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101.
Vegetation strips (VS) along with conservation tillage, application of organic amendments and weed mulching improve crop yields by reducing run‐off and topsoil erosion. To investigate these issues, an experiment was conducted under rainfed conditions using grass VS for four and a half years (June 2007 to October 2011) at Dehradun, Uttarakhand, in the Indian Himalayan region. VS were incorporated in the experimental plots (Entisols) in a randomized complete block design in permanent 100 × 20 m (2000 m2) plots with a 2% slope to evaluate the effects of vegetation strips on run‐off, soil loss and crop yield. Three treatments were evaluated: (i) without VS with recommended NPK under conventional tillage, (ii) panicum as VS with recommended NPK under conventional tillage and (iii) palmarosa+ that consists of palmarosa as VS along with organic amendments (farmyard manure, vermicompost and poultry manure) and weed mulch under minimum tillage. The results show that soil loss and run‐off were significantly lower (< 0.05) in plots under palmarosa+ than without VS treatment. Mean soil loss of 3.4, 5.2 and 7.1 t/ha was recorded from palmarosa+, panicum and without VS treated plots, respectively. Mean run‐off was 234, 356 and 428 mm from plots under palmarosa+, panicum and without VS, respectively. Maize yield was lower on the plots under palmarosa+ compared with panicum, but significantly higher (< 0.05) than without a strip. The succeeding rainfed wheat yield was significantly greater in plots under palmarosa+ than in the initial years. The wheat yield equivalent was significantly higher in plots under palmarosa+ followed by panicum and without VS. Thus, vegetation strips are recommended for wider adoption to reduce run‐off and soil loss and to increase crop yield. The long‐term goal is to achieve a palmarosa+ system (palmarosa as a vegetation strip along with organic amendments, farmyard manure, vermicompost and poultry manure) and weed mulch under minimum tillage.  相似文献   
102.
The objective of this work was to investigate the efficacy of a prepackaged combined formulation, Companion (carbendazim 12% + mancozeb 63% WP), sole application of carbendazim 50% WP, manozeb 75% WP and methyl jasmonate (MeJA), an inducer of systemic acquired resistance on disease severity and their role in post-infectional defense responses in chilli seedlings against Sclerotium rolfsii. Seeds were treated for 8 h with MeJA (2.5 mM and 5.0 mM) and each of fungicides (500 ppm), and were sown in pots containing soil and fungal inocula (95:5 w/w). At 15 days after sowing maximum defense against fungal infection was exhibited by Companion comparably followed by the sole application of carbendazim and mancozeb. MeJA reduced percent mortality of S. rolfsii-infected chilli seedlings significantly as compared to the inoculated control. Assessment of peroxidase (POX) and esterase (EST) at 15 days after sowing revealed the increased activity under inoculated condition. Highest POX activity in MeJA treatments (5 mM > 2.5 mM) was followed by the Companion treatment. Highest EST activity was registered in Companion treatment. The zymogram of POX isozymes showed over-expression of POX 2 and POX 4 isoforms, and induction of POX 1 isoform in inoculated treatments. On the other hand, that of EST isozymes showed induction of EST 1 isoform in Companion, carbendazim and MeJA treatments. All EST isoforms were over-expressed in Companion-treated seedlings. Both fungicides and MeJA showed significant effects on disease severity, induction of defense enzymes and isozyme pattern in S. rolfsii-infected chilli seedlings. Contact and systemic fungicides under the experiment demonstrated differential responses. The combination formulation was superior in disease control to application of the fungicide components individually. They compared favourably with MeJA in induction of defense-related enzyme activities. All these findings are new with respect to the chilli-S. rolfsii host–pathogen interaction system, S. rolfsii representing the sclerotial basidiomycetes in particular.  相似文献   
103.
The toxicity of four concentrations (1, 5, 10 and 20% w/v) of an aqueous extract from the weed, Clerodendrum viscosum Ventenat (Verbenaceae) was investigated under field conditions of the North Bengal University, Darjeeling, West Bengal, India for managing two major pests of tea, Camellia sinensis (L), namely the tea mosquito bug, Helopeltis theivora Waterhouse, (Heteroptera: Miridae) and the tea red spider mite, Oligonychus coffeae Nietner, (Acarina: Tetranychidae). Four field trials, two for red spider mite and two for tea mosquito bug, were conducted during April–May 2008 and October–November 2009 following a Randomized Block design. The aqueous extract of C. viscosum effectively and significantly reduced the mite population as well as infestation of tea mosquito bug by 68–95% and 73–86%, respectively, and their bioefficacy is comparable to synthetic and neem pesticides. No phytotoxic effect (score 0–5% and grade 1) was observed in the tea bushes sprayed with different doses of aqueous extract of C. viscosum in the field. Made tea samples were taint free. Organoleptic test revealed leaf-infusions and liquor strength as good, scoring 6.5–7.0 on a 10 point scale. Availability and distribution of this weed (C. viscosum) in and around tea-growing areas of sub Himalayan region, along with its processing for the feasibility of including C. visosum extracts in the current IPM programme is discussed.  相似文献   
104.
