in endodontic therapy. Most articles discussed are on root canal shaping and obturation not much emphasis is given for irrigation. There are many irrigation solutions which are introduced into market. The primary objective of root canal therapy is the ret ention of the pulpless or pulpally involved tooth with its associated periapical tissues in a healthy state. Achievement of this objective requires that the pulpal spaces and con...

  5. Drought resistant rice mutants, characteristics and discussions on possibilities for planting them in some Arab Countries which import rice

    International Nuclear Information System (INIS)

    Abo-Hegazi, A.M.T.

    1994-01-01

    A number of drought resistant mutants of rice were produced from ordinary rice varieties being planted in several parts of Egypt through utilization of gamma rays as a mutagen. The mutants have water requirements less than one half of that of their mother varieties. According to official data, authorities in Egypt insure about 18000 M 3 of irrigation water for every hectare (10000 M 2 ) of rice and about 6700 M 3 , 6900 M 3 for every hectare of corn and ground nuts, respectively. Peanuts and corn are summer crops like the drought resistant rice mutants. The mentioned mutants can produce good yield under water requirements very near to that of corn and peanuts. The wide gap in agricultural food stuffs for the Arab Countries (more than 20000 million US $ annually) includes rice imports usually exceeds 700 million US $ per year> Rice imports of Arab Countries such as Saudi Arabia, Yemen, Syria, Libya and the Sudan, reached 180, 47, 21, 16 and 14 million US $ in 1988 as an example. Such countries could make use of the drought resistant rice mutants for plantation on water requirements very near to those of usual summer crops such as corn and peanuts which is significantly less than one half of water requirements of their mother varieties. Some characteristics of such mutants as well as discussions on possibilities for planting them in some of the nominated Arab Countries are presented. However, arrangements for ensuring the minimum water requirements during the growing period irrespective to rain which in many cases did not accord the growing period of the mutants should be taken if such countries wants to make use of the drought resistant rice mutants. The author believe that most if not all requirements of rice of such countries could locally be ensured through planting of the above mentioned rice mutants. In this case, maximizing the efficiency of utilizing the limited water resources of such countries could also be counted as another cause for presenting this

  6. Greenhouse irrigation control system design based on ZigBee and fuzzy PID technology

    Science.gov (United States)

    Zhou, Bing; Yang, Qiliang; Liu, Kenan; Li, Peiqing; Zhang, Jing; Wang, Qijian

    In order to achieve the water demand information accurately detect of the greenhouse crop and its precision irrigation automatic control, this article has designed a set of the irrigated control system based on ZigBee and fuzzy PID technology, which composed by the soil water potential sensor, CC2530F256 wireless microprocessor, IAR Embedded Workbench software development platform. And the time of Irrigation as the output .while the amount of soil water potential and crop growth cycle as the input. The article depended on Greenhouse-grown Jatropha to verify the object, the results show that the system can irrigate timely and appropriately according to the soil water potential and water demend of the different stages of Jatropha growth , which basically meet the design requirements. Therefore, the system has broad application prospects in the amount of greenhouse crop of fine control irrigation.

  7. Estimation of rice yield affected by drought and relation between rice yield and TVDI

    Science.gov (United States)

    Hongo, C.; Tamura, E.; Sigit, G.

    2016-12-01

    Impact of climate change is not only seen on food production but also on food security and sustainable development of society. Adaptation to climate change is a pressing issue throughout the world to reduce the risks along with the plans and strategies for food security and sustainable development. As a key adaptation to the climate change, agricultural insurance is expected to play an important role in stabilizing agricultural production through compensating the losses caused by the climate change. As the adaptation, the Government of Indonesia has launched agricultural insurance program for damage of rice by drought, flood and pest and disease. The Government started a pilot project in 2013 and this year the pilot project has been extended to 22 provinces. Having the above as background, we conducted research on development of new damage assessment method for rice using remote sensing data which could be used for evaluation of damage ratio caused by drought in West Java, Indonesia. For assessment of the damage ratio, estimation of rice yield is a key. As the result of our study, rice yield affected by drought in dry season could be estimated at level of 1 % significance using SPOT 7 data taken in 2015, and the validation result was 0.8t/ha. Then, the decrease ratio in rice yield about each individual paddy field was calculated using data of the estimated result and the average yield of the past 10 years. In addition, TVDI (Temperature Vegetation Dryness Index) which was calculated from Landsat8 data in heading season indicated the dryness in low yield area. The result suggests that rice yield was affected by irrigation water shortage around heading season as a result of the decreased precipitation by El Nino. Through our study, it becomes clear that the utilization of remote sensing data can be promising for assessment of the damage ratio of rice production precisely, quickly and quantitatively, and also it can be incorporated into the insurance procedures.

  8. Rainfall Variability, Adaptation through Irrigation, and Sustainable Management of Water Resources in India

    Science.gov (United States)

    Fishman, R.

    2013-12-01

    Most studies of the impact of climate change on agriculture account for shifts in temperature and total seasonal (or monthly) precipitation. However, climate change is also projected to increase intra-seasonal precipitation variability in many parts of the world. To provide first estimates of the potential impact, I paired daily rainfall and rice yield data during the period 1970-2004, from across India, where about a fifth of the world's rice is produced, and yields have always been highly dependent on the erratic monsoon rainfall. Multivariate regression models revealed that the number of rainless days during the wet season has a statistically robust negative impact on rice yields that exceeds that of total seasonal rainfall. Moreover, a simulation of climate change impacts found that the negative impact of the projected increase in the number of rainless days will trump the positive impact of the projected increase in total precipitation, and reverse the net precipitation effect on rice production from positive (+3%) to negative (-10%). The results also indicate that higher irrigation coverage is correlated with reduced sensitivity to rainfall variability, suggesting the expansion of irrigation can effectively adapt agriculture to these climate change impacts. However, taking into account limitations on water resource availability in India, I calculate that under current irrigation practices, sustainable use of water can mitigate less than a tenth of the impact.

  9. Making the user visible: analysing irrigation practices and farmers’ logic to explain actual drip irrigation performance

    NARCIS (Netherlands)

    Benouniche, M.; Kuper, M.; Hammani, A.; Boesveld, H.

    2014-01-01

    The actual performance of drip irrigation (irrigation efficiency, distribution uniformity) in the field is often quite different from that obtained in experimental stations. We developed an approach to explain the actual irrigation performance of drip irrigation systems by linking measured

  10. Irrigation water management: Basic principles and applications

    OpenAIRE

    Ella, Victor B.

    2007-01-01

    This presentation defines the term, irrigation, as well as explains the common methods of irrigation in attempt to define the fundamental principles needed to wisely design an irrigation system. It outlines a typical drip irrigation set-up, and discusses management of an irrigation system, including water volume application suggestions. LTRA-5 (Agroforestry and Sustainable Vegetable Production)

  11. Studies on mosquitoes (Diptera: Culicidae and anthropicenvironment: 5- Breeding of Anopheles albitarsis in flooded rice fields in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1994-10-01

    Full Text Available Studies on breeding Anopheles albitarsis and association with rice growth in irrigated paddy fields were carried out during the rice cultivation cycle from December 1993 to March 1994. This period corresponded to the length of time of permanent paddy flooding. Breeding occurred in the early stage up until five weeks after transplantation when rice plant height was small. That inverse correlation may give potential direction to control measures.

  12. Agriculture Irrigation and Water Use

    OpenAIRE

    Bajwa, Rajinder S.; Crosswhite, William M.; Hostetler, John E.; Wright, Olivia W.; United States Department of Agriculture, Economic Research Service

    1992-01-01

    The 17 Western States, plus Arkansas, Florida, and Louisiana, account for 91 percent of all U.S. irrigated acreage, with the Western States alone contributing over 85 percent. This report integrates data on the distribution, characteristics, uses, and management of water resources from a wide variety of data sources. The report includes charts and tables on water use in irrigation; farm data comparing selected characteristics of irrigated and nonirrigated farms; and data on water applicatio...

  13. The Impact of Herbicide-Resistant Rice Technology on Phenotypic Diversity and Population Structure of United States Weedy Rice1[W][OPEN

    Science.gov (United States)

    Burgos, Nilda Roma; Singh, Vijay; Tseng, Te Ming; Black, Howard; Young, Nelson D.; Huang, Zhongyun; Hyma, Katie E.; Gealy, David R.; Caicedo, Ana L.

    2014-01-01

    The use of herbicide-resistant (HR) Clearfield rice (Oryza sativa) to control weedy rice has increased in the past 12 years to constitute about 60% of rice acreage in Arkansas, where most U.S. rice is grown. To assess the impact of HR cultivated rice on the herbicide resistance and population structure of weedy rice, weedy samples were collected from commercial fields with a history of Clearfield rice. Panicles from each weedy type were harvested and tested for resistance to imazethapyr. The majority of plants sampled had at least 20% resistant offspring. These resistant weeds were 97 to 199 cm tall and initiated flowering from 78 to 128 d, generally later than recorded for accessions collected prior to the widespread use of Clearfield rice (i.e. historical accessions). Whereas the majority (70%) of historical accessions had straw-colored hulls, only 30% of contemporary HR weedy rice had straw-colored hulls. Analysis of genotyping-by-sequencing data showed that HR weeds were not genetically structured according to hull color, whereas historical weedy rice was separated into straw-hull and black-hull populations. A significant portion of the local rice crop genome was introgressed into HR weedy rice, which was rare in historical weedy accessions. Admixture analyses showed that HR weeds tend to possess crop haplotypes in the portion of chromosome 2 containing the ACETOLACTATE SYNTHASE gene, which confers herbicide resistance to Clearfield rice. Thus, U.S. HR weedy rice is a distinct population relative to historical weedy rice and shows modifications in morphology and phenology that are relevant to weed management. PMID:25122473

  14. Current Insights into Research on Rice stripe virus

    Directory of Open Access Journals (Sweden)

    Won Kyong Cho

    2013-09-01

    Full Text Available Rice stripe virus (RSV is one of the most destructive viruses of rice, and greatly reduces rice production in China, Japan, and Korea, where mostly japonica cultivars of rice are grown. RSV is transmitted by the small brown plant-hopper (SBPH in a persistent and circulative-propagative manner. Several methods have been developed for detection of RSV, which is composed of four single-stranded RNAs that encode seven proteins. Genome sequence data and comparative phylogenetic analysis have been used to identify the origin and diversity of RSV isolates. Several rice varieties resistant to RSV have been selected and QTL analysis and fine mapping have been intensively performed to map RSV resistance loci or genes. RSV genes have been used to generate several genetically modified transgenic rice plants with RSV resistance. Recently, genome-wide transcriptome analyses and deep sequencing have been used to identify mRNAs and small RNAs involved in RSV infection; several rice host factors that interact with RSV proteins have also been identified. In this article, we review the current statues of RSV research and propose integrated approaches for the study of interactions among RSV, rice, and the SBPH.

