Compaction of sandy soils for irrigation management     

R. P. Agrawal  B. S. Jhorar  J. S. Dhankar  M. Raj 《Irrigation Science》1987,8(4):227-232

Summary Several irrigation management experiments were conducted at different locations on sandy soils in Haryana State to overcome excessive permeability, poor soil moisture retention and storage in the root zone. Subsurface compaction to 30–40 cm depth created by 6 passes of a 1,500 kg tractor-driven iron roller, 24 to 48 h after irrigation, was found to be beneficial in reducing irrigation requirement. In general, yield of different crops was not affected significantly by surface rolling, except that of mustard which increased significantly. Slight increase in subsurface compaction, about 0.1 g cm^–3, increased the soil moisture retention and reduced the infiltration rate and saturated hydraulic conductivity. Hydraulic conductivity was a better parameter than bulk density for evaluating the effect of rolling. The depth of irrigation water applied in rolling treatment was about 58–74% that of the no-rolling control. Compaction thus reduced water input to these sandy soils without adversely affecting the crop yield.  相似文献   

Influence of soil inoculation with vesicular-arbuscular mycorrhiza and a phosphate-dissolving bacterium on plant growth and ³²P-uptake     

J. Raj  D.J. Bagyaraj  A. Manjunath 《Soil biology & biochemistry》1981,13(2):105-108

The influence of inoculation of soil with a vesicular-arbuscular mycorrhizal fungus (Glomus fasciculatus) and a phosphate-dissolving bacterium (Bacillus circulans) on phosphate solubilization, growth of finger millet (Eleusine coracana) and phosphorus uptake from ³²P-labelled tricalcium phosphate and superphosphate were studied. The mycorrhizal plants produced more dry matter and removed more ³²P from the soil than non-mycorrhizal plants, but did not show increased ³²P activity per unit plant mass. The 30 mm NH₄F-HCl extractable ³²P (available ³²P) in soil, plant ³²P activity and total P uptake were enhanced by soil inoculation with the bacterium. In the treatment receiving both inocula a synergistic effect was recorded with increased P uptake and dry matter production.  相似文献   

Acidification of Surface Water in Central India     

Shankar G. Aggarwal  Chandra K. Chandrawanshi  Raj M. Patel  Smita Agarwal  Anand Kamavisdar  Girdhar L. Mundhara 《Water, air, and soil pollution》2001,130(1-4):855-862

The results of the seasonal analysis of the chemistry of rain, fog and surface water of central India for the two years: June 1996 to May 1998 are presented. A total of 636 rain water samples, 146 fog water samples and 226 surface water samples of 8 locations: namely, Ambikapur, Baikunthpur, Korba, Bilaspur, Raipur, Bhilai, Dallirajhara and Kanker, from different sites were collected for the present study. This paper documents the occurrence of acidic rain and fog events and their effect on surface water pH and aquatic life in central India. Most of the rain and fog water samples collected from Baikunthpur and Korba sites were found to be acidic in nature (i.e. pH < 5). The volume weighted mean pH of rain and fog water samples of these sites was 4.8 and 4.4 with lowest pH 4.4 and 4.0, respectively. However, samples from Ambikapur, Bilaspur, Raipur and Bhilai were slightly acidic and their pH values were always around 5.8. One reservoir (mean pH 5.8) and two stop dams (mean pH 4.4 and 4.2) in Baikunthpur area were found to be acidic. The effect of acidification of water on metal-accumulation in muscles of fishes was studied. Concentrations of Al, Hg, Mn, Cd and Pb were higher in fish from acid, than from less acid waters. Causes of acidification of the atmospheric water and surface water are critically discussed.  相似文献   

Preventive effect of sialylglycopeptide-nondigestive polysaccharide conjugates on salmonella infection     

Sugita-Konishi Y  Kobayashi K  Sakanaka S  Juneja LR  Amano F 《Journal of agricultural and food chemistry》2004,52(17):5443-5448

We have previously reported that sialylglycopeptide (SGP) and its derivatives isolated from egg yolk had a preventive effect on Salmonella infection in vivo; however, their retention time in the gut was rather short. To improve on this, SGP was conjugated with carboxymethyl cellulose (CMC) or carboxymethyl dextran (CMD). The conjugates inhibited the binding of Salmonella enteritidis and Escherichia coli to Caco-2 cells. Infection experiments with mice revealed that the SGP-CMD conjugate (SGP-CMD) had a strong protective effect against Salmonella infection. A turnover experiment in mice administered with radiolabeled SGP-CMD showed that SGP-CMD was more slowly absorbed into the blood and thus remained longer in the intestinal tract than SGP. SGP-CMD itself did not influence the production of tumor necrosis factor alpha (TNF-alpha), interleukin-1 beta, or nitrite ion (NO(2)(-)) by macrophages, although it suppressed that of TNF-alpha and NO(2)(-) in zymosan-treated macrophages, suggesting no causative effects of inflammation in SGP-CMD. SGP-CMD is potentially useful as a food ingredient with a preventive effect on Salmonella infection.  相似文献   

