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151.
Smita JainRafat S. Ahmed Vinod Kumar AroraBasu Dev Banerjee 《Pesticide biochemistry and physiology》2011,100(2):182-186
Triazophos, O,O-diethyl-1-H-1,2,4-triazol-3-yl phosphorothioate, (TZ) is an organophosphorus pesticide which is extensively used in agriculture for controlling insect pests. Except a FAO/WHO report no study has investigated its short-term toxicity with respect to its potential to cause biochemical and histopathological alterations. The present study was designed to identify the effect of TZ at different doses (1.64, 3.2 and 8.2 mg/kg) on the oxidative stress parameters in blood as well as organs involved in xenobiotic metabolism (liver and brain) following chronic exposure for 90 days. Moreover, the study also delineates the effect of TZ on the histo-architecture of these organs. The results indicated a dose dependent induction (p < 0.001) of oxidative stress, as evident by increased malondialdehyde (MDA) level and compromised antioxidant defense including glutathione S transferase (GST) activity, glutathione (GSH) content and ferric reducing ability of plasma (FRAP) in blood, and increased MDA level with concomitantly decreased GSH content in tissues, following chronic exposure to TZ. The ratio of MDA: FRAP in blood was found to be increased following chronic exposure to TZ and may serve as a suitable indicator of severity of oxidative damage. Onset of such biochemical alterations is one of the early adaptive responses to TZ exposure which leads to histopathological alterations in terms of diffuse fatty changes expanding from mid-zonal area to whole lobule in liver. However, increased oxidative stress did not bring any morphological alteration in brain. The present study concludes that induction of oxidative stress, leading to subsequent histopathological alterations in liver, is an important mechanism underlying the TZ induced chronic toxicity. 相似文献
152.
Penultimate and last instar larvae of the common citrus swallowtail butterfly, Papilio demoleus L. (Papilionidae: Lepidoptera), were treated with different doses of a novel juvenoid, diofenolan. Several deformities were
observed as a result of topical administration of diofenolan which include delay in larval–larval and larval–pupal ecdysis,
ecdysial failure, mortality, severe reduction in pupation, deformed pupae and complete inhibition of adult emergence. The
juvenoid diofenolan severely hampers the normal growth, development and metamorphosis of P. demoleus and can be incorporated into integrated pest management programs for successful control of this important pest of citrus
all over the world. 相似文献
153.
Entomophaga aulicae (Hoffman in Bail) Batko (Zygomycotina: Entomophthorales) was found to cause epizootics in Spilarctia obliqua (Walker) (Arctiidae: Lepidoptera), a polyphagous pest in Manipur, India. Infected caterpillars climbed to elevated positions
on plants where they hung upside down, attached by their abdominal prolegs. Infection levels reached up to 57%. The conidiophores
are simple, conidia are ovoid to pyriform in shape, and the nuclei stained readily in aceto-orcein. Secondary, tertiary conidia
and resting spores were also observed. No rhizoids and cystidia were found. This is the first report of E. aulicae infecting S. obliqua in Manipur. 相似文献
154.
Manoj Kumar Solanki Nidhi Singh Rajesh Kumar Singh Pratiksha Singh Alok K. Srivastava Sudheer Kumar Prem L. Kashyap Dilip K. Arora 《Phytoparasitica》2011,39(5):471-481
Tomato root rot caused by Rhizoctonia solani is a major soilborne disease resulting in significant yield loss. The culture filtrates of six isolates of Trichoderma/Hypocrea species were evaluated for in vitro production of hydrolytic enzymes. Results demonstrated that all the six isolates were able to produce chitinase, β-1, 3 glucanase
and protease in the range of 76–235 μmol GlcNAc min-1 mg-1 protein, 31.90–37.72 nmol glucose min-1 mg-1 proteins and 63.05–86.22 μmol min-1 mg-1 proteins, respectively. Trichoderma/Hypocrea-based formulation(s) were prepared with chitin (1% v:v) and CMC (0.5% w:v) for root rot management in a greenhouse. Root dip
application with bioformulation(s) resulted in a significant reduction of the root rot index. In addition, bioformulations
increased plant growth attributing traits significantly relative to untreated control. Accumulation of total phenols, peroxidase,
polyphenoloxidase and phenylalanine ammonia lyase increased in chitin-supplemented Trichoderma/Hypocrea formulation-treated plants challenged with R. solani. The results suggest that chitin-fortified bioformulation(s) could be an effective system to control root rot of tomato in
an eco-compatible manner. 相似文献
155.
