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91.
Integrated effects of fly ash (FA), farmyard manure (FYM), and chemical fertilizers recommended dose of fertilizer (RDF) on the performance of rice (Oryza sativa L.) and their residual effect on rapeseed (Brassica camprestris L. vartoria) were studied for two years in loamy acidic inceptisol of Assam, India.

The FA was generated from a bituminous and lignite coal-based captive thermal power plant of Hindustan Paper Corporation Ltd (HPCL), Assam. Rice yields were higher when FA, FYM, and RDF were used collectively vis-à-vis sole application of RDF reflected also in rapeseed under residual effect . FA effect on mean rice equivalent yield of the rice–rapeseed system was the highest (24.4%) under integrated application. Nickel (Ni) and cadmium (Cd) contents in rice decreased with increasing FA, while arsenic (As) was just the opposite. Integration of FA, FYM, and RDF was effective in lowering Ni, Cd, and As in rice compared to 100% RDF alone or together with FA. The residual effect on rapeseed was similar for Ni and As while the Cd content increased. Blending of FA, FYM, and RDF also positively altered the residual soil pH, organic carbon (C), and nitrogen, phosphorus, and potassium (NPK). Thus, FA can be an integral component of integrated plant nutrition system (IPNS) in augmenting crop yield and residual benefits in loamy acid inceptisol.  相似文献   

