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1.
R. K. NARESH S. S. TOMAR Dipender KUMAR Samsher Purushottam S. P. SINGH Ashish DWIVEDI Vineet KUMAR 《水稻科学》2014,21(3):170-180
In recent years, conventional rice production technologies have been leading to deterioration of soil health and declining farm profitability due to high inputs of water and labor. Conservation agriculture(CA) based resource-conserving technologies i.e. zero-tillage(ZT), raised-bed planting and direct-seeded rice(DSR) have shown promise as alternatives to conventional production technologies to overcome these problems. Present study was undertaken during 2009–2012 to establish an understanding of how permanent raised bed cropping system could be practiced to save water at the field application level to improve water productivity and also have the capability to enhance productivity, profitability and soil physical quality. The results showed that among different crop establishment techniques, conventional-tilled puddle transplanted rice(CT-TPR) required 14%-25% more water than other techniques. Compared with the CT-TPR system, zero till direct-seeded rice(ZT-DSR) consumed 6%–10% less water with almost equal system productivity and demonstrated higher water productivity. Wide raised beds saved about 15%–24% water and grain yield decrease of about 8%. Direct-seeded rice after ZT or reduced tillage or on unpuddled soil provided more net income than CT-TPR. The CTTPR system had higher bulk density and penetration resistance due to compaction caused by the repeated wet tillage in rice. The steady-state infiltration rate and soil aggregation( 0.25 mm) were higher under permanent beds and ZT and lower in the CT-TPR system. Under CT-TPR, soil aggregation was static across seasons, whereas it improved under no-till and permanent beds. Similarly, mean weight diameter of aggregates was higher under ZT and permanent beds and increased over time. The study reveals that to sustain the rice productivity, CA-based planting techniques can be more viable options. However, the long-term effects of these alternative technologies need to be studied under varying agro-ecologies in western Uttar Pradesh, India. 相似文献
2.
Roop Kishore Ashish Dwivedi Raghuvir Singh R. K. Naresh Vineet Kumar Priyanka Bankoti Dinesh Kumar Sharma Nishant Yadav 《Paddy and Water Environment》2017,15(1):49-58
Weeds caused serious problem on yield reduction of basmati rice worldwide. Losses caused by weeds varied from one country to another, depending on the presence of dominant weeds and the control methods practiced by farmers; therefore, suitable plant population and weed management practices should be adopted. Keeping these in mind, a field experiment was carried out during kharif seasons of 2009 and 2010 at crop Research Centre of SVPUA&T, Meerut, India comprising 4 planting geometries, viz. 20, 30, 40, and 50 hills m?2 as main plot factor, and 5 weed management practices (Butachlor @ 1.0 kg ha?1, Butachlor @ 1.0 kg ha?1 fb (followed by) one hand weeding, Butachlor @ 1.0 kg ha?1 fb Almix @ 4 g ha?1, two hand weedings and weedy check) in a split plot design with 3 replications. Experimental results revealed that plant population of 50 hills m?2 proved superior over that of 20 hills m?2 in respect of weed density, weed dry weight, number of tillers m?2, yield attributes, grain, straw, and biological yields. The maximum grain yield (29.00 and 31.00 q ha?1) and straw yield (51.30 and 52.50 q ha?1) were recorded in 50 hills m?2 followed by 40 hills m?2 during 2009 and 2010, respectively. In respect of nitrogen, phosphorus, and potassium removal, a reverse trend was observed: the highest in 20 hills m?2 followed by 30, 40, and 50 hills m?2. As far as the weed management practices are concerned, both chemical and mechanical methods of weed control were found superior over weedy check. The lowest weed density, dry weight, and highest weed control efficiency, maximum length of panicle?1, number of panicle (m2), and 1000-grain weight and grain yield of 30.40 and 32.60 q ha?1 were recorded with two hand weedings which was at par with Butachlor @ 1.0 kg ha?1 fb one hand weeding over rest of the weed management practices. 相似文献
3.
