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Liaqat U.W.,Hanyang University | Choi M.,Sungkyunkwan University | Awan U.K.,International Center for Agriculture Research in the Dry Areas
Hydrological Processes | Year: 2015

Strategic planning of optimal water use requires an accurate assessment of actual evapotranspiration (ETa) to understand the environmental and hydrological processes of the world's largest contiguous irrigation networks, including the Indus Basin Irrigation System (IBIS) in Pakistan. The Surface Energy Balance System (SEBS) has been used successfully for accurate estimations of ETa in different river basins throughout the world. In this study, we examined the application of SEBS using publically available remote sensing data to assess spatial variations in water consumption and to map water stress from daily to annual scales in the IBIS. Ground-based ETa was calculated by the advection-aridity method, from nine meteorological sites, and used to evaluate the intra-annual seasonality in the hydrological year 2009-2010. In comparison with the advection-aridity, SEBS computed daily ETa was slightly underestimated with a bias of -0.15mmday-1 during the kharif (wet; April-September) season, and it was overestimated with a bias of 0.23mmday-1 in the rabi (dry; October-March) season. Monthly values of the ETa estimated by SEBS were significantly (P<0.05) controlled by mean air temperature and rainfall, among other climatological variables (relative humidity, sunshine hours and wind speed). Because of the seasonal (kharif and rabi) differences in the water and energy budget in the huge canal command areas of the IBIS, ETa and rainfall were positively correlated in the kharif season and were negatively correlated during the rabi season. In addition, analysis of the evaporation process showed that mixed-cropping and rice-wheat dominated areas had lower and higher water consumption rates, respectively, in comparison with other cropping systems in the basin. Basin areas under water stress were identified by means of spatial variations in the relative evapotranspiration, which had an average value of 0.59 and 0.42 during the kharif and the rabi seasons, respectively. The hydrological parameters used in this study provide useful information for understanding hydrological processes at different spatial and temporal scales. Results of this study further suggest that the SEBS is useful for evaluation of water resources in semi-arid to arid regions over longer periods, if the data inputs are carefully handled. © 2014 John Wiley & Sons, Ltd. Source

Kumari S.G.,International Center for Agriculture Research in the Dry Areas | Rodoni B.,Australian Department of Primary Industries and Fisheries | Vetten H.-J.,Julius Kuhn Institute | Loh M.H.,Australian Department of Primary Industries and Fisheries | And 4 more authors.
Journal of Phytopathology | Year: 2010

A virus disease of faba bean (Vicia faba L.) in China, characterized by leaf yellowing and rolling and plant stunting, was shown to be caused by a virus of the genus Nanovirus based on serological reactions to nanovirus-specific monoclonal antibodies and the generation of polymerase chain reaction amplicons using nanovirus-specific primers. To identify the faba bean-infecting nanovirus, regions of the DNA components encoding the master replication initiator protein and capsid protein of two nanovirus isolates from China were cloned, sequenced and compared with those of other members of the genus Nanovirus. The two Chinese virus isolates shared nucleotide sequence identities ranging from 95 to 98% with the type isolate of Milk vetch dwarf virus (MDV) from Japan. They were thus identified as isolates of MDV, a virus so far known to cause important diseases of legumes in Japan. This is the first record of MDV-infecting faba bean in China. © 2009 Blackwell Verlag GmbH. Source

Kumar M.,Banaras Hindu University | Singh R.K.,International Center for Agriculture Research in the Dry Areas | Murari V.,Banaras Hindu University | Singh A.K.,Banaras Hindu University | And 2 more authors.
Atmospheric Research | Year: 2016

