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161.
The beneficial effects of planting mixtures comprising of fly ash at the rate of 66%, 33% and 17% by soil volume were assessed for the early growth of two economic tree species, teak (Tectona grandis) and leucaena (Leucaena leucocephala) in rainfed Semi-Arid Tropical (SAT) Alfisols in India. Measurements of tree growth were made at six monthly intervals over a 3-year period. Fly ash at 66% by soil volume of the planting pit significantly increased the diameter of teak at breast height (dbh). In leucaena, application of fly ash at 17% by soil volume was found to be effective in increasing dbh during most of the study period. Changes in soil physicochemical properties (bulk density, water retention at 0.033 and 1.5 MPa, profile moisture content, pH, soluble salt content and organic carbon) were simultaneously studied. Among these soil properties, plant available water (PAW) and organic carbon (OC) contents explained variations in diameter at breast height (dbh) in teak during most of the sampling period, while none of the soil properties significantly explained dbh in leucaena. The highest dose of fly ash applied (66% by volume) decreased bulk density (BD) and increased PAW in teak and to an extent in leucaena during the first 2 years of tree growth. Higher profile moisture content was noted in pits treated with 66% fly ash during the dry period of November (after the end of seasonal rainfall which occurred from June to October) during the first and second year after application. An erratum to this article can be found at  相似文献   
162.
163.
Rice production is severely constrained by the moisture stress. The present study was undertaken to transfer two important QTLs viz., (qDTY2.2 and qDTY4.1), which controls yield under moisture stress (DTY) into two elite varieties, that is, MTU1010 and NLR34449 through marker-assisted breeding. Foreground and background selections of backcross generations, that is, BC1F1, BC2F1 and BC2F2 identified several promising introgression lines (ILs) with two QTLs and single QTLs with an appreciable level of recovery of recipient parent genome. In ILs, the recovery of MTU1010 genome content was estimated to be 83%–93% while the recovery of NLR34449 was 84%–92%. The two-QTL ILs of MTU1010 and NLR34449 backgrounds (qDTY2.2 and qDTY4.1) have shown substantial yield advantage (32 to 84%) over the single-QTL ILs (either qDTY2.2 or qDTY4.1) under moisture stress conditions. Among all, two ILs, MBC-124 and NBC-127 are the best high yielding lines under moisture stress conditions. These outyielded ILs have the potential to be released as varieties in rainfed ecosystem and also can be used as donors in the existing breeding programme in rice.  相似文献   
164.
Cowpea mild mottle virus (CPMMV) is an emerging severe disease of soybean. The resistant genotypes, DS 12‐5 and SL958, were crossed with susceptible genotypes F4C7‐32 and JS335, respectively. Resistance reactions of sap‐inoculated F2 plants and individual F2 plant‐derived F3 families indicated that resistance was controlled by a single dominant gene. Molecular mapping with bulked segregant analysis showed that Satt635 and UO8405 are linked to resistance gene which is located on linkage group H.  相似文献   
165.
R. Mandal  A. Islam 《Geoderma》1979,22(4):315-321
Concentrations of inositol mono-, di- and tri-, tetra-, penta- and hexaphosphate ranged from 5.0 to 12.5, 10.0 to 27.6, 20.0 to 45.0, 22.5 to 64.6, and 20.0 to 275.4 ppm, respectively, in samples of soils that were poorly drained and mostly derived from alluvium. Multiple correlation suggested that the amounts of esters of inositol phosphate other than inositol monophosphate were significantly correlated with organic phosphorus, total phosphorus, organic carbon, total nitrogen, inositol phospate, clay, exchangeable iron and aluminium, and pH. Individually, inositol hexa-, penta-, and di- and triphosphates were significantly correlated with organic phosphorus, total phosphorus, organic carbon, total nitrogen, inositol phosphate, and exchangeable iron and aluminium; inositol tetraphosphate with organic carbon, total nitrogen, inositol phosphate, and exchangeable iron and aluminium; inositol monophosphate with none.  相似文献   
166.