  15. Linkage Mapping of Stem Saccharification Digestibility in Rice.

    Directory of Open Access Journals (Sweden)

    Bohan Liu

    Full Text Available Rice is the staple food of almost half of the world population, and in excess 90% of it is grown and consumed in Asia, but the disposal of rice straw poses a problem for farmers, who often burn it in the fields, causing health and environmental problems. However, with increased focus on the development of sustainable biofuel production, rice straw has been recognized as a potential feedstock for non-food derived biofuel production. Currently, the commercial realization of rice as a biofuel feedstock is constrained by the high cost of industrial saccharification processes needed to release sugar for fermentation. This study is focused on the alteration of lignin content, and cell wall chemotypes and structures, and their effects on the saccharification potential of rice lignocellulosic biomass. A recombinant inbred lines (RILs population derived from a cross between the lowland rice variety IR1552 and the upland rice variety Azucena with 271 molecular markers for quantitative trait SNP (QTS analyses was used. After association analysis of 271 markers for saccharification potential, 1 locus and 4 pairs of epistatic loci were found to contribute to the enzymatic digestibility phenotype, and an inverse relationship between reducing sugar and lignin content in these recombinant inbred lines was identified. As a result of QTS analyses, several cell-wall associated candidate genes are proposed that may be useful for marker-assisted breeding and may aid breeders to produce potential high saccharification rice varieties.

  16. Estrutura fitossociológia de um fragmento natural de floresta inundável em área de orizicultura irrigada, município de Lagoa da Confusão, Tocantins Phytosociologial structure of a natural fragment of floodplain forest in area of irrigated rice cultivation, municipal district of Lagoa da Confusão, Tocantins, Brazil

    Directory of Open Access Journals (Sweden)

    Elizabeth Rodrigues Brito

    2006-10-01

    , inserted in area of irrigated rice cultivation. For the phytosociological survey, all the tree/shrub individuals with perimeter at 1.30m (PBH > 15 cm were sampled. On the whole, 807 individuals, 35 families and 70 species were sampled. The species with higher VC, in descending order, were Hirtella racemosa Lam., Qualea multiflora Mart. and Cecropia pachystachya Trécul. The richest families in species were Fabaceae (9, Vochysiaceae (6, Annonaceae and Malvaceae (4. The Shannon diversity index (H' was 3.44. The distribution of diameter classes showed an inverted "J" curve, with most of the individuals being in the first class.

  17. Irrigation management of sigmoid colostomy.

    Science.gov (United States)

    Jao, S W; Beart, R W; Wendorf, L J; Ilstrup, D M

    1985-08-01

    Questionnaires were sent to 270 patients who had undergone abdominoperineal resection and sigmoid colostomy at the Mayo Clinic, Rochester, Minn, during the ten years from 1972 to 1982; 223 patients returned their questionnaires with evaluable data. Sixty percent of the patients were continent with irrigation, and 22% were incontinent with irrigation. Eighteen percent had discontinued irrigation for various reasons. The proportion continent was higher in women, younger patients, and previously constipated patients. A poorly constructed colostomy may cause acute angle, parastoma hernia, stomal prolapse, or stenosis and thus be the cause of failure of irrigation.

  18. Using artificial neural network and satellite data to predict rice yield in Bangladesh

    Science.gov (United States)

    Akhand, Kawsar; Nizamuddin, Mohammad; Roytman, Leonid; Kogan, Felix; Goldberg, Mitch

    2015-09-01

    Rice production in Bangladesh is a crucial part of the national economy and providing about 70 percent of an average citizen's total calorie intake. The demand for rice is constantly rising as the new populations are added in every year in Bangladesh. Due to the increase in population, the cultivation land decreases. In addition, Bangladesh is faced with production constraints such as drought, flooding, salinity, lack of irrigation facilities and lack of modern technology. To maintain self sufficiency in rice, Bangladesh will have to continue to expand rice production by increasing yield at a rate that is at least equal to the population growth until the demand of rice has stabilized. Accurate rice yield prediction is one of the most important challenges in managing supply and demand of rice as well as decision making processes. Artificial Neural Network (ANN) is used to construct a model to predict Aus rice yield in Bangladesh. Advanced Very High Resolution Radiometer (AVHRR)-based remote sensing satellite data vegetation health (VH) indices (Vegetation Condition Index (VCI) and Temperature Condition Index (TCI) are used as input variables and official statistics of Aus rice yield is used as target variable for ANN prediction model. The result obtained with ANN method is encouraging and the error of prediction is less than 10%. Therefore, prediction can play an important role in planning and storing of sufficient rice to face in any future uncertainty.

  19. Modeling water scarcity over south Asia: Incorporating crop growth and irrigation models into the Variable Infiltration Capacity (VIC) model

    Science.gov (United States)

    Troy, Tara J.; Ines, Amor V. M.; Lall, Upmanu; Robertson, Andrew W.

    2013-04-01

    Large-scale hydrologic models, such as the Variable Infiltration Capacity (VIC) model, are used for a variety of studies, from drought monitoring to projecting the potential impact of climate change on the hydrologic cycle decades in advance. The majority of these models simulates the natural hydrological cycle and neglects the effects of human activities such as irrigation, which can result in streamflow withdrawals and increased evapotranspiration. In some parts of the world, these activities do not significantly affect the hydrologic cycle, but this is not the case in south Asia where irrigated agriculture has a large water footprint. To address this gap, we incorporate a crop growth model and irrigation model into the VIC model in order to simulate the impacts of irrigated and rainfed agriculture on the hydrologic cycle over south Asia (Indus, Ganges, and Brahmaputra basin and peninsular India). The crop growth model responds to climate signals, including temperature and water stress, to simulate the growth of maize, wheat, rice, and millet. For the primarily rainfed maize crop, the crop growth model shows good correlation with observed All-India yields (0.7) with lower correlations for the irrigated wheat and rice crops (0.4). The difference in correlation is because irrigation provides a buffer against climate conditions, so that rainfed crop growth is more tied to climate than irrigated crop growth. The irrigation water demands induce hydrologic water stress in significant parts of the region, particularly in the Indus, with the streamflow unable to meet the irrigation demands. Although rainfall can vary significantly in south Asia, we find that water scarcity is largely chronic due to the irrigation demands rather than being intermittent due to climate variability.

  20. Assessment of Irrigation Water Quality and Suitability for Irrigation in ...

    African Journals Online (AJOL)

    A number of factors like geology, soil, effluents, sewage disposal and other environmental conditions in which the water stays or moves and interacts are among the factors that affect the quality of irrigation water. This study was conducted to determine the quality and suitability of different water sources for irrigation purpose ...

  1. Effect of irrigation on heavy metals content of wastewater irrigated ...

    African Journals Online (AJOL)

    There is an urgent need to educate farmers on the dangers of the presence of heavy metals in soils as well as the quality of irrigation water especially if it comes from tanning industries for increased crop production. Accordingly, soil and irrigation wastewater study was conducted to assess the concentrations of heavy ...

  2. The role of biotechnology to ensure rice food security

    International Nuclear Information System (INIS)

    Teng, P.S.

    2002-01-01

    Rice as a food is key to the survival of more than 60% of the world population, most of whom live in Asia. Food security in Asia is therefore strongly dependent on an adequate, available supply of affordable rice. Experts estimate that global rice supply would need to increase at an average of 1.7% per annum for the next 20 years, and average rice yields must roughly double in the next 20 years in both the irrigated and favourable rainfed lowland environments, if a global shortage is to be avoided. At the same time that the need to increase total production, and unit area productivity is being felt, society is also demanding that agricultural practices be environment friendly and be part of a sustainable agricultural system. Rice breeders have seen increased difficulties to source and utilize new genetic resources for genetic improvement of yield potential from within the rice genome. As with other cereals, rice yield potential has not been dramatically increased in the last decade when compared to the quantum increase of the early Green Revolution years. Furthermore, pest-induced losses currently account for up to 30% of the loss in yield potential. Biotechnology, especially recombinant DNA technology, offers tools to transfer genes from outside the rice genome to address the critical issues of raising the yield potential, increasing tolerance or resistance to insects, diseases and a biotic stresses, to increase the efficiency of pest management, and also to improve the nutritive value of the rice grain. Genetically modified crops have a demonstrated record of environmental and food safety, and all such crops undergo a process of safety assessment and regulatory approval before they are put into the marketplace. Serious social issues, however, arise in matching the capacity of biotechnology to change crops, and in what changes society is willing to accept; and at this early stage of biotechnology applications, science-based approaches are important so that emotion

  3. The effect of naturally acidified irrigation water on agricultural volcanic soils. The case of Asembagus, Java, Indonesia

    NARCIS (Netherlands)

    Los, A.M.D.; Vriend, S.P.; Bergen, M.J.; Gaans, R.F.M.

    2008-01-01

    Acid water from the Banyuputih river (pH similar to 3.5) is used for the irrigation of agricultural land in the Asembagus coastal area (East Java, Indonesia), with harmful consequences for rice yields. The river water has an unusual composition which is caused by seepage from the acidic Kawah Ijen

  4. Transferability Of DEMETER. A Case Study Of The Irrigation Scheme Of Veiga De Chaves

    Science.gov (United States)

    Baptista, A.; Sousa, V.