Diwali-specific firework induced particle pollution was measured in terms of aerosol mass loading, type, optical properties and vertical distribution. Entire nation exhibited an increase in particulate concentrations specifically in Indo-Gangetic Plain (IGP). Aerosol surface mass loading at middle IGP revealed an increase of 56-121% during festival days in comparison to their background concentrations. Space-borne measurements (Aqua and Terra-MODIS) typically identified IGP with moderate to high AOD (0.3-0.8) during pre-festive days which transmutes to very high AOD (0.4-1.8) during Diwali-day with accumulation of aerosol fine mode fractions (0.3-1.0). Most of the aerosol surface monitoring stations exhibited increase in PM2.5 especially on Diwali-day while PM10 exhibited increase on subsequent days. Elemental compositions strongly support K, Ba, Sr, Cd, S and P to be considered as firework tracers. The upper and middle IGP revealed dominance of absorbing aerosols (OMI-AI: 0.80-1.40) while CALIPSO altitude-orbit-cross-section profiles established the presence of polluted dust which eventually modified with association of smoke and polluted continental during extreme fireworks. Diwali-specific these observations have implications on associating fireworks induced particle pollution and human health while inclusion of these observations should improve regional air quality model. © 2016 Elsevier B.V. Source

Ahmad W.,International Water Management Institute IWMI | Fatima A.,University of Stockholm | Awan U.K.,International Center for Agriculture Research in the Dry Areas | Anwar A.,International Water Management Institute IWMI
Global and Planetary Change | Year: 2014

The Indus basin of Pakistan is vulnerable to climate change which would directly affect the livelihoods of poor people engaged in irrigated agriculture. The situation could be worse in middle and lower part of this basin which occupies 90% of the irrigated area. The objective of this research is to analyze the long term meteorological trends in the middle and lower parts of Indus basin of Pakistan. We used monthly data from 1971 to 2010 and applied non-parametric seasonal Kendal test for trend detection in combination with seasonal Kendall slope estimator to quantify the magnitude of trends. The meteorological parameters considered were mean maximum and mean minimum air temperature, and rainfall from 12 meteorological stations located in the study region. We examined the reliability and spatial integrity of data by mass-curve analysis and spatial correlation matrices, respectively. Analysis was performed for four seasons (spring-March to May, summer-June to August, fall-September to November and winter-December to February). The results show that max. temperature has an average increasing trend of magnitude +. 0.16, +. 0.03, 0.0 and +. 0.04. °C/decade during all the four seasons, respectively. The average trend of min. temperature during the four seasons also increases with magnitude of +. 0.29, +. 0.12, +. 0.36 and +. 0.36. °C/decade, respectively. Persistence of the increasing trend is more pronounced in the min. temperature as compared to the max. temperature on annual basis. Analysis of rainfall data has not shown any noteworthy trend during winter, fall and on annual basis. However during spring and summer season, the rainfall trends vary from -. 1.15 to +. 0.93 and -. 3.86 to +. 2.46. mm/decade, respectively. It is further revealed that rainfall trends during all seasons are statistically non-significant. Overall the study area is under a significant warming trend with no changes in rainfall. © 2014 Elsevier B.V.All rights reserved. Source

Goutam U.,Lovely Professional University | Kukreja S.,Lovely Professional University | Yadav R.,Guru Jambheshwar University of Science and Technology | Salaria N.,Lovely Professional University | And 2 more authors.
Frontiers in Microbiology | Year: 2015

Wheat accounts for 19% of the total production of major cereal crops in the world. In view of ever increasing population and demand for global food production, there is an imperative need of 40-60% increase in wheat production to meet the requirement of developing world in coming 40 years. However, both biotic and abiotic stresses are major hurdles for attaining the goal. Among the most important diseases in wheat, fungal diseases pose serious threat for widening the gap between actual and attainable yield. Fungal disease management, mainly, depends on the pathogen detection, genetic and pathological variability in population, development of resistant cultivars and deployment of effective resistant genes in different epidemiological regions. Wheat protection and breeding of resistant cultivars using conventional methods are time-consuming, intricate and slow processes. Molecular markers offer an excellent alternative in development of improved disease resistant cultivars that would lead to increase in crop yield. They are employed for tagging the important disease resistance genes and provide valuable assistance in increasing selection efficiency for valuable traits via marker assisted selection (MAS). Plant breeding strategies with known molecular markers for resistance and functional genomics enable a breeder for developing resistant cultivars of wheat against different fungal diseases. © 2015 Goutam, Kukreja, Yadav, Salaria, Thakur and Goyal. Source

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