Rumesh Ranjan Ashish Kumar Swarupa Nanda Mandal 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(7):588-595
ABSTRACT Nitrogen uptake being part of nitrogen use efficiency (NUE) is largely decided by root traits. Root traits variability has hardly been explored by breeders mainly because of difficulties in scoring. The hydroponic system requiring lesser space for precise phenotyping of large numbers of genotypes independently of the growing season can be a suitable alternative. However, the effectiveness of hydroponic screening methods needs to be verified under the soil condition of the field or pot. In the present study, root traits and NUE were investigated in 19 genotypes under two conditions (hydroponic and pipe filled with soil). Both environments revealed large variability for root traits and NUE under high and low N conditions establishing the absence of any direct selection for these traits in the past. Under both sets of experimentation, NUpE was largely responsible for improved nitrogen efficiency mainly because of higher root biomass. The significant association between the two screening methods i.e. hydroponic and pot filled with soil under both low and high N condition support large scale screening for root traits under hydroponic condition. 相似文献
4.
Rishi Raj Anil Kumar I. S. Solanki Shiva Dhar Anchal Dass Ashish Kumar Gupta Vikash Kumar C. B. Singh R. K. Jat U. C. Pandey 《Paddy and Water Environment》2017,15(4):861-877
A field study on assessment of crop establishment methods on yield, economics and water productivity of rice cultivars under upland and lowland production ecologies was conducted during wet seasons (June–November) of 2012 and 2013 in Eastern Indo-Gangetic Plains of India. The experiment was laid-out in a split-plot design (SPD) and replicated four times. The main-plot treatments included three crop establishment methods, viz. dry direct-seeded rice (DSR), system of rice intensification (SRI) and puddled transplanted rice (PTR). In sub-plots, five rice cultivars of different groups like aromatic (Improved Pusa Basmati 1 and Pusa Sugandh 5), inbreds (PNR 381 and Pusa 834) and hybrid (Arize 6444) were taken for their evaluations. These two sets of treatments were laid-out simultaneously in two production ecologies, upland and lowland during both years. In general, lowland ecology was found favourable for rice growth and yield and resulted in 13.2% higher grain yield as compared to upland ecology. Rice grown with SRI method produced 19.4 and 7.0% higher grain yield in 2012 and 20.6 and 7.1% higher in 2013, over DSR and PTR. However, PTR yielded 13.1 and 14.5% higher grain over DSR during 2012 and 2013, respectively. On an average, Arize 6444 produced 26.4, 26.9, 28.9 and 54.7% higher grain yield as compared to PS 5, P 834, PNR 381 and IPB1, respectively. Further, the interaction of production ecologies × crop establishment methods revealed that, in upland ecology, SRI recorded significantly higher grain yield as compared to PTR and DSR, but in lowland, grain yield resulting from SRI was similar to the yield obtained with PTR and significantly higher than DSR. The latter two methods (PTR and DSR) yielded alike in lowland ecology in both study years. The production ecologies × crop establishment methods × cultivars interaction on grain yield showed that the growing of Arize 6444 cultivar using SRI method in upland ecology resulted in the higher grain yield (8.87 t/ha). But the cost of production was also highest in SRI followed by PTR and DSR across production ecologies and cultivars. Cultivation of hybrid (Arize 6444) involved higher cost of production than all other cultivars. Irrespective of crop establishment methods and cultivars, gross returns, net returns and B:C ratio were significantly higher in lowland compared to upland ecology. Owing to higher grain yield, SRI method fetched significantly higher gross returns and net returns over PTR and DSR. Average increase in net return with Arize 6444 was 68.8, 41.0, 37.7 and 33.1% over IPB 1, PNR 381, P 834 and PS 5, respectively. There was a saving of 30.7% water in SRI and 19.9% in DSR over PTR under upland ecology. Similarly in lowland ecology, water saving of 30.2% was observed in SRI and 21.2% in DSR over PTR. Due to higher yield and saving on water, SRI returned significantly higher total water productivity (TWP) (5.9 kg/ha-mm) as compared to DSR (3.5 kg/ha-mm) and PTR (3.6 kg/ha-mm) under upland ecology. In lowland ecology, also SRI (6.2 kg/ha-mm) resulted in higher TWP as compared to other two methods. However, DSR gave significantly higher TWP as compared to PTR. Among cultivars, hybrid Arize 6444 recorded the highest TWP in both upland and lowland production ecologies across crop establishment methods. Hence, growing of hybrid Arize 6444 with SRI method can enhance rice productivity and water-use efficiency in lowland and upland production ecologies of Eastern Indo-Gangetic Plains and in other similar regions. 相似文献
5.