Soil infiltration, runoff and sediment yield from a shallow soil with varied stone cover and intensity of rain 总被引:6,自引:0,他引:6
Uttam Kumar Mandal K. V. Rao P. K. Mishra K. P. R. Vittal K. L. Sharma B. Narsimlu & K. Venkanna 《European Journal of Soil Science》2005,56(4):435-443
Stones on the surface of the soil enhance infiltration and protect the soil against erosion. They are often removed in modern mechanized agriculture, with unfortunate side‐effects. We evaluated experimentally the influence of surface stones on infiltration, runoff and erosion under field conditions using a portable rainfall simulator on bare natural soil in semi‐arid tropical India, because modernization and mechanization often lead to removal of these stones in this region. Four fields with varied cover of stones from 3 to 65% were exposed to three rainfall intensities (48.5, 89.2 and 136.8 mm hour?1). Surface stones retarded surface runoff, increased final infiltration rates, and diminished sediment concentration and soil loss. The final infiltration ranged from 26 to 83% of rainfall when the rainfall intensity was 136.8 mm hour?1. The reduction in runoff and soil erosion and increase in infiltration were more pronounced where stones rested on the soil surface than where they were buried in the surface layer. The sediment yield increased from 2 g l?1 for 64.7% stone cover with rainfall of 48.5 mm hour?1 to 70 g l?1 for 3.5% stone cover with rain falling at 136.8 mm hour?1. The soil loss rate was less than 2 t ha?1 hour?1 for the field with stone cover of 64.7% even when the rainfall intensity was increased to 136.8 mm hour?1. The effects of stones on soil loss under the varied rainfall intensities were expressed mathematically. The particles in the sediment that ran off were mostly of silt size. 相似文献
156.
L. T. Khemani G. A. Momin Medha S. Naik R. Kumar Bh. V. Ramana Murty 《Water, air, and soil pollution》1985,24(2):131-140
Surface measurements of Aitken nuclei have been made at a few representative environments in India. The periods of measurements have ranged from a few days to a few years depending upon the place of measurement. Aircraft measurements of Aitken nuclei were made at one of the locations during three successive monsoon periods. During part of the time simultaneous measurements were made of the trace gases SO2, NH3, NO2, and O3. The study presents the seasonal and diurnal variation of Aitken nuclei in the different environments and their association with the trace gas concentrations. 相似文献
157.
We investigated C management index (CMI; an indicator of sustainability of a management system and is based on total and labile
C) and soil aggregation in medium-textured soils (silt loam and silty clay loam) under different cropping systems as follows:
maize-wheat (M-W), rice-wheat (R-W), soybean-wheat (S-W), Guinea grass, and Setaria grass. Field experiments were 6–32 years
long and were located in the wet-temperate zone of northwest Himalayas. The plant nutrients were applied through chemical
fertilizers (urea, superphosphate, and muriate of potash) with or without organic materials (FYM, wheat straw, and Lantana spp.). The content of total C (CT), labile C (CL), CMI, mean weight diameter (MWD), and aggregate porosity varied significantly under different cropping systems. The range
was 1.59 (R-W)–4.29% (Setaria) for CT, 1.23 (R-W)–3.89 mg/kg (Guinea grass) for CL, 52.09 (R-W)–129.77 (Guinea grass) for CMI, 0.90 (R-W)–5.09 (Guinea grass) for MWD, and 41.5 (R-W)–56.8% (S-W) for aggregate
porosity. Aggregate porosity was highest (56.8%) under S-W, followed by grasses (50.1–51.2%), and M/R-W (41.5–50.0%). As per
these data, (a) continuous use of N alone as urea lowered soil sustainability over control (no fertilizers); (b) use of NPK
at recommended rates improved soil productivity over control; (c) the NPK + organic amendments further improved soil sustainability;
and (d) the sustainability under different cropping systems followed the order: perennial grasses > soybean-wheat > maize-wheat
> rice-wheat. 相似文献
158.
