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Individual effect of different field scale management interventions for water saving in rice viz. changing date of transplanting, cultivar and irrigation schedule on yield, water saving and water productivity is well documented in the literature. However, little is known about their integrated effect. To study that, field experimentation and modeling approach was used. Field experiments were conducted for 2 years (2006 and 2007) at Punjab Agricultural University Farm, Ludhiana on a deep alluvial loamy sand Typic Ustipsamment soils developed under hyper-thermic regime. Treatments included three dates of transplanting (25 May, 10 June and 25 June), two cultivars (PR 118 inbred and RH 257 hybrid) and two irrigation schedules (2-days drainage period and at soil water suction of 16 kPa). The model used was CropSyst, which has already been calibrated for growth (periodic biomass and LAI) of rice and soil water content in two independent experiments. The main findings of the field and simulation studies conducted are compared to any individual, integrated management of transplanting date, cultivar and irrigation, sustained yield (6.3-7.5 t ha−1) and saved substantial amount of water in rice. For example, with two management interventions, i.e. shifting of transplanting date to lower evaporative demand (from 5 May to 25 June) concomitant with growing of short duration hybrid variety (90 days from transplanting to harvest), the total real water saving (wet saving) through reduction in evapotranspiration (ET) was 140 mm, which was almost double than managing the single, i.e. 66 mm by shifting transplanting or 71 mm by growing short duration hybrid variety. Shifting the transplanting date saved water through reduction in soil water evaporation component while growing of short duration variety through reduction in both evaporation and transpiration components of water balance. Managing irrigation water schedule based on soil water suction of 16 kPa at 15-20 cm soil depth, compared to 2-day drainage, did not save water in real (wet saving), however, it resulted into apparent water saving (dry saving). The real crop water productivity (marketable yield/ET) was more by 17% in 25th June transplanted rice than 25th May, 23% in short duration variety than long and 2% in irrigation treatment of 16 kPa soil water suction than 2-days drainage. The corresponding values for the apparent crop water productivity (marketable yield/irrigation water applied) were 16, 20 and 50%, respectively. Pooled experimental data of 2 years showed that with managing irrigation scheduling based on soil water suction of 16 kPa at 15-20 cm soil depth, though 700 mm irrigation water was saved but the associated yield was reduced by 277 kg ha−1.  相似文献   
3.
Malignant catarrhal fever (MCF) is a fatal herpesvirus infection of domestic and wild ruminants, with a short and dramatic clinical course characterized primarily by high fever, severe depression, swollen lymph nodes, salivation, diarrhea, dermatitis, neurological disorders, and ocular lesions often leading to blindness. In the present study, fatal clinical cases of sheep associated malignant catarrhal fever (SA-MCF) were identified in cattle in the state of Karnataka. These cases were initially presented with symptoms of diarrhea, respiratory distress, conjunctivitis, and nasal discharges. Laboratory diagnosis confirmed the detection of ovine herpesvirus-2 (OvHV-2) genome in the peripheral blood samples of two ailing animals. The blood samples collected subsequently from sheep of the neighboring areas also showed presence of OvHV-2 genome indicating a nidus of infection in the region. The positive test results were further confirmed by nucleotide sequencing of the OIE approved portion of tegument gene as well as complete ORF8 region of the OvHV-2 genome. Phylogenetic analysis based on the sequence of the latter region indicated close genetic relationship with other OvHV-2 reported elsewhere in the world.  相似文献   
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Application of high pres sure at 250 degrees C irreversibly dehydrated five inorganic compounds containing molecular water to lower hydrates or to anhydrous forms. Compression at 250 degrees C also lead to ten new reversible phase transformations in another group of nine hydrates. Maximum pressure applied was 22.6 kilobars.  相似文献   
6.
Femtosecond laser pulses and coherent two-phonon Raman scattering were used to excite KTaO3 into a squeezed state, nearly periodic in time, in which the variance of the atomic displacements dips below the standard quantum limit for half of a cycle. This nonclassical state involves a continuum of transverse acoustic modes that leads to oscillations in the refractive index associated with the frequency of a van Hove singularity in the phonon density of states.  相似文献   
7.
Leaching of pesticides in tea brew.   总被引:2,自引:0,他引:2  
A cup of tea that cheers can also be an important route of human exposure to pesticide residues. It is important to evaluate the percent transfer of pesticide residue from dried (made) tea to tea infusion, as tea is subjected to an infusion process prior to human consumption. To investigate the pesticide translocation, 13 pesticides commonly used on tea were studied by subjection of fortified teas to infusion. Analytes of interest were quantified by gas-liquid chromatography with nitrogen-phosphorus and electron capture detectors. Interestingly, water solubility of pesticides did not necessarily indicate a shift of residues toward their preferential accumulation in infusion. The pesticides with larger partition coefficient (K(ow)) values remained nonextractable in infusing water. Further, boiling for longer periods (extended brewing time) resulted in higher transfer of pesticides to tea brew.  相似文献   
8.
SOIL STERILIZATION WITH METHYL BROMIDE TO CONTROL SOIL NEMATODES   总被引:2,自引:2,他引:0  
N. G. Hague  Usha  Sood 《Plant pathology》1963,12(2):88-90
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9.
Various enzymes of the tricarboxylic acid cycle (TCA) viz., aconitase (E.C. 4.2.1.3), isocitrate dehydrogenase (E.C. 1.1.1.42), succinate dehydrognease (E.C. 1.3.99.1), fumarate reductase (NADH: fumarate oxido-reductase), fumarase (E.C. 4.2.1.2) and maltate dehydrogenase (E.C. 1.1.1.37) were detected in adult Haemonchus contortus (Nematoda: Trichostrongylidae), in vitro. Low activities of aconitase and isocitrate dehydrogenase suggested that the TCA cycle has a minor function and the pathway of CO2 fixation is the major pathway in the energy metabolism of the parasite. In vitro incubation in Tyrode's solution had no significant effect on TCA cycle enzymes and the worm was able to maintain normal metabolism for 12 h.The effects of dl-tetramisole and rafoxanide on various enzymes of the TCA cycle were studied in adult H. contortus. At 50 μg ml?1 varying degrees of succinate dehydrogenase and fumarate reductase activities were observed. At the same concentration, the activities of other enzymes remained unaltered.  相似文献   
10.
The present study aimed at selection of efficient bacterial isolates with multiple plant growth-promoting (PGP) traits at variable doses of chemical fertilizers for enhanced wheat productivity and sustenance of soil health. Ten bacterial isolates from wheat (rhizosphere soil and root endosphere) were screened for PGP traits (indole acetic acid, phosphate solubilization, siderophore production, and ammonia production). Only three isolates (B2, SIR1, and BIS2) possessed all PGP traits. Net house evaluation of these isolates at graded doses of chemical fertilizers revealed that the potential of B2 isolate is significantly superior for enhancing wheat yield and soil properties. On the basis of 16S rDNA analysis, the potential isolate (B2) was identified as Serratia marcescens. Conjoint use of the B2 isolate at 80% recommended doses of fertilizers (RDF) significantly increased wheat growth and saved 18 kg nitrogen and 10 kg phosphorous on per hectare basis. The developed module not only increases profitability but also protects the environment and sustains soil health.  相似文献   
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