    2006-08-01

    DEMETER is a research and demonstration project, designed to assess and demonstrate how the integration of Earth Observation techniques in routine Irrigation Advisory Services can improve efficiency in the use of irrigation water. The objectives of this paper are: (1) to analyze the interest in the feasibility of transferring the DEMETER technology to the irrigation scheme of Chaves: (2) to identify the factors that, in general, favour the usefulness of this technology. The irrigation infrastructure and methods, the size and number of irrigation parcels and the main crops grown at the irrigation scheme of Chaves have been recorded. Also a socio-economic description has been done. Field visits, interviews with the staff of water association, and an inquiry to a sample of 107 farmers were made. The main results are: each farmer pays an area based annual fee, independent of the amount of water used for irrigation; most of the irrigated parcels are of very small size, 0.3 ha in average, mostly irrigated by surface methods; the most representative crops grown are potato, forage maize, and several different horticultural crops; an important part of the production is for self-consumption. The farmers are aging and the new generations prefer other jobs than agriculture. A considerable number of farmers have another job in the nearby cities. The small size of the irrigated parcels limits the use of earth observation technologies to expensive high space resolution images. For the time being, farmers do not feel the need for an irrigation advisory service, manly because there is plenty of water which is not bought proportionally to its use. However, circumstances are changing rapidly and, relatively new for the region, environmental concerns related with irrigation, manly nitrate leaching by excess watering of crops prompts the need for an irrigation advisory service in order to maintain crop production with a more rational use of water. The DEMETER technology could be a

  5. Organic rice IPM research update in the United States

    Science.gov (United States)

    U.S. organic rice production has steadily increased over the past decade, with a majority of the acreage being grown in the southern region. Because of the warm and humid environments and the long growing season in the region, weed, disease and insect pests are among the primary factors limiting org...

  6. Some aspects of photoperiodism in rice (Oryza sativa L.)

    NARCIS (Netherlands)

    Best, R.

    1961-01-01

    Photoperiodism was studied in 417 rice varieties of which 28, selected by differences in photoperiodic response, were studied in more detail. The plants were usually grown under 16 different photoperiods ranging from 5 to 24 h. In detailed experiments the types of response to short and long days

  7. How Patients Experience Antral Irrigation

    Directory of Open Access Journals (Sweden)

    Karin Blomgren

    2015-01-01

    Full Text Available Background Antral irrigation earlier had an important role in the diagnosis and treatment of rhinosinusitis. Nowadays, it is often considered too unpleasant. However, the experience of patients of this procedure has been very seldom evaluated. Nor has the effect on pain in rhinosinusitis been evaluated. The aim of this study was to evaluate patients’ experience of discomfort and pain during antral irrigation. We also assessed facial pain caused by rhinosinusitis before the procedure and pain soon after the procedure. Methods Doctors and 121 patients completed their questionnaires independently after antral irrigation in a university clinic, in a private hospital, and at a communal health center. Results Patients experienced mild pain during antral irrigation (mean and median visual analog scale score: <3. Their experience of pain during antral irrigation was closely comparable to pain during dental calculus scaling. Facial pain assessed before antral irrigation decreased quickly after the procedure. Conclusions Antral irrigation was well tolerated as an outpatient procedure. The procedure seems to relieve facial pain caused by the disease quickly. The role of antral irrigation in the treatment of acute rhinosinusitis will need further investigation.

  8. Irrigation management in organic greenhouse

    NARCIS (Netherlands)

    Voogt, W.; Balendonck, J.; Berkelmans, R.; Enthoven, N.

    2017-01-01

    Irrigation in protected cultivation is essential due to the absence of natural precipitation. High evapotranspiration, due to higher temperature and prolonged cropping period, requires ample an adequate supply of water. The water supply in a greenhouse is solely carried out by irrigation and thus

  9. Scintigraphic assessment of colostomy irrigation.

    Science.gov (United States)

    Christensen, P.; Olsen, N.; Krogh, K.; Laurberg, S.

    2002-09-01

    OBJECTIVE: This study aims to evaluate colonic transport following colostomy irrigation with a new scintigraphic technique. MATERIALS AND METHODS: To label the bowel contents 19 patients (11 uncomplicated colostomy irrigation, 8 complicated colostomy irrigation) took 111In-labelled polystyrene pellets one and two days before investigation. 99mTc-DTPA was mixed with the irrigation fluid to assess its extent within the bowel. Scintigraphy was performed before and after a standardized washout procedure. The colon was divided into three segments 1: the caecum andascending colon; 2: the transverse colon; 3: the descending and sigmoid colon. Assuming ordered evacuation of the colon, the contribution of each colonic segment to the total evacuation was expressed as a percentage of the original segmental counts. These were added to reach a total defaecation score (range: 0-300). RESULTS: In uncomplicated colostomy irrigation, the median defaecation score was 235 (range: 145-289) corresponding to complete evacuation of the descending and transverse colon and 35% evacuation of the caecum/ascending colon. In complicated colostomy irrigation it was possible to distinguish specific emptying patterns. The retained irrigation fluid reached the caecum in all but one patient. CONCLUSION: Scintigraphy can be used to evaluate colonic emptying following colostomy irrigation.

  10. Are There Infinite Irrigation Trees?

    Science.gov (United States)

    Bernot, M.; Caselles, V.; Morel, J. M.

    2006-08-01

    In many natural or artificial flow systems, a fluid flow network succeeds in irrigating every point of a volume from a source. Examples are the blood vessels, the bronchial tree and many irrigation and draining systems. Such systems have raised recently a lot of interest and some attempts have been made to formalize their description, as a finite tree of tubes, and their scaling laws [25], [26]. In contrast, several mathematical models [5], [22], [10], propose an idealization of these irrigation trees, where a countable set of tubes irrigates any point of a volume with positive Lebesgue measure. There is no geometric obstruction to this infinitesimal model and general existence and structure theorems have been proved. As we show, there may instead be an energetic obstruction. Under Poiseuille law R(s) = s -2 for the resistance of tubes with section s, the dissipated power of a volume irrigating tree cannot be finite. In other terms, infinite irrigation trees seem to be impossible from the fluid mechanics viewpoint. This also implies that the usual principle analysis performed for the biological models needs not to impose a minimal size for the tubes of an irrigating tree; the existence of the minimal size can be proven from the only two obvious conditions for such irrigation trees, namely the Kirchhoff and Poiseuille laws.

  11. Water-Yield Relations of Drip Irrigated Watermelon in Temperate Climatic Conditions

    Directory of Open Access Journals (Sweden)

    Pejić Borivoj

    2016-08-01

    Full Text Available The objective of the study, conducted in Vojvodina a northern part of the Serbia Republic, was to analyse the effect of drip irrigation on yield, evapotranspiration and water productivity of watermelon (Cirullus lanatus Thunb. grown with plasticulture. Irrigation was scheduled on the basis of water balance method. Daily evapotranspiration was computed using the reference evapotranspiration and crop coefficient. The yield of watermelon in irrigation conditions (37,28 t/ha was significantly higher compared to non irrigated (9,98 t/ha. Water used on evapotranspiration in irrigation conditions was 398 mm and 117 mm on non irrigated variant. The crop yield response factor of 1,04 for the whole growing season reveals that relative yield decrease was nearly equal to the rate of evapotranspiration deficit. The values of irrigation water use efficiency and evapotranspiration water use efficiency were 9,93 kg/m3 and 10,29 kg/m3 respectively. The determined results could be used as a good platform for watermelon growers in the region, in terms of improvement of the optimum utilization of irrigation water.

  12. Understanding the nature of methane emission from rice ecosystems as basis of mitigation strategies

    Energy Technology Data Exchange (ETDEWEB)

    Buendia, L.V.; Neue, H.U.; Wassmann, R. [International Rice Research Institute, Laguna (Philippines)] [and others

    1996-12-31

    Methane is considered as an important Greenhouse gas and rice fields are one of the major atmospheric methane sources. The paper aims to develop sampling strategies and formulate mitigation options based on diel (day and night) and seasonal pattern of methane emission. The study was conducted in 4 countries to measure methane flux using an automatic closed chamber system. A 24-hour bihourly methane emissions were continuously obtained during the whole growing season. Daily and seasonal pattern of methane fluxes from different rice ecosystems were evaluated. Diel pattern of methane emission from irrigated rice fields, in all sites, displayed similar pattern from planting to flowering. Fluxes at 0600, 1200, and 1800 h were important components of the total diel flux. A proposed sampling frequency to accurately estimate methane emission within the growing season was designed based on the magnitude of daily flux variation. Total methane emission from different ecosystems follow the order: deepwater rice > irrigated rice > rainfed rice. Application of pig manure increased total emission by 10 times of that without manure. Green manure application increased emission by 49% of that applied only with inorganic fertilizer. Removal of floodwater at 10 DAP and 35 DAP, within a period of 4 days, inhibited production and emission of methane. The level of variation in daily methane emission and seasonal emission pattern provides useful information for accurate determination of methane fluxes. Characterization of seasonal emission pattern as to ecologies, fertilizer amendments, and water management gives an idea of where to focus mitigation strategies for sustainable rice production.

  13. COMPETITIVENESS OF NIGERIAN RICE AND MAIZE PRODUCTION ECOLOGIES: A POLICY ANALYSIS APPROACH

    Directory of Open Access Journals (Sweden)

    Victor Olusegun Okoruwa

    2011-05-01

    Full Text Available The Nigerian rice and maize sectors are faced with decreasing supply and increasing demand as rice and maize have taken a strategic place of other staples leading to excessive importation and increasing government intervention. This study therefore assesses the competitiveness of Nigerian rice and maize production ecologies using the policy analysis matrix (PAM on a sample of 122 farmers. Results of the PAM revealed that outputs from the production ecologies are taxed. This is further confirmed by the Effective protection coefficient (EPC and Subsidy ratio to producers (SRP values, however, the production ecologies are subsidized on the use of tradable inputs. The production ecologies show a strong competitiveness at the farm level (under irrigated rice, upland rice and upland maize and a strong comparative advantage. Sensitivity analysis indicated that a 50 percent increase in output and a 13.3 percent depreciation of the domestic currency will increase competitiveness and comparative advantage of rice and maize production in all ecologies. The study recommends that government should ensure a level of policy stability in the rice and maize sectors, assist farmers with irrigated water scheme to ensure constant water supply, and increase the level of output through provision of improved seed varieties.