黑龙港流域夏玉米生育期降水、需水和干旱时空分布特征     

魏钟博  边大红  杜雄  Pushpa Raj  崔彦宏 《农业工程学报》2020,36(9):124-133

黑龙港流域地下水超采导致水分极度匮乏,提高降水利用效率成为该区夏玉米生产的关键。该文利用黑龙港流域18个地面气象观测站1966—2015年逐日气象数据,对玉米全生育期及各生育阶段的有效降水量、需水量、作物水分亏缺指数、干旱发生频率的时空分布特征等进行了分析。结果表明,夏玉米全生育期有效降水量292.89～361.56 mm,呈"东北高、西南低"的趋势;需水量362.82～444.04 mm,呈"南部高,北部低"的趋势;近50年总有效降水量和需水量均呈下降趋势,且需水量的变化与平均日照时数、平均风速呈高度正相关;全区干旱发生频率为48.30%,其中南部超33.3%,中部及北部超66.6%;黑龙港中部和北部在成粒和灌浆阶段出现干旱的几率较大,南部在成粒阶段出现干旱的几率较大。该研究为黑龙港夏玉米降水资源的高效利用提供了理论依据。  相似文献   

The effects of electrolyte concentrations on calcium-sodium exchange equilibria in two soil samples of india     

S.R. Poonia  S.C. Mehta  Raj Pal 《Geoderma》1984,32(1):63-70

The effects of total electrolyte concentrations of the equilibrium solutions (t.e.c.) on Ca²⁺-Na⁺ exchange equilibria in two soil samples (high and low in organic matter, clay content and CEC) were studied. Homoionic (Na⁺-saturated) soil samples were equilibrated with solutions having a large range in sodium adsorption ratio (SAR) at 25, 50, 75 and 100 meq. 1^-1 t.e.c. The exchange equilibria data were analysed, using a thermodynamic approach and the selectivity coefficients of Gapon (1933), Vanselow (1932) and Krishnamoorthy et al. (1948) (K_G, K_V and K_KDO). At a given proportion of Ca²⁺: Na⁺ in the equilibrium solution, the development of the exchangeable sodium percentage (ESP) in both soil samples increased with the increase in t.e.c. At a given SAR, the effect of t.e.c. on the development of ESP was less on a soil sample with high organic matter (O.M.), clay content and cation exchange capacity (CEC) than on a soil sample with low O.M., clay content and CEC. The values of exchange selectivity coefficients decreased with the increase in t.e.c, and did not remain constant throughout the exchange isotherm for any of the t.e.c. tried.  相似文献   

Components of resistance to late leaf spot and rust among interspecific derivatives and their significance in a foliar disease resistance breeding in groundnut (Arachis hypogaea L.)     

Sangam Lal Dwivedi  Suresh Pande  Joginedi Narayan Rao  Shyam Narayan Nigam 《Euphytica》2002,125(1):81-88

Late leaf spot (LLS) and rust cause substantial yield losses and reduce the fodder and seed quality in groundnut (Arachis hypogaea L.). Adoption of resistant cultivars by the semi-arid tropic farmers is the best option to overcome yield losses. Knowledge on components of resistance to these diseases should facilitate the development of groundnut cultivars with enhanced resistance to LLS and rust. The objectives of the experiments were to study the genetic variability and relationships among components of resistance to LLS and rust, and assess their significance in disease resistance breeding. Fifteen interspecific derivatives for LLS and 14 for rust and a susceptible control, TMV 2, were evaluated in a randomised complete block design with two or three replications under greenhouse conditions. The experiments were repeated twice. Genotypic differences were highly significant for all the traits studied. Resistance to LLS is due to longer incubation and latent periods, lesser lesions per leaf, smaller lesion diameter, lower sporulation index, and lesser leaf area damage and disease score. Selection based on components of resistance to LLS may not lead to plants with higher retained green leaf area. The remaining green leaf area on the plant should, therefore, be the major selection criteria for resistance to LLS in breeding programs. Resistance to rust is due to longer incubation and latent periods, fewer pustules per leaf, smaller pustule diameter, lower sporulation index, and lesser leaf area damage and disease score. Rust resistant components appear to work additively, therefore, selection based on resistance components together with green leaf area retained on the plant should be the basis of selecting for resistance to rust in breeding programs. ICGV 99005, 99003, 99012, and 99015 for rust and ICGV 99006, 99013, 99004, 99003, and 99001 for LLS are the better parents for use in resistance breeding programs. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Effect of combinations of morphine,dexmedetomidine and maropitant on the electroencephalogram in response to acute electrical stimulation in anaesthetized dogs     