A study was carried out on a silty clay loam soil (Typic Haplustept) to evaluate the effect of farmyard manure (FYM) vis‐à‐vis fertilizer and irrigation application on the soil organic C content and soil structure. The fertilizer treatments comprised of eight different combinations of N and FYM and three water regimes. The results indicated that the application of FYM and increasing N rate increased soil organic carbon (SOC) content. Addition of FYM also increased the percentage of large sized water stable aggregates (> 5 mm) and reduced the percentage of smaller size aggregates. This was reflected in an increase in the mean weight diameter (MWD) and improved soil structure. The organic carbon content in macroaggregates (> 1 mm) was greater compared to microaggregates, and it declined with decrease in size of microaggregates. This difference in organic C content between macro‐ and microaggregates was more with higher N dose and FYM treated plots. The effect of residual FYM on MWD and organic C content of the soil after wheat harvest was not significant. The effect was less in deeper layers compared to surface layers of the soil. MWD was significantly correlated with the SOC content for the top two layers. 相似文献
159.
G. V. Subbarao C. Johansen J. V. D. K. Kumar Rao M. K. Jana 《Biology and Fertility of Soils》1990,9(1):49-53
Summary There were significant differences among pigeonpea [Cajanus cajan (L.) Millsp] Rhizobium sp. strains (IC 3506, IC 3484, IC 3195, and IC 3087) in their ability to nodulate and fix N2 under saline conditions. Pigeonpea plants inoculated with IC 3087 and IC 3506 were less affected in growth by salinity levels of 6 and 8 dS m-1 than plants inoculated with the other strains. For IC 3506, IC 3484, and IC 3195, there was a decrease in the number of nodules with increasing salinity, while the average nodule dry weight and the specific nitrogenase activity remained unaffected. However, in IC 3087, the number of nodules increased slightly with increasing salinity. Leaf-P concentrations increased with salinity in the inoculated plants irrespective of the Rhizobium sp. strain, and leaf-N concentrations decreased with increasing salinity in IC 3484 and IC 3195 only. Shoot-Na and-Cl levels were further increased in these salt-sensitive strains only at 8 dS m-1. Therefore there may be scope for selecting pigeonpea Rhizobium sp. symbioses better adapted to saline conditions. The Rhizobium sp. strains best able to form effective symbioses at high salinity levels are not necessarily derived from saline soils.Submitted as JA No. 919 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) 相似文献
160.
Paramashivappa R Kumar PP Vithayathil PJ Rao AS 《Journal of agricultural and food chemistry》2001,49(5):2548-2551
Commercially available cashew (Anacardium occidentale L.) nut shell liquid (CNSL) mainly contains the phenolic constituents anacardic acid, cardol, and cardanol. These phenolic constituents are themselves heterogeneous, and each of them contains saturated, monoene, diene, and trienes in the fifteen-carbon side chain. This communication describes the separation of anacardic acid, cardol, and cardanol for industrial application. Anacardic acid was selectively isolated as calcium anacardate. The acid-free CNSL was treated with liquor ammonia and extracted with hexane/ethyl acetate (98:2) to separate the mono phenolic component, cardanol. Subsequently, ammonia solution was extracted with ethyl acetate/hexane (80:20) to obtain cardol. 相似文献