  14. Endophytic Colonization and In Planta Nitrogen Fixation by a Herbaspirillum sp. Isolated from Wild Rice Species

    Science.gov (United States)

    Elbeltagy, Adel; Nishioka, Kiyo; Sato, Tadashi; Suzuki, Hisa; Ye, Bin; Hamada, Toru; Isawa, Tsuyoshi; Mitsui, Hisayuki; Minamisawa, Kiwamu

    2001-01-01

    Nitrogen-fixing bacteria were isolated from the stems of wild and cultivated rice on a modified Rennie medium. Based on 16S ribosomal DNA (rDNA) sequences, the diazotrophic isolates were phylogenetically close to four genera: Herbaspirillum, Ideonella, Enterobacter, and Azospirillum. Phenotypic properties and signature sequences of 16S rDNA indicated that three isolates (B65, B501, and B512) belong to the Herbaspirillum genus. To examine whether Herbaspirillum sp. strain B501 isolated from wild rice, Oryza officinalis, endophytically colonizes rice plants, the gfp gene encoding green fluorescent protein (GFP) was introduced into the bacteria. Observations by fluorescence stereomicroscopy showed that the GFP-tagged bacteria colonized shoots and seeds of aseptically grown seedlings of the original wild rice after inoculation of the seeds. Conversely, for cultivated rice Oryza sativa, no GFP fluorescence was observed for shoots and only weak signals were observed for seeds. Observations by fluorescence and electron microscopy revealed that Herbaspirillum sp. strain B501 colonized mainly intercellular spaces in the leaves of wild rice. Colony counts of surface-sterilized rice seedlings inoculated with the GFP-tagged bacteria indicated significantly more bacterial populations inside the original wild rice than in cultivated rice varieties. Moreover, after bacterial inoculation, in planta nitrogen fixation in young seedlings of wild rice, O. officinalis, was detected by the acetylene reduction and 15N2 gas incorporation assays. Therefore, we conclude that Herbaspirillum sp. strain B501 is a diazotrophic endophyte compatible with wild rice, particularly O. officinalis. PMID:11679357

  15. Trace elements analysis of crops and vegetables grown around industrial areas of Faisalabad and Gujranwala cities using INAA and AAS

    International Nuclear Information System (INIS)

    Husaini, S.N.; Zaidi, J.H.; Matiullah; Akram, M.; Subhan, K.

    2010-01-01

    Industrial effluents pollution is a source of risk to the health of people living in industrial cities of Pakistan. Most of the untreated effluents are discharged to the nearby agricultural fields that pollutes the vegetation grown in such soil. A majority of the industries are not equipped with suitable recycling and effluent treatment plants. Consequently, toxic metals enter our food chain and results in significant health risks and serious diseases. In order to evaluate the concentration of toxic metals (namely As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb and Se), in crops and vegetable samples collected from the irrigated areas of Faisalabad and Gujranwala regions. Neutron activation analysis (NAA) and atomic absorption spectrometric (AAS) techniques have been used. All the observed metal concentrations were higher than the reported literature values. Moreover, the highest values of toxic metals of As (0.44 +- .03 mu g/g) and Co (0.5 +- 0.01 mu g/g), Mn (45.3 +- 2.0 mu g/g) and Sb (0.1 +- 0.01 mu g/g), Se (1.28 +- 0.06 mug/g) and Pb (3.84 +- 0.27 mu g/g) were found in tomato, bitter gourd and rice samples respectively. (author)

  16. Study on the 90Sr absorption by agricultural plants grown in soil from Daya Bay and Qinshan area

    International Nuclear Information System (INIS)

    Zhao Wenhu; Hou Lanxin; Xu Shiming

    1991-03-01

    The soil around the Qinshan and Daya Bay nuclear power plants were used in this study. The 90 Sr was spread into the soil by irrigation. The amount of 90 Sr spread were 0.037, 0.37, 3.7 and 370 Bq per gram soil respectively. After being treated, the soil were employed to grow rice, wheat, rape, bean, asparagus lettuce, tomato and peas. The harvested plants were divided into seeds, stems and leaves, husks and roots to measure their radioactivity separately. The results showed that the amount of 90 Sr absorbed by the plants was directly proportional to the 90 Sr content in the soil. The absorbed 90 Sr was mainly distributed in the stems and leaves. The seeds absorbed the least amount of 90 Sr compared with the other portions. The old leaves absorbed greater 90 Sr than the buds. The accumulated 90 Sr per unit dry weight of all plants grown in the soil from Daya Bay area was greater than in the soil from Qinshan area. More than 80% of total 90 Sr was distributed in the top layer from 0 to 4 cm. The concentration factors of various plants were also given

  17. Phytoremediation of arsenic contaminated paddy soils with Pteris vittata markedly reduces arsenic uptake by rice

    International Nuclear Information System (INIS)

    Ye Wenling; Khan, M. Asaduzzaman; McGrath, Steve P.; Zhao Fangjie

    2011-01-01

    Arsenic (As) accumulation in food crops such as rice is of major concern. To investigate whether phytoremediation can reduce As uptake by rice, the As hyperaccumulator Pteris vittata was grown in five contaminated paddy soils in a pot experiment. Over a 9-month period P. vittata removed 3.5-11.4% of the total soil As, and decreased phosphate-extractable As and soil pore water As by 11-38% and 18-77%, respectively. Rice grown following P. vittata had significantly lower As concentrations in straw and grain, being 17-82% and 22-58% of those in the control, respectively. Phytoremediation also resulted in significant changes in As speciation in rice grain by greatly decreasing the concentration of dimethylarsinic acid (DMA). In two soils the concentration of inorganic As in rice grain was decreased by 50-58%. The results demonstrate an effective stripping of bioavailable As from contaminated paddy soils thus reducing As uptake by rice. - Highlights: → Pteris vittata removed 3.5-11.4% of the total As from five contaminated paddy soils. → P. vittata decreased phosphate-extractable and soil solution As to a greater extent. → P. vittata reduced As concentration in rice grain by 18-83%. → P. vittata decreased methylated As in rice grain more than inorganic As. - Phytoremediation with P. vittata significantly reduced arsenic uptake by rice from contaminated paddy soils.

  18. Phytoremediation of arsenic contaminated paddy soils with Pteris vittata markedly reduces arsenic uptake by rice

    Energy Technology Data Exchange (ETDEWEB)

    Ye Wenling [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Khan, M. Asaduzzaman [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka-1207 (Bangladesh); McGrath, Steve P. [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Zhao Fangjie, E-mail: Fangjie.Zhao@bbsrc.ac.uk [Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom)

    2011-12-15

    Arsenic (As) accumulation in food crops such as rice is of major concern. To investigate whether phytoremediation can reduce As uptake by rice, the As hyperaccumulator Pteris vittata was grown in five contaminated paddy soils in a pot experiment. Over a 9-month period P. vittata removed 3.5-11.4% of the total soil As, and decreased phosphate-extractable As and soil pore water As by 11-38% and 18-77%, respectively. Rice grown following P. vittata had significantly lower As concentrations in straw and grain, being 17-82% and 22-58% of those in the control, respectively. Phytoremediation also resulted in significant changes in As speciation in rice grain by greatly decreasing the concentration of dimethylarsinic acid (DMA). In two soils the concentration of inorganic As in rice grain was decreased by 50-58%. The results demonstrate an effective stripping of bioavailable As from contaminated paddy soils thus reducing As uptake by rice. - Highlights: > Pteris vittata removed 3.5-11.4% of the total As from five contaminated paddy soils. > P. vittata decreased phosphate-extractable and soil solution As to a greater extent. > P. vittata reduced As concentration in rice grain by 18-83%. > P. vittata decreased methylated As in rice grain more than inorganic As. - Phytoremediation with P. vittata significantly reduced arsenic uptake by rice from contaminated paddy soils.

  19. Irrigating The Environment

    Science.gov (United States)

    Adamson, D.

    2017-12-01

    Water insecurity and water inequality are international issues that reduce economic growth. Countries are adopting alternative approaches to rebalance the share of water between all users to mitigate economic loss for this and future generations. However, recent reforms have struggled to provide the necessary arguments to obtain political protection of the process. In the absence of proof, rent-seeking arguments have challenged the benefit of restoring environmental flows by arguing that policy design fails to maximise the environmental benefits. This is a problem in Australia's Murray-Darling Basin (MDB), where despite establishing 3,200GL of environmental water, the policy is still under threat. Applied water economic policy advice fails, when it does not deal with uncertainty. The state-contingent analysis approach can map how individual decision makers can adapt to alternative states of water supply (i.e. drought, normal and wet) by reallocating inputs to obtain state-described outputs. By modelling changes to the states, or the frequency of the states occurring, climate change can modelled, and decision management responses explored. By treating the environment as another set of production systems, lessons learnt from managing perennial and annual agricultural production systems during the Millennium Drought in the MDB can be applied to explore the limits of irrigating the environment. The demand for water by a production system is a combination of state-general (must be irrigated every year e.g. perennial crop or permanent wetland) and state specific inputs (irrigate in response to the realise state). In simple terms, the greater the component of state-general water requirements a production system has, the less resilience it has when water supply is highly variable and if water is not available then production systems are irreversibly lost. While production systems that only need state-allocable water can adapt to alternative levels of scarcity without

  20. Choosing soil management systems for rice production on lowland soils in South Brazil

    NARCIS (Netherlands)

    Lima, A.C.R.; Hoogmoed, W.B.

    2009-01-01

    Lowland soils are commonly found in the state of Rio Grande do Sul, Southern of Brazil, where they represent around 20% of the total area of the state. Deficient drainage is the most important natural characteristic of these soils which therefore are mainly in use for flood-irrigated rice (Oriza

  1. Response of high yielding rice varieties to NaCl salinity in ...

    African Journals Online (AJOL)

    In order to find resistant varieties and study the reaction of some newly released high yielding varieties to different levels of salinity of irrigation water an experiment was conducted at the Rice Research Institute of Iran-Amol station in a greenhouse. Eight varieties, cultivated in pots, were tested with three levels of salinity (2, ...

  2. Understanding the physiological and molecular mechanisms of rice-microbial interactions that produce methane

    Science.gov (United States)

    The second most abundant greenhouse gas, methane, is ~25 times more potent in global warming potential than carbon dioxide, and 7-17% of atmospheric methane comes from flooded rice fields. Methane emissions can be greatly reduced by using alternate wetting and drying irrigation management and/or cul...

  3. An institutional perspective on farmers’ water management and rice production practices in Benin

    NARCIS (Netherlands)

    Totin, G.G.E.

    2013-01-01

    This thesis is part of the wider debate about the role of institutions in agricultural innovation processes. It

    investigates how institutions shape rice production in inland valleys in Benin. It starts from a scoping study

    (prior to this research) on smallholder irrigation in

  4. Microbial risk in wastewater irrigated lettuce: comparing Escherichia coli contamination from an experimental site with a laboratory approach.