Santosh Kumar Subodh Kumar Vijay Kumar Kaushal K. Singh Birendra K. Roy 《Veterinary research communications》2009,33(8):887-893
The present experiment was designed to study the pharmacokinetics of levofloxacin in six healthy cross bred female cow calves (4 to 6 months age) weighing between 40 to 80 kg. Plasma from blood was separated by centrifugation at 10,000 rpm. Quantitative estimation of levofloxacin was done by UV-VIS spectrophotometer at 286 nm. The mean maximum plasma concentration (Cpmax ) of levofloxacin in febrile calves (5.28?±?0.32 µg/ml) did not differ significantly as compared with healthy calves (4.50?±?0.22 µg/ml) after single dose (20 mg/kg) oral administration. The mean therapeutic plasma concentration ( Cpther ) of levofloxacin was maintained for longer period in febrile calves (10 h) as compared to healthy calves ( 8 h). The mean maximum urine concentration (Cumax) in febrile (40.86?±?2.19 µg/ml) also did not differ significantly as compared with healthy calves (39.38?±?2.43 µg/ml). No significant difference in various pharmacokinetic parameters of plasma was observed in healthy calves ( β?=?0.23?±?0.01/h ; t1/2 β?=?3.00?±?0.17 h and MRT?=?4.66?±?0.14 h ) and febrile calves ( β?=?0.23?±?0.01/ h; t1/2 β?=?3.05?±?0.16 h and MRT?=?5.04?±?0.14 h ) . The mean value of β, and t ½ β calculated in urine also did not differ between healthy and febrile calves. However, the value of MRT(3.79?±?0.07 h) and ClB(1.65?±?0.09 ml/kg/min) calculated in urine of febrile calves significantly(p?0.05) differ to healthy calves(MRT?=?3.15?±?0.03 h;ClB?=?2.09?±?0.13 ml/kg/min). Based on kinetic profile levofloxacin may be given orally at the dose rate of 1.49 mg/kg B.W.at 8 h intervals in febrile calves. 相似文献
6.
Exploring genetic diversity for heat tolerance among lentil (Lens culinaris Medik.) genotypes of variant habitats by simple sequence repeat markers 下载免费PDF全文
Dharmendra Singh Chandan K. Singh Ram Sevak S. Tomar Ashish K. Chaturvedi Divya Shah Arun Kumar Madan Pal 《Plant Breeding》2016,135(2):215-223
The study was carried out to assess genetic diversity among 119 lentil genotypes grown in different habitats for heat tolerance using morpho‐physiological and reproductive traits and SSR markers. High‐temperature stress was applied at seedling (35/33°C) and anthesis stages (35/20°C) to study the effects on morpho‐physiological and reproductive traits under hydroponic condition, which was compared with non‐stressed and stressed field conditions. A set of 209 alleles were identified by 35 SSR markers among the genotypes. Genetic diversity and polymorphism information content values varied between 0.0494–0.859 and 0.0488–0.844, with mean values of 0.606 and 0.563, respectively. Genotypes were clustered into nine groups based on SSR markers. Morpho‐physiological and reproductive traits under heat stress were found to be significantly different among SSR clusters. These findings suggest that heat adaptation is variable among the genotypes and the tolerant materials can be evolved through hybridization using parents from different clusters with diverse mechanisms of heat tolerance. 相似文献
7.
S. Gupta R. Kaushal R. S. Spehia S. S. Pathania V. Sharma 《Journal of plant nutrition》2017,40(7):921-927
Inorganic fertilizers alone cannot sustain high levels of productivity. This study was conducted to determine whether higher productivity of capsicum could be achieved by conjoint application of chemical fertilizers and plant growth promoting rhizobacteria (PGPR). Four PGPR isolates (RS2, RS3, RS4, and RS7) from capsicum roots and rhizosphere were evaluated at Solan, Himachal Pradesh (India), during 2009–2012. Two best performers: RS2 and RS7 were tried singly or in consortium with different levels of chemical fertilizers under field conditions, Randomized Block Design, replicated thrice. The conjoint use of 100% recommended nitrogen, phosphorus, and potassium (NPK) doses through chemical fertilizers (RDF) plus PGPR significantly increased fruit yield, plant height, and biomass by 37%, 20%, and 30%, respectively, over sole application of 100% RDF (control). Further, response of capsicum to 80% RDF plus PGPR was statistically comparable with control. The results, therefore, indicate the potential of isolated PGPR strains to substitute about 20% NP fertilizers besides enhanced productivity of capsicum. 相似文献
8.