92.
Characterization of char from the pyrolysis of tobacco   总被引:9,自引:0,他引:9  
Pyrolysis of tobacco was studied in oxidative and nonoxidative (inert) environments at atmospheric pressure and temperatures ranging from 150 to 750 degrees C. The objective was to study the effect of pyrolysis conditions on the characteristics of the solid residue, i.e., char. The char was characterized using cross-polarization (13)C nuclear magnetic resonance (CPMAS NMR), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), the Brunauer-Emmett-Teller (BET) surface area, and the elemental composition. The char yield from pyrolysis (i.e., nonoxidative) decreased sharply with an increase in temperature to ca. 22% (dry, ash-free basis) at high temperatures. In oxidative pyrolysis, i.e., in 5% oxygen, the char was completely oxidized above 600 degrees C. The gaseous product from pyrolysis at high temperatures contained a significant concentration of hydrogen. The surface area of the char was low, with a maximum of 8 m(2)/g at 400 degrees C. SEM analysis indicated that pyrolysis of the tobacco led to a gradual accumulation of inorganic crystals on the exposed surfaces, and some constituents also melted, resulting in the formation of vesicles by evolving gas. NMR analysis showed significant changes in pectin and sugar constituents of the tobacco and breaking of glycosidic bonds of cellulose at 300-500 degrees C before the char became predominantly aromatic at high temperatures. FTIR results showed a continuous decrease in the intensity of the OH stretch with temperature and the aromatic character to be at maximum at 550-650 degrees C. The H/C ratio of the char decreased continuously with temperature, while the O/C ratio became constant above 300 degrees C due to the presence of oxides and carbonates in the char. The results are consistent with the analysis of the evolved gases.  相似文献   
93.
BACKGROUND: The insulin-like growth factor (IGF) system is implicated in the pathogenesis of diabetes and cardiovascular disease. OBJECTIVE: We report the effects of total energy intake on the IGF system in two populations with markedly different dietary macronutrient intake and cardiovascular event rate. DESIGN, SUBJECTS AND SETTING: Dietary macronutrient intake was measured in a specific Gujarati migrant community in Sandwell, UK (n=205) compared with people still resident in the same villages of origin in India (n=246). Fasting IGF-I, IGF-binding protein (IGFBP)-1 and IGFBP-3, insulin and glucose (0 and 2-hour) were measured. RESULTS: Total energy and total fat intake were higher in UK migrants, as were IGFBP-3 and IGF-I (mean (95% confidence interval): 145.9 (138.1-153.6) vs. 100.9 (94.6-107.3) ng ml(-1); F=76.6, P<0.001). IGFBP-1 was lower in UK migrants (29.5 (25.9-33.0) vs. 56.5 (50.6-62.5) microg l(-1); F=48.4, P<0.001). At both sites, IGF-I correlated positively with total energy (Spearman's rho=0.45, P<0.001) and total fat (rho=0.44, P<0.001) as did IGFBP-3 with total energy (rho=0.21, P<0.05) and fat (rho=0.26, P<0.001). Conversely, in Indian Gujaratis, IGFBP-1 fell with increasing total energy (rho=-0.27, P<0.001) and fat intake (rho=-0.26, P<0.01) but not in UK Gujaratis. Multiple linear regression modelling showed that increasing quartiles of fat intake were associated with higher IGF-I (beta=0.42, P=0.007) independent of age, body mass index, plasma insulin, fatty acids and 2-hour glucose. CONCLUSION: In these genetically similar groups, migration to the UK and adoption of a different diet is associated with marked changes in the IGF system, suggesting that environmental factors profoundly modulate serum concentrations and actions of IGFs.  相似文献   
94.
Changes in soil properties and yield response in relation to tillage and residue management treatments in an irrigated groundnut (Arachis hypogea L.)—wheat (Triticum aestivum, L.) rotation on a sandy soil (1972–1974) and on a sandy loam soil (1974–1976) were evaluated. Tillage treatments (T1 and T2) did not cause significant changes in soil properties. Incorporation of crop residues (5 t residue per ha per crop, T3) caused a substantial increase in organic C, available N, and NaHCO3 -extractable P contents in the top 15 cm of both soils. Residue management treatments (T3, T4 and T5) showed no significant effect on soil bulk density and exchangeable K. Crop yields under no-tillage (T1) and conventional tillage (control, T2) were comparable on sandy soil but on the sandy loam soil, no-tillage yielded significantly lower than conventional tillage. Compared with the control, incorporation of crop residues (T3) caused higher yields on sandy soil for groundnut and wheat by 34.1 and 47.4%, respectively, and on sandy loam by 17.1 and 7.2%, respectively. Mulching with crop residues conserved soil moisture and reduced maximum soil temperature (1.5–5.3°C in groundnut and 1.5–2.9°C in wheat) but other measured soil properties were not significantly affected. Significant yield increase due to residue mulching (T4) was observed in sandy soil but it was significantly less than when total crop residue was incorporated (T3). Increased wheat root-weight density in the top 15 cm soil with residue mulching was not reflected in grain yield. Compared with the incorporation of the total amount of crop residue (T3), incorporation of half the amount and application of the other half as mulch (T5) caused lower yields — on sandy soil for groundnut and wheat by 31.5 and 15.7%, respectively, and on sandy loam by 4.8 and 3.6%, respectively.  相似文献   
95.
Irrigated green forage production under reduced tillage is thwarted by the failure to obtain adequate N fertilization. Forage accumulation, yield and nitrogen response in relation to tillage and N application were studied for two years during 1980–1982. Forage accumulation, plant height and final forage yield were significantly affected under minimum tillage (T1). However, plant growth and green and dry forage yields were comparable under reduced (T2) and conventional (T3) tillage. Reduction in yield under T1 was associated with restricted root growth and high soil strength and bulk density in the surface and subsurface layers. The optimum dose of N for T1, T2 and T3 was calculated to be 107, 120 and 113 kg N ha?1 and the estimated dry matter yield for these rates of N under each of the three tillage systems was 6.6, 9.1 and 9.5 t ha?1, respectively. The interaction between different tillage systems and N application rates for green and dry matter production was not significant.  相似文献   
96.
Pigeonpea [Cajanus cajan (L.) Millsp.] is an important legume crop in South Asia, East and southern Africa, and the Caribbean. Pod fly (Melanagromyza obtusa Malloch) and pod wasp (Tanaostigmodes cajaninae La Salle) are important constraints to increase the production and productivity of pigeonpea under subsistence farming conditions. Host plant-resistance can be used as an important component for the management of these pests, and therefore, we evaluated 28 accessions of wild relatives of pigeonpea for resistance to these pests. There were significant inter- and intra-species differences in the relative susceptibility to pod fly and pod wasp damage. Accessions belonging to Cajanus scarabaeoides (L.) Thouars, C. sericeus (Benth. ex Bak.) van der Maesen, Rhynchosia bracteata Benth. ex Bak., C. acutifolius (F.v. Muell.) van der Maesen, C. lineatus (W. & A.) van der Maesen, and C. albicans (W. & A.) van der Maesen showed resistance to pod fly damage, while those from C. platycarpus (Benth.) van der Maesen, C. cajanifolius (Haines) van der Maesen and R. aurea DC. were susceptible. For the pod wasp, some of the accessions from C. scarabaeoides, C. albicans, Flemingia stricta Roxb., and R. bracteata (Roxb.) Wight showed a resistant reaction, while ICPW 83 belonging to C. scarabaeoides showed a susceptible reaction. ICPW 141, ICPW 278, and ICPW 280 (C. scarabaeoides), ICPW 214 (R. bracteata), ICPW 14 (C. albicans), and ICPW 202 (F. stricta) showed resistance to both pod fly and pod wasp damage. There was considerable variation in accessions belonging to different species for their susceptibility to pod fly and pod wasp, which can be exploited to breed for resistance to these pests. There was a negative association between pod wasp and pod borer damage, and therefore, it is important to keep track of the relative susceptibility of pigeonpea genotypes to pod wasp, while breeding for resistance to pod borers.  相似文献   
97.
The present study was undertaken in five major forest types (dominated by Quercus semecarpifolia, Quercus floribunda, Acer acuminatum, Abies pindrow and Aesculus indica, respectively) between 2400 and 2850 m a.s.l. in a moist temperate forest of the Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim was to assess the variation in composition and diversity in different vegetation layers, i.e., herb, shrub and tree, among these five forest types. Diversity indices, such as the Shannon-Wiener diversity index, density, total basal cover, Simpson’s concentration of dominance index, Simpson’s diversity index, Pielou’s equitability, species richness, species heterogeneity and β-diversity, were calculated to understand community structures. Dominance-diversity curves were drawn to ascertain resource apportionment among various species in different forest types.  相似文献   
98.
The legume pod borer, Helicoverpa armigera (Hübn.), is one of the major constraints to chickpea production, and host plant resistance is an important component for the management of this pest. The levels of resistance in the cultivated chickpea are low to moderate, and therefore, we evaluated 17 accessions of perennial Cicer along with three cultivated chickpea genotypes for resistance to H. armigera. There was a significant reduction in both leaf feeding and larval weights when the larvae were fed on the leaves of Cicer microphyllum Benth. accessions ICC 17146, ICC 17236, ICC 17240, and ICC 17248. Relative resistance index based on leaf feeding, larval survival, and larval weight indicated that C. microphyllum accessions ICC 17146, ICC 17236, ICC 17234, ICC 17240, ICC 17243, and ICC 17248 were highly resistant to H. armigera. Under natural infestation, accessions belonging to C. microphyllum, C. canariense Santos Guerra et Lewis, and C. macracanthum M. Pop suffered a damage rating of <2.0 compared to 4.0 in C. judaicum Boiss. accession ICC 17148 (annual species) and 8.5–9.0 in the cultivated chickpeas (1 = <10% leaf area damaged, and, 9 = >80% leaf area damaged). There was considerable diversity in the accessions belonging to perennial wild species of chickpea, and these can be exploited to increase the levels and diversify the basis of resistance to H. armigera in the cultivated chickpea.  相似文献   
99.
Abstract