    Science.gov (United States)

    Makkaew, P; Miller, M; Fallowfield, H J; Cromar, N J

    This study assessed the contamination of Escherichia coli, in lettuce grown with treated domestic wastewater in four different irrigation configurations: open spray, spray under plastic sheet cover, open drip and drip under plastic sheet cover. Samples of lettuce from each irrigation configuration and irrigating wastewater were collected during the growing season. No E. coli was detected in lettuce from drip irrigated beds. All lettuce samples from spray beds were positive for E. coli, however, no statistical difference (p > 0.05) was detected between lettuces grown in open spray or covered spray beds. The results from the field experiment were also compared to a laboratory experiment which used submersion of lettuce in wastewater of known E. coli concentration as a surrogate method to assess contamination following irrigation. The microbial quality of spray bed lettuces was not significantly different from submersed lettuce when irrigated with wastewater containing 1,299.7 E. coli MPN/100 mL (p > 0.05). This study is significant since it is the first to validate that the microbial contamination of lettuce irrigated with wastewater in the field is comparable with a laboratory technique frequently applied in the quantitative microbial risk assessment of the consumption of wastewater irrigated salad crops.

  5. Mosquitoes of the rice agroecosystem of Malaysia: species composition and their abundance in relation to rice farming

    International Nuclear Information System (INIS)

    Abu Hassan Ahmad; Che Salmah Md Rawi

    2002-01-01

    Mosquito abundance in relation to rice farming was studied in the Muda and the Kerian Irrigation Schemes. Mosquito larvae were collected using dippers for several growing seasons. Adult mosquitoes were collected by using human bait and cow bait and net trap at nights. Culex, Mansonia and Anopheles were the three genera of mosquito found in the rice agroecosystem. Four species of Mansonia were found biting on human bait. Culex mosquitoes were caught biting on human and cow baits. Culex tritaeniorhynchus, C pseudovishnui, C vishnui, C gelidus and C bitaeniorhynchus were the most common Culex mosquitoes found. Anoheles sinensis and A. peditaeniatus were the most dominant panopheline mosquitoes. High abundance of larvae and adult mosquitoes were observed during ploughing, planting, and tillering stages of rice farming. (Author)

  6. Rice Production Vulnerability to Climate Change in Indonesia: An Overview on Community-based Adaptation

    Science.gov (United States)

    Komaladara, A. A. S. P.; Budiasa, I. W.; Ambarawati, I. G. A. A.

    2015-12-01

    Rice remains to be a major crop and staple food in Indonesia. The task to ensure that rice production meets the demand of a growing population continues to engage the attention of national planners and policy makers. However, the adverse effects of climate change on agriculture production have presented Indonesia with yet another significant challenge. The exposure of rice crops to climate-related hazards such as temperature stress, floods, and drought, may lead to lower yield and self-sufficiency rate. This study explores the vulnerability of rice production to the effects of climate change in Indonesia. Considering the vast geographical span of the country and varying exposure, sensitivity, and adaptive capacity to climate change at regional level, this study emphasize the importance of community-based adaptation. Results from a simulation based on production and climate data from 1984 to 2014 indicates that rice production is sensitive to variation in growing season temperature and precipitation. A projection of these climate factors in 2050 has a significant impact on the major rice crop. To manage the impact of climate change, this study turns to the potential roles of farmer organizations, such as Subak, in adaptation strategies. The Subak in Bali is recognized for its cultural and organizational framework that highlights the sharing of knowledge and local wisdom in rice production. This is demonstrated by its efficient community-based irrigation management system, leading to sustainable rice production. Keywords: rice production, climate change, community-based adaptation, Indonesia

  7. Implications of Water Use and Water Scarcity Footprint for Sustainable Rice Cultivation

    Directory of Open Access Journals (Sweden)

    Thapat Silalertruksa

    2017-12-01

    Full Text Available Rice cultivation is a vital economic sector of many countries in Asia, including Thailand, with the well-being of people relying significantly on selling rice commodities. Water-intensive rice cultivation is facing the challenge of water scarcity. The study assessed the volumetric freshwater use and water scarcity footprint of the major and second rice cultivation systems in the Chao Phraya, Tha Chin, Mun, and Chi watersheds of Thailand. The results revealed that a wide range of freshwater use, i.e., 0.9–3.0 m3/kg of major rice and 0.9–2.3 m3/kg of second rice, and a high water use of rice was found among the watersheds in the northeastern region, like the Mun and Chi watersheds. However, the water scarcity footprint results showed that the second rice cultivation in watersheds, like in Chao Phraya and Tha Chin in the central region, need to be focused for improving the irrigation water use efficiency. The alternate wetting and drying (AWD method was found to be a promising approach for substituting the pre-germinated seed broadcasting system to enhance the water use efficiency of second rice cultivation in the central region. Recommendations vis-à-vis the use of the water stress index as a tool for agricultural zoning policy were also discussed.

  8. Genetic variation of 12 rice cultivars grown in Brunei Darussalam ...

    African Journals Online (AJOL)

    Dell

    2015-03-25

    Mar 25, 2015 ... Quantum yield for B. berminyak were unaffected and it showed the least reduction in growth parameters studied when expose to salinity stress. From both salinity tolerance and genetic variation investigations for these 12 cultivars, it may probably be better to intercross between Arat (moderately tolerant) ...

  9. The new species Enterobacter oryziphilus sp nov and Enterobacter oryzendophyticus sp nov are key inhabitants of the endosphere of rice

    NARCIS (Netherlands)

    Hardoim, Pablo Rodrigo; Nazir, Rashid; Sessitsch, Angela; Elhottova, Dana; Korenblum, Elisa; van Overbeek, Leonard Simon; van Elsas, Jan Dirk

    2013-01-01

    Background: Six independent Gram-negative, facultatively anaerobic, non-spore-forming, nitrogen-fixing rod-shaped isolates were obtained from the root endosphere of rice grown at the International Rice Research Institute (IRRI) and investigated in a polyphasic taxonomic study. Results: The strains

  10. The new species Enterobacter oryzaphilus sp. nov. and Enterobacter oryzaendophyticus sp. nov. are key inhabitants of the endosphere of rice.

    NARCIS (Netherlands)

    Hardoim, P.R.; Nazir, R.; Sessitsch, A.; Elhottova, D.; Korenblum, E.; Overbeek, van L.S.; Elsas, J.D.

    2013-01-01

    BACKGROUND: Six independent Gram-negative, facultatively anaerobic, non-spore-forming, nitrogen-fixing rod-shaped isolates were obtained from the root endosphere of rice grown at the International Rice Research Institute (IRRI) and investigated in a polyphasic taxonomic study.
    RESULTS: The

  11. Rice (Oryza sativa L.) containing the bar gene is compositionally equivalent to the nontransgenic counterpart.

    Science.gov (United States)

    Oberdoerfer, Regina B; Shillito, Raymond D; de Beuckeleer, Marc; Mitten, Donna H

    2005-03-09

    This publication presents an approach to assessing compositional equivalence between grain derived from glufosinate-tolerant rice grain, genetic event LLRICE62, and its nontransgenic counterpart. Rice was grown in the same manner as is common for commercial production, using either conventional weed control practices or glufosinate-ammonium herbicide. A two-season multisite trial design provided a robust data set to evaluate environmental effects between the sites. Statistical comparisons to test for equivalence were made between glufosinate-tolerant rice and a conventional counterpart variety. The key nutrients, carbohydrates, protein, iron, calcium, thiamin, riboflavin, and niacin, for which rice can be the principal dietary source, were investigated. The data demonstrate that rice containing the genetic locus LLRICE62 has the same nutritional value as its nontransgenic counterpart, and most results for nutritional components fall within the range of values reported for rice commodities in commerce.

  12. Evaluation of the effects of mulch on optimum sowing date and irrigation management of zero till wheat in central Punjab, India using APSIM

    OpenAIRE

    Balwinder-Singh,; Humphreys, E.; Gaydon, D.S.; Eberbach, P.L.

    2016-01-01

    Machinery for sowing wheat directly into rice residues has become more common in the rice-wheat systems of the north-west Indo-Gangetic Plains of South Asia, with increasing numbers of farmers now potentially able to access the benefits of residue retention. However, surface residue retention affects soil water and temperature dynamics, thus the optimum sowing date and irrigation management for a mulched crop may vary from those of a traditional non-mulched crop. Furthermore, the effects of s...

  13. The effects of irrigation and fertilization on specific gravity of loblolly pine

    Science.gov (United States)

    K. R. Love-Myers; Alexander Clark; L. R. Schimleck; P. M. Dougherty; R. F. Daniels

    2010-01-01

    The effects of two treatments, irrigation and fertilization, were examined on specific gravity (SG)-related wood properties of loblolly pine trees (Pinus taeda L.) grown in Scotland County, North Carolina. The effects on the core as a whole, on the juvenile core, on the mature core, and from year to year were all analyzed. The results indicate that fertilization...

  14. Evaluation of Irrigation Methods for Highbush Blueberry. I. Growth and Water Requirements of Young Plants

    Science.gov (United States)

    A study was conducted in a new field of northern highbush blueberry (Vaccinium corymbosum L. 'Elliott') to determine the effects of different irrigation methods on growth and water requirements of uncropped plants during the first 2 years after planting. The plants were grown on mulched, raised beds...

  15. Irrigation and cultivar effect on flax fiber and seed yield in the southeast USA

    Science.gov (United States)

    Flax (Linum usitatissimum L.) is a potential winter crop for the Southeast USA that can be grown for both seed and fiber. The objective of this research was to evaluate the effect of irrigation on flax straw, fiber, and seed yield of fiber-type and seed-type cultivars at different flax growth stage...

  16. Evaluation of subsurface drip irrigation design and management parameters for alfalfa

    NARCIS (Netherlands)

    Kandelous, M.M.; Kamai, T.; Vrugt, J.A.; Šimůnek, J.; Hanson, B.; Hopmans, J.W.

    2012-01-01

    Alfalfa is one of the most cultivated crops in the US, and is being used as livestock feed for the dairy, beef, and horse industries. About nine percent of that is grown in California, yet there is an increasing concern about the large amounts of irrigation water required to attain maximum yield. We

  17. Irrigation requirements for seed production of five Lomatium species in a semiarid environment

    Science.gov (United States)

    Clinton C. Shock; Erik B. G. Feibert; Alicia Rivera; Lamont D. Saunders; Nancy Shaw; Francis F. Kilkenny

    2016-01-01

    Seeds of native plants are needed for rangeland restoration in the Intermountain West. Many of these plants are rarely cultivated and relatively little is known about the cultural practices required for their seed production. Irrigation trials were conducted for five perennial Lomatium species over multiple years. Lomatium species grown at the Oregon State University...