Sandeep?KumarEmail author Ranjith?P.?Udawatta Stephen?H.?Anderson Ashish?Mudgal 《Agroforestry Systems》2011,83(1):51-62
Buffers have been found to reduce non-point source pollution (NPSP) from watersheds. Hydrologic simulation models assist in
predicting the effects of buffers on runoff and sediment losses from small watersheds. The objective of this study was to
calibrate, validate and simulate runoff and sediment losses and compare buffer effects on NPSP losses relative to control
watersheds (no buffer) for seven years. The experimental design consists of four watersheds under pasture management which
were monitored from 2002 through 2008; two with agroforestry buffers (AgB 100 and AgB 300) and two control watersheds (CW
400 and CW 600). Pasture areas included red clover (Trifolium pretense L.) and lespedeza (Kummerowia stipulacea Maxim.) planted into fescue (Festuca arundinacea Schreb.) while the agroforestry buffer area included Eastern cottonwood trees (Populus deltoids Bortr. ex Marsh.) planted into fescue. The APEX model was calibrated from 2002 to 2005 and was validated from 2006 to 2008.
The r
2
and NSE values for the calibration and validation periods of the runoff varied from 0.52 to 0.78 and 0.50 to 0.74, respectively.
The model did not predict sediment loss very well probably due to insufficient number of measured events and low measured
sediment loss. The measured runoff was 57% higher for CW watersheds compared to AgB watersheds. The measured sediment loss
was 95% higher for CW watersheds compared to AgB watersheds. After calibrating and validating the model, it was run for long-term
scenario analyses for 10 years from 1999 to 2008. Simulated buffer width had a significant influence on runoff. Simulated
runoff decreased by 24% when the buffer width was doubled compared to losses associated with the measured buffer width. Simulated
runoff from the CW watersheds was 11% higher with double stocking density (relative to measured density) compared to AgB watersheds
with double stocking density. With half stocking density (relative to measured density), the AgB watershed had 18% lower runoff
compared to CW. Results from this study imply that establishment of agroforestry buffers on grazed pasture watersheds reduce
runoff and sediment losses compared to control watersheds without buffers. 相似文献
9.
We studied variations in tree biomass and carbon sequestration rates of Chir Pine(Pinus roxburghii. Sarg.) forest in three categories of forest disturbance, protected, moderately disturbed, and highly disturbed. In the first year, total biomass was 14.7 t?ha-1 in highly disturbed site, 94.46 t?ha-1 in moderately disturbed forest, and 112.0 t?ha-1 in protected forest. The soil organic carbon in the top 20 cm of soil ranged from 0.63 to 1.2%. The total rate of carbon sequestration was 0.60(t/ha)·a-1on the highly disturbed site, 1.03(t/ha)·a-1 on the moderately disturbed site, and 4.3(t/ha)·a-1 on the protected site. 相似文献
10.
Kripal Singh Ashish Kumar Mishra Bajrang Singh Rana P. Singh Dharani Dhar Patra 《Land Degradation \u0026amp; Development》2016,27(2):223-230
Tillage modifies soil structure and has been suggested as a practice to improve physical, hydrological and chemical properties of compacted soils. But little is known about effect of long‐term tillage on physicochemical soil properties and crop yield on sodic soils in India. Our objective was to investigate the effect of different tillage regimes on crop yield (wheat and paddy rice) and physicochemical properties of sodic soils. Two sodic sites under conventional tillage for 5 (5‐YT; 5‐year tillage) and 9 (9‐YT; 9‐year tillage) years were selected for this study. Changes in crop yield and physicochemical soil properties were compared with a control, sodic land without any till history, that is, 0‐year tillage/untilled (0‐YT). Five replicated samples at 0‐ to 10‐cm and 10‐ to 20‐cm soils depths were analysed from each site. In the top, 0‐ to 10‐cm soil depth 5‐YT and 9‐YT sites had higher particle density (Pd), porosity, water holding capacity, hydraulic conductivity, organic carbon, total nitrogen (Nt), available nitrogen (Navail), phosphorus (Pavail) and exchangeable calcium (Exch. Ca++) than 0‐YT, whereas bulk density (Bd), C : N ratio and CaCO3 were significantly lower. Bd, pH, EC and CaCO3 increased significantly with depth in all the lands, whereas Pd, porosity, water holding capacity, hydraulic conductivity, organic carbon, Nt, Navail, Pavail and Exch. Ca++ decreased. We conclude that continuous tillage and cropping can be useful for physical and chemical restoration of sodic soils. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献