The photodegradation of fluchloralin by UV irradiation or sunlight in aqueous methanolic solution has been examined. In the presence of titanium dioxide five photoproducts were obtained, but only four in its absence. One photoproduct, 2, 2'-azoxy-bis(alpha,alpha,alpha-trifluoro-6-nitro-p-toluidine) is reported for the first time as a metabolite of fluchloralin. In natural sunlight the rate of degradation was higher than in UV light and titanium dioxide had almost no effect on the rate of degradation.  相似文献   
105.
106.
The mulberry leaves have been considered as a sole food source for silkworm, Bombyx mori (L.). In present work an attempt was made to investigate the role of low molecular weight peptide(s) isolated from mulberry leaves on silkworm rearing. Also we have tried to find out the role of free-radical scavenging activities of isolated peptide(s) on silkworm growth. Larval growth rate was found effective under the influence of peptide(s). Consumption rate of larvae after peptide(s) treatment on mulberry leaves was significantly enhanced over control. High antioxidant activity was found in Low molecular weight peptide(s) which have an effect on silkworm.  相似文献   
107.
A simple and rapid Enzyme Linked ImmunoSorbant Assay (ELISA) is described and validated for testosterone, estradiol, and 17,20-dihydroxy-4-pregnen-3-one (17,20P). A general procedure for preparation of the acetylcholinesterase labeled steroid is described which is applicable to any steroid. Use of acetylcholinesterase tracer increased the sensitivity of assay so that reliable measurements of each steroid could be achieved with only 10 l of plasma. The ELISA was applied to measurement of all three steroids every hour for over 24 hours in a female trout using cannulation of the dorsal aorta. This high sampling frequency revealed several short-term (<2 h) episodic pulses of testosterone and estradiol.  相似文献   
108.
Toxicokinetic behavior, recovery, and metabolism studies of ACTP ester and its effect on cytochrome P(450) content of liver microsomal pellet were carried out in black Bengal goat after a single intravenous administration of 11.88 mg kg(-1) and consecutive oral administration of 79.22 mg kg(-1) for 7 days. ACTP ester achieved a maximum blood concentration of 42.64 +/- 4.26 microg mL(-1) at 0.08 h after intravenous administration followed by a sharp decline until 0.5 h, and the minimum blood concentration was recorded at 36 h (1.93 +/- 0.14 microg mL(-1)) postdosing. The kinetic behavior of ACTP ester followed a "two-compartment open model". Comparatively shorter alpha (0.81 +/- 0.02 h(-1)) and greater t1/2 (alpha) (0.86 +/- 0.03 h) indicated a slower rate of distribution of ACTP ester in goat. The t1/2(beta)()) (14.83 +/- 1.49 h) and V(d(area)) (0.91 +/- 0.19 L kg(-1)) suggested a longer elimination phase with general distribution in all compartments of the body. The higher T/B and K12/K21 values associated with a lower f(c) value suggested longer persistence in the tissue compartment at higher concentration. The higher Cl(R) compared to Cl(H) indicated the major amount was eliminated by the kidney. Maximum concentration of ACTP ester including its metabolites, triclopyr acid and trichloropyridinol, was excreted through urine at 48 h. The recovery of ACTP ester including metabolites after repeated nontoxic oral dose administration was 70.09%, of which recovery from feces was 4.45%, suggesting the major portion of administered ACTP ester was absorbed through the gastrointestinal tract of the goat. All of the tissues contained ACTP ester and its metabolites. ACTP ester did not alter the cytochrome P(450) content of the liver tissue following repeated nontoxic oral dose administration for 7 days.  相似文献   
109.
This study investigated the nutritional effect of sunflower seed proteinfraction (SSPF) extracted with isopropanol on growth, plasma and tissuelipid profile, protein content and erythrocyte membrane lipid profile ofrats. Dehulled sunflower seeds were extracted with isopropanol at 50±1 °C resulting in a protein fraction (71.5%) with low residualchlorogenic acid (0.07%) and fiber (3.3%) contents. Rats fed thesunflower seed protein fraction had a similar body weight gain and foodefficiency ratios in comparison to those fed casein. Rats fed SSPF incontrast had a significantly higher growth and food efficiency ratio thanthe rats fed sunflower meal (SM), extracted with hexane. However,dietary proteins exerted a separate effect on plasma total cholesterol,low density lipoprotein (LDL)-cholesterol, low density lipoprotein to highdensity lipoprotein cholesterol (LDL-C/HDL-C) ratio and triglyceridecontent. Sunflower seed protein fraction resulted in a significantdecrease in plasma cholesterol (p < 0.05) and LDL-cholesterol (p <0.02) levels compared to the casein fed rats. Membrane phospholipidprofile also showed a marked variation with the type of dietary protein.Rats fed SSPF and SM did not show much variation in plasma lipids, plasmaproteins, liver and brain lipids and membrane phospholipid concentrations.Protein content, liver and brain lipid profile of the groups fed SSPF andcasein were comparable, suggesting that the nutritional value of SSPF isbetter than SM and equivalent to that of casein.  相似文献   
110.
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