  18. Sensing technologies for precision irrigation

    CERN Document Server

    Ćulibrk, Dubravko; Minic, Vladan; Alonso Fernandez, Marta; Alvarez Osuna, Javier; Crnojevic, Vladimir

    2014-01-01

    This brief provides an overview of state-of-the-art sensing technologies relevant to the problem of precision irrigation, an emerging field within the domain of precision agriculture. Applications of wireless sensor networks, satellite data and geographic information systems in the domain are covered. This brief presents the basic concepts of the technologies and emphasizes the practical aspects that enable the implementation of intelligent irrigation systems. The authors target a broad audience interested in this theme and organize the content in five chapters, each concerned with a specific technology needed to address the problem of optimal crop irrigation. Professionals and researchers will find the text a thorough survey with practical applications.

  19. Uptake of C-14 tagged acetate by rice in a paddy soil-to-rice plant system

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Nobuyoshi; Tagami, Keiko; Uchida, Shigeo [Research Center for Radiation Protection, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)

    2014-07-01

    Geological disposal of Transuranic (TRU) waste is planned to avoid radiation exposure to the public. One of the dominant nuclides contributing to the dose from TRU waste is C-14, which is long-lived and has very poor sorption properties on natural geological media. Therefore, there are some concerns regarding possible migration of C-14 to the living environments. For the public health safety, it is necessary to clarify pathways of C-14 to human beings in the environment. Intake of C-14 from food source is one of important pathways. In the present study, we examined transfer of C-14 to various parts of rice plant in a paddy soil-to-rice plant system. Rice seedlings in Wagner pots (n=12) were grown for about two months from 7 May 2012 under natural light. The grown plants were moved to a closed chamber on 5 July 2012. The rice plants were grown without water supply from 5 July 2012, and then one liter of C-14 tagged acetate (1.85 MBq) was supplied to the rice plants in the spiked group (n=8) just once on 9 July 2012. For the rice plants in the control group (n=4), uncontaminated water was supplied. These rice plants were air-dried after a harvest on 23 August 2012 and divided into four parts: white rice, bran, rice husk, and the stem and leaf part. The activities of C-14 in the divided parts and air-dried soil samples were determined with a liquid scintillation counting system. Radiocarbon was detected even in the rice plants of the control group. However, the C-14 activity in the soil of the control group was less than the detection limit (1.0 Bq/g). The C-14 activities for the control group decreased in the order of rice husk, bran, white rice, and the stem and leaf part. The detection of C-14 in the control group may be caused by the release of C-14 tagged carbon dioxide from the spiked group. That is, C-14 tagged acetate was converted to carbon dioxide by microbial activity in the spiked group, and then some of the released carbon dioxide was assimilated into

  20. Assessment of Potential Climate Change Effects on the Rice Yield and Water Footprint in the Nanliujiang Catchment, China

    Directory of Open Access Journals (Sweden)

    Mingzhi Yang

    2018-01-01

    Full Text Available The Nanliujiang catchment is one of major rice production bases of South China. Irrigation districts play an important role in rice production which requires a large quantity of water. There are potential risks on future climate change in response to rice production, agricultural irrigation water use and pollution control locally. The SWAT model was used to quantify the yield and water footprint (WF of rice in this catchment. A combined method of automatic and manual sub-basin delineation was used for the model setup in this work to reflect the differences between irrigation districts in yield and water use of rice. We validated our simulations against observed leaf area index, biomass and yield of rice, evapotranspiration and runoff. The outputs of three GCMs (GFDL-ESM2M, IPSL-CM5A-LR and HadGEM2-ES under three RCPs (RCP2.6, 4.5, 8.5 were fed to the SWAT model. The results showed that: (a the SWAT model is an ideal tool to simulate rice development as well as hydrology; (b there would be increases in rice yield ranged from +1.4 to +10.6% under climate projections of GFDL-ESM2M and IPSL-CM5A-LR but slight decreases ranged from −3.5 to −0.8% under that of HadGEM2-ES; (c the yield and WFs of rice displayed clear differences in the catchment, with a characteristic that high in the south and low in the north, mainly due to the differences in climatic conditions, soil quality and fertilization amount; (d there would be a decrease by 45.5% in blue WF with an increase by 88.1% in green WF, which could provide favorable conditions to enlarge irrigated areas and take technical measures for improving green water use efficiency of irrigation districts; (e a clear rise in future grey WF would present enormous challenges for the protection of water resources and environmental pollution control in this catchment. So it should be to improved nutrient management strategies for the agricultural non-point source pollution control in irrigation districts

  1. Colostomy irrigation: are we offering it enough?

    Science.gov (United States)

    Woodhouse, Fran

    This article discusses the use of irrigation for suitable colostomists and reasons why it can have a very positive effect on lifestyle. While it is evidence-based it also includes anecdotal tips from patients who irrigate. The suitability of patients to irrigate and ways to 'get started' with irrigation are discussed.

  2. Evaluation model development for sprinkler irrigation uniformity ...

    African Journals Online (AJOL)

    use

    Sprinkle and trickle irrigation. The. Blackburn Press, New Jersey, USA. Li JS, Rao MJ (1999). Evaluation method of sprinkler irrigation nonuniformity. Trans. CSAE. 15(4): 78-82. Lin Z, Merkley GP (2011). Relationships between common irrigation application uniformity indicators. Irrig Sci. Online First™, 27 January. 2011.

  3. Wireless sensor networks for irrigation management

    Science.gov (United States)

    Sustaining an adequate food supply for the world's population will require advancements in irrigation technology and improved irrigation management. Site-specific irrigation and automatic irrigation scheduling are examples of strategies to deal with declining arable land and limited fresh water reso...

  4. Condensation irrigation a system for desalination and irrigation

    International Nuclear Information System (INIS)

    Lindblom, J.; Nordell, B

    2006-01-01

    condensation irrigation is a system for both desalination and irrigation. The principles is that humidified air is let into an underground horizontal pipe system, where the air is cooled by the ground and humidity falls out as fresh water. The humidification could e.g. be achieved by evaporation of seawater in solar stills or any other heat source. By using drainage pipes for underground air transportation the water percolates into the soil, thereby irrigating the land. This study focuses on drinking water production, which means that humid air is led into plan pipes where the condensed water is collected at the pipe endings. Numerical simulations gave a study-state diurnal mean water production of 1.8 kg per meter of pipe over a 50 m pipe. Shorter pipes result in a greater mean production rate. Since the heat transfer of drainage pipes would be greater, current study indicates that condensation irrigation is a promising method for desalination and irrigation. Performed studies in condensation irrigation started at LTU in 2003. Current paper reports the initial theoretical work on the system.(Author)

  5. Greenhouse Gas Emissions and Global Warming Potential of Traditional and Diversified Tropical Rice Rotation Systems including Impacts of Upland Crop Management Practices i.e. Mulching and Inter-crop Cultivation

    Science.gov (United States)

    Janz, Baldur; Weller, Sebastian; Kraus, David; Wassmann, Reiner; Butterbach-Bahl, Klaus; Kiese, Ralf

    2016-04-01

    Paddy rice cultivation is increasingly challenged by irrigation water scarcity, while at the same time changes in demand (e.g. changes in diets or increasing demand for biofuels) will feed back on agricultural practices. These factors are changing traditional cropping patterns from flooded double-rice systems to the introduction of well-aerated upland crop systems in the dry season. Emissions of methane (CH4) are expected to decrease, while emissions of nitrous oxide (N2O) will increase and soil organic carbon (SOC) stocks will most likely be volatilized in the form of carbon dioxide (CO2). We measured greenhouse gas (GHG) emissions at the International Rice Research Institute (IRRI) in the Philippines to provide a comparative assessment of the global warming potentials (GWP) as well as yield scaled GWPs of different crop rotations and to evaluate mitigation potentials or risks of new management practices i.e. mulching and inter-crop cultivation. New management practices of mulching and intercrop cultivation will also have the potential to change SOC dynamics, thus can play the key role in contributing to the GWP of upland cropping systems. To present, more than three years of continuous measurement data of CH4 and N2O emissions in double-rice cropping (R-R) and paddy rice rotations diversified with either maize (R-M) or aerobic rice (R-A) in upland cultivation have been collected. Introduction of upland crops in the dry season reduced irrigation water use and CH4 emissions by 66-81% and 95-99%, respectively. Moreover, for practices including upland crops, CH4 emissions in the subsequent wet season with paddy rice were reduced by 54-60%. Although annual N2O emissions increased twice- to threefold in the diversified systems, the strong reduction of CH4 led to a significantly lower (pbalance but also with regard to soil fertility. New upland crop management practices where first implemented during land-preparation for dry season (July) 2015 where i) 6t/ha rice straw

  6. Genetic Loci Governing Grain Yield and Root Development under Variable Rice Cultivation Conditions

    Directory of Open Access Journals (Sweden)

    Margaret Catolos

    2017-10-01

    Full Text Available Drought is the major abiotic stress to rice grain yield under unpredictable changing climatic scenarios. The widely grown, high yielding but drought susceptible rice varieties need to be improved by unraveling the genomic regions controlling traits enhancing drought tolerance. The present study was conducted with the aim to identify quantitative trait loci (QTLs for grain yield and root development traits under irrigated non-stress and reproductive-stage drought stress in both lowland and upland situations. A mapping population consisting of 480 lines derived from a cross between Dular (drought-tolerant and IR64-21 (drought susceptible was used. QTL analysis revealed three major consistent-effect QTLs for grain yield (qDTY1.1, qDTY1.3, and qDTY8.1 under non-stress and reproductive-stage drought stress conditions, and 2 QTLs for root traits (qRT9.1 for root-growth angle and qRT5.1 for multiple root traits, i.e., seedling-stage root length, root dry weight and crown root number. The genetic locus qDTY1.1 was identified as hotspot for grain yield and yield-related agronomic and root traits. The study identified significant positive correlations among numbers of crown roots and mesocotyl length at the seedling stage and root length and root dry weight at depth at later stages with grain yield and yield-related traits. Under reproductive stage drought stress, the grain yield advantage of the lines with QTLs ranged from 24.1 to 108.9% under upland and 3.0–22.7% under lowland conditions over the lines without QTLs. The lines with QTL combinations qDTY1.3+qDTY8.1 showed the highest mean grain yield advantage followed by lines having qDTY1.1+qDTY8.1 and qDTY1.1+qDTY8.1+qDTY1.3, across upland/lowland reproductive-stage drought stress. The identified QTLs for root traits, mesocotyl length, grain yield and yield-related traits can be immediately deployed in marker-assisted breeding to develop drought tolerant high yielding rice varieties.