White spot disease caused by white spot syndrome virus (WSSV) is the major issue of huge economic destruction globally in the shrimp aquaculture industry. In the present investigation, WSSV prevalence associated with disease resistance was studied among wild black tiger shrimp, Penaeus monodon (Fabricius) from four distant geographic locations along the East coast of India during 2009–2010. Results suggested that the WSSV prevalence in wild P. monodon was the highest (56.2%) in Chennai, Tamil Nadu followed by Digha, West Bengal (10.9%), Visakhapatnam, Andhra Pradesh (0.6%) and Chilika, Orissa (0%). Quantitative data suggested that the mean copy number of WSSV among these four places was 1.4 × 106, 4.6 × 104, 1.6 × 102 and 2.3 × 102 copies μg?1 shrimp genomic DNA respectively. The disease resistant prevalence using the 71 bp microsatellite DNA marker was the highest among Chilika, Orissa (63.6%) and Visakhapatnam, Andhra Pradesh (63.5%). Higher WSSV prevalence in Chennai, Tamil Nadu and Digha, West Bengal corresponded to lower disease resistant prevalence (24% and 40.2%). Conclusively, probably collection of broodstock of P. monodon from places like Chilika and Visakhapatnam would be a much safer approach for the development of specific pathogen‐resistant shrimp aquaculture.  相似文献   
167.
Abstract

Present study was designed to estimate the average monthly production rate of Ae. aegypti in a rainwater filled bus/truck tire (1.041?m) and car tire (0.737?m) as well as in bus/truck tire lodged with pondwater which are lacking. An average of 3957 Ae. aegypti propagated from single rainwater filled bus/truck tire which was significantly higher than the average number of them produced in a rainwater filled car tire and a pondwater lodged bus/truck tire in a rainy month. Higher water holding capacity might be the cause of difference between the bus/truck tire and the car tire. On other hand, difference in multiple physio-chemical aspects between rainwater and pondwater seemed to be the determining factor to make difference in mosquito breeding potential in a bus/truck tire. It is assumed from the present study that an open dumping ground of discarded tires may account for huge production of Ae. aegypti. Discarded tires are recommended to be kept under shade or covered with polythene-sheet or apertures be made underside each tire for draining out the accumulated rainwater.  相似文献   
168.
Permissible erosion rate also known as soil loss tolerance (‘T’ value) is defined as maximum erosion that can take place on a given soil without degrading its long‐term productivity. In India, default ‘T’ value of 11·2 Mg ha−1 y−1 is used for devising land restoration strategies for different types of soils. However, ability of soil to resist degradation varies with soil type, depth and physico‐chemical characteristics. Therefore, the present investigation was undertaken to determine ‘T’ value of different landforms of Delhi State by taking into account the soil saturated hydraulic conductivity (SHC), bulk density (BD), organic carbon, erodibility and soil pH. Soil state was defined by a quantitative model and scaling functions were used to convert soil parameters to a 0–1 scale. The normalised values were multiplied by appropriate weighting factors based on relative importance and sensitivity analysis of each indicator. Categorical rankings of I, II or III were assigned to soil groups based on overall aggregate score. ‘T’ value of different landforms of Delhi State was computed using the guideline of USDA‐Natural Resource Conservation Services. Majority of landforms of Delhi had ‘T’ value of 12·5 Mg ha−1 y−1, except for the soils of hill terrain, dissected hill, pediment and piedmont plain, where ‘T’ value ranged from 5 to 10 Mg ha−1 y−1. These ‘T’ values could be used for conservation planning and will help the planners in devising suitable land restoration strategies. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
169.
1. Nitrogen-corrected apparent metabolisable energy values (AMEN) of three varieties of sorghum (white-low tannin, brown-medium tannin and red-high tannin) were measured in three species of poultry (cockerel, guinea fowl and Japanese quail) by a practical diet replacement (total collection) method. 2. Each variety of sorghum was tested at two concentrations (200 and 400 g/kg of reference diet) in 6 replications with one cockerel or guinea fowl or two quails per replication. The duration of the trial included a 10 d preliminary feeding period (on conventional grower diet) followed by a 12 d adaptation period (on reference and test diets) and a 3 d balance period (with recording of feed intake and excreta output). 3. The calculated AMEN values of different sorghum varieties were: white--12.9, 12.8 and 12.7; brown--12.7, 12.3 and 12.6; and red--11.4, 11.1 and 11.6 MJ/kg for cockerels, guinea fowls and quails, respectively. The mean AMEN value of red sorghum (11.3 MJ/kg) was significantly lower than those of brown (12.5 MJ/kg) or white sorghum (12.8 MJ/kg). A negative correlation was observed between tannin concentration and AMEN. 4. There was no significant difference in the AMEN values of white, brown and red sorghum varieties to the different poultry species. AMEN values of sorghum for the cockerel could, therefore, be used in practical feed formulation for guinea fowl and quail.  相似文献   
170.
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   
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