Sandeep Raj Karna  Paul Chambers  Craig B. Johnson  Preet Singh  Lauren A. Stewart  Nicolas Lopez-Villalobos  Kavitha Kongara 《Journal of veterinary pharmacology and therapeutics》2020,43(6):538-546

This study was conducted to compare the efficacy of combinations of morphine, dexmedetomidine and maropitant in preventing the changes in electroencephalographic (EEG) indices of nociception in anaesthetized dogs subjected to a noxious electrical stimulus. In a crossover study, eight healthy adult dogs were randomly allocated to four groups: Mor: morphine 0.6 mg/kg; Dex + Mor: morphine 0.3 mg/kg + dexmedetomidine 5 μg/kg; Maro + Mor: morphine 0.3 mg/kg + maropitant 1 mg/kg; and Dex + Maro + Mor: morphine 0.2 mg/kg + dexmedetomidine 3 μg/kg + maropitant 0.7 mg/kg. Following intramuscular administration of test drugs in a minimal anaesthesia model, a supramaximal electrical stimulus (50 V at 50 Hz for 2 s) was applied and the EEG data were recorded. There were significant increases (p < .05) in the poststimulus median frequency (F50) only in groups Mor and Maro + Mor. Dex + Mor group had a significantly lower change in F50 and F95 compared to all other treatment groups. There was no correlation of the changes in EEG frequencies with blood plasma concentration of the drugs during and after noxious stimulation. Combination of dexmedetomidine and morphine was most effective in abolishing the changes in EEG indices in response to a noxious stimulus indicating a supra-additive interaction between these two drugs.  相似文献   

Molecular identification of a new isolate of <Emphasis Type="Italic">Cucumber mosaic virus</Emphasis> subgroup II from basil (<Emphasis Type="Italic">Ocimum sanctum</Emphasis>) in India     

A. A. Khan  R. Sharma  B. Afreen  Q. A. Naqvi  S. Kumar  S. K. Snehi  S. K. Raj 《Phytoparasitica》2011,39(2):199-203

Natural occurrence of mosaic disease was observed on basil (Ocimum sanctum L.) in Aligarh, U. P., India, during 2008. The disease could be transmitted by sap inoculations from naturally infected O. sanctum to O. sanctum and some test plant species. Cucumber mosaic virus (CMV) was detected by RT-PCR using coat protein gene specific primers of CMV (Acc. AM180922 & AM180923), which resulted in the expected size ~650 bp amplicon in infected samples. The amplicon was cloned, sequenced and data were deposited in GenBank Acc. EU600216. The sequence data analysis revealed 97–99% identities at both nucleotide and amino acid levels with the CMV strains of subgroup II reported worldwide. Based on the high sequence identities and close phylogenetic relationships with CMV subgroup II strains, the virus under study has been identified as a new isolate of CMV subgroup II and designated as CMV-Basil.  相似文献   

Molecular identification of an Ageratum enation virus isolate associated with mosaic disease of pointed gourd (Trichosanthes dioica) in India     

S. K. Raj  S. K. Snehi  M. S. Khan  A. K. Tiwari  G. P. Rao 《Phytoparasitica》2011,39(5):497-502

A severe mosaic disease of pointed gourd (Trichosanthes dioica Roxb.) was observed with significant disease incidence in Gopalganj, India, during 2008. Begomovirus was detected from symptomatic leaf samples by polymerase chain reaction (PCR) using coat protein gene-specific primers of a well characterized begomovirus which revealed positive amplification of expected size ~800 bp DNA band. To confirm begomovirus association, the complete DNA-A was amplified using three sets of begomovirus DNA-A primers. The amplicons were cloned, sequenced, and sequence of the complete DNA-A (2757 nt) was determined by combining the sequence data of all amplicons (Accession no. GQ268327). The sequence data showed 99–93% sequence identities and close phylogenetic relationships with isolates of Ageratum enation virus (AgEV). The begomovirus associated with mosaic disease of T. dioica was identified as an isolate of Ageratum enation virus, which is a new record from India.  相似文献