  7. Protocol for in vitro somatic embryogenesis and regeneration of rice (Oryza sativa L.).

    Science.gov (United States)

    Verma, Dipti; Joshi, Rohit; Shukla, Alok; Kumar, Pramod

    2011-12-01

    Development of highly efficient and reproducible plant regeneration system has tremendous potential to provide improved technology to assist in genetic transformation of indica rice cultivars for their further exploitation in selection. For the development of a highly reproducible regeneration system through somatic embryogenesis, mature embryos of highly popular rice cultivars i.e., Govind (for rainfed areas), Pusa Basmati-1 (aromatic basmati) and Jaya (for irrigated areas) were used. Optimum callus formation (%) to MS medium supplemented with 2, 4-D was obtained at 12.0 microM in Govind, 14.0 microM in Jaya and 15.0 microM in Pusa Basmati-1. All the cultivars showed good proliferation on MS medium without hormone. In Govind, highest embryogenic response was observed in MS medium supplemented with 2, 4-D (0.4 microM) + kinetin (0.4 microM), while in Pusa Basmati-1 with 2, 4-D (0.4 microM) + kinetin (2.0 microM) and in Jaya on hormone-free MS medium. Excellent embryo regeneration in Govind was observed on MS medium supplemented with low concentrations (1.1 microM) of BAP or hormone-free MS medium, while in Pusa Basmati-1 and Jaya embryogenesis was observed on MS medium supplemented with higher concentration of BAP (2.2 microM). Similarly, maximum plantlets with proliferated roots were observed in Govind on hormone-free MS medium, while in Pusa Basmati-1 and Jaya on MS medium supplemented with high concentration of NAA (4.0 microM). Developed plantlets were further successfully acclimatized and grown under pot culture up to maturity. Further the yield potential of in vitro developed plants was accessed at par to the direct seeded one under pot culture. Present, protocol standardizes somatic embryogenesis and efficient regeneration of agronomically important, high yielding and diverse indica rice cultivars which can be utilized as an efficient tool for molecular studies and genetic transformation in future.

  8. The application of parallel wells to support the use of groundwater for sustainable irrigation

    Science.gov (United States)

    Suhardi

    2018-05-01

    The use of groundwater as a source of irrigation is one alternative in meeting water needs of plants. Using groundwater for irrigation requires a high cost because of the discharge that can be taken is limited. In addition, the use of large groundwater can cause environmental damage and social conflict. To minimize costs, maintain quality of the environment and to prevent social conflicts, it is necessary to innovate in the groundwater taking system. The study was conducted with an innovation of using parallel wells. Performance is measured by comparing parallel wells with a single well. The results showed that the use of parallel wells to meet the water needs of rice plants and increase the pump discharge up to 100%. In addition, parallel wells can reduce the influence radius of taking of groundwater compared to single well so as to prevent social conflict. Thus, the use of parallel wells can support the achievement of the use of groundwater for sustainable irrigation.

  9. Arsenic contamination of soils and agricultural plants through irrigation water in Nepal

    International Nuclear Information System (INIS)

    Dahal, B.M.; Fuerhacker, M.; Mentler, A.; Karki, K.B.; Shrestha, R.R.; Blum, W.E.H.

    2008-01-01

    This study monitored the influence of arsenic-contaminated irrigation water on alkaline soils and arsenic uptake in agricultural plants at field level. The arsenic concentrations in irrigation water ranges from -1 where the arsenic concentrations in the soils were measured from 6.1 to 16.7 mg As kg -1 . The arsenic content in different parts of plants are found in the order of roots > shoots > leaves > edible parts. The mean arsenic content of edible plant material (dry weight) were found in the order of onion leaves (0.55 mg As kg -1 ) > onion bulb (0.45 mg As kg -1 ) > cauliflower (0.33 mg As kg -1 ) > rice (0.18 mg As kg -1 ) > brinjal (0.09 mg As kg -1 ) > potato ( -1 ). - The arsenic content in soil and plants is influenced by the degree of arsenic amount in irrigated water

  10. Sample sufficiency of chinese pink grown in different substrates

    Directory of Open Access Journals (Sweden)

    Sidinei José lopes

    2016-04-01

    Full Text Available The cravina is an excellent plant to build up gardens due to its early flowering, abundant flowering and great performance in spring and autumn. The objective was to estimate the sample size for plant chinese pink, grown on different substrates, and check the variability of the sample size between growth parameters and production and substrates. They used seven treatments (substrates: S1 = 50% soil + 50% rice husk ash; S2 = 80% soil + 20% earthworm castings; S3 = 80% rice husk ash + 20% earthworm castings; S4 = 40% soil + 40% rice husk ash + 20% earthworm castings; S5 = 100% peat; S6 = 100% commercial substrate Mecplant®; S7 = 50% peat + 50% rice husk ash, with 56 repetitions each, totaling 392 plants of garden pink, which was evaluated in 17 of growth and production parameters. The methodology used to bootstrap resampling, with replacement, for each character within each substrate with predetermined error: 5, 10, 20 and 40% of the average (D%. To a 95% confidence interval, with D = 20%, the substrate 50% soil and 50% of rice husk ash had the largest sample size 11 characters; when comparing the characters , the number of flower buds had the highest sample size on average 113 plants. Using samples of 44 plant chinese pink for commercial substrate Mecplant® meet the lower precisions or equal to 20% for all variables. There is variation in sample size in relation to the substrate used and the variable evaluated in chinese pink plants.

  11. Morphogenetic, structural and productive traits of buffel grass under different irrigation regimes

    Directory of Open Access Journals (Sweden)

    Maria Janiele Ferreira Coutinho

    2015-06-01

    Full Text Available The water restriction conditions in the Brazilian semiarid region are one of the most limiting factors to the establishment and yield of forage grasses. This study aimed to evaluate the effect of different irrigation regimes on morphogenetic, structural and productive traits of buffel grass. Arandomized blocks design, with five treatments and six replications, was used. Treatments consisted of five irrigation regimes, corresponding to the intervals of 2, 4, 6, 8 and 10 days. The traits analyzed were: leaf emergence rate, phyllochron, leaf and stem elongation rate, leaf senescence rate, final leaf length, number of green leaves per tiller, number of tillers, stem height, leaf/stem ratio, leaf area index, dry mass of green leaf and stem, dry mass of green, dead and total forage, root dry mass, dry mass and green dry mass/dead dry mass ratio. The final leaf length and dead forage dry mass were not affected by the irrigation regimes. The leaf/stem ratio followed a quadratic model, maintaining the value of 0.51 up to the irrigation regime of four days. The other morphological, structural and productive traits decreased linearly with increasing irrigation frequencies. The irrigation intervals promoted reductions in the morphological, structural and productive parameters of buffel grass, when grown under greenhouse conditions. The irrigation regime of 2 days stands out as the least restrictive to the development of buffel grass.

  12. Uptake and Accumulation of Pharmaceuticals in Lettuce Under Surface and Overhead Irrigations

    Science.gov (United States)

    Bhalsod, G.; Chuang, Y. H.; Jeon, S.; Gui, W.; Li, H.; Guber, A.; Zhang, W.

    2015-12-01

    Pharmaceuticals and personal care products are being widely detected in wastewater and surface waters. As fresh water becomes scarcer, interests in using reclaimed water for crop irrigation is intensified. Since reclaimed waters often carry trace levels of pharmaceuticals, accumulation of pharmaceuticals in food crops could increase the risk of human exposure. This study aims to investigate uptake and accumulations of pharmaceuticals in greenhouse-grown lettuce under contrasting irrigation practices (i.e., overhead and surface irrigations). Lettuce was irrigated with water spiked with 11 commonly used pharmaceuticals (acetaminophen, caffeine, carbamazepine, sulfadiazine, sulfamethoxazole, carbadox, trimethoprim, lincomycin hydrochloride, oxytetracycline hydrochloride, monensin sodium, and tylosin). Weekly sampling of lettuce roots, shoots, and soils were continued for 5 weeks, and the samples were freeze dried, extracted for pharmaceuticals and analyzed by LC-MS/MS. Preliminary results indicate that higher concentrations of pharmaceuticals were found in overhead irrigated lettuce compared to surface irrigated lettuce. For carbamezapine, sulfadiazine, trimethoprim, oxytetracycline, and monensin sodium, their concentrations generally increased in lettuce shoots in the overhead treatment over time. However, acetaminophen was found at higher concentrations in both shoots and roots, indicating that acetaminophen can be easily transported in the plant system. This study provides insight on developing better strategies for using reclaimed water for crop irrigations, while minimizing the potential risks of pharmaceutical contamination of vegetables.

  13. Alfalfa Water Use and Yield under Different Sprinkler Irrigation Regimes in North Arid Regions of China

    Directory of Open Access Journals (Sweden)

    Yan Li

    2017-08-01

    Full Text Available Alfalfa (Medicago sativa is one of the major crops grown in Northern China in recent years, however, the current serious water shortage conditions present a challenge to the growth of this crop, especially if efficient use of water is considered in forage production for sustainability. This study aimed to evaluate alfalfa productivity and water use efficiency (WUE under different sprinkler irrigation levels. This experiment was conducted at Shiyanghe Experimental Station for Water-Saving in Agriculture and Ecology of China Agricultural University in Wuwei, Gansu, China, over a period of two years. There were three irrigation treatments: A1: 100% measured evapotranspiration (ETc of alfalfa; A2: irrigation amount was 66% of A1; A3: irrigation amount was 33% of A1; and a control of A4: no irrigation during the growing season. A randomized block design with three replications were applied. The results showed that the ETc and forage yield of alfalfa decreased, while WUE and crude protein (CP increased with the decreasing irrigation amounts. The seasonal average ETc and yield ranged from 412 mm to 809 mm and from 11,577 to 18,636 kg/ha, respectively, under different irrigation levels. The highest yields were obtained from the first growth period in all treatments in both years, due to the winter irrigation and the longest growth period. Alfalfa grown under lesser irrigation treatment conditions had higher variability in ETc and yield, mainly due to the variability in the amount of rainfall during the growth period. The seasonal average WUE of treatments ranged from 22.78 to 26.84 kg/(mm·ha, and the highest WUE was obtained at the first growth period, regardless of treatments. Seasonal average CP content ranged from 18.99% to 22.99%. A significant linear relationship was found between yield and ETc or irrigation amount, and the fitting results varied between growth periods and years. The present results also implied that winter irrigation provided the

  14. Comparative study of nitrogen fertilizer use efficiency of cotton grown under conventional and fertigation practices using 15N methodology

    International Nuclear Information System (INIS)

    Janat, M.; Somi, G.