Efficient nutrient and water use are two important considerations to obtain good harvests of wheat. This necessitates the development of an effective nutrient management technique that not only increases yield, but simultaneously can save nutrient and water use. In this context, a field experiment was conducted at Indian Agricultural Research Institute, New Delhi, India to evaluate the residual effect of sesbania and rice bean (in-situ), subabul (ex-situ) green manuring and Zinc (Zn) fertilization, using chelated Zn-ethylenediaminetetraacetic acid (Zn-EDTA) on nutrient use, yields and water productivity of wheat under rice–wheat cropping system. Among residual effects of green manure crops and Zn fertilization, sesbania and foliar spray of 0.5% chelated Zn-EDTA at 20, 40, 60 and 80 days after sowing (DAS) recorded significantly higher nutrient content and uptake and yields than other green manure crops and Zn treatments. Residual effect of sesbania saved about 46.5?×?103 and 30.5?×?103 L irrigation water per tonne of wheat over subabul and rice bean, respectively. Foliar spray of 0.5% chelated Zn-EDTA at 20, 40, 60 and 80 DAS saved about 55.5?×?103, 47?×?103 and 13?×?103 L irrigation water per tonne wheat over residual effect of 5?kg Zn ha?1 through chelated Zn-EDTA as soil application, 2.5?kg Zn ha?1 through chelated Zn-EDTA as soil application + 1 foliar spray of 0.5% chelated Zn-EDTA at flowering and foliar spray of 0.5% chelated Zn-EDTA at active tillering?+?flowering?+?grain filling, respectively. Correlation analysis showed positive correlation between Zn uptake and grain yield.  相似文献   
100.
Many farmers in southeast Asia are growing rice on unpuddled soil. This practice does not permit breaking of the deadlock of increase in productivity in spite of using high yielding varieties and practising all known scientific technologies. Furthermore, farmers do dry seeding which leads to heavy infestation of weeds and reduces response to other inputs. Similarly, in rice–wheat belt due to short turn around time farmers resort to broadcast sowing of wheat after rice and no data on benefits or otherwise of tillage are available. A field study was therefore conducted for 3 years (1993–1994 to 1995–1996) at the Indian Agricultural Research Institute, New Delhi to study the effect of tillage and seeding methods in rice–wheat cropping system. Treatments included four combinations of two puddling treatments (puddling and no puddling) and two methods of rice seeding (direct seeding and transplanting) in rice and two tillage treatments (zero and conventional tillage) in wheat. Results indicated that puddling increased grain yield of rice by 0.7–1 t ha−1 and of succeeding wheat by 0.2–0.4 t ha−1, straw yield of rice by 0.8–1.7 t ha−1 and of succeeding wheat by 0.1–1.0 t ha−1.

Puddling reduced water requirement of rice by 75 mm ha and increased net return of rice–wheat system by US $175 ha−1. Transplanted rice gave significantly higher grain and straw yields and net returns than direct seeded rice both on puddled and unpuddled seedbed. Conventional tillage in wheat also increased productivity of rice–wheat cropping system significantly over zero tillage after both puddled and non-puddled rice. Our results thus show that rice should be grown on puddled soil and wheat after rice should be sown after conventional tillage.  相似文献   

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