    2002-01-01

    Nitrogen fertilization and irrigation methods are the key factors of yield increase. With proper management of these two factors a good production and protection of the environment could be attained at the same time. Field experiments were carried out at Hama (Tezeen's Agricultural Research Station) for four consecutive years 1995=1998. The objectives of this study were: Assessment of nitrogen fertilizer use efficiency (NFUE) under conventional and fertigation practices; Nitrogen requirements of cotton crop grown under fertigation practices: Comparative study of water use efficiency (WUE), and seed cotton yield of cotton crop grown under conventional and drip irrigation. Treatments consisted of five nitrogen rates for the fertigated cotton crop (0, 60, 120, 180 and 240 kg N ha -1 ). While of the surface irrigated cotton treatment only one recommended rate by MAAR was applied (180 kg N ha -1 ). Irrigation methods and N treatments were arranged in RBD. The soil water content and available soil nitrogen were monitored according to the standard procedures. The results revealed that fertigation of cotton under the given circumstances improved water use efficiency, nitrogen use efficiency, seed cotton yield, dry matter production, earliness and in some cases lint properties. Under fertigation practices 35-55% of the irrigation water was saved in comparison with surface irrigated cotton grown under the same condition. The seed cotton yield was increased by more than 50% relatively to the surface irrigated cotton. Furthermore, water use efficiency of the fertigated cotton was increased by almost 90 %. (author)

  15. N2-fixation in fababean (vicia faba l.) grown in saline and non saline conditions using 15N tracer technique

    International Nuclear Information System (INIS)

    Khalifa, Kh.; Kurdali, F.

    2002-09-01

    A pot experiment was conducted to study the performance of growing fababean and barley under saline conditions, in terms of, dry matter yield, total nitrogen and, percentages and amount of N derived from soil, fertilizer and atmosphere using 15 N isotope dilution method. Three saline treatments were performed: First, plants were grown in saline soil and irrigated with saline water (Ws Ss), Second, Plants were grown in saline soil and irrigated with saline water (Ws Ss); and Third, Plants grown in non saline soil and irrigated with saline water (Ws Sn). Furthermore, a control treatment was performed by using non-saline soil and non-saline water (Wn Sn). The different salinity treatments reduced plant growth and the reduction was more pronounced in fababean than in barley. However, under conditions of either saline soil-soft irrigation water or non saline soil-salty irrigation water, the relative growth reduction did not exceed 50% of the control; whereas, a significant negative effect was obtained when plants were grown under completely saline conditions of both soil and irrigation water. Percentage of N 2 -fixed (% Ndfa) was not negatively affected by saline conditions. However, our results clearly demonstrated that the effect of salinity in fababean was more evident on plant growth than on N 2 -fixing activity. Further studies are needed to obtain more salt tolerant faba bean genotypes in terms of growth and yield. This could be simultaneously improve yield and N 2 -fixation under sever saline conditions. (author)

  16. Substrates and irrigation levels for growing desert rose in pots

    Directory of Open Access Journals (Sweden)

    Ronan Carlos Colombo

    Full Text Available ABSTRACT In the past decades, desert rose has become a very popular ornamental plant, especially among collectors, due to its exotic and sculptural forms. However, it has been grown on a commercial scale only recently, and little is known about how to best manage it as a container-grown plant, or even which potting medium (substrate to recommend. Therefore, the aim of this study was to investigate the interactions between potting media and irrigation levels for growing desert rose as a potted ornamental plant. The experiment was conducted in a greenhouse using a 6 x 2 factorial arrangement with six replications, six potting media and two irrigation levels. The mixes were characterized by measuring their physical properties, specifically the density and water retention capacity (WRC, as well as chemical properties, such as the pH and electrical conductivity (EC. After 210 days, plant growth and plant water consumption were evaluated and measured. A lower dry density for the vermiculite mixes was observed in comparison to that for the sand mixes. However, WRC ranged from 428 to 528 mL L-1 among the mixes, values considered close to ideal. In general, plant growth exhibited higher increases in mixes consisting of coconut fiber + sand or vermiculite, regardless of the irrigation level. Mixes of vermiculite + coconut fiber and sand + coconut fiber can be used to grow desert rose in pots, as long as irrigation is used to maintain the moisture content of the potting medium (mix between 60-70% and 80-90% of the WRC.

  17. Genomic prediction accounting for genotype by environment interaction offers an effective framework for breeding simultaneously for adaptation to an abiotic stress and performance under normal cropping conditions in rice

    OpenAIRE

    Ahmadi, Nourollah; Cao, Tuong-Vi; Valé, Giampiero; Bartholomé, Jérôme; Hassen, Manel

    2018-01-01

    Developing rice varieties adapted to alternate wetting and drying water management is crucial for the sustainability of irrigated rice cropping systems. Here we report the first study exploring the feasibility of breeding rice for adaptation to alternate wetting and drying using genomic prediction methods that account for genotype by environment interactions. Two breeding populations (a reference panel of 284 accessions and a progeny population of 97 advanced lines) were evaluated under alter...

  18. Rice (Oryza) hemoglobins

    Science.gov (United States)

    Hemoglobins (Hbs) corresponding to non-symbiotic (nsHb) and truncated (tHb) Hbs have been identified in rice (Oryza). This review discusses the major findings from the current studies on rice Hbs. At the molecular level, a family of the nshb genes, consisting of hb1, hb2, hb3, hb4 and hb5, and a sin...

  19. Golden Rice is an effective source of vitamin A1234

    Science.gov (United States)

    Qin, Jian; Dolnikowski, Gregory G; Russell, Robert M; Grusak, Michael A

    2009-01-01

    Background: Genetically engineered “Golden Rice” contains up to 35 μg β-carotene per gram of rice. It is important to determine the vitamin A equivalency of Golden Rice β-carotene to project the potential effect of this biofortified grain in rice-consuming populations that commonly exhibit low vitamin A status. Objective: The objective was to determine the vitamin A value of intrinsically labeled dietary Golden Rice in humans. Design: Golden Rice plants were grown hydroponically with heavy water (deuterium oxide) to generate deuterium-labeled [2H]β-carotene in the rice grains. Golden Rice servings of 65–98 g (130–200 g cooked rice) containing 0.99–1.53 mg β-carotene were fed to 5 healthy adult volunteers (3 women and 2 men) with 10 g butter. A reference dose of [13C10]retinyl acetate (0.4–1.0 mg) in oil was given to each volunteer 1 wk before ingestion of the Golden Rice dose. Blood samples were collected over 36 d. Results: Our results showed that the mean (±SD) area under the curve for the total serum response to [2H]retinol was 39.9 ± 20.7 μg·d after the Golden Rice dose. Compared with that of the [13C10]retinyl acetate reference dose (84.7 ± 34.6 μg·d), Golden Rice β-carotene provided 0.24–0.94 mg retinol. Thus, the conversion factor of Golden Rice β-carotene to retinol is 3.8 ± 1.7 to 1 with a range of 1.9–6.4 to 1 by weight, or 2.0 ± 0.9 to 1 with a range of 1.0–3.4 to 1 by moles. Conclusion: β-Carotene derived from Golden Rice is effectively converted to vitamin A in humans. This trial was registered at clinicaltrials.gov as NCT00680355. PMID:19369372

  20. Impact Of Different Time Planting In Soybeans And Neem Seed Extract Application To Insect Population On Rice Field

    Directory of Open Access Journals (Sweden)

    Tamrin Abdullah

    2015-08-01

    Full Text Available Abstract The purpose of research is to study impact of different time planting of soybean and neem seed extract application to pest insect population on rice field. The research was used Random Block Design in three treatment of insecticides application i.e neem seed extract together with rice planting neem seed extract on soybean 17 days after rice planting synthetic insecticides on 17 days after rice planting Delthametrin on soybean and Chlorpirifos on rice respectively. Research was conducted in rice fields with irrigation channels. The land area is 0.8 hectares with extensive experiments each rice terraces approximately 900 m2 with separate by rice terraces for every treatment. Each treatment consisted of three groups and using nine rice terraces. Samples of the rice plant population is 25 plants per sample unit. The results was showed treatment by neem seed extract with different time planting of soybeans able to reduce number of pest insects populations such as N. virescens 80.38 N. lugens 67.17 S. incertulas 66.5 and L. oratorius 93.46 when compared to treatment with synthetic insecticides Delthamethrin and Chlorpyrifos.

  1. Biodiversity Conservation in Rice Paddies in China: Toward Ecological Sustainability

    Directory of Open Access Journals (Sweden)

    Yufeng Luo

    2014-09-01

    Full Text Available Rice paddies are artificial wetlands that supply people with food and provide wildlife with habitats, breeding areas, shelters, feeding grounds and other services, and rice paddies play an important part in agricultural ecological systems. However, modern agricultural practices with large-scale intensive farming have significantly accelerated the homogenization of the paddy field ecosystem. Modern agriculture mostly relies on chemically-driven modern varieties and irrigation to ensure high production, resulting in the deterioration and imbalance of the ecosystem. Consequently, outbreaks of diseases, insects and weeds have become more frequent in paddy fields. This paper describes the current situation of rice paddy biodiversity in China and analyzes the community characteristics of arthropods and weedy plants. Meanwhile, we discuss how biodiversity was affected by modern agriculture changes, which have brought about a mounting crisis threatening to animals and plants once common in rice paddies. Measures should be focused to firstly preventing further deterioration and, then, also, promoting restoration processes. Ecological sustainability can be achieved by restoring paddy field biodiversity through protecting the ecological environment surrounding the paddy fields, improving paddy cropping patterns, growing rice with less agricultural chemicals and chemical fertilizers, constructing paddy systems with animals and plants